Exactly Solvable Hydrogen-like Potentials and Factorization Method

A set of factorization energies is introduced, giving rise to a generalization of the Schr\"{o}dinger (or Infeld and Hull) factorization for the radial hydrogen-like Hamiltonian. An algebraic intertwining technique involving such factorization energies leads to derive $n$-parametric families of potentials in general almost-isospectral to the hydrogen-like radial Hamiltonians. The construction of SUSY partner Hamiltonians with ground state energies greater than the corresponding ground state energy of the initial Hamiltonian is also explicitly performed.Comment: LaTex file, 21 pages, 2 PostScript figures and some references added. To be published in J. Phys. A: Math. Gen. (1998

Weyl type theorems for restrictions of bounded linear operators

In this paper we give sufficient conditions for which Weyl’s theorems for a bounded linear operator T, acting on a Banach space X, can be reduced to the study of Weyl’s theorems for some restriction of T.peerReviewe

Weyl type theorems for restrictions of bounded linear operators

In this paper we give sufficient conditions for which Weyl’s theorems for a bounded linear operator T, acting on a Banach space X, can be reduced to the study of Weyl’s theorems for some restriction of T.peerReviewe

Observation of two-wave structure in strongly nonlinear dissipative granular chains

In a strongly nonlinear viscous granular chain under conditions of loading that exclude stationary waves (e.g., impact by a single grain) we observe a pulse that consists of two interconnected but distinct parts. One is a leading narrow "primary pulse" with properties similar to a solitary wave in a "sonic vacuum." It arises from strong nonlinearity and discreteness in the absence of dissipation, but now decays due to viscosity. The other is a broad, much more persistent shock-like "secondary pulse" trailing the primary pulse and caused by viscous dissipation. The medium behind the primary pulse is transformed from a "sonic vacuum" to a medium with finite sound speed. When the rapidly decaying primary pulse dies, the secondary pulse continues to propagate in the "sonic vacuum," with an oscillatory front if the viscosity is relatively small, until its eventual (but very slow) disintegration. Beyond a critical viscosity there is no separation of the two pulses, and the dissipation and nonlinearity dominate the shock-like attenuating pulse which now exhibits a nonoscillatory front

Impacts of chronic wasting disease on a low density mule deer (Odocoileus hemionus) population in the San Andres Mountains, Chihuahuan Desert, New Mexico

Chronic wasting disease (CWD), a contagious neurodegenerative disease of cervids, is becoming increasingly prevalent in the arid Southwest including the Chihuahuan Desert ecoregion. Population effects of CWD are uncertain, particularly in arid environments, as previous work has been on relatively high density deer populations in semi-arid or temperate environments. In 2002, CWD was detected in a low density mule deer (Odocoileus hemionus) population in the arid San Andres Mountains, a Chihuahuan Desert range in southern New Mexico. We determined prevalence and distribution of CWD, and mortality and movements of deer, to assess the potential impact on low density deer populations in arid environments. Repeated seasonal primarily ante-mortem sampling found stable prevalence of 0.000–0.091, 2003–2008. Annual CWD mortality rate was <0.02, including deer that were culled. Monitoring of adult radio-collared deer showed no dispersal movements away from home ranges, with maximum movements of ≤20 km; similarly, no juveniles dispersed from maternal ranges. Distribution of infected deer was strongly related to presence of other infected deer. Annual survival rates of mule deer and population rate-of-increase suggested little effect of CWD on population-level mortality given observed prevalence. Transmission and reservoirs of CWD in the SAM were likely limited by low deer densities, patchy distribution, and environmental characteristics (i.e., low clay content of soils) unfavorable to prion persistence, characteristics that are typical of most mule deer populations in the Chihuahuan Desert ecoregion.La enfermedad crónica degenerativa (por sus siglas en inglés: CWD), una enfermedad neurodegenerativa contagiosa de los cérvidos, se está haciendo cada vez más frecuente en el suroeste árido americano incluyendo la ecoregión del desierto de Chihuahua. Los efectos de la CWD sobre poblaciones de cérvidos silvestres son inciertos, particularmente en ambientes áridos, ya que el trabajo previo ha estado en poblaciones de ciervos de densidad relativamente alta en ambientes semi-áridos o templados. En 2002, la CWD fue detectada en una población de venado bura (Odocoileus hemionus) de baja densidad en las áridas montañas de San Andrés, una región del Desierto Chihuahuense en el sur de Nuevo México. Se determinó la prevalencia y distribución de CWD, y la mortalidad y los movimientos de los venados, para evaluar su impacto potencial en poblaciones de baja densidad en ambientes áridos. En el muestreo ante-mortem previo repetido estacionalmente se encontró prevalencia estable de 0,000–0,091, 2003–2008. La tasa anual de mortalidad por CWD fue <0,02, incluyendo venados que fueron sacrificados. El monitoreo de venados con radio-collares adultos no mostró movimientos de dispersión fuera de los rangos de origen, con movimientos máximos de ≤20 km; de manera similar, no hay juveniles dispersos de los rangos maternos. La distribución de los venados infectados estaba fuertemente relacionada con la presencia de otros venados infectados. Las tasas anuales de supervivencia del venado mula y la tasa de aumento de la población sugirieron un efecto pequeño de la CWD en la mortalidad a nivel de la población dada la prevalencia observada. La transmisión y los depósitos de CWD en el SAM (Montañas San Andrés) fueron probablemente limitados por la baja densidad de los venados, su distribución irregular y las características ambientales (es decir, bajo contenido de arcilla de los suelos) desfavorables a la persistencia de priones, características típicas de la mayoría de las poblaciones de venados bura en la ecorregión del Desierto Chihuahuense

