Growth, Mortality, Sexual Maturity and Exploitation Level of the Golden African Snapper (Lutjanus fulgens, Lutjanidae) in Ghanaian Waters

The golden African snapper, Lutjanus fulgens, is one of the most commercially important demersal species exploited by commercial fishers along the coast of Ghana. Growth and mortality as well as aspects of reproduction of L. fulgens were studied to contribute to the paucity of biological information on the species in Ghanaian waters. Samples were collected along the coast of Ghana from September 2018 to August 2019. Total lengths of L. fulgens sampled ranged between 16.2 and 45.6 cm. Length-weight relationship of the species showed isometric growth pattern. The asymptotic length (L∞), growth coefficient (K) and age at zero length (to) for L. fulgens were estimated as 51.09 cm, 0.47 yr-1 and -0.301yr respectively. Total (Z), fishing (F) and natural (M) mortality rates of L. fulgens were estimated at 2.69 yr-1, 1.91 yr-1 and 0.78 yr-1 respectively. The length-at-first capture (Lc) = 31.51 cm, was slightly lower than the length-at-first maturity (Lm) = 33.7 cm for females. The exploitation ratio (E = 0.71) of the stocks in Ghanaian waters was above the optimal exploitation levels. Peak spawning period was observed from July to September. Mean fecundity was estimated to be 77,833 ± 13,012 eggs (mean ± SE). There was no significant difference observed in the sex ratio between males and females. The findings suggest the stocks are under high fishing pressure and so it is recommended that to avoid exploiting the spawning biomass, closed season could be observed during the spawning periods

Innovative concepts of Integrated Solar Combined Cycles (ISCC) using a Solid Oxide Fuel Cell (SOFC)

Concentrating Solar Power (CSP) is one of the most promising ways for electricity production of the upcoming years with high penetration of intermittent renewable energy sources such as wind and solar-photovoltaics. This is due to the fact that CSP when coupled to Thermal Energy Storage (TES) system enables large, inexpensive and flexible energy dispatch, which contributes to energy grid stabilization. At the same time, TES allows for steady operation of the power block by reducing undesirable fluctuations due to weather transient conditions and increasing the number of hours that the power block operates at design conditions 1. Despite the abovementioned advantages of CSP systems, a step further is needed for increase overall system efficiency and decrease CO2 emissions. Several studies have been performed considering high efficiency plant layouts such as combined cycle. For the latter, several works have been investigated about solar integration of combined cycle using parabolic trough and solar tower technologies. In both cases, solar energy was used for water/steam preheating and evaporation steps of the Rankine cycle in combination with the exhaust gases of fossil-fuel gas turbine engine. However, no research has been performed considering ISCC coupled with a Solid Oxide Fuel Cell (SOFC). In this research, two innovative layouts of ISCC power plants will be analyzed. First considers a ISCC based on solar tower and second a ISCC with a parabolic trough collector field coupled to the Heat Recovery Steam Generator (HRSG). The objective of this research is analyze the energy behavior of both layouts, selecting the best ISCC scheme to be coupled with a SOFC. The simulations will be performed using Thermoflex software. In both layouts, a SOFC is introduced before the combustion chamber at the topping cycle, and a Rankine cycle (bottoming cycle) with 2 pressures is considered.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Métodos de reducción de escala : aplicaciones al tiempo, clima, variabilidad climática y cambio climático

Los Modelos de Circulación General Atmosféricos-Oceánicos Acoplados muestran buena habilidad para simular la evolución de las circulaciones de escala global. Sin embargo, esta bondad no es muy útil para el estudio de impactos locales debido a que la resolución espacial de esos modelos está por encima de la escala de los impactos locales que se desean analizar. Es importante tomar esto en cuenta al estudiar impactos del clima en las actividades del hombre, en la biodiversidad, en ambientes marino-costeros y en arrecifes en las regiones tropicales, por ejemplo. Existen dos aproximaciones para lidiar con esta diferencia de escala e información: los métodos de reducción de escala dinámica y estadística. En este trabajo, se discuten los elementos básicos del sistema climático y las posibles causas de los cambios atmosféricos observados en este sistema. Se discuten brevemente los principales conceptos físicos del sistema climático, el clima de una región, la variabilidad climática y las generalidades del problema del cambio climático global con énfasis en el aspecto regional del mismo. Se describen también los esquemas metodológicos del proceso de reducción de escala y se presenta una discusión sobre sus ventajas y limitaciones, así como algunas aplicaciones al tiempo atmosférico y clima regional.Coupled Atmosphere-Ocean General Circulation Models demonstrate good skill in simulating large scale circulations. However this output is not very useful to study local impacts, as its spatial resolution is courser than the scale of local impacts. It is very important to consider this issue when studying, for instance, climate impacts on human activities, coastal-marine biodiversity and tropical coral reefs. In general terms, there have been two different approaches to deal with this scale and information difference: the dynamic and the statistic downscaling methods. In this work, the basic climate elements are presented and the possible physical causes of atmospheric changes are discussed. Also, a summary of the main physical concepts that define the climate system as well as the climate and climate variability of a region with respect to the mean atmospheric state and the general aspects of the problem of climate change with emphasis on regional scales, is presented. In addition, this study describes the methodological schemes of the downscaling process and presents a discussion of downscaling advantages and disadvantages, while providing applications for regional weather and climate as well as for socio-economic benefits in coastal, agricultural and tourism activities, among others

A systematic review and critical appraisal of quality indicators to assess optimal palliative care for older people with dementia

