Search

In the framework of global human-induced change, marine communities' often respond to changing conditions abruptly reorganizing into new equilibria. These shifts are difficult to predict and often imply irreversible adjustments due to hysteresis. Unraveling the role of the forces leading regime shifts is a major challenge. We explored the temporal evolution of 63 fish species representing the Cantabrian bentho-demersal community in response to environmental changes and fishing pressure in the period 1983–2018, using survey data. Via multivariate analysis and non-additive modeling of a community index and the system's main stressors, two decadal-scale regimes were revealed, suggesting a non-linear response of the community to its environment. The Integrated Resilience Assessment framework elucidated the response mechanism to the candidate stressors and allowed quantifying resilience dynamics. The decline in fishing pressure in the 1990s was associated with a gradual transition of the system, while further decline during the 2000s eroded the resilience of the system towards changes in its stressors, leading to a discontinuous response expressed as an abrupt, possibly irreversible shift in the 2010s. Given the teleconnected character of marine ecosystems, this regional study endorses the scientific effort for actions facing the dynamic impacts of climate change on exploited marine ecosystems. [ABSTRACT FROM AUTHOR]

Abstract Electrical energy production using renewable energies is one of the most important challenges in recent years. Among renewable energies, it is worth highlighting photovoltaic and thermoelectric systems due to their adaptation to the Canary Islands. One of the most important issues to ensure the stability for solar power systems, mostly in insular grids as Canary Islands, is the precise knowledge of solar radiation. In this paper, we focus in Gridded Satellite data suitability for modelling Global Horizontal Irradiation (GHI) in islands with complicated orography, as Canary Islands. Solar radiation data retrieved from CM SAF and McClear model were analysed and compared with 22 ground measurement stations in Canary Islands. Moreover, this analysis presents the results of including a site-adaptation methodology for improving satellite suitability. We used different procedures to perform this site adaptation depending on the solar radiation conditions (clear sky or cloudy sky hours), the location of the measurement station (we establish two clusters according to the climate conditions) and the season. This study could provide information about satellite models suitability in islands and a better knowledge of solar radiation behavior. Furthermore, accurate satellite radiation data for wide spatial and temporal coverage could improve solar radiation modelling and forecasting. Highlights • Assessment of CM SAF satellite derived solar radiation data and clear sky models in islands. • Selection of clear sky hours and clustering of the region to obtain optimal site adaptation. • Discussion of satellite assessment and proposal a site-adaptation. [ABSTRACT FROM AUTHOR]

PV systems generally need measurements of incident solar irradiance for the analysis of the performance and for monitoring purposes. Solar irradiance for PV monitoring is normally measured either by thermopile pyranometers or by calibrated crystalline silicon solar cells. While thermopile pyranometers are the most accurate sensors there are some advantages and shortcomings on the use of reference cells that need to be studied. In the case of small scale PV arrays, such as rooftop PV systems, the much higher costs of pyranometers would recommend the use of other devices for monitoring the incident irradiance. In this work five different small-scale PV arrays have been monitored and modelled using solar tilted irradiance data measured by a pyranometer and by two different PV modules in short circuit conditions. The Sandia Array Performance Model has been used to evaluate the impact of using standard PV modules as irradiance sensors in modelling the performance. The results have shown higher accuracy of the model when CdTe module in short circuit is used as irradiance sensor. The use of just one PV module for monitoring the irradiance instead of for delivering energy can be an interesting choice in the case of small PV arrays. [ABSTRACT FROM AUTHOR]

The capabilities of modelling the performance of photovoltaic (PV) systems depend both on the available PV models and on the accuracy of the input information that the models need. The meteorological input to any model consists mainly of the solar irradiance incident in the module as well as other influencing variables (temperature, wind speed, etc.). Since incident solar irradiance on characteristic inclined surfaces is not frequently available, the performance models use to incorporate specific models for computing tilted solar irradiance from the other components (global horizontal and direct normal) with higher availability. In this work, System Advisor Model (SAM), a performance model, has been used to analyze the contribution of some well-known transposition models to the uncertainty in modelling the system performance. The study has been performed for a small-scale photovoltaic array of CdTe placed at the roof of a building in Madrid. The performance predicted by SAM is rather good with around 3% of root mean squared error in the daily AC power when the input irradiance is taken from experimental measurements at the modules tilt angle. A 3% of an additional error increase compared to the results with the experimental tilt irradiance was observed for using all of the transposition models included in SAM. [ABSTRACT FROM AUTHOR]

At any site, the bankability of a projected solar power plant largely depends on the accuracy and general quality of the solar radiation data generated during the solar resource assessment phase. The term “site adaptation” has recently started to be used in the framework of solar energy projects to refer to the improvement that can be achieved in satellite-derived solar irradiance and model data when short-term local ground measurements are used to correct systematic errors and bias in the original dataset. This contribution presents a preliminary survey of different possible techniques that can improve long-term satellite-derived and model-derived solar radiation data through the use of short-term on-site ground measurements. The possible approaches that are reported here may be applied in different ways, depending on the origin and characteristics of the uncertainties in the modeled data. This work, which is the first step of a forthcoming in-depth assessment of methodologies for site adaptation, has been done within the framework of the International Energy Agency Solar Heating and Cooling Programme Task 46 “Solar Resource Assessment and Forecasting”. [ABSTRACT FROM AUTHOR]

Feasibility analysis for CSP projects requires quantifying the economic risk associated with the inter-annual variability of the solar resource and uncertainties in the annual energy production estimates. To assess this risk, statistical methods may be applied either before the system simulation (e.g. to create solar resource data in terms of exceedance probabilities such a P50 or P90) or on the system performance to determine the likelihood that a power plant will generate a certain amount of energy in any given year over the plant's life (e.g. the P50 or P90 annual productions). This paper presents and illustrates the long-term analysis of four CSP plants (parabolic trough and central receiver technology) in four sites within the Mediterranean and North Africa region; the analysis includes the exceedance probabilities estimations. Satellite-derived data for 20 years have been used for solar resource datasets in hourly basis, and multiyear simulations of the plant output have been performed with System Advisor Model. The associated uncertainties have been included in the long-term analysis of both DNI and CSP plant production. The results remark the advantages of multiyear analysis of CSP output for long-term analysis against the use of artificial meteorological years which represent the long-term. [ABSTRACT FROM AUTHOR]