Distorted Heisenberg Algebra and Coherent States for Isospectral Oscillator Hamiltonians

The dynamical algebra associated to a family of isospectral oscillator Hamiltonians is studied through the analysis of its representation in the basis of energy eigenstates. It is shown that this representation becomes similar to that of the standard Heisenberg algebra, and it is dependent of a parameter $w\geq 0$. We name it {\it distorted Heisenberg algebra}, where $w$ is the distortion parameter. The corresponding coherent states for an arbitrary $w$ are derived, and some particular examples are discussed in full detail. A prescription to produce the squeezing, by adequately selecting the initial state of the system, is given.Comment: 21 pages, Latex, 3 figures available as hard copies upon request from the first Autho

Octopus maya white body show sex-specific transcriptomic profiles during the reproductive phase, with high differentiation in signaling pathways

White bodies (WB), multilobulated soft tissue that wraps the optic tracts and optic lobes, have been considered the hematopoietic organ of the cephalopods. Its glandular appearance and its lobular morphology suggest that different parts of the WB may perform different functions, but a detailed functional analysis of the octopus WB is lacking. The aim of this study is to describe the transcriptomic profile of WB to better understand its functions, with emphasis on the difference between sexes during reproductive events. Then, validation via qPCR was performed using different tissues to find out tissue-specific transcripts. High differentiation in signaling pathways was observed in the comparison of female and male transcriptomic profiles. For instance, the expression of genes involved in the androgen receptor-signaling pathway were detected only in males, whereas estrogen receptor showed higher expression in females. Highly expressed genes in males enriched oxidation-reduction and apoptotic processes, which are related to the immune response. On the other hand, expression of genes involved in replicative senescence and the response to cortisol were only detected in females. Moreover, the transcripts with higher expression in females enriched a wide variety of signaling pathways mediated by molecules like neuropeptides, integrins, MAPKs and receptors like TNF and Toll-like. In addition, these putative neuropeptide transcripts, showed higher expression in females' WB and were not detected in other analyzed tissues. These results suggest that the differentiation in signaling pathways in white bodies of O. maya influences the physiological dimorphism between females and males during the reproductive phase

Mapping Satellite Inherent Optical Properties Index in Coastal Waters of the Yucatán Peninsula (Mexico)

