285 research outputs found

    Economic feasibility of second generation ethanol with and without indirect greenhouse gas reduction benefits : a simulation for Brazil

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    The aim of this study is to determine the economic feasibility of second generation ethanol from sugar cane, whereby traditional ethanol production is combined with the use of lignocellulosic biomass for ethanol production. By applying cost-benefit analysis, this study evaluated the viability of the second generation ethanol technology as an alternative to conventional sugarcaneto- ethanol, both in terms of processing technology, and of land use impacts. Furthermore, an attempt is made to analyze impacts on CO2 mitigation and land use in economic. The research results indicate that: i) from an economic point of view, the first generation plant is clearly preferable. With IRR of 18.7%, Minimum selling price of US0.31perliter,andNPVofUS 0.31 per liter, and NPV of US 213.0 million, first generation ethanol production from sugar cane has a large economic advantage compared to the second generation plant (IRR of 13.5%, Minimum selling price of US0.40perliterandNPVofUS 0.40 per liter and NPV of US 78.5 million). ii) from an environmental point of view, a second generation biofuel that makes use of lignocellulosic biomass plant is clearly preferable. The second generation plant uses 49.6% less land and avoids a CO2 debt average of 942,282 ton per year throughout the life of the project. iii) Productivity gains improve profitability (IRR) and reduce biofuel prices (Minimum selling prices). Increasing the yearlt Ethanol and sugar cane productivity’s growth rate from 0.5% to 4.0% leads to a range of IRR from 17.5% to 21.5%, and of price from 0.29 US/lto0.32US/l to 0.32 US/l for first generation plant, and from 13.2% to 14.2% and of price from 0.39 US/lto0.40US/l to 0.40 US/l for second generation plant. iv) Process improvement shows little economic impact but matters on environmental side because less land is needed. Up to 10% more land can be saved compared to least advanced technology. v) Energy conversion development can improve income of the plant, especially for the first generation plant. Each 5% improvement can lead to 0.6% change in IRR project, and a reduction of 1.1% in the Minimum selling price. vi) Equipment investment is the most sensitive parameter to alter biofuel prices and profitability. The conventional plant is more sensitive to equipment investment, land prices and trash costs in this order while second generation plant is sensitive to equipment investment and almost insensitive to land prices and trash costs changes. vii) Assuming an average payment of US29.43orhigherpertonCO2debt,thesecondgenerationplantmaybecomeacompetingalternativetoconventional,firstgenerationplant.Onaverage,thetechnologycouldbepaidatreasonablecost(RevenueaverageofUS 29.43 or higher per ton CO2 debt, the second generation plant may become a competing alternative to conventional, first generation plant. On average, the technology could be paid at reasonable cost (Revenue average of US 27.7 million). viii) Productivity gains reduce the repayment time of CO2 debt, with ethanol productivity having a stronger contribution. Besides, from a growth rate of ethanol and sugar cane productivity from 0.5% to 4.0% per year, the repayment time changes from 11.8 years to a range between 6.5 years and 5.5 years and 13 and 9.5, respectively. In conclusion, the appraisal model represents a useful tool for analyzing many issues related with the dilemmas involved in biofuel production

    Review of Small Cell Carcinomas of the Prostate

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    Small cell carcinoma of the prostate is a rare neoplasm, with only a few series hitherto reported. A little less than half of the cases are associated with conventional acinar adenocarcinoma, which are usually high grade. Although consensus has not been reached, the majority of patients with small cell neuroendocrine carcinoma of the prostate have advanced disease at diagnosis and disproportionally low PSA levels compared to patients with conventional acinar adenocarcinoma. Treatment consists mainly of chemotherapy associated with surgery. Radiation therapy is reserved for selected cases. This study reviews the most up-to-date information on small cell carcinomas of the prostate

    Monomorphic post-transplant lymphoproliferative disorder of the tongue: case report and review of literature

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    <p>Abstract</p> <p>Background</p> <p>Post-transplant lymphoproliferative disorder (PTLD) is a spectrum of hematological diseases arising in context of immunosuppression after organ transplantation. PTLD can involve any organ; however, it is extremely rare in oral cavity.</p> <p>Methods</p> <p>Using morphologic and immunophenotypic approaches we have studied a case of monomorphic PTLD of the tongue that developed in a patient following unilateral kidney and pancreas transplantation on immunosuppressive therapy. Additionally, cases of PTLD in the oral cavity were reviewed in the English literature.</p> <p>Results</p> <p>The neoplasm showed large cell morphology and B-cell phenotype. In situ hybridization for Epstein-Barr virus was positive. Complete remission was obtained after decreasing immunosuppressive therapy. The patient remained in remission at 790 days' follow up.</p> <p>Conclusion</p> <p>This rare case increased our awareness of PTLD in the oral cavity of patients following solid organ transplantation and immunosuppressive therapy.</p

    Angiolymphoid hyperplasia with eosinophilia developing in a patient with history of peripheral T-cell lymphoma: evidence for multicentric T-cell lymphoproliferative process

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    <p>Abstract</p> <p>Background</p> <p>Angiolymphoid hyperplasia with eosinophilia (ALHE) is a vasocentric process characterized by infiltrates of lymphocytes and eosinophils, usually affecting the muscular arteries of the head and neck. Currently it is unclear whether it is a reactive or neoplastic process.</p> <p>Report</p> <p>We present a 61-year-old African American male with a twenty year history of superficial skin patches involving the head and neck region. An excisional biopsy of a right submental lymph node revealed an atypical T-cell lymphocytic process, diagnosed as peripheral T-cell lymphoma after immunophenotyping and molecular studies. Three months later the patient underwent a biopsy of a left temporal nodule that was diagnosed as ALHE. Subsequently, at two year follow-up, the patient was diagnosed with Mycosis Fungoides. Polymerase chain reaction for T cell receptor gamma showed the same T-cell receptor gene rearrangement in both the temporal mass and the right submental lymph node.</p> <p>Conclusion</p> <p>ALHE with molecular evidence of monoclonality is extremely unusual, as is the association with nodal peripheral T-cell nodal lymphoma. The findings of this case support our hypothesis that ALHE might be an early form of T-cell lymphoma.</p