© The Author(s) 2019Background: A challenge for commissioners and providers of end-of-life care in dementia is to translate recommendations for good or effective care into quality indicators that inform service development and evaluation. Aim: To identify and critically evaluate quality indicators for end-of-life care in dementia. Results: We found 8657 references, after de-duplication. In all, 19 publications describing 10 new and 3 updated sets of indicators were included in this review. Ultimately, 246 individual indicators were identified as being relevant to dementia end-of-life care and mapped against EAPC guidelines. Conclusions: We systematically derived and assessed a set of quality indicators using a robust framework that provides clear definitions of aspects of palliative care, which are dementia specific, and strengthens the theoretical underpinning of new complex interventions in end-of-life care in dementia.Peer reviewedFinal Published versio

Response of Nitrous Oxide Flux to Addition of Anecic Earthworms to an Agricultural Field

The burrowing and feeding activities of earthworms may have a strong effect on the flux of N2O from agricultural soils. As such, shifts to agricultural management practices that increase the number of earthworms require an understanding of the role of earthworms in N2O dynamics. We conducted a field experiment to examine the effects of addition of anecic earthworms (Lumbricus terrestris) on N2O flux in a field previously planted with corn (Zea mays) in southern Rhode Island, USA. Plots were amended with (15NH4)2SO4 and either 0 (CTL) or 48 L. terrestris m-2 (EW). The flux of N2O, 15N2O and 15N2 was measured over 28 days between October and November 2008. The EW treatment had a significantly higher flux of N2O and 15N2O 1 - 3 days after 15NH4 addition. No treatment effects were observed on 15N2 flux. The addition of earthworms significantly increased (Day 1) and decreased (Day 12) the mole fraction of N2O relative to the CTL. Our results suggest that anecic earthworm additions can increase N2O flux from inorganic fertilizer N amendments, but the effects appear to short-lived

Factors associated with extended remission in neovascular age-related macular degeneration on pro re nata treatment protocol.

AimTo show the characteristics and outcomes of patients with neovascular age-related macular degeneration (nAMD) who had extended remission (ER) while on a pro re nata (PRN) treatment protocol.MethodsThis was a retrospective case-control study of a consecutive series of patients with nAMD treated with a PRN antivascular endothelial growth factor (anti-VEGF) drug regimen. ER was defined as the absence of haemorrhage, intraretinal/subretinal fluid on optical coherence tomography and leakage on fluorescein angiography for 52 weeks after cessation of anti-VEGF therapy. Matching patients with nAMD who did not achieve ER were included as control group. Cox regression analysis was fitted to identify predictors of time to achieve ER and time to recurrence. A logistic regression analysis of baseline characteristics was used to identify predictors of achieving ER.ResultsOf 830 eyes treated with anti-VEGF monotherapy, 77 (9.2%) eyes achieved ER during a median follow-up of 236 weeks (range 70-525 weeks). Cox regression analysis showed that ER was achieved earlier in eyes with isolated intraretinal fluid (HR, 2.05; 95% CI 1.929 to 4.520; p=0.045) at presentation. Logistic regression analysis showed that type 3 choroidal neovascularisation (OR, 0.090; 95% CI 0.021 to 0.382; p=0.001), thinner choroid (OR, 0.993; 95% CI 0.988 to 0.998; p=0.004) and absence of macular atrophy (OR, 0.233; 95% CI 0.065 to 0.839; p=0.026) at baseline increased the likelihood of achieving ER.ConclusionER is achievable in 9.2% of patients under PRN therapy for nAMD. At presentation with nAMD, anatomical features on retinal imaging may predict the likelihood of achieving ER and a shorter time to achieve ER

Spin-dependent electronic conduction along zigzag graphene nanoribbons bearing adsorbed Ni and Fe nanostructures

Using SMEAGOL, an ab initio computational method that combines the non-equilibrium Green's function formalism with density-functional theory, we calculated spin-specific electronic conduction in systems consisting of single Fen and Nin nanostructures (n = 1−4) adsorbed on a hydrogen-passivated zigzag graphene nanoribbon. For each cluster we considered both ferromagnetically and antiferromagnetically coupled ribbon edges (Ferro-F and Ferro-A systems, respectively). Adstructures located laterally on Ferro-A ribbons caused significant transmittance loss at energies 0.6–0.25 eV below the Fermi level for one spin and 0.2–0.4 eV above the Fermi level for the other, allowing the potential use of these systems in transistors to create a moderately spin-polarized current of one or the other sign depending on the gate voltage. Ni₃ and Ni₄ clusters located at the centre of Ferro-F ribbons exhibited a strong spin-filtering effect in a narrow energy window around the Fermi level

Depuración genética de poblaciones mediante marcadores diagnóstico

La pérdida de diversidad genética, que conlleva descensos en eficacia biológica y pérdida de adaptabilidad, suele considerarse un fenómeno a evitar. Sin embargo determinadas poblaciones requieren la preservación del fondo genético diferenciado de otros grupos: han de ser mantenidas en pureza. El motivo puede ser económico: razas que proporcionan productos de interés (como los cerdos ibéricos o bovinos de raza Reggiana; Dalvit et al., 2007) razas, como en perros, que no se cruzan por motivos estéticos (Parker et al., 2004), etc. También en especies o razas salvajes amenazadas por su equivalente doméstico tiene interés el mantenimiento de su base genética diferenciada (Rhymer y Simberloff 1996; Allendorf et al., 2001). Si tenemos una población de interés que se ha cruzado (bien por error o por mala gestión) con otra y queremos recuperar su fondo genético original, tendremos que llevar a cabo un proceso de desintrogresión. Por ejemplo, poblaciones que quieren recuperarse a través de un banco de semen requieren la utilización de hembras de otra población cuyo fondo genético habría de ser eliminado (Hall y Bradley 199