[EN] The Yucatan Peninsula hosts worldwide-known tourism destinations that concentrate most of the Mexico tourism activity. In this region, tourism has exponentially increased over the last years, including wildlife oriented tourism. Rapid tourism development, involving the consequent construction of hotels and tourist commodities, is associated with domestic sewage discharges from septic tanks. In this karstic environment, submarine groundwater discharges are very important and highly vulnerable to anthropogenic pollution. Nutrient loadings are linked to harmful algal blooms, which are an issue of concern to local and federal authorities due to their recurrence and socioeconomic and human health costs. In this study, we used satellite products from MODIS (Moderate Resolution Imaging Spectroradiometer) to calculate and map the satellite Inherent Optical Properties (IOP) Index. We worked with different scenarios considering both holiday and hydrological seasons. Our results showed that the satellite IOP Index allows one to build baseline information in a sustainable mid-term or long-term basis which is key for ecosystem-based management.This research was funded by CONACYT with a doctorate scholarship to Jesús A. Aguilar-Maldonado,with the announcement number 251025 in 2015. María-Teresa Sebastiá-Frasquet was a beneficiary of the BEST/2017/217 post-doctoral research grant, supported by the Valencian Conselleria d’Educació, Investigació,Cultura i Esport (Spain) during her stay at the Universidad Autónoma de Baja California (Mexico). The Secretariat of Public Education of Mexico (SEP) under the Program for Professional Development Teacher, covered the costs of publication in open access.Aguilar-Maldonado, J.; Santamaría-Del-Ángel, E.; González-Silvera, A.; Cervantes-Rosas, OD.; Sebastiá-Frasquet, M. (2018). Mapping Satellite Inherent Optical Properties Index in Coastal Waters of the Yucatán Peninsula (Mexico). Sustainability. 10(6). https://doi.org/10.3390/su10061894S1894106Bentz, J., Lopes, F., Calado, H., & Dearden, P. (2016). Sustaining marine wildlife tourism through linking Limits of Acceptable Change and zoning in the Wildlife Tourism Model. Marine Policy, 68, 100-107. doi:10.1016/j.marpol.2016.02.016Jarvis, D., Stoeckl, N., & Liu, H.-B. (2016). The impact of economic, social and environmental factors on trip satisfaction and the likelihood of visitors returning. Tourism Management, 52, 1-18. doi:10.1016/j.tourman.2015.06.003Ziegler, J., Dearden, P., & Rollins, R. (2012). But are tourists satisfied? Importance-performance analysis of the whale shark tourism industry on Isla Holbox, Mexico. Tourism Management, 33(3), 692-701. doi:10.1016/j.tourman.2011.08.004Duffus, D. A., & Dearden, P. (1990). Non-consumptive wildlife-oriented recreation: A conceptual framework. Biological Conservation, 53(3), 213-231. doi:10.1016/0006-3207(90)90087-6Aguilar-Trujillo, A. C., Okolodkov, Y. B., Herrera-Silveira, J. A., Merino-Virgilio, F. del C., & Galicia-García, C. (2017). Taxocoenosis of epibenthic dinoflagellates in the coastal waters of the northern Yucatan Peninsula before and after the harmful algal bloom event in 2011–2012. Marine Pollution Bulletin, 119(1), 396-406. doi:10.1016/j.marpolbul.2017.02.074Ulloa, M. J., Álvarez-Torres, P., Horak-Romo, K. P., & Ortega-Izaguirre, R. (2017). Harmful algal blooms and eutrophication along the mexican coast of the Gulf of Mexico large marine ecosystem. Environmental Development, 22, 120-128. doi:10.1016/j.envdev.2016.10.007Henrichs, D. W., Hetland, R. D., & Campbell, L. (2015). Identifying bloom origins of the toxic dinoflagellate Karenia brevis in the western Gulf of Mexico using a spatially explicit individual-based model. Ecological Modelling, 313, 251-258. doi:10.1016/j.ecolmodel.2015.06.038Murray, G. (2007). Constructing Paradise: The Impacts of Big Tourism in the Mexican Coastal Zone. Coastal Management, 35(2-3), 339-355. doi:10.1080/08920750601169600Heisler, J., Glibert, P. M., Burkholder, J. M., Anderson, D. M., Cochlan, W., Dennison, W. C., … Suddleson, M. (2008). Eutrophication and harmful algal blooms: A scientific consensus. Harmful Algae, 8(1), 3-13. doi:10.1016/j.hal.2008.08.006Smayda, T. J. (2008). Complexity in the eutrophication–harmful algal bloom relationship, with comment on the importance of grazing. Harmful Algae, 8(1), 140-151. doi:10.1016/j.hal.2008.08.018Klemas, V. (2012). Remote Sensing of Algal Blooms: An Overview with Case Studies. Journal of Coastal Research, 278, 34-43. doi:10.2112/jcoastres-d-11-00051.1COFEPRIS (Comisión Federal para la Protección contra Riesgos Sanitarios/Federal Commission for Protection against Health Risks)https://www.gob.mx/cofepris/acciones-y-programas/antecedentes-en-mexico-76707Antoine, D., & Morel, A. (1996). Oceanic primary production: 1. Adaptation of a spectral light-photosynthesis model in view of application to satellite chlorophyll observations. Global Biogeochemical Cycles, 10(1), 43-55. doi:10.1029/95gb02831Barocio-León, Ó. A., Millán-Núñez, R., Santamaría-del-Ángel, E., González-Silvera, A., & Trees, C. C. (2006). Spatial variability of phytoplankton absorption coefficients and pigments off Baja California during November 2002. Journal of Oceanography, 62(6), 873-885. doi:10.1007/s10872-006-0105-zSmith, V. H., Tilman, G. D., & Nekola, J. C. (1999). Eutrophication: impacts of excess nutrient inputs on freshwater, marine, and terrestrial ecosystems. Environmental Pollution, 100(1-3), 179-196. doi:10.1016/s0269-7491(99)00091-3Limoges, A., Londeix, L., & de Vernal, A. (2013). Organic-walled dinoflagellate cyst distribution in the Gulf of Mexico. Marine Micropaleontology, 102, 51-68. doi:10.1016/j.marmicro.2013.06.002Jiang, L., Xia, M., Ludsin, S. A., Rutherford, E. S., Mason, D. M., Marin Jarrin, J., & Pangle, K. L. (2015). Biophysical modeling assessment of the drivers for plankton dynamics in dreissenid-colonized western Lake Erie. Ecological Modelling, 308, 18-33. doi:10.1016/j.ecolmodel.2015.04.004Aguilar-Maldonado, J., Santamaría-del-Ángel, E., González-Silvera, A., Cervantes-Rosas, O., López, L., Gutiérrez-Magness, A., … Sebastiá-Frasquet, M.