Anévrismes complexes de l'aorte abdominale: la chirurgie ouverte est-elle obsolète [The complex aortic abdominal aneurysm: is open surgery old fashion?].

Open surgery is still the main treatment of complex abdominal aortic aneurysm. Nevertheless, this approach is associated with major complications and high mortality rate. Therefore the fenestrated endograft has been used to treat the juxtarenal aneurysms. Unfortunately, no randomised controlled study is available to assess the efficacy of such devices. Moreover, the costs are still prohibitive to generalise this approach. Alternative treatments such as chimney or sandwich technique are being evaluated in order to avoid theses disadvantages. The aim of this paper is to present the endovascular approach to treat juxtarenal aneurysm and to emphasize that this option should be used only by highly specialized vascular centres.

A biophysical model of atrial fibrillation ablation: what can a surgeon learn from a computer model?

AIMS: Surgical ablation procedures for treating atrial fibrillation have been shown to be highly successful. However, the ideal ablation pattern still remains to be determined. This article reports on a systematic study of the effectiveness of the performance of different ablation line patterns. METHODS AND RESULTS: This study of ablation line patterns was performed in a biophysical model of human atria by combining basic lines: (i) in the right atrium: isthmus line, line between vena cavae and appendage line and (ii) in the left atrium: several versions of pulmonary vein isolation, connection of pulmonary veins, isthmus line, and appendage line. Success rates and the presence of residual atrial flutter were documented. Basic patterns yielded conversion rates of only 10-25 and 10-55% in the right and the left atria, respectively. The best result for pulmonary vein isolation was obtained when a single closed line encompassed all veins (55%). Combination of lines in the right/left atrium only led to a success rate of 65/80%. Higher rates, up to 90-100%, could be obtained if right and left lines were combined. The inclusion of a left isthmus line was found to be essential for avoiding uncommon left atrial flutter. CONCLUSION: Some patterns studied achieved a high conversion rate, although using a smaller number of lines than those of the Maze III procedure. The biophysical atrial model is shown to be effective in the search for promising alternative ablation strategies.

Consolidation with Radioimmunotherapy May Prolong Survival in First Remission of Mantle Cell Lymphoma Patients Uneligible for Stem Cell Transplantation, An Analysis of the International RIT-Network

Background: Mantle cell lymphoma (MCL) is a rare subtype (3-9%) of Non Hodgkin Lymphoma (NHL) with a relatively poor prognosis (5-year survival < 40%). Although consolidation of first remission with autologous stem cell transplantation (ASCT) is regarded as "golden standard", less than half of the patients may be subjected to this intensive treatment due to advanced age and co-morbidities. Standard-dose non-myeloablative radioimmunotherapy (RIT) seems to be a very efficient approach for treatment of certain NHL. However, there are almost no data available on the efficacy and safety of RIT in MCL. Methods and Patients: In the RIT-Network, a web-based international registry collecting real observational data from RIT-treated patients, 115 MCL patients treated with ibritumomab tiuxetan were recorded. Most of the patients were elderly males with advanced stage of the disease: median age - 63 (range 31-78); males - 70.4%, stage III/IV - 92%. RIT (i.e. application of ibritumomab tiuxetan) was a part of the first line therapy in 48 pts. (43%). Further 38 pts. (33%) received ibritumomab tiuxetan after two previous chemotherapy regimens, and 33 pts. (24%) after completing 3-8 lines. In 75 cases RIT was applied as a consolidation of chemotherapy induced response; the rest of the patients received ibritumomab tiuxetan because of relapse/refractory disease. At the moment follow up data are available for 74 MCL patients. Results: After RIT the patients achieved high response rate: CR 60.8%, PR 25.7%, and SD 2.7%. Only 10.8% of the patients progressed. For survival analysis many data had to be censored since the documentation had not been completed yet. The projected 3-year overall survival (OAS, fig.1 - image 001.gif) after radioimmunotherapy was 72% for pts. subjected to RIT consolidation versus 29% for those treated in relapse/refractory disease (p=0.03). RIT was feasible for almost all patients; only 3 procedure-related deaths were reported in the whole group. The main adverse event was hematological toxicity (grade III/IV cytopenias) showing a median time of recovery of Hb, WBC and Plt of 45, 40 and 38 days respectively. Conclusion: Standard-dose non-myeloablative RIT is a feasible and safe treatment modality, even for elderly MCL pts. Consolidation radioimmunotherapy with ibritumomab tiuxetan may prolong survival of patients who achieved clinical response after chemotherapy. Therefore, this consolidation approach should be considered as a treatment strategy for those, who are not eligible for ASCT. RIT also has a potential role as a palliation therapy in relapsing/resistant cases.

