Putative morphometric evidence of the presence of Acipenser naccarii Bonaparte, 1836 in Iberian rivers, or why ontogenetic allometry needs adequate treatment

He ampliado mi análisis inicial (Rincón, 2000) de los datos publicados sobre la morfometría de esturiones procedentes de aguas de la península Ibérica y de una piscifactoría, presentados como prueba del carácter nativo tanto de Acipenser naccarii Bonaparte, 1836 como de Acipenser sturio L., 1758 en la cuenca del Guadalquivir (Garrido-Ramos et al., 1997), aplicando las mismas técnicas uni- y multivariantes de ajuste de alometrías a una base de datos ampliada con un mayor número de ejemplares de A. naccarii. Como ya ocurrió, la representación gráfica de las diversas medidas cefálicas frente a la longitud total (todas transformadas a logaritmos) y de los componentes principales extraídos por ACP, realizados usando tanto la matriz de covarianza como la de correlación, no ofrecieron indicación alguna de la existencia de dos grupos morfológicamente distintos dentro de los esturiones capturados en aguas de la Península. Además, el relativamente débil (en cuanto a proporción de la varianza total que asumía) gradiente en la anchura del morro que separaba al único ejemplar de piscifactoría de los esturiones salvajes que hallé (Rincón, 2000), fue identificado de nuevo, ahora evidente y nítido, por todas las técnicas anteriores. Finalmente, un AFD mostró que tal diferencia permitía una casi perfecta, altamente significativa, distinción entre los especímenes de piscifactoría y los salvajes, mientras que no hubo gradiente morfométrico estadísticamente significativo que separase los supuestos dos grupos de esturiones salvajes ibéricos. El examen en la base de datos ampliada de las dos variables compuestas que Garrido-Ramos et al. (1997) usaron para distinguir tales dos grupos, confirmó que ambas se hallan gravemente influidas por la alometría ontogenética, llevando, por tanto, a la asignación de los ejemplares grandes o pequeños a grupos distintos. Concluyo, pues, que no hay evidencia morfológica alguna que apoye el supuesto carácter de especie autóctona de A. naccarii en la península Ibérica.I have extended my initial analyses (Rincón, 2000) of a published morphometric data set of sturgeons caught in Iberian rivers and from a fish farm, claimed to prove the native status of both Acipenser naccarii Bonaparte, 1836 and Acipenser sturio L., 1758 in the Guadalquivir basin (Garrido- Ramos et al., 1997), by applying the same uni- and multivariate techniques for allometric adjustment to a database expanded with further A. naccarii specimens. As previously, neither log-log scatterplots of head measurement vs. total length, nor graphical representation of the scores of individual specimens on the principal components (PC) extracted by PCAs performed on the covariance and correlation matrix, respectively, offered any suggestion of the existence of two morphologically dissimilar groups within wild Iberian sturgeons. In addition, the relatively weak (in terms of total variance accounted for) gradient in snout width that separated the one farmed Adriatic sturgeon from the wild fish found in my previous work (Rincón, 2000) was again detected, now clear and distinct, by all those techniques. Furthermore, a DFA showed that such dissimilarity produced almost perfect, highly statistically significant discrimination between farmed and wild fish, while there was no significant gradient separating the two supposed groups of wild Iberian sturgeons. Examination of the two composite variables that Garrido-Ramos et al. (1997) used to separate those groups in the extended database confirmed that they were negatively affected by ontogenetic allometry, therefore leading to the ascription of large and small specimens to different groups. I conclude that there is no morphological evidence to support the claimed autocthonous status of A. naccarii in the Iberian Peninsula.Instituto Español de Oceanografí

Spin-charge separation in strongly interacting finite ladder rings

We study the conductance through Aharonov-Bohm finite ladder rings with strongly interacting electrons, modelled by the prototypical t-J model. For a wide range of parameters we observe characteristic dips in the conductance as a function of magnetic flux, predicted so far only in chains which are a signature of spin and charge separation. These results open the possibility of observing this peculiar many-body phenomenon in anisotropic ladder systems and in real nanoscopic devices.Comment: 4 pages, 6 figure

Transcriptional Response to Acute Thermal Exposure in Juvenile Chinook Salmon Determined by RNAseq.