Evaluation and validation of photovoltaics performance models for different technologies and climate regions is of high interest for photovoltaic (PV) systems deployment. There are many tools for modelling the performance of PV arrays; some of them are free or open source. This work presents the results of modelling five different rooftop PV arrays in the range of 1 kW using the Sandia Array Performance Model during one complete year in Madrid. The evaluation of the Sandia model has shown a rather good performance in general, even though several empirical parameters in the input were unknown and were taken from other similar modules in the Sandia database. Particularly, high accuracy has been found in modelling the p-Si array with -0.07% of relative error in the annual energy output. Larger errors were found in the case of a-Si and m-Si (back contact) arrays. [ABSTRACT FROM AUTHOR]

Solar radiation derived from satellite imagery is a powerful and highly accurate technique for solar resource assessment due to its maturity and to the long term database of observation images available. This work presents the methodology developed at CIEMAT for mapping solar radiation from geostationary satellite information and it also shows solar irradiation maps of global horizontal and direct normal components elaborated for Spain. The maps presented here have been developed from daily solar irradiation estimated for eleven years of satellite images (2001–2011). An attempt to evaluate the uncertainty of the presented maps is made using ground measurements from 27 meteorological stations available in Spain for global horizontal irradiation obtained from the World Radiation Data Centre. In the case of direct normal irradiation the ground measurement database was scarce, having available only six ground stations with measurements for a period of 4 years. Yearly values of global horizontal irradiation are around 1800 kWh m −2 in most of the country and around 1950–2000 kWh m −2 for annual direct normal irradiation. Root mean square errors in monthly means were of 11% and of 29% for global horizontal and direct normal irradiation, respectively. [ABSTRACT FROM AUTHOR]

A simple method for correcting satellite-derived direct normal irradiance, with important deviations to the experimental data, is presented in this work and illustrated for the particular case of Rajasthan (India). Northwest India is expected to have a high level of solar radiation and it is an interesting area for solar concentrating power systems. However uncertainty in direct normal irradiance estimations from satellite may affect negatively to the bankability of solar plants. Direct normal irradiance have been estimated for a site in Rajasthan from satellite information for the period 2003 to 2011, and ground measurements during 2011 have been used to analyze the uncertainties and to develop a simple correction method. The original satellite estimations showed important deviations from the experimental values and high bias. A systematic underestimation of direct irradiance has been observed during the dryer seasons that could be attributed to an overestimation of the aerosol optical depth input to the model. These observations have allowed the design of a correction methodology. Unbiased new estimations of direct normal irradiance have been generated with this methodology with important reduction in the deviations and with an agreement in the distribution functions compared to the distribution function of the ground data. [ABSTRACT FROM AUTHOR]

The present paper presents maps of the solar resources in Vietnam and of the solar potential for concentrating solar power (CSP) and for grid-connected photovoltaic (PV) technology. The mapping of solar radiation components has been calculated from satellite-derived data combined with solar radiation derived from sunshine duration and other additional sources of information based on reanalysis for several atmospheric and meteorological parameters involved. Two scenarios have been selected for the study of the solar potential: CSP Parabolic Trough of 50 MWe and grid-connected Flat Plate PV plant of around 1 MWe. For each selected scenario plant performance simulations have been computed for developing simple expressions that allow the estimation of the solar potential from the annual solar irradiation and the latitude of every site in Vietnam. Finally, Geographic Information Systems (GIS) have been used for combining the solar potential with the land availability according each scenario to deliver the technical solar potential maps of Vietnam. [ABSTRACT FROM AUTHOR]

The accurate quantification of direct normal irradiance (DNI) and the production of time series of DNI have a key role during the planning and designing stages of CSP plants. Satellite derived data are frequently used for that purpose. One of the important sources of uncertainty for satellite derived DNI is the accuracy in the quantification of aerosol optical depth, one of the most important parameters that contribute to solar radiation attenuation at the Earth’s surface. This topic can be extremely important in desert and arid places where sudden and large increase of aerosol optical depth can be eventually expected. This work presents an analysis of the uncertainty about the knowledge of aerosol optical depth in Sede Boqer and Tamanrasset, its contribution to the uncertainty of DNI values estimated from Meteosat imagery, and finally the impact on the CSP plant energy dispatched. Reference plants for CSP parabolic trough and CSP tower technologies have been modelled with SAM with no thermal storage system, and a GEMASOLAR plant-type has been also modelled as an example of tower plant with large thermal storage system. The results have shown that in Tamanrasset the sudden and eventual high peaks of aerosol optical depth resulted in an important decrease of the daily energy produced by the plant; this reduction is not always observed when satellite derived DNI is used to input meteorological conditions in SAM due to the underestimation of the aerosol optical depth. The use of large thermal storage system notably reduces the impact of these phenomena on the CSP power plant output. [ABSTRACT FROM AUTHOR]

A study on the spatial variability of long term solar radiation in Vietnam and the results of clustering solar radiation into different regions are presented here. Vietnam has a dense and long network of sunshine duration measurements, and on the contrary the country has a scarce availability of solar irradiance measuring sites. The variability of long term solar radiation can be analyzed by determining daily global irradiation from sunshine duration. A model inspired in Angstrom equation has been developed using the canonical correlation analysis with good performance. The output of the model has been used for characterizing the dispersion of long term solar radiation and its spatial distribution has been also studied by clustering techniques. The comparison with the Köppen climatic information remarks that Vietnam could be divided into 3–4 well defined zones of different solar radiation variability. [ABSTRACT FROM AUTHOR]