Multi institutional phase II study of concomitant stereotactic reirradiation and cetuximab for recurrent head and neck cancer.

PURPOSE: Recurrent head and neck cancer is associated to a poor survival prognosis. A high toxicity rate is demonstrated when surgery and/or radiotherapy and/or chemotherapy are combined. Furthermore, the duration of treatment is often not ethically compatible with the expected survival (median survival<1year). Normal tissues tolerance limits the use of reirradiation and stereotactic body radiotherapy (SBRT) could offer precise irradiation while sparing healthy tissues. After completion of a feasibility study, results of a multicentric study (Lille, Nancy & Nice) using SBRT with cetuximab are reported. The aim of the study was to deliver non toxic short course SBRT (2weeks) in order to get the same local control as the one demonstrated with longer protocols. METHODS AND MATERIALS: Patients with inoperable recurrent, or new primary tumor in a previously irradiated area, were included (WHO<3). Reirradiation (RT) dose was 36Gy in six fractions of 6Gy to the 85% isodose line covering 95% of the PTV with 5 injections of concomitant cetuximab (CT). All patients had previous radiotherapy, 85% had previous surgery and 48% previous chemotherapy. RESULTS: Between 11/2007 and 08/2010, 60 were included (46 men and 14 women), 56 received CT+RT, 3 were not treated and 1 received only CT. Median age was 60 (42-87)) and all 56 patients had squamous carcinoma and received concomitant cetuximab. Mean time between previous radiotherapy and the start of SBRT was 38months. Cutaneous toxicity was observed for 41 patients. There was one toxic death from hemorrhage and denutrition. Median follow-up was 11.4months. At 3months, response rate was 58.4% (95% CI: 43.2-72.4%) and disease control rate was 91.7% (95% CI: 80.0-97.7%). The one-year OS rate was 47.5% (95% CI: 30.8-62.4). CONCLUSION: These results suggest that short SBRT with cetuximab is an effective salvage treatment with good response rate in this poor prognosis population with previously irradiated HNC. Treatment is feasible and, with appropriate care to limiting critical structure, acute toxicities are acceptable. This combination may be the reference treatment is this population.

Construction mechanisms and thermal evolution of upper crustal intrusions : the Saint-Jean-du-Doigt bimodal intrusion (Brittany, France)

