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Amazon river dolphins Inia geoffrensis are on the path to extinction in the heart of their range
- A. R. Martin, V. M. F. da Silva
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Riverine cetaceans are threatened globally by increasing anthropogenic impacts, and the Yangtze river dolphin Lipotes vexillifer is already extinct. The Amazon river dolphin Inia geoffrensis is widely distributed, but is categorized as Endangered on the IUCN Red List. Drowning in gillnets and being hunted for fish bait are probably the main causes of its decline. A long-term (25-year) study of the biology and ecology of I. geoffrensis in and near the Mamirauá Reserve in Amazonas state, Brazil, has produced estimates of survival and reproductive rates based on the individual recognition of > 650 animals. Concurrently, monthly standardized counts of dolphins along a fixed transect in the Reserve over 22 years demonstrated a sustained, profound decline. In this study we tested whether the measured rate of population decline is consistent with population parameters estimated from independent data, using population viability analysis. With the known parameters as input, programme Vortex predicted population extinction in all scenarios and a 95% loss of dolphins within 50 years. With default parameters, the model predicted a 5.5% annual decline, which is consistent with that observed. We conclude that the Amazon river dolphin population is in severe decline because of human pressures, even in one of the better protected parts of its range. Unless the accidental and deliberate killing of this species is rapidly reduced, it is highly likely that the Amazon river dolphin will follow its Yangtze counterpart to extinction.
Performance, carcass traits and meat quality of lambs fed with different roughage: concentrate ratios associated with variable physically effective neutral detergent fibre content
- L. de O. Queiroz, A. M. Barbosa, G. B. Mourão, M. A. Fonseca, L. F. B. Pinto, J. M. da Silva Júnior, T. M. Silva, A. G. V. O. Lima, L. R. Bezerra, R. L. Oliveira
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- The Journal of Agricultural Science / Volume 159 / Issue 3-4 / April 2021
- Published online by Cambridge University Press:
- 21 June 2021, pp. 293-303
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This study evaluated the effect of roughage:concentrate (R:C) ratio associated with a variable particle size of physically effective neutral detergent fibre (peNDF8) in the forage (Tifton-85 hay) on the performance, carcass traits and meat quality of lambs. Seventy-two 4-month-old, non-castrated Santa Ines male lambs (23.5 ± 2.32 kg BW) were distributed in a completely randomized design, in a 2 × 2 factorial arrangement [two peNDF8 hay particle sizes (13 and 6 mm) and two R:C ratios (700:300 and 500:500 g/kg DM total)]. DMI, DM, NFC and TDN digestibility's, N-intake and N-faecal excretion were affected by the R:C ratio (P < 0.05). However, the N-retained was not affected by the studied variables (P > 0.05). It was observed an interaction (P < 0.05) between the peNDF8 and R:C ratios for final BW, average daily gain (ADG), colour parameters and pH 24 h. The lower roughage ratio provided greater (P < 0.05) concentrations of C14:1, C16:1–cis9, C18:1–cis9, ΣMUFA, Σn–6:Σn–3 and hypocholesterolemic/hypercholesterolemic index, enzymatic activity Δ9desaturase-C16 and -C18. Lambs fed a lower roughage diet had improved performance and feed efficiency, however, presented reduced polyunsaturated fatty acids (PUFA) concentrations in the meat, especially Σn–3 family. Higher roughage diet and larger peNDF8 particle size improved the concentrations of PUFA while decreased Σn–6:Σn–3 ratio in meat. Larger peNDF8 particle size associated with higher roughage proportion, have reduced animal performance however, it increased protein concentration, a* and C* colour parameter without affecting fatty acids profile of Longissimus lumborum muscle.
A comparison of two rotational stocking strategies on the foraging behaviour and herbage intake by grazing sheep
- J. V. Savian, R. M. T. Schons, J. C. Mezzalira, A. Barth Neto, G. F. Da Silva Neto, M. A. Benvenutti, P. C. de F. Carvalho
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An understanding of the processes involved in grazing behaviour is a prerequisite for the design of efficient grassland management systems. The purpose of managing the grazing process is to identify sward structures that can maximize animal forage daily intake and optimize grazing time. Our aim was to evaluate the effect of different grazing management strategies on foraging behaviour and herbage intake by sheep grazing Italian ryegrass under rotational stocking. The experiment was carried out in 2015 in southern Brazil. The experimental design was a randomized complete block with two grazing management strategies and four replicates. The grazing management treatments were a traditional rotational stocking (RT), with pre- and post-grazing sward heights of 25 and 5 cm, respectively, and a ‘Rotatinuous’ stocking (RN) with pre- and post-grazing sward heights of 18 and 11 cm, respectively. Male sheep with an average live weight of 32 ± 2.3 kg were used. As intended, the pre- and post-grazing sward heights were according to the treatments. The pre-grazing leaf/stem ratio of the Italian ryegrass pasture did not differ between treatments (P > 0.05) (~2.87), but the post-grazing leaf/stem ratio was greater (P < 0.001) in the RN than in the RT treatment (1.59 and 0.76, respectively). The percentage of the non-grazed area was greater (P < 0.01) in post-grazing for RN compared with RT treatment, with an average of 29.7% and 3.49%, respectively. Herbage nutritive value was greater for the RN than for the RT treatment, with greater CP and lower ADF and NDF contents. The total time spent grazing, ruminating and resting did not differ between treatments (P > 0.05), with averages of 439, 167 and 85 min, respectively. The bite rate, feeding stations per min and steps per min by sheep were greater (P < 0.05) in the RN than in the RT treatment. The grazing time per hour and the bite rate were greater (P < 0.05) in the afternoon than in the morning in both treatments. The daily herbage intake by sheep grazing Italian ryegrass was greater (P < 0.05) in the RN than in the RT treatment (843.7 and 707.8 g organic matter/sheep, respectively). Our study supports the idea that even though the grazing time was not affected by the grazing management strategies when the animal behaviour responses drive management targets, such as in ‘Rotatinuous’ stocking, the sheep herbage intake is maximized, and the grazing time is optimized.
Everolimus for cardiac rhabdomyomas in children with tuberous sclerosis. The ORACLE study protocol (everOlimus for caRdiac rhAbdomyomas in tuberous sCLErosis): a randomised, multicentre, placebo-controlled, double-blind phase II trial
- Erica V. Stelmaszewski, Daniella B. Parente, Alberto Farina, Anna Stein, Anthony Gutierrez, Antonio F. Raquelo-Menegassio, Carla Manterola, Carolina F. de Sousa, Carolina Victor, Dina Maki, Elias M. Morón, Fabiano F. de Abrantes, Fatima Iqbal, Jazmin Camacho-Vilchez, Joanna Jimenez-Pavón, Juan P. Polania, Lorenzo Thompson, Lygia Bonanato, Matthias Diebold, Maria V. C. P. Da Silva, Mariam W. J. Nashwan, Marianna A. G. Galvani, Osama E. A. Idris, Pierina Danos, Rocio