A new stochastic model to describe atmospheric attenuation from yearly global solar irradiation has been developed and implemented. The proposed model takes into account the consideration that the whole of all attenuating elements can be thought of as a population where the higher the number of individuals the lesser the clearness index. Thus, the inverse of the clearness index is considered as the variable of a stochastic process. From the proposed master equation as starting point, the new model is characterized by transition rates (assessed from a growing parameter - G - and a decreasing parameter - D ) which depend mainly on the climatological characteristics at each location. In this sense, different regions with an attenuation level calculated from the yearly global irradiation have been established using the Köppen–Geiger climate classification as a first approach. The model parameters G and D have been determined for different regions using the inverse of the clearness index as variable. The probability density function obtained after the application of the stochastic model for each climate zone shows how the index mode increases from the zones with lower levels of attenuation to those with higher levels of attenuation. This result confirms the proposed null hypothesis related to the use of the inverse of the clearness index as an attenuation population indicator. The fit between the empirical data and the data provided for the model is good enough according to a Kolmogorov–Smirnov test with a significance level of 0.05. Nevertheless, it is necessary to slightly modify the climate zones of Köppen–Geiger initial classification for a better explanation of the atmospheric attenuation. This climate zones modification can be considered as an additional result. [ABSTRACT FROM AUTHOR]

The monthly mean variation of the solar global reaching the Earth's surface has been characterized at a global level by a regression model. This model considers the monthly variation itself (to different horizons and even the maximum annual variation) as the study variable, and it is applied without using data corresponding to measured meteorological variable. Two explicative variables have been used, the variation of the extraterrestrial irradiation and the variation of the clear sky global horizontal irradiation. The work has been carried out from datasets including average global daily solar irradiation for each month of the year measured on the ground. The model quality has been proven to be very dependent of the temporal variation considered, in such a way that higher variations, that is to say, higher distances between months, lead to an improvement in the model outcomes. [ABSTRACT FROM AUTHOR]

Background Our purpose was to review our kidney transplantation program based on the use of expanded criteria donors, and to determine current indications for dual kidney transplantation (DKT). In 1996, a program was initiated to transplant kidneys from donors of over 60 years performing single or dual transplantation. Methods In 1996, a program was initiated to transplant kidneys from donors of over 60 years performing single or dual transplantation. DKT were performed with donors >75 and donors between 60 and 74 years of age and glomerulosclerosis of >15%. The kidneys of donors between 60 and 74 years of age and with glomerulosclerosis of <15% were used for single kidney transplantation (SKT). In 2005, we started to perform SKT despite glomerulosclerosis being >15%, taking into account donor and recipient characteristics. Results From 1996 to 2004, 222 SKTs and 88 DKTs were performed. Graft survival after 1 and 4 years was, respectively, 91% and 78% for SKT and 95% and 79% for DKT. In 2005, we started to perform SKT despite glomerulosclerosis being >15%, taking into account donor and recipient characteristics. From 2005 to 2011, 328 SKT and 32 DKT were performed. During this period most kidneys used for DKT were from female donors >75 years old, weighing <65 kg, with a creatinine of >1 mg/dL and glomerulosclerosis of >15%. The recipients for DKT were mostly male, <70 years old and whose weight was >75 kg. Conclusion DKT from expanded criteria donors shows good outcomes. However, in many cases SKT may fulfill the need of the recipient. The archetype for DKT is an older female weighing <65 kg and the most common recipient is an overweight male who is <70 years old. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a sensitivity analysis of satellite-based methods for deriving solar irradiance components for analyzing the impact of the external inputs that are normally associated to the satellite model. Different sensitivity calculations have been performed using as reference site the PSA (Solar Platform of Almeria) station placed at the south-east of Spain. Thus, the sensitivity to the aerosol information input has been addressed by comparing the estimations using aerosol input from AERONET data with those using aerosol dataset such as MODIS or MISR (based on satellite) and MACC (based on reanalysis). Sensitivity to the clear sky model choice has been also studied by using three different models, from the simpler ESRA model (in terms of input parameters) to the most sophisticated REST2. Finally, three global to direct conversion models (Louche, DirInt and DirIndex) have been included to explore the sensitivity of the direct normal irradiance estimations. The sensitivity analysis has shown the interrelations between the different cases according to the uncertainty of the input information used. The results have been analyzed for clear and non-clear sky conditions separately and for the DNI irradiance range of 400–900 W m−2 as a case of special interest for the concentrating solar power applications. The work presented here has as novelty the analysis of the propagation of uncertainty of individual models and atmospheric datasets in the framework of a satellite-based model for solar irradiance computation and their relative weights to the final performance of the model. An underestimation of AOD by 50% causes an error in the global horizontal irradiance calculated by a clear sky model of 3–5% depending on the model used, and slightly less for an overestimation of AOD. For DNI the error ranges are 12–15% and 9–12% for 50% underestimation and overestimation of AOD respectively. [Copyright &y& Elsevier]

Abstract: This paper deals the study of variability and intermittency of solar irradiation using an analogy with the turbulence and thus making use of some methodologies used in the study of intermittency of the turbulence. An analysis of the shape of the PDFs corresponding to the increments in the clearness and transmittance indexes, for direct and global radiations, is presented. In addition a study of the relations between the scaling exponents of the structure functions of the clearness and transmittance indexes and the orders of these structure functions has been carried out. According to the study, the range of relative variability is due to changes in the atmospheric components that play a role in the attenuation of solar irradiation. This range of variability is higher in the case of the global irradiation than in the case of the direct. Moreover, the multifractality is showed more intense in sites where, due to local effects, sharper variations in the radiation can be expected, as the case of deserts. [Copyright &y& Elsevier]

Abstract: Sequences of two consecutive days of solar irradiation (global horizontal and direct normal) have been studied here by different approaches. The frequency vs. rank relationships have been analyzed as an attempt to explore whether the Zifp's law is fulfilled, yielding to a partial fulfillment and observing that a good logarithmic fit can be applied to the data in the whole range. In addition, the pdfs of increments in two consecutive daily irradiation values are also studied, showing a relationship between persistence and the coefficients of the logarithmic fit. Finally, it has been shown that a Markov process can represent properly sequences of two consecutive daily irradiation values, for both global horizontal and direct normal components. Thus, synthetic series can be generated by Markov chains for characterizing daily global and direct irradiation. [Copyright &y& Elsevier]