Understanding the emplacement and growth of intrusive bodies in terms of mechanism, duration, ther¬mal evolution and rates are fundamental aspects of crustal evolution. Recent studies show that many plutons grow in several Ma by in situ accretion of discrete magma pulses, which constitute small-scale magmatic reservoirs. The residence time of magmas, and hence their capacities to interact and differentiate, are con¬trolled by the local thermal environment. The latter is highly dependant on 1) the emplacement depth, 2) the magmas and country rock composition, 3) the country rock thermal conductivity, 4) the rate of magma injection and 5) the geometry of the intrusion. In shallow level plutons, where magmas solidify quickly, evi¬dence for magma mixing and/or differentiation processes is considered by many authors to be inherited from deeper levels. This work shows however that in-situ differentiation and magma interactions occurred within basaltic and felsic sills at shallow depth (0.3 GPa) in the St-Jean-du-Doigt (SJDD) bimodal intrusion, France. This intrusion emplaced ca. 347 Ma ago (IDTIMS U/Pb on zircon) in the Precambrian crust of the Armori- can massif and preserves remarkable sill-like emplacement processes of bimodal mafic-felsic magmas. Field evidence coupled to high precision zircon U-Pb dating document progressive thermal maturation within the incrementally built ioppolith. Early m-thick mafic sills (eastern part) form the roof of the intrusion and are homogeneous and fine-grained with planar contacts with neighboring felsic sills; within a minimal 0.8 Ma time span, the system gets warmer (western part). Sills are emplaced by under-accretion under the old east¬ern part, interact and mingle. A striking feature of this younger, warmer part is in-situ differentiation of the mafic sills in the top 40 cm of the layer, which suggests liquids survival in the shallow crust. Rheological and thermal models were performed in order to determine the parameters required to allow this observed in- situ differentiation-accumulation processes. Strong constraints such as total emplacement durations (ca. 0.8 Ma, TIMS date) and pluton thickness (1.5 Km, gravity model) allow a quantitative estimation of the various parameters required (injection rates, incubation time,...). The results show that in-situ differentiation may be achieved in less than 10 years at such shallow depth, provided that: (1) The differentiating sills are injected beneath consolidated, yet still warm basalt sills, which act as low conductive insulating screens (eastern part formation in the SJDD intrusion). The latter are emplaced in a very short time (800 years) at high injection rate (0.5 m/y) in order to create a "hot zone" in the shallow crust (incubation time). This implies that nearly 1/3 of the pluton (400m) is emplaced by a subsequent and sustained magmatic activity occurring on a short time scale at the very beginning of the system. (2) Once incubation time is achieved, the calculations show that a small hot zone is created at the base of the sill pile, where new injections stay above their solidus T°C and may interact and differentiate. Extraction of differentiated residual liquids might eventually take place and mix with newly injected magma as documented in active syn-emplacement shear-zones within the "warm" part of the pluton. (3) Finally, the model show that in order to maintain a permanent hot zone at shallow level, injection rate must be of 0.03 m/y with injection of 5m thick basaltic sills eveiy 130yr, imply¬ing formation of a 15 km thick pluton. As this thickness is in contradiction with the one calculated for SJDD (1.5 Km) and exceed much the average thickness observed for many shallow level plutons, I infer that there is no permanent hot zone (or magma chambers) at such shallow level. I rather propose formation of small, ephemeral (10-15yr) reservoirs, which represent only small portions of the final size of the pluton. Thermal calculations show that, in the case of SJDD, 5m thick basaltic sills emplaced every 1500 y, allow formation of such ephemeral reservoirs. The latter are formed by several sills, which are in a mushy state and may interact and differentiate during a short time.The mineralogical, chemical and isotopic data presented in this study suggest a signature intermediate be¬tween E-MORB- and arc-like for the SJDD mafic sills and feeder dykes. The mantle source involved produced hydrated magmas and may be astenosphere modified by "arc-type" components, probably related to a sub¬ducting slab. Combined fluid mobile/immobile trace elements and Sr-Nd isotopes suggest that such subduc¬tion components are mainly fluids derived from altered oceanic crust with minor effect from the subducted sediments. Close match between the SJDD compositions and BABB may point to a continental back-arc setting with little crustal contamination. If so, the SjDD intrusion is a major witness of an extensional tectonic regime during the Early-Carboniferous, linked to the subduction of the Rheno-Hercynian Ocean beneath the Variscan terranes. Also of interest is the unusual association of cogenetic (same isotopic compositions) K-feldspar A- type granite and albite-granite. A-type granites may form by magma mixing between the mafic magma and crustal melts. Alternatively, they might derive from the melting of a biotite-bearing quartz-feldspathic crustal protolith triggered by early mafic injections at low crustal levels. Albite-granite may form by plagioclase cu¬mulate remelting issued from A-type magma differentiation.

Holter implantable: reveal [The implantable loop recorder]

The implantable loop recorder developed by Medtronic (Reveal plus) is a small device inserted subcutaneously under local anesthesia in patients with syncope of unexplained origin. This device enables a single lead-ECG recording and has autonomy of two years. Memories are activated during episodes of bradycardia or tachycardia, either automatically or manually. Several studies have shown a high diagnostic rate reaching 50% and demonstrated its cost-effectiveness. There is also a significant reduction in syncopal episodes and a higher quality of life score in patients with syncope of unexplained origin.

Wheat alleles introgress into selfing wild relatives: empirical estimates from approximate Bayesian computation in Aegilops triuncialis.

Extensive gene flow between wheat (Triticum sp.) and several wild relatives of the genus Aegilops has recently been detected despite notoriously high levels of selfing in these species. Here, we assess and model the spread of wheat alleles into natural populations of the barbed goatgrass (Aegilops triuncialis), a wild wheat relative prevailing in the Mediterranean flora. Our sampling, based on an extensive survey of 31 Ae. triuncialis populations collected along a 60 km × 20 km area in southern Spain (Grazalema Mountain chain, Andalousia, totalling 458 specimens), is completed with 33 wheat cultivars representative of the European domesticated pool. All specimens were genotyped with amplified fragment length polymorphism with the aim of estimating wheat admixture levels in Ae. triuncialis populations. This survey first confirmed extensive hybridization and backcrossing of wheat into the wild species. We then used explicit modelling of populations and approximate Bayesian computation to estimate the selfing rate of Ae. triuncialis along with the magnitude, the tempo and the geographical distance over which wheat alleles introgress into Ae. triuncialis populations. These simulations confirmed that extensive introgression of wheat alleles (2.7 × 10(-4) wheat immigrants for each Ae. triuncialis resident, at each generation) into Ae. triuncialis occurs despite a high selfing rate (Fis ≈ 1 and selfing rate = 97%). These results are discussed in the light of risks associated with the release of genetically modified wheat cultivars in Mediterranean agrosystems.