Thermal exposure is a serious and growing challenge facing fish species worldwide. Chinook salmon (Oncorhynchus tshawytscha) living in the southern portion of their native range are particularly likely to encounter warmer water due to a confluence of factors. River alterations have increased the likelihood that juveniles will be exposed to warm water temperatures during their freshwater life stage, which can negatively impact survival, growth, and development and pose a threat to dwindling salmon populations. To better understand how acute thermal exposure affects the biology of salmon, we performed a transcriptional analysis of gill tissue from Chinook salmon juveniles reared at 12° and exposed acutely to water temperatures ranging from ideal to potentially lethal (12° to 25°). Reverse-transcribed RNA libraries were sequenced on the Illumina HiSeq2000 platform and a de novo reference transcriptome was created. Differentially expressed transcripts were annotated using Blast2GO and relevant gene clusters were identified. In addition to a high degree of downregulation of a wide range of genes, we found upregulation of genes involved in protein folding/rescue, protein degradation, cell death, oxidative stress, metabolism, inflammation/immunity, transcription/translation, ion transport, cell cycle/growth, cell signaling, cellular trafficking, and structure/cytoskeleton. These results demonstrate the complex multi-modal cellular response to thermal stress in juvenile salmon

Convergence to equilibrium for the discrete coagulation-fragmentation equations with detailed balance

Under the condition of detailed balance and some additional restrictions on the size of the coefficients, we identify the equilibrium distribution to which solutions of the discrete coagulation-fragmentation system of equations converge for large times, thus showing that there is a critical mass which marks a change in the behavior of the solutions. This was previously known only for particular cases as the generalized Becker-D\"oring equations. Our proof is based on an inequality between the entropy and the entropy production which also gives some information on the rate of convergence to equilibrium for solutions under the critical mass.Comment: 28 page

Anaerobic digestion of whole-crop winter wheat silage for renewable energy production

With biogas production expanding across Europe in response to renewable energy incentives, a wider variety of crops need to be considered as feedstock. Maize, the most commonly used crop at present, is not ideal in cooler, wetter regions, where higher energy yields per hectare might be achieved with other cereals. Winter wheat is a possible candidate because, under these conditions, it has a good biomass yield, can be ensiled, and can be used as a whole crop material. The results showed that, when harvested at the medium milk stage, the specific methane yield was 0.32 m3 CH4 kg–1 volatile solids added, equal to 73% of the measured calorific value. Using crop yield values for the north of England, a net energy yield of 146–155 GJ ha–1 year–1 could be achieved after taking into account both direct and indirect energy consumption in cultivation, processing through anaerobic digestion, and spreading digestate back to the land. The process showed some limitations, however: the relatively low density of the substrate made it difficult to mix the digester, and there was a buildup of soluble chemical oxygen demand, which represented a loss in methane potential and may also have led to biofoaming. The high nitrogen content of the wheat initially caused problems, but these could be overcome by acclimatization. A combination of these factors is likely to limit the loading that can be applied to the digester when using winter wheat as a substrat

Metodología para la medición de la huella hídrica en la producción de tilapia, cachama y trucha: estudios de caso para el Valle del Cauca (Colombia)

(Eng) The pisciculture sector in Colombia, has grown 13% annually between 1988 and 2013, and it is the sixth major water user. Considering the influence that pisciculture has over the water resources, the water footprint of pisciculture was studied as a sustainability indicator, a method was developed to estimate the water footprint of the sector, which include not only the direct and indirect components, but also the green, blue and grey water footprint. The method was applied to the three most produced species in the country: tilapia (Oreochromis mossambicus), cachama (Piaractus brachypomus) and trout (Oncorhynchus mykiss), to corresponding case studies in Valle del Cauca, Colombia. It was found that the water footprint of tilapia culture is 5,486 m3/Ton, cachama culture is 6,193 m3/Ton, and trout culture is 19,854 m3/Ton. The highest total water footprint for tilapia was that of the concentrated feed, followed by the blue water footprint, associated with the amount of water that remains stored in the ponds, whereas for the cachama and trout, the highest water footprint was grey, due to the high concentrations of solids and nutrients present in fish excretions and unconsumed feed.(Spa) El sector piscícola en Colombia creció en promedio 13% anual de 1988 a 2013 y es el sexto mayor usuario de agua en el país. Considerando la presión que ejerce la producción piscícola sobre las fuentes de agua, se estudió la huella hídrica (HH) de la piscicultura como un indicador de sostenibilidad. Para ello se desarrolló una metodología que mide la HH en el sector, que incluye sus componentes directos e indirectos, así como las huellas hídricas verde, azul y gris. La metodología se aplicó a las tres especies piscícolas más producidas en el país: tilapia (Oreochromis mossambicus), cachama (Piaractus brachypomus) y trucha (Oncorhynchus mykiss), para sendos casos de estudio en el Valle del Cauca, Colombia. Se encontró que la HH total del cultivo de tilapia es de 5,486 m3/Ton, la del cultivo de cachama de 6,193 m3/Ton y la del cultivo de trucha de 19,854 m3/Ton. La huella hídrica total más alta para la tilapia fue la del alimento concentrado, seguida por la huella hídrica azul, asociada a la cantidad de agua que permanece almacenada en los estanques; en la cachama y trucha la mayor huella hídrica total fue la gris, relacionada con las altas concentraciones de sólidos y nutrientes, presentes en las excretas de los peces y en el alimento concentrado no consumido