A comparison of the DirIndex model for computing direct normal solar irradiance from global horizontal using different clear sky transmittance models is presented for four ground stations that belong to Baseline Surface Radiation Network (BSRN) and Aerosol RObotic NETwork (AERONET) networks. The results of DirInt model, which does not include any clear sky transmittance contribution, are also shown. The input for the different clear sky models selected (European Solar Radiation Atlas (ESRA), SOLar Irradiance Scheme (SOLIS) simplified, and Reference Evaluation of Solar Transmittance, 2 bands (REST2)) was generated from the original aerosol optical depth and water vapour measurements provided by AERONET. The results show different trends in the performance of the DirIndex model combined with the clear sky methods. An attempt to correct the trends to the proper one is finally proposed here and the improvement achieved is shown. [ABSTRACT FROM AUTHOR]

Objectives of this study were to develop a rapid calf-side test to determine serum IgG concentrations using caprylic acid (CA) fractionation, followed by refractometry of the IgG-rich supernatant and compare the accuracy of this method with results obtained using refractometry using raw serum. Serum samples (n = 200) were obtained from 1-d-old calves, frozen (-20°C), and shipped to the laboratory. Samples were allowed to thaw for 1 h at room temperature. Fractionation with CA was conducted by adding 1 mL of serum to a tube containing 45, 60, or 75 µL of CA and 0.5, 1.0, or 1.5 mL of 0.06 M acetic acid. The tube contents were mixed well, allowed to react for 1 min, and then centrifuged at 3,300 x g for 0, 10, or 20 min at 25°C. The %Brix and refractive index of the fractionated supernatant were determined using a digital refractometer. Nonfractionated serum was analyzed for %Brix (BRn), refractive index (nDn), and IgG concentration by radial immunodiffusion. The mean serum IgG concentration was 19.0 mg/mL [standard deviation (SD) = 9.7], with a range of 3.5 to 47.0 mg/mL. The mean serum BRn was 8.6 (SD = 0.91), with a range of 6.8 to 11.0. The mean serum nDn was 1.34566 (SD = 0.00140), with a range of 1.34300 to 1.34930. Serum nDn was positively correlated with IgG concentration (correlation coefficient = 0.86; n = 185). Fractionated samples treated with 1 mL 0.6 M acetic acid and 60 µL of CA and not centrifuged before analysis resulted in a strong relationship between the refractive index of the fractionated supernatant and IgG (correlation coefficient = 0.80; n = 45). Regression was used to determine cut points indicative of 10, 12, and 14 mg of IgG/mL to determine the sensitivity and specificity of refractometry to identify failure of passive transfer (serum IgG <10 mg/mL at 24 h old). The nDn were 1.34414, 1.34448, and 1.34480 to predict 10, 12, and 14 mg of IgG/mL of serum, respectively. The BRn cut points were 7.6, 7.8, and 8.0, respectively. The nDn cut points of 1.34448 and 1.34480 resulted in similar specificities (82.9%), whereas the 1.34414 cut point had a specificity of 60.0%. The BRn cut point of 7.6 and 7.8%Brix resulted in a similar percentage of correctly classified samples (89.7 and 90.8%, respectively); however, the 7.8% Brix cut point resulted in fewer false positives. These results suggest that Brix refractometry of nonfractionated calf serum provides a strong estimate of IgG concentration and 7.8% Brix may be used as the cut point to identify failure of passive transfer in 1-d-old calves. [ABSTRACT FROM AUTHOR]

Highlights: [•] Albedo angular dependence is studied for different geostationary satellites. [•] Ground albedo is a key parameter for solar radiation derived from satellite. [•] Solar radiation estimations from satellite should account for this angular dependence. [•] Use of two overlapping satellites improves solar radiation retrieval. [Copyright &y& Elsevier]

Neutralizing antibodies (NA) inherently present in pooled plasma collected at commercial abattoirs may provide some protection against potential porcine circovirus type 2 (PCV2) infectivity of plasma. Moreover, these NA may also contribute to the biosafety of spray-dried porcine plasma (SDPP). The objective of the study was to characterize and quantify the PCV2 antibody neutralizing capacity in pooled liquid porcine plasma and SDPP samples collected from industrial spray-drying facilities located in the Southeast and Midwest regions of the United States and the Northeast region of Spain. In the United States, PCV2 NA was determined in 1 sample of pooled liquid plasma from commercial spray-drying plants in the Southeast and 1 from the Midwest region. Obtained results were compared with those of a plasma sample from a PCV2 vaccinated sow and 1 from a PCV2 antibody negative sow. In Spain, 15 pooled liquid porcine plasma samples and 10 SDPP samples were collected at a commercial spray-drying plant total and NA against PCV2 were determined. Results with pooled liquid porcine plasma from commercial spray-drying facilities in the United States indicated that NA titers against PCV2 in these samples (log2 8.33 ± 0.41 and 9.0 ± 0.0) were similar or greater than the plasma from the PCV2-vaccinated sow (log2 6.33 ± 0.41). The analysis of U.S. samples indicated that liquid plasma diluted to 1:256 (10<-2.41) was able to neutralize between 100 to 200 PCV2 virus particles or about 4 logs10 median tissue culture infective dose (TCID50) per milliliter. Similarly, samples from the Spanish pooled liquid plasma and the SDPP samples indicated an increased amount of NA activity against PCV2. Specifically, a dilution of 10-2.47±0.33 of plasma was able to inactivate 100 PCV2 virus particles; therefore, the inactivation capacity of commercial liquid plasma was greater than 104 TCID50/mL. The calculated 90% reduction in infected cells because of NA in pooled plasma samples (log2 8.2 ± 0.38) was less (P < 0.05) than in its concentrate form of SDPP (mean, log2 10.2 ± 0.85). In conclusion, PCV2 NA contained in liquid pooled plasma from market pigs was detected at greater concentrations than that from a vaccinated sow and that after spray-drying biological neutralizing activity was conserved, which implies that the inherent NA in liquid plasma may have an important role in the biosafety of commercially produced SDPP. [ABSTRACT FROM AUTHOR]