In vitro selection of bacteria with potential for use as probiotics in marine shrimp culture

The objective of this work was to isolate strains of lactic acid bacteria with probiotic potential from the digestive tract of marine shrimp (Litopenaeus vannamei), and to carry out in vitro selection based on multiple characters. The ideotype (ideal proposed strain) was defined by the highest averages for the traits maximum growth velocity, final count of viable cells, and inhibition halo against nine freshwater and marine pathogens, and by the lowest averages for the traits duplication time and resistance of strains to NaCl (1.5 and 3%), pH (6, 8, and 9), and biliary salts (5%). Mahalanobis distance (D²) was estimated among the evaluated strains, and the best ones were those with the shortest distances to the ideotype. Ten bacterial strains were isolated and biochemically identified as Lactobacillus plantarum (3), L. brevis (3), Weissella confusa (2), Lactococcus lactis (1), and L. delbrueckii (1). Lactobacillus plantarum strains showed a wide spectrum of action and the largest inhibition halos against pathogens, both Gram-positive and negative, high growth rate, and tolerance to all evaluated parameters. In relation to ideotype, L. plantarum showed the lowest Mahalanobis (D²) distance, followed by the strains of W. confusa, L. brevis, L. lactis, and L. delbrueckii. Among the analyzed bacterial strains, those of Lactobacillus plantarum have the greatest potential for use as a probiotic for marine shrimp.

From geriatric service to primary care: a retrospective pharmaceutical analysis of the medical prescription

Introduction The population of elderly persons is increasing andnegative outcomes due to polymedication are frequent. Discrepanciesin information about medication are frequent when older persons aretransitioning from hospital to home, increasing the risk of hospitalreadmission. The aims of this study were a) to determine discrepanciesin medical regimen indicated in two official discharge documents(DS = discharge summary, DP=discharge prescription); b) to characterizethe pharmacotherapy prescribed in older patients dischargedfrom a geriatric service.Materials & Methods Elderly patients (N=230) discharged from thegeriatric service (CHUV, Lausanne) over a 6-month period (January toJune 2009) were selected. Community pharmacists compared DS andDP to identify discrepancies including (a) drugs' name; (b) schedule ofadministration, dosage, frequency, prn prescription, treatment durationand galenic formulation. Beers' criteria were applied to identifypotentially inappropriate drugs and a descriptive analysis of drug costs,prescription profiles and generics were also performed.Results On average, patients were 82 ± 7 years old and stayed23.0 ± 11.6 days in the geriatric service. The delay between the datesof patient's discharge with the DP and the sending of the DS to hisgeneral physician averaged 14.0 ± 7.5 days (range 1-55). The DPhad an average of 10.0 ± 3.3 drugs (range 2-19). 77% of patients hadat least one discrepancy. A drug was missing on the DS in 57.8% ofpatients and 19.6% had a missing prn prescription. Among the 2312drugs prescribed, 3% belonged to Beers' list. They were prescribed to61 patients (26.5%), with 6 patients cumulating two Beers' potentiallyinappropriate drugs in their treatment. Analgesics (85% of thepatients), anticoagulants (80%), mineral supplements (77%), laxatives(52%) and antihypertensives (46%) were the drug classes most frequentlyprescribed. Mean costs of treatment as per DP was160.4 ± 179.4 Euros. Generic prescription represented more than 5%of the costs for 3 therapeutic classes (cholesterol-lowering agents(64%), antihypertensives (50%) and antidepressants (47%)).Discussion & Conclusion The high discrepancy rate between medicationlisted in the DP and the DS highlights a need for safetyimprovement. Potential benefits are expected from reinforced pharmacist-physician collaboration in transition from hospital to primarycare. In addition, even though Beers' criteria are questionable, thedrugs prescribed in this already fragile population, and the potentialopportunities of economical optimizations, are advocating thedevelopment and the scientific evaluation of a structured advancedcollaborative pharmacy practice service. This foresees improvedeffectiveness, safety and efficiency in the medication management ofelderly persons.