-T. (2018). Identification of Phytoplankton Blooms under the Index of Inherent Optical Properties (IOP Index) in Optically Complex Waters. Water, 10(2), 129. doi:10.3390/w10020129Wei, G., Tang, D., & Wang, S. (2008). Distribution of chlorophyll and harmful algal blooms (HABs): A review on space based studies in the coastal environments of Chinese marginal seas. Advances in Space Research, 41(1), 12-19. doi:10.1016/j.asr.2007.01.037Urquhart, E. A., Schaeffer, B. A., Stumpf, R. P., Loftin, K. A., & Werdell, P. J. (2017). A method for examining temporal changes in cyanobacterial harmful algal bloom spatial extent using satellite remote sensing. Harmful Algae, 67, 144-152. doi:10.1016/j.hal.2017.06.001Harvey, E. T., Kratzer, S., & Philipson, P. (2015). Satellite-based water quality monitoring for improved spatial and temporal retrieval of chlorophyll-a in coastal waters. Remote Sensing of Environment, 158, 417-430. doi:10.1016/j.rse.2014.11.017Malthus, T. J., & Mumby, P. J. (2003). Remote sensing of the coastal zone: An overview and priorities for future research. International Journal of Remote Sensing, 24(13), 2805-2815. doi:10.1080/0143116031000066954Matthews, M. W. (2011). A current review of empirical procedures of remote sensing in inland and near-coastal transitional waters. International Journal of Remote Sensing, 32(21), 6855-6899. doi:10.1080/01431161.2010.512947Miller, R. L., & McKee, B. A. (2004). Using MODIS Terra 250 m imagery to map concentrations of total suspended matter in coastal waters. Remote Sensing of Environment, 93(1-2), 259-266. doi:10.1016/j.rse.2004.07.012Loisel, H., Vantrepotte, V., Norkvist, K., Mériaux, X., Kheireddine, M., Ras, J., … Moutin, T. (2011). Characterization of the bio-optical anomaly and diurnal variability of particulate matter, as seen from scattering and backscattering coefficients, in ultra-oligotrophic eddies of the Mediterranean Sea. Biogeosciences, 8(11), 3295-3317. doi:10.5194/bg-8-3295-2011Werdell, P. J., Franz, B. A., Bailey, S. W., Feldman, G. C., Boss, E., Brando, V. E., … Mangin, A. (2013). Generalized ocean color inversion model for retrieving marine inherent optical properties. Applied Optics, 52(10), 2019. doi:10.1364/ao.52.002019Brezonik, P. L., Olmanson, L. G., Finlay, J. C., & Bauer, M. E. (2015). Factors affecting the measurement of CDOM by remote sensing of optically complex inland waters. Remote Sensing of Environment, 157, 199-215. doi:10.1016/j.rse.2014.04.033Odermatt, D., Gitelson, A., Brando, V. E., & Schaepman, M. (2012). Review of constituent retrieval in optically deep and complex waters from satellite imagery. Remote Sensing of Environment, 118, 116-126. doi:10.1016/j.rse.2011.11.013Enriquez, C., Mariño-Tapia, I., Jeronimo, G., & Capurro-Filograsso, L. (2013). Thermohaline processes in a tropical coastal zone. Continental Shelf Research, 69, 101-109. doi:10.1016/j.csr.2013.08.018Estadísticas del Agua en México. Secretaría de Medio Ambiente y Recursos Naturaleshttp://201.116.60.25/publicaciones/EAM_2016.pdfArcega-Cabrera, F., Garza-Pérez, R., Noreña-Barroso, E., & Oceguera-Vargas, I. (2014). Impacts of Geochemical and Environmental Factors on Seasonal Variation of Heavy Metals in a Coastal Lagoon Yucatan, Mexico. Bulletin of Environmental Contamination and Toxicology, 94(1), 58-65. doi:10.1007/s00128-014-1416-1Lopez-Maldonado, Y., Batllori-Sampedro, E., Binder, C. R., & Fath, B. D. (2017). Local groundwater balance model: stakeholders’ efforts to address groundwater monitoring and literacy. 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W., Smith, R. C., Baker, K. S., & Clark, D. K. (1988). A semianalytic radiance model of ocean color. Journal of Geophysical Research, 93(D9), 10909. doi:10.1029/jd093id09p10909Roesler, C. S., Perry, M. J., & Carder, K. L. (1989). Modeling in situ phytoplankton absorption from total absorption spectra in productive inland marine waters. Limnology and Oceanography, 34(8), 1510-1523. doi:10.4319/lo.1989.34.8.1510SMN (Servicio Meteorológico Nacional/National Metereological Service)http://smn.cna.gob.mx/es/climatologia/temperaturas-y-lluvias/resumenes-mensuales-de-temperaturas-y-lluviasCarstensen, J., Klais, R., & Cloern, J. E. (2015). Phytoplankton blooms in estuarine and coastal waters: Seasonal patterns and key species. Estuarine, Coastal and Shelf Science, 162, 98-109. doi:10.1016/j.ecss.2015.05.005Winder, M., & Cloern, J. E. (2010). The annual cycles of phytoplankton biomass. 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J., & Herrera-Silveira, J. A. (2010). Dispersion in the Yucatan coastal zone: Implications for red tide events. Continental Shelf Research, 30(2), 127-137. doi:10.1016/j.csr.2009.10.00