    Prostatic carcinomas with neuroendocrine differentiation diagnosed in needle biopsies, a morphologic study of 7 cases among 465 sequential biopsies in a tertiary cancer center

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    Purpose: Neuroendocrine carcinomas (NEC) of the prostate are rare, with only a few series hitherto reported. the objective of this study was to assess in a single institution the clinical and morphologic characteristics of neuroendocrine carcinomas diagnosed in needle core biopsies.Materials and Methods: the current study analyses seven cases diagnosed in needle biopsies at a large tertiary regional cancer center from Northeastern Brazil. Two pathologists reviewed specimens retrospectively, and demographic and morphologic characteristics were compared to 458 acinar tumors diagnosed in the same period.Results: There were five small cell carcinomas and two low-grade neuroendocrine carcinomas (carcinoid). NEC were associated with an acinar component in 5/7 cases and the Gleason score of the acinar component was always > 6. the number of cores involved in prostates with NEC was greater (65% compared to 24% of acinar tumors, p < 0.05). the mean PSA at diagnosis was 417.7 (range 5.7-1593, SD 218.3), compared to 100.5 (p = 0.1) of acinar tumors (range 0.3-8545, SD 22.7). Prostates harboring NEC were bigger (p < 0.001, mean volume 240 mL vs. 53 mL of acinar tumors). Treatment of NEC included palliative surgery, chemotherapy, and hormonal therapy.Conclusions: NEC of the prostate is rare and often associated with a high-grade acinar component. Prostates with NEC tend to be larger and involve a greater number of cores than acinar tumors. PSA at diagnosis does not seem to predict the presence of NE tumors in needle biopsy.Hosp Canc, Inst Canc Ceara, BR-60430230 Fortaleza, Ceara, BrazilEscola Paulista Med, BR-04023 São Paulo, BrazilEscola Paulista Med, BR-04023 São Paulo, BrazilWeb of Scienc

    Fatal parvoviral myocarditis: A case report and review of literature

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    This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens

    Measurement of the neutron capture cross section of the s-only isotope 204Pb from 1 eV to 440 keV

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    The neutron capture cross section of 204Pb has been measured at the CERN n_TOF installation with high resolution in the energy range from 1 eV to 440 keV. An R-matrix analysis of the resolved resonance region, between 1 eV and 100 keV, was carried out using the SAMMY code. In the interval between 100 keV and 440 keV we report the average capture cross section. The background in the entire neutron energy range could be reliably determined from the measurement of a 208Pb sample. Other systematic effects in this measurement could be investigated and precisely corrected by means of detailed Monte Carlo simulations. We obtain a Maxwellian average capture cross section for 204Pb at kT=30 keV of 79(3) mb, in agreement with previous experiments. However our cross section at kT=5 keV is about 35% larger than the values reported so far. The implications of the new cross section for the s-process abundance contributions in the Pb/Bi region are discussed.Comment: 8 pages, 3 figures, article submitted to Phys. Rev.

    Measurement of the (90,91,92,93,94,96)Zr(n,gamma) and (139)La(n,gamma) cross sections at n_TOF

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    Open AccessNeutron capture cross sections of Zr and La isotopes have important implications in the field of nuclear astrophysics as well as in the nuclear technology. In particular the Zr isotopes play a key role for the determination of the neutron density in the He burning zone of the Red Giant star, while the (139)La is important to monitor the s-process abundances from Ba up to Ph. Zr is also largely used as structural materials of traditional and advanced nuclear reactors. The nuclear resonance parameters and the cross section of (90,91,92,93,94,96)Zr and (139)La have been measured at the n_TOF facility at CERN. Based on these data the capture resonance strength and the Maxwellian-averaged cross section were calculated

    New measurement of neutron capture resonances of 209Bi

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    The neutron capture cross section of Bi209 has been measured at the CERN n TOF facility by employing the pulse-height-weighting technique. Improvements over previous measurements are mainly because of an optimized detection system, which led to a practically negligible neutron sensitivity. Additional experimental sources of systematic error, such as the electronic threshold in the detectors, summing of gamma-rays, internal electron conversion, and the isomeric state in bismuth, have been taken into account. Gamma-ray absorption effects inside the sample have been corrected by employing a nonpolynomial weighting function. Because Bi209 is the last stable isotope in the reaction path of the stellar s-process, the Maxwellian averaged capture cross section is important for the recycling of the reaction flow by alpha-decays. In the relevant stellar range of thermal energies between kT=5 and 8 keV our new capture rate is about 16% higher than the presently accepted value used for nucleosynthesis calculations. At this low temperature an important part of the heavy Pb-Bi isotopes are supposed to be synthesized by the s-process in the He shells of low mass, thermally pulsing asymptotic giant branch stars. With the improved set of cross sections we obtain an s-process fraction of 19(3)% of the solar bismuth abundance, resulting in an r-process residual of 81(3)%. The present (n,gamma) cross-section measurement is also of relevance for the design of accelerator driven systems based on a liquid metal Pb/Bi spallation target.Comment: 10 pages, 5figures, recently published in Phys. Rev.
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