Effect of spatial processes on the evolution of ecological niches and dispersal in metacommunity systems

RésuméLa coexistence de nombreuses espèces différentes a de tout temps intrigué les biologistes. La diversité et la composition des communautés sont influencées par les perturbations et l'hétérogénéité des conditions environnementales. Bien que dans la nature la distribution spatiale des conditions environnementales soit généralement autocorrélée, cet aspect est rarement pris en compte dans les modèles étudiant la coexistence des espèces. Dans ce travail, nous avons donc abordé, à l'aide de simulations numériques, la coexistence des espèces ainsi que leurs caractéristiques au sein d'un environnement autocorrélé.Afin de prendre en compte cet élément spatial, nous avons développé un modèle de métacommunauté (un ensemble de communautés reliées par la dispersion des espèces) spatialement explicite. Dans ce modèle, les espèces sont en compétition les unes avec les autres pour s'établir dans un nombre de places limité, dans un environnement hétérogène. Les espèces sont caractérisées par six traits: optimum de niche, largeur de niche, capacité de dispersion, compétitivité, investissement dans la reproduction et taux de survie. Nous nous sommes particulièrement intéressés à l'influence de l'autocorrélation spatiale et des perturbations sur la diversité des espèces et sur les traits favorisés dans la métacommunauté. Nous avons montré que l'autocorrélation spatiale peut avoir des effets antagonistes sur la diversité, en fonction du taux de perturbations considéré. L'influence de l'autocorrélation spatiale sur la capacité de dispersion moyenne dans la métacommunauté dépend également des taux de perturbations et survie. Nos résultats ont aussi révélé que de nombreuses espèces avec différents degrés de spécialisation (i.e. différentes largeurs de niche) peuvent coexister. Toutefois, les espèces spécialistes sont favorisées en absence de perturbations et quand la dispersion est illimitée. A l'opposé, un taux élevé de perturbations sélectionne des espèces plus généralistes, associées avec une faible compétitivité.L'autocorrélation spatiale de l'environnement, en interaction avec l'intensité des perturbations, influence donc de manière considérable la coexistence ainsi que les caractéristiques des espèces. Ces caractéristiques sont à leur tour souvent impliquées dans d'importants processus, comme le fonctionnement des écosystèmes, la capacité des espèces à réagir aux invasions, à la fragmentation de l'habitat ou aux changements climatiques. Ce travail a permis une meilleure compréhension des mécanismes responsables de la coexistence et des caractéristiques des espèces, ce qui est crucial afin de prédire le devenir des communautés naturelles dans un environnement changeant.AbstractUnderstanding how so many different species can coexist in nature is a fundamental and long-standing question in ecology. Community diversity and composition are known to be influenced by heterogeneity in environmental conditions and disturbance. Though in nature the spatial distribution of environmental conditions is frequently autocorrelated, this aspect is seldom considered in models investigating species coexistence. In this work, we thus addressed several questions pertaining to species coexistence and composition in spatially autocorrelated environments, with a numerical simulations approach.To take into account this spatial aspect, we developed a spatially explicit model of metacommunity (a set of communities linked by dispersal of species). In this model, species are trophically equivalent, and compete for space in a heterogeneous environment. Species are characterized by six life-history traits: niche optimum, niche breadth, dispersal, competitiveness, reproductive investment and survival rate. We were particularly interested in the influence of environmental spatial autocorrelation and disturbance on species diversity and on the traits of the species favoured in the metacommunity. We showed that spatial autocorrelation can have antagonistic effects on diversity depending on disturbance rate. Similarly, spatial autocorrelation interacted with disturbance rate and survival rate to shape the mean dispersal ability observed in the metacommunity. Our results also revealed that many species with various degrees of specialization (i.e. different niche breadths) can coexist together. However specialist species were favoured in the absence of disturbance, and when dispersal was unlimited. In contrast, high disturbance rate selected for more generalist species, associated with low competitive ability.The spatial structure of the environment, together with disturbance and species traits, thus strongly impacts species diversity and, more importantly, species composition. Species composition is known to affect several important metacommunity properties such as ecosystem functioning, resistance and reaction to invasion, to habitat fragmentation and to climate changes. This work allowed a better understanding of the mechanisms responsible for species composition, which is of crucial importance to predict the fate of natural metacommunities in changing environments

Shallow-transfer rule-based machine translation for Czech to Polish

This article describes the developmentof an Open Source shallow-transfer machine translation system from Czech to Polish in theApertium platform. It gives details ofthe methods and resources used in contructingthe system. Although the resulting system has quite a high error rate, it is still competitive with other systems.