AbstractMild traumatic brain injury (mTBI), particularly mild “blast type” injuries resulting from improvised exploding devices and many sport-caused injuries to the brain, result in long-term impairment of cognition and behavior. Our central hypothesis is that there are inflammatory consequences to mTBI that persist over time and, in part, are responsible for resultant pathogenesis and clinical outcomes. We used an adaptation (1 atmosphere pressure) of a well-characterized moderate-to-severe brain lateral fluid percussion (LFP) brain injury rat model. Our mild LFP injury resulted in acute increases in interleukin-1α/β and tumor necrosis factor alpha levels, macrophage/microglial and astrocytic activation, evidence of heightened cellular stress, and blood–brain barrier (BBB) dysfunction that were evident as early as 3-6 h postinjury. Both glial activation and BBB dysfunction persisted for 18 days postinjury. [ABSTRACT FROM AUTHOR]

Abstract: Methodologies for computing ground albedo from geostationary satellite images are investigated within the framework of models for deriving solar radiation components from satellite information. A revision of Heliosat-3 approach for determining ground albedo and its implication in the cloud index estimation is done using two close pixels of quite different reflectivity in the Nile delta surroundings in Egypt. The analysis done has revealed that the way in which Heliosat-3 approaches the ground albedo and especially its dependence with the viewing angle is not very precise when dealing with high reflective sites. A simple method for fitting, individually for every pixel, the angular dependence and the ground albedo estimations is proposed here and applied to different points in the Mediterranean area. The results of the revised method show rather good estimations of ground albedo in every kind of terrain in terms of reflectivity. These results are translated to cloud index estimations and finally to surface solar irradiance and they show improvements in solar radiation estimation over high reflective pixels. [Copyright &y& Elsevier]

Abstract: Exposure to hypoxia and hyperoxia in a rodent model of perinatal ischemia results in delayed cell death and inflammation. Hyperoxia increases oxidative stress that can trigger inflammatory cascades, neutrophil activation, and brain microvascular injury. Here we show that 100% oxygen resuscitation in our rodent model of perinatal ischemia increases cortical COX-2 protein levels, S-nitrosylated COX-2cys526, PGE2, iNOS and 5-LOX, all components of the prostaglandin and leukotriene inflammatory pathway. [Copyright &y& Elsevier]

Abstract: India is endowed with good solar energy resource due to its geographic position in the equatorial Sun Belt of the earth, but its atmosphere can have eventual large presence of aerosols with the subsequent negative feedback to the solar radiation available. Therefore, solar resource assessment studies over India are of high interest for potential solar energy applications. In this work daily estimations of global horizontal and direct normal irradiation are presented for six locations in India covering the years from 2000 till 2007. These computations have been performed with IrSOLaV/CIEMAT method for computing solar radiation components from Meteosat images with a spatial resolution of less than 5×5km. A brief assessment exercise of the model output have been made with ground measurements available from the World Radiation Data Centre database, which consists only of daily sums of global horizontal irradiation. The daily global horizontal irradiation estimated by the model has shown a general positive bias with the ground measurements in the range of 5%, being the root mean square deviation around 12%, excepting for Trivandrum location where there are evidences of higher uncertainty in the ground measurements. In addition, the dynamical behavior of daily global irradiation is quite well reproduced by the model as a consequence of adding to the input the daily turbidity values estimated from MODIS Terra satellite information. Estimations of direct normal irradiation are also exposed but no assessment was made due to the lack of ground measurements. The importance and need of accurate daily aerosol data with high spatial resolution for solar radiation estimations is pointed out in this work. [Copyright &y& Elsevier]

Abstract: Modeling the performance of some concentrating solar systems for thermal power plants may require high temporal resolution irradiance as input, in order to account for the impact of the cloud transient effects. This work proposes a simple method of generating synthetic irradiance of 10-min intervals from the hourly mean values. Boundary conditions are imposed to preserve the expected behavior under clear sky situations. The procedure consists basically on adding a random fluctuation, which characteristic amplitude depends on the sky conditions, to the hourly interpolated values. The assessment of the method with ground data have shown to main aspects to remark: daily and monthly means from the synthetic data are below 5% of root mean squared deviation compared to the original time series; despite the noticeable uncertainty in the 10-min synthetic irradiance values, the dynamic behavior of the fluctuations is comparable to the original data. [Copyright &y& Elsevier]

Multiple stress events at weaning can impact intestinal barrier function and induce immune dysfunction; thus affecting piglet performance and health. Spray-dried plasma (SDP) is processed from blood and contains several functional components with biological activity independent of their nutritional value. Bovine or porcine spray-dried plasma is used in pig feed at weaning due to its well-known beneficial effects on postweaning performance and health. These positive effects of dietary SDP may be related to modulation of the inflammatory response by interacting with the intestine (GALT) to affect the systemic response. In recent studies, the effects of orally feeding bovine or porcine SDP have been demonstrated systemically in pigs challenged with porcine reproductive and respiratory syndrome virus (PRRSV) and swine influenza (SIV) and in rats injected with a bacterial toxin. In PRRSV challenged pigs, porcine SDP reduced (P < 0.05) interstitial pneumonia and viremia by d 28, which was likely modulated by increased pulmonary pro-inflammatory cytokines. In SIV challenged pigs, bovine SDP reduced (P < 0.05) lung lesions and improved gain. Porcine spray-dried plasma reduced (P < 0.05) leukocyte infiltation and pro-inflammatory cytokines in the lungs and increased (P < 0.05) anti-inflammatory cytokine in both the intestine and lungs in mice intra-nasally exposed to a bacterial toxin. Collectively, these findings indicate that orally fed bovine or porcine SDP impacts the systemic inflammatory response to improve performance and health. Therefore, addition of SDP to animal feed helps to maintain and support the immune system and growth performance when the animal is exposed to a variety of stress events. [ABSTRACT FROM AUTHOR]

