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Abstract: Selected native shrub species from central Portugal and NW Spain, Cytisus multiflorus (broom), Erica arborea (heath), Pterospartum tridentatum (carqueisa) and Ulex europaeus (gorse) were characterized for physical, thermal and chemical properties for combustion. The studied shrub species showed ash contents in the range 1–2%, nitrogen contents above 0.6%, and sulfur contents below 0.1% at both areas of study. A significant effect of species on Higher Heating Value (HHV) was observed, with no significant effect of the location of study, central Portugal or NW Spain. The higher HHV (24.4MJkg−1) was recorded for heath, this species also shows the higher average carbon and lower nitrogen content values of the studied species. Analysis of the chemical composition of the ashes revealed alkali metals contents of 24–30%, representing a potential sintering, fouling and bed agglomeration risk in the combustion of the studied species. Ash As, Cd, Pb, Co, Cu, Mn, Ni, Cr, and Zn content was below national and most of European legislation maximum levels for these elements for ash application as fertilizer, with the exception of some of the more conservative limits for Cd, Cu, Cr, and Zn from Northern and central European countries legislation. [Copyright &y& Elsevier]

Spatially crown biomass of Pinus pinaster stands and shrubland above-ground biomass (AGB) estimation was carried-out in a region located in Centre-North Portugal, by means of different approaches including forest inventory data, remotely sensed imagery and spatial prediction models. Two cover types (pine stands and shrubland) were inventoried and biomass assessed in a total of 276 sample field plots. We compared AGB spatial predictions derived from Direct Radiometric Relationships (DRR) of remotely sensed data; and the geostatistical method Regression-kriging (RK), using remotely sensed data as auxiliary variables. Also, Ordinary Kriging (OK), Universal Kriging (UK), Inverse Distance Weighted (IDW) and Thiessen Polygons estimations were performed and tested. The comparison of AGB maps shows distinct predictions among DRR and RK; and Kriging and deterministic methods, indicating the inadequacy from these later ones to map AGB over large areas. DRR and RK methods produced lower statistical error values, in pine stands and shrubland, when compared to kriging and deterministic interpolators. Since forest landscape is not continuous variable, the tested forest variables showed low spatial autocorrelation, which makes kriging methods unsuitable to these purposes. Despite the geostatistical method RK did not increase the accuracy of estimates developed by DRR, denser sampling schemes and different auxiliary variables should be explored, in order to test if the accuracy of predictions is improved. [Copyright &y& Elsevier]

Abstract: Following the European Union strategy concerning renewable energy (RE), Portugal established in their national policy programmes that the production of electrical energy from RE should reach 45% of the total supply by 2010. Since Portugal has large forest biomass resources, a significant part of this energy will be obtained from this source. In addition to the two existing electric power plants, with 22MW of power capacity, 13 new power plants having a total of 86.4MW capacity are in construction. Together these could generate a combination of electrical and thermal energy, known as combined heat and power (CHP) production. As these power plants will significantly increase the exploitation of forests resources, this article evaluates the potential quantities of available forest biomass residue for that purpose. In addition to examining the feasibility of producing both types of energy, we also examine the potential for producing only electric energy. Results show that if only electricity is generated some regions will need to have alternative fuel sources to fulfil the demand. However, if cogeneration is implemented the wood fuel resource will be sufficient to fulfill the required capacity demand. [Copyright &y& Elsevier]

Abstract: Background: The major causes of renal transplant loss are death and chronic allograft dysfunction (CAD). The aims of this study were to determine the incidence of CAD in our population and the relation between allograft survival and immunosuppressive regimens. Methods: We studied retrospectively 473 patients who received deceased donor kidney transplants with at least 1 allograft biopsy between January 1990 and May 2007. Clinical data included age, gender, biopsy data, and immunosuppression before and after kidney biopsy. Mean age was 45.4 ± 12.7 years including 65% males with a mean follow-up of 6.7 ± 4.5 years. CAD was observed in 177 of 473 biopsies: 48 patients showed interstitial fibrosis (IF); 101 chronic rejection (CR); 16 transplant glomerulopathy (TG); and 12, CR and TG. Mean follow-up since the discovery of the histologic feature was 60.5 ± 50.5 months for IF; 38.3 ± 40.8 for CR, and 18.2 ± 19.2 for TG. Results: CAD, which was more common in younger patients (P = .03), correlated upon univariate and multivariate analysis with CKD stage 5d development (P < .001). Deposition of C4d in peritubular capillaries was more frequent among CAD patients (P = .004), an association with particular relevance to recipients with CR (P = .02) and TG (P < .001). When we analyzed CAD subpopulation, we observed a positive correlation between allograft survival and immunosuppression modification after biopsy. Substitution of sirolimus (40/177) was shown in univariate, multivariate and Cox regression analyses to be a renal protector (P < .002). Allograft survival was also correlated with initial mycophenolate mofetil versus azathioprine, (62/177) immunosuppression (P < .001). Conclusion: CAD, a frequent histologic feature, may benefit from sirolimus conversion. [Copyright &y& Elsevier]

Abstract: Background: Prospective testing for posttransplant circulating anti-HLA antibodies seems to be a critical noninvasive tool, but confirmatory data are lacking. Materials and Methods: Over the last 3 years, peritubular capillary (PTC) C4d deposition was prospectively sought by an immunofluorescence technique applied to frozen tissue in biopsies obtained for allograft dysfunction. Screening for circulating anti-HLA class I/II alloantibodies (AlloAb) by the flow cytometric test was performed simultaneously. Results: We evaluated 132 sets of biopsies and simultaneous serum samples. PTC C4d deposition was demonstrated in 15.9% (21/132) of biopsies. Circulating anti-HLA I/II AlloAb were detected in 25% (33/132) of serum samples. Employing receiver-operator characteristic (ROC) curves for all C4d-positive biopsies, screening for AlloAb showed a global specificity of 82% and sensitivity of 61.9%. When this analysis was restricted to biopsies obtained in the first month posttransplantation, the sensitivity increased to 81.8%, but the specificity decreased to 76.9%. After the first month posttransplantation, we observed sensitivity of 40.0% and a specificity of 86.4%. In the first month posttransplantation, all patients with a diagnosis of acute antibody-mediated rejection displayed circulating anti-HLA class I/II, but not always at the same time as the C4d-positive biopsy. Conclusions: In the first month posttransplantation, prospective monitoring of anti-HLA antibodies may be useful. The high sensitivity allows the identification of patients at risk, affording an earlier diagnosis of antibody-mediated rejection. After the first month, the test can be used to evaluate allograft dysfunction episodes, since positivity is highly suggestive of an antibody-mediated process. [Copyright &y& Elsevier]