Computer-aided volume measurement of posttraumatic orbits reconstructed with AO titanium mesh plates: accuracy and reliability

PURPOSE: To prospectively evaluate the accuracy and reliability of "freehand" posttraumatic orbital wall reconstruction with AO (Arbeitsgemeinschaft Osteosynthese) titanium mesh plates by using computer-aided volumetric measurement of the bony orbits. METHODS: Bony orbital volume was measured in 12 patients from coronal CT scan slices using OsiriX Medical Image software. After defining the volumetric limits of the orbit, the segmentation of the bony orbital region of interest of each single slice was performed. At the end of the segmentation process, all regions of interest were grouped and the volume was computed. The same procedure was performed on both orbits, and thereafter the volume of the contralateral uninjured orbit was used as a control for comparison. RESULTS: In all patients, the volume data of the reconstructed orbit fitted that of the contralateral uninjured orbit with accuracy to within 1.85 cm3 (7%). CONCLUSIONS: This preliminary study has demonstrated that posttraumatic orbital wall reconstruction using "freehand" bending and placement of AO titanium mesh plates results in a high success rate in re-establishing preoperative bony volume, which closely approximates that of the contralateral uninjured orbit.

Histological description of seminiferous epithelium and cycle length of spermatogenesis in the water shrew Neomys fodiens (Mammalia: Soricidae).

Recently, we examined the spermatogenesis cycle length in two shrews species, Sorex araneus characterized by a very high metabolic rate and a polyandric mating system (sperm competition) resulting in a short cycle and Crocidura russula characterized by a much lower metabolic rate and a monogamous mating system showing a longer cycle. In this study, we investigated the spermatogenesis cycle in Neomys fodiens showing an intermediate metabolic rate. We described the stages of seminiferous epithelium according to the spermatid morphology method and we calculated the cycle length of spermatogenesis using incorporation of 5-bromodeoxyuridine into DNA of the germ cells. Twelve males were injected intraperitoneally with 5-bromodeoxyuridine, and the testes were collected. For cycle length determination, we applied a recently developed statistical method. The calculated cycle length is 8.69 days and the total duration of spermatogenesis based on 4.5 cycles is approximately 39.1 days, intermediate between the duration of spermatogenesis of S. araneus (37.6 days) and C. russula (54.5 days) and therefore congruent with both the metabolic rate hypothesis and the sperm competition hypothesis. Relative testes size of 1.4% of body mass indicates a promiscuous mating system.

Comparative study of the mandarin hybrid fruit characteristics: Nova, Murcott and Ortanique in Capão Bonito SP, Brazil

The Murcott tangor represent 20% of the tangerines trees in São Paulo State being the second more grown. Their fruits have good acceptance in the market cause of the good characteristics presented as: size, attractive internal and external color, transport resistance, high juice rate and industry potential. It is necessary to study the behavior of others varieties, in order to amplify the diversity of tangerine industry, which show suitable characteristics to the fresh fruit market and that make possible different harvest season. Many tangerine varieties, selected from the Citrus Germplasm Bank of the do Centro Avançado de Pesquisa Tecnológica do Agronegócio de Citros "Sylvio Moreira"/IAC, belong to trials carried out in 15 places in São Paulo State. The Capão Bonito area, south-west of the state, is one of this places where the Nova tangelo, the Ortanique and the Murcott tangors are showing quite good results about their fruit qualities. This paper had as an objective to compare the fruit characteristics of the Nova tangelo, the Murcott and the Ortanique tangors grafted on two rootstocks: Rangpur lime and Cleopatra mandarin. Accordingly to the gotten results, is possible to conclude that Nova and Ortanique had shown weight, width, fruit shape and juice percent, similar to the Murcott. In compliance with the harvest season, the Nova present suitable conditions to fresh fruit market in May and June. By the other hand the Murcott fruits can be harvested in July to August and the Ortanique in August to September. For this reason, is possible extend the harvest season of this mandarin-like, from two to five month, occurring inclusive in a period out of the crop at the north hemisphere.