Abstract: Spray-dried animal plasma (SDAP) is used in canned pet food mainly because of some technological properties such as gel strength, water retention and fat emulsion capacities. In this study, 5 different binders commonly used in canned pet food recipes were evaluated in chunk- and loaf-type products. The binders tested were SDAP, wheat gluten (WG), dehydrated pork rind (DPR), soy protein concentrate (SPC) and a newly developed product containing a mixture of plasma, globin and red cells (MIX). The binders were incorporated in the chunk and loaf recipes at 15 or 25g/kg, respectively. The inclusion of SDAP or MIX improved chunk strength with respect to the inclusion of DPR or WG with the inclusion of SPC being intermediate (P<0.001). The recipe containing WG showed the highest water loss value and those containing SDAP and MIX showed the lowest (P<0.001). Viscosity was not statistically different among binders. For loaf products the best texture was obtained with MIX inclusion followed by SDAP inclusion (P<0.001) with DPR giving the lowest quality (P<0.001). The inclusion of DPR resulted in greatest water loss than the inclusion of SDAP (P<0.05). The viscosity of raw emulsions was similar to that observed in the chunk recipes. The inclusion of MIX resulted in a lower L* and higher a* in both types of pet foods, indicating that final cooked recipe was less pale and redder than recipes that included the other binders. The differences in colour observed were still evident 60min after the opening of the can. In summary, the inclusion of SDAP and MIX improved the texture and reduced water loss in chunk and loaf foods compared with the other binders tested. The use of MIX increased the natural red colour of cooked pet foods. The DPR is an alternative binder to WG and SPC if the objective is to maintain the quality of the final product. [Copyright &y& Elsevier]

Abstract: This work presents a methodology for estimating daily Linke turbidity factor for clear sky days from global horizontal irradiance information at solar noon and monthly mean values of the Linke turbidity factor. The analysis of the method proposed here have been made using the ESRA clear sky model to recalculate the direct normal irradiance using as input the new Linke turbidities. Ground data of three BSRN and six AEMet radiometric meteorological stations have been used for assessing the method. Linke turbidity factor estimated here exhibits higher fluctuations than the monthly means and the comparison of the solar irradiance recalculated with the ground data have shown a noticeable reduction of the root mean square deviation. On the other hand the new Linke turbidity estimations have been compared to those values obtained from normal beam irradiance measures. The discrepancies found point out the high dependence of the reliability of this method with the quality of the ground measurements used. [Copyright &y& Elsevier]

Abstract: During embryonic and early postnatal development the combination of cell proliferation, migration, survival and cell death is intimately regulated. In the mouse embryo, significant numbers of primordial germ cells, the founder cells of the gametes, fail to migrate correctly to the genital ridges early in histogenesis. Studies in Bcl-2 associated X protein null mice (Bax−/−) have shown that the pro-apoptotic Bax gene is required for the programmed cell death of germ cells left in ectopic locations during and after germ cell migration. Independent studies carried out in the central nervous system of Bax−/− mice have shown impaired and ectopic neuronal migration in the cerebellum and olfactory bulb during development and in the adult hippocampus. Taken together, these evidences identify Bax as a major mechanism in ectopic cell death and are the subject of this review. [Copyright &y& Elsevier]

Decreased cerebral blood flow (CBF) has been observed following the resuscitation from neonatal hypoxic-ischemic injury, but its mechanism is not known. We address the hypothesis that reduced CBF is due to a change in nitric oxide (NO) and superoxide anion O2- balance secondary to endothelial NO synthase (eNOS) uncoupling with vascular injury. Wistar rats (7 day old) were subjected to cerebral hypoxia-ischemia by unilateral carotid occlusion under isoflurane anesthesia followed by hypoxia with hyperoxic or normoxic resuscitation. Expired CO2 was determined during the period of hyperoxic or normoxic resuscitation. Laser-Doppler flowmetry was used with isoflurane anesthesia to monitor CBF, and cerebral perivascular NO and O2- were determined using fluorescent dyes with fluorescence microscopy. The effect of tetrahydrobiopterin supplementation on each of these measurements and the effect of apocynin and Nω-nitro-L-arginine methyl ester (L-NAME) administration on NO and O2- were determined. As a result, CBF in the ischemic cortex declined following the onset of resuscitation with 100% O2 (hyperoxic resuscitation) but not room air (normoxic resuscitation). Expired CO2 was decreased at the onset of resuscitation, but recovery was the same in normoxic and hyperoxic resuscitated groups. Perivascular NO-induced fluorescence intensity declined, and Of-induced fluorescence increased in the ischemic cortex after hyperoxic resuscitation up to 24 h postischemia. L-NAME treatment reduced O2- relative to the nonischemic cortex. Apocynin treatment increased NO and reduced O2- relative to the nonischemic cortex. The administration of tetrahydrobiopterin following the injury increased perivascular NO, reduced perivascular O2-, and increased CBF during hyperoxic resuscitation. These results demonstrate that reduced CBF follows hyperoxic resuscitation but not normoxic resuscitation after neonatal hypoxic-ischemic injury, accompanied by a reduction in perivascular production of NO and an increase in O2-. The finding that tetrahydrobiopterin, apocynin, and L-NAME normalized radical production suggests that the uncoupling of perivascular NOS, probably eNOS, due to acquired relative tetrahydrobiopterin deficiency occurs after neonatal hypoxic-ischemic brain injury. It appears that both NOS uncoupling and the activation of NADPH oxidase participate in the changes of reactive oxygen concentrations seen in cerebral hypoxic-ischemic injury. [ABSTRACT FROM AUTHOR]

Uric acid (UA), a product of purine metabolism, may be an antioxidant, perhaps acting as a scavenger of peroxynitrite. Patients with gout have a reduced incidence of multiple sclerosis (MS). A number of studies found that patients with MS have low serum levels of UA, although it has not been established whether this represents a primary deficit or a secondary effect. UA has also been proposed as a marker of disease activity and response to immunosuppressive or immunomodulatory treatment. We retrospectively reviewed 83 relapsing–remitting or secondary progressive MS patients (64 females and 19 males) followed in our Neurology Unit. We collected data concerning demographic variables as age and sex, and clinical variables as age of onset, clinical type, disease duration, EDSS score and total number of relapses. We considered UA levels in three different situations: during a relapse, during remission period and during remission period under immunomodulatory treatment [Interferon Beta 1a im (Avonex; Biogen Idec Inc., Cambridge, MA, USA), Interferon Beta 1a sc (Rebif; Serono Europe Limited, London, UK), Interferon Beta 1b (Betaferon; Bayer Schering Pharma AG, Berlin, Germany) or Glatiramer Acetate (Copaxone; TEVA Neuroscience LLC, Kansas City, MO, USA)]. A Wilcoxon matched pairs test was carried out to determine differences between groups. A P-value less than 0.05 was considered statistically significant. In 33 patients, we were able to compare at least one UA value obtained during a relapse with at least one when remission without treatment. Mean serum UA levels were significantly lower when measured during a relapse ( r: 0.39, P: 0.024). In 27 cases, we compared at least one remission value without treatment with at least one obtained during remission and immunomodulatory treatment. Mean serum UA levels significantly increased when determined during Interferon Beta or Glatiramer Acetate therapy ( r: 0.84, P < 0.001). Although we do not know exactly whether and how UA is involved in MS pathogenesis, our data suggest that UA might reflect disease activity or treatment response in MS. [ABSTRACT FROM AUTHOR]