Non-Hermitian SUSY Hydrogen-like Hamiltonians with real spectra

It is shown that the radial part of the Hydrogen Hamiltonian factorizes as the product of two not mutually adjoint first order differential operators plus a complex constant epsilon. The 1-susy approach is used to construct non-hermitian Hamiltonians with hydrogen spectra. Other non-hermitian Hamiltonians are shown to admit an extra `complex energy' at epsilon. New self-adjoint hydrogen-like Hamiltonians are also derived by using a 2-susy transformation with complex conjugate pairs epsilon, (c.c) epsilon.Comment: LaTeX2e file, 13 pages, 6 EPS figures. New references added. The present is a reorganized and simplified versio

Echocardiographic assessment of patients with infectious endocarditis: Prediction of risk for complications

AbstractTo enhance the echocardiographic identification of high risk lesions in patients with infectious endocarditis, the medical records and two-dimensional echocardiograms of 204 patients with this condition were analyzed. The occurrence of specific clinical complications was recorded and vegetations were assessed with respect to predetermined morphologic characteristics.The overall complication rates were roughly equivalent for patients with mitral (53%), aortic (62%), tricuspid (77%) and prosthetic valve (61%) vegetations, as well as for those with nonspecific valvular changes but no discrete vegetations (57%), although the distribution of specific complications varied considerably among these groups. There were significantly fewer complications in patients without discernible valvular abnormalities (27%).In native left-sided valve endocarditis, vegetation size, extent, mobility and consistency were all found to be significant univariate predictors of complications. In multivariate analysis, vegetation size, extent and mobility emerged as optimal predictors and an echocardiographic score based on these factors predicted the occurrence of complications with 70% sensitivity and 92% specificity in mitral valve endocarditis and with 76% sensitivity and 62% specificity in aortic valve endocarditis