Co2 methanation in a ni-fe based catalyst fixed bed reactor enhanced by selective water adsorption with lta zeolites (sorption enhanced sabatier reaction – sesar)

A Fixed-Bed reactor improved by selective water adsorption LTA zeolites is proposed as an alternative to the conventional methanation reactors. This reactor produces methane from renewable H2 (i.e. surplus electricity) and high CO2 concentration sources, as could be municipal wastes derived biogas (30%v CO2 + 70%v CH4). As catalyst, a supported (-Al2O3) Ni-Fe (7.5:2.5 wt/wt) was chosen

Efficiency analysis of spur gears with a shifting profile

A model for the assessment of the energy efficiency of spur gears is presented in this study, which considers a shifting profile under different operating conditions (40–600 Nm and 1500–6000 rpm). Three factors affect the power losses resulting from friction forces in a lubricated spur gear pair, namely, the friction coefficient, sliding velocity and load sharing ratio. Friction forces were implemented using a Coulomb’s model with a constant friction coefficient which is the well-known Niemann formulation. Three different scenarios were developed to assess the effect of the shifting profile on the efficiency under different operating conditions. The first kept the exterior radii constant, the second maintained the theoretical contact ratio whilst in the third the exterior radii is defined by the shifting coefficient. The numerical results were compared with a traditional approach to assess the results.The authors would like to acknowledge Project DPI2013-44860 funded by the Spanish Ministry of Science and Technology and the COST ACTION TU 1105 for supporting this research

Investigation of consistency of juvenile surveys (e.g. JUVESAR, JUVENA, ECOCADIZ RECLUTAS) for potential future incorporation in the assessments

Evaluación de recursos marinos vivos en el área del ICESEVALICE

Genetic study of umbilical hernia in thoroughbred race horses

Umbilical hernia is a congenital and inherited disease. Swine is the most affected species followed by young equines. Our aim was to analyze hereditary umbilical hernia in a family of pureblood race horse belonging to one Haras. First, we estimated the prevalence in 155 foals from four families to determine the one with the highest prevalence (20.5%). We performed umbilical hernia digital palpation exam in such a family at 18 months of age for three generations and we developed the genealogy with the purpose of studying the inheritance mechanisms by sex and umbilical hernia size. Umbilical Hernia findings by the sex of the offspring were not significant (c2 1 = 0.26; P=0.61), however mares showed a higher relative risk (1.27) than male horses and her size was smaller (8.69%) than in males (21.75%) (c2 1 =1.77; P=0.18). According to our results we can conclude that umbilical hernia is an oligogenic disease.Fil: Kelly, L. Universidad de la República Oriental del Uruguay. Facultad de Veterinaria. Area Genética; UruguayFil: Medero, A. Universidad de la República Oriental del Uruguay. Facultad de Veterinaria. Departamento de Equinos; UruguayFil: Nicolini, P. Universidad de la República Oriental del Uruguay. Facultad de Veterinaria. Area Genética; UruguayFil: Nimo, A. Universidad de la República Oriental del Uruguay. Facultad de Veterinaria. Area Genética; UruguayFil: Rincón, G. University of California Davis. Department of Animal Science; Unites States of AmericaLa hernia umbilical (HU) es una patología congénita hereditaria que afecta principalmente a suinos y a equinos jóvenes. El objetivo del presente trabajo fue analizar la herencia de HU en 155 potrillos pertenecientes a cuatro familias paternas de equinos Sangre Pura de Carrera de un Haras. Para ello se calculó la prevalencia de HU con el fin de determinar la familia que tuvo mayor prevalencia (20.5%). En dicha familia se estudiaron, durante tres generaciones, el tamaño de la hernia umbilical mediante palpación digital a los 18 meses de edad y se elaboró una genealogía con el fin de estudiar los mecanismos de herencia considerando el sexo y el tamaño de la HU. No se observaron diferencias significativas de la prevalencia de HU entre sexos (c2 1 =0.26; P=0.61), aunque las hembras presentaron un riesgo relativo mayor (1.27) que los machos. El tamaño del anillo herniario fue menor en las hembras (8.69%) que en los machos (21.75%) (c2 1 =1.77; P=0.18). Se concluye que según el análisis de la genealogía de la familia podría ser una enfermedad oligogénica en la que estarían interactuando varios genes