The effect of the addition of pork haem pigment on the colour, colour stability and texture of cooked hams from pale, soft and exudative meat (PSE hams) was studied. A total of 62 hams were selected at 15 h post mortem on the basis of pH, electrical conductivity (EC) and L* value in semimembranosus (SM) and biceps femoris (BF) muscles. Hams were divided into three groups to be manufactured as cooked hams: group 1 (control, with normal meat quality hams, n = 20), group 2 (control, with PSE hams, n = 21) and group 3 (with PSE hams to which 0.04% of pork haem pigment was added, n = 21). The stability of the colour (L*, a*, b*) was followed at 0, 30 and 120 mm after slicing. Pigment content and the instrumental texture of the hams were also evaluated. L* value after slicing was lower in group 3 than in group 2 for both muscles at all three times studied. Colour a* value (redness) was significantly higher for group 3 than for groups 1 and 2 at the three times and in the two muscles. Accordingly, there was an increase in visual redness in BF and SM of hams from group 3 with respect to groups 1 and 2. Iridescence was higher in PSE hams. The muscle pigment content showed no significant differences among groups — neither in the fresh nor in the cooked hams. No effect of the pork pigment was found on the texture properties studied. In conclusion, the addition of stabilised pork haem pigment in the processing of PSE hams resulted in cooked hams with lower L* values and higher a* values and more visual redness, whereas colour stability and texture of hams were not affected. [ABSTRACT FROM AUTHOR]

Abstract: Poly(ADP-ribose) polymerase-1 (PARP-1) is a DNA repair-associated enzyme that has multiple roles in cell death. This study examined the involvement of PARP-1 in ischemic brain injury in the 7-day old rat, 0.5–48h after unilateral carotid artery ligation and 2h of 7.8% oxygen. This experimental paradigm produced a mild to moderate injury; 40–67% of animals in the ligated groups had histological evidence of neuronal death. Ipsilateral cortical injury was seen at all survival times, while mild contralateral cortical injury was seen only at the 1h survival time. Hippocampal injury was delayed relative to the cortex and did not show a biphasic pattern. Immunohistochemical staining for PARP showed bilateral increased staining as early as 1h post-hypoxia. PARP staining at early time periods was most intense in layer V of cortex, but did not demonstrate a pattern of cell clusters or columns. Ipsilateral PARP-1 levels quantified by western blotting showed a biphasic pattern of elevation with peaks at 0.5 and 12h post-hypoxia. Contralateral PARP-1 levels were also elevated at 0.5 and 24h. PARP activity as determined by immunoreactivity for poly(ADP-ribose) (PAR) was increased ipsilaterally at 0.5, 2 and 12h survival times. Cortical caspase 3-activity was increased ipsilaterally at 6, 12, and 24h and contralaterally at 0.5, 1, 2 and 6h post-hypoxia. There are three main findings in this study. First, changes in the distribution and amount of cell death correlate well with measured PARP-1 levels after hypoxia–ischemia, and both display biphasic characteristics. Second, there are significant early, transient morphological and biochemical changes in the contralateral cortex after neonatal hypoxia–ischemia due to unilateral permanent occlusion of a carotid artery followed by 2h of systemic hypoxia. Third, variability in the responses of individual pups to hypoxia–ischemia suggests the presence of unidentified confounding factors. [Copyright &y& Elsevier]

Three experiments were conducted to evaluate viral inactivation by the spray-drying process used in the production of spray-dried animal plasma (SDAP). In Exp. 1, bovine plasma was inoculated with pseudorabies virus (PRV) grown in PK 15 cells. Three 4-L batches were spray-dried in the same manner and conditions of industrial SDAP production but with laboratory spray-drying equipment. Presence of infectivity was determined before and after spray-drying by microtiter assay in PK 15 cell cultures. Before spray-drying, all three samples contained 105.3 tissue culture infectious dose50 (TCID50)/mL of PRV. After four consecutive passages, no viable virus was detected in samples of spray-dried bovine plasma. In Exp. 2, bovine plasma was inoculated with porcine respiratory and reproductive syndrome (PRRS) virus propagated previously in MARC cell culture to provide approximately 106.3 TCID50/mL. Three 4-L batches were spray-dried in the same manner as Exp. 1. Before spray-drying, samples contained TCID50 of 104.0, 103.5, and 103'5/mL, respectively. After four consecutive passages in MARC cell cultures, no viable virus was detected in spray-dried bovine plasma. In Exp. 3,36 weaned piglets (28 d of age) were fed a common diet for 14 d and were determined to be negative for PRV, PRRS, and porcine parvovirus titer. Afterwards, pigs were allotted to six pens with six pigs per pen and fed diets containing either 0 or 8% SDAP (as-fed basis) for 63 d. The SDAP used in the feed contained antibody (titer 1:400) against porcine parvovirus. Blood samples were collected from pigs on d 0 and 63 to determine whether feeding SDAP caused seroconversion and development of antibodies against parvovirus, PRRS, or PRV. Inclusion of SDAP in the diet improved growth of pigs without seroconversion. Spray-drying conditions used in this study were effective in eliminating viable pseudorabies and PRRS viruses from bovine plasma. In this study, feeding SDAP that contained functional antibodies did not promote seroconversion in naive animals. [ABSTRACT FROM AUTHOR]