Formation and Control of Trace Metal Emissions in Co-Firing of Biomass, Peat, and Wastes in Fluidised Bed Combustors

Environmentally harmful consequences of fossil fuel utilisation andthe landfilling of wastes have increased the interest among the energy producers to consider the use of alternative fuels like wood fuels and Refuse-Derived Fuels, RDFs. The fluidised bed technology that allows the flexible use of a variety of different fuels is commonly used at small- and medium-sized power plants ofmunicipalities and industry in Finland. Since there is only one mass-burn plantcurrently in operation in the country and no intention to build new ones, the co-firing of pre-processed wastes in fluidised bed boilers has become the most generally applied waste-to-energy concept in Finland. The recently validated EU Directive on Incineration of Wastes aims to mitigate environmentally harmful pollutants of waste incineration and co-incineration of wastes with conventional fuels. Apart from gaseous flue gas pollutants and dust, the emissions of toxic tracemetals are limited. The implementation of the Directive's restrictions in the Finnish legislation is assumed to limit the co-firing of waste fuels, due to the insufficient reduction of the regulated air pollutants in the existing flue gas cleaning devices. Trace metals emission formation and reduction in the ESP, the condensing wet scrubber, the fabric filter, and the humidification reactor were studied, experimentally, in full- and pilot-scale combustors utilising the bubbling fluidised bed technology, and, theoretically, by means of reactor model calculations. The core of the model is a thermodynamic equilibrium analysis. The experiments were carried out with wood chips, sawdust, and peat, and their refuse-derived fuel, RDF, blends. In all, ten different fuels or fuel blends were tested. Relatively high concentrations of trace metals in RDFs compared to the concentrations of these metals in wood fuels increased the trace metal concentrations in the flue gas after the boiler ten- to hundred-folds, when RDF was co-fired with sawdust in a full-scale BFB boiler. In the case of peat, lesser increase in trace metal concentrations was observed, due to the higher initial trace metal concentrations of peat compared to sawdust. Despite the high removal rate of most of the trace metals in the ESP, the Directive emission limits for trace metals were exceeded in each of the RDF co-firing tests. The dominat trace metals in fluegas after the ESP were Cu, Pb and Mn. In the condensing wet scrubber, the flue gas trace metal emissions were reduced below the Directive emission limits, whenRDF pellet was used as a co-firing fuel together with sawdust and peat. High chlorine content of the RDFs enhanced the mercuric chloride formation and hence the mercury removal in the ESP and scrubber. Mercury emissions were lower than theDirective emission limit for total Hg, 0.05 mg/Nm3, in all full-scale co-firingtests already in the flue gas after the ESP. The pilot-scale experiments with aBFB combustor equipped with a fabric filter revealed that the fabric filter alone is able to reduce the trace metal concentrations, including mercury, in the flue gas during the RDF co-firing approximately to the same level as they are during the wood chip firing. Lower trace metal emissions than the Directive limits were easily reached even with a 40% thermal share of RDF co-firing with sawdust.Enrichment of trace metals in the submicron fly ash particle fraction because of RDF co-firing was not observed in the test runs where sawdust was used as the main fuel. The combustion of RDF pellets with peat caused an enrichment of As, Cd, Co, Pb, Sb, and V in the submicron particle mode. Accumulation and release oftrace metals in the bed material was examined by means of a bed material analysis, mass balance calculations and a reactor model. Lead, zinc and copper were found to have a tendency to be accumulated in the bed material but also to have a tendency to be released from the bed material into the combustion gases, if the combustion conditions were changed. The concentration of the trace metal in the combustion gases of the bubbling fluidised bed boiler was found to be a summary of trace metal fluxes from three main sources. They were (1) the trace metal flux from the burning fuel particle (2) the trace metal flux from the ash in the bed, and (3) the trace metal flux from the active alkali metal layer on the sand (and ash) particles in the bed. The amount of chlorine in the system, the combustion temperature, the fuel ash composition and the saturation state of the bed material in regard to trace metals were discovered to be key factors affecting therelease process. During the co-firing of waste fuels with variable amounts of e.g. ash and chlorine, it is extremely important to consider the possible ongoingaccumulation and/or release of the trace metals in the bed, when determining the flue gas trace metal emissions. If the state of the combustion process in regard to trace metals accumulation and/or release in the bed material is not known,it may happen that emissions from the bed material rather than the combustion of the fuel in question are measured and reported.