Trauma to the nervous system triggers responses that include oxidative stress due to the generation of reactive oxygen species (ROS). DNA is a major macromolecular target of ROS, and ROS-induced DNA strand breaks activate poly(ADP-ribose)polymerase-1 (PARP-1). Upon activation PARP-1 uses NAD+ as a substrate to catalyze the transfer of ADP-ribose subunits to a host of nuclear proteins. In the face of extensive DNA strand breaks, PARP-1 activation can lead to depletion of intracellular NAD(P)(H) pools, large decreases in ATP, that threaten cell survival. Accordingly, inhibition of PARP-1 activity after acute oxidative injury has been shown to increase cell survival. When NGF-differentiated PC12 cells, an in vitro neuronal model, are exposed to H2O2 there is increased synthesis of poly ADP-ribose and decreases in intracellular NAD(P)(H) and ATP. Addition of the chemical PARP inhibitor 3-aminobenzamide (AB) prior to H2O2 exposure blocks the synthesis of poly ADP-ribose and maintains intracellular NAD(P)(H) and ATP levels. H2O2 injury is characterized by an immediate, necrotic cell death 2h after injury and a delayed apoptotic-like death 12–24h after injury. This apoptotic-like death is characterized by apoptotic membrane changes and apoptotic DNA fragmentation but is not associated with measurable caspase-3 activity. AB delays cell death beyond 24h and increases cell survival by ∼25%. This protective effect is accompanied by significantly decreased necrosis and the apoptotic-like death associated with H2O2 exposure. AB also restores caspase-3 which can be attributed to the activation of the upstream activator of caspase-3, caspase-9. Thus, the maintenance of intracellular ATP levels associated with PARP-1 inhibition shifts cell death from necrosis to apoptosis and from apoptosis to cell survival. Furthermore, the shift from necrosis to apoptosis may be explained, in part, by an energy-dependent activation of caspase-9. [Copyright &y& Elsevier]

Abnormalities of cerebral blood flow during and following hypoxia and ischemia contribute to the progression of tissue injury. Oxidative stress during and following hypoxia is known to markedly increase superoxide anion concentration. There is conflicting evidence that the concentration of superoxide anion regulates cerebral blood flow through its effect on vascular tone, although difficulties in measurement of superoxide anion complicate these studies. In order to test the hypothesis that changes in cerebral blood flow during and following hypoxia are due to changes in extracellular superoxide anion levels, we examined tissue oxygen levels by fiberoptic oximetry and superoxide anion levels using a previously validated cytochrome c coated electrode on the cortical surface and correlated these measurements to cerebral blood flow measured by laser Doppler in rats subjected to 20 min of hypoxia followed by hyperoxic reoxygenation recovery. The results showed a burst of superoxide anion with the onset of reoxygenation that temporally correlated with a transient peak in tissue oxygen tension lasting 10 min. and was eliminated by pretreatment with Cu–Zn superoxide dismutase conjugated to polyethylene glycol. Cerebral blood flow did not differ during hypoxia or recovery in the polyethylene glycol conjugated superoxide dismutase and control treatment groups. This study demonstrated no effect of increased superoxide anion concentration on cerebral blood flow during hyperoxic recovery following hypoxia. [Copyright &y& Elsevier]

Abstract: Objective: To retrospectively evaluate the incidence of cardiovascular events after functioning simultaneous pancreas-kidney transplantation (SPKT). Patients and Methods: Cardiovascular events after 89 SPKT procedures performed at our institution from March 1995 to March 2009 were investigated. Study criteria included normal functioning of both grafts. Patients included 36 women and 53 men, with mean (range) age of 37.7 (25–66) years. Duration of diabetes mellitus was 23.6 (10–48) years, and of dialysis therapy was 19.8 (0–70) months. The exocrine pancreatic secretions were drained to the bladder in 41 patients, and enterically in 45 patients. Mean (SD) follow-up was 58.62 (34.74) months. Results: During follow-up after SPKT, 9 patients (10.1%) experienced cardiovascular events including cerebrovascular accident in 4 patients, myocardial infarction (MI) in 3, and episodes of angina pectoris without evidence of coronary artery disease in 2 patients. Nevertheless, these two patients had sustained an MI that required coronary angioplasty before SPKT. Moreover, coronary angioplasty was required in 2 patients before they were enrolled in the transplantation program because of silent coronary artery disease. Four of 9 cardiovascular events occurred in the perioperative period. No deaths occurred due to cardiovascular events. Patient survival rate was 100%, with both grafts functioning in 87 (97.8%). Conclusion: Cardiovascular events occur relatively frequently in patients undergoing SPKT. In the present study, most events occurred in the perioperative period, but did not result in death. [ABSTRACT FROM AUTHOR]

Abstract: Stress events have been shown to reduce intestinal barrier function (i.e., weaning, co-mingling, pathogen challenge, heat stress, etc.). Normal gut barrier function is important for maintaining nutrient absorption, while reducing exposure of the animal to toxins or pathogens that may be present in the intestinal lumen. Spray-dried plasma (SDP) is a complex mixture of functional components with biological activity independent of their nutritional value. Traditionally, SDP has been used in pig feeds at weaning because its use is associated with an increase in feed intake, growth rate, feed efficiency and reduced scours during the weaning period. In recent studies, the effects of SDP have been demonstrated in pigs at weaning (without pathogenic challenge), in pigs challenged with rotavirus, and in rats injected with a bacterial toxin. In non-challenged pigs, SDP reduced (P <0.05) macrophage numbers in the ileum while in the colon lymphocyte and lamina propria cell density was reduced. The extent and severity of diarrhea was reduced (P <0.05) when feeding SDP to pigs challenged with rotavirus. Spray-dried plasma reduced (P <0.01) dextran flux, increased expression of tight junction proteins and reduced (P <0.05) pro-inflammatory cytokines in the intestinal mucosa in rats injected with a bacterial toxin. Collectively, these findings indicate that SDP reduces intestinal inflammation and improves barrier function. Therefore, addition of SDP to animal feed helps to maintain normal intestinal barrier function and growth performance when the animal is exposed to various degrees of stress events. [ABSTRACT FROM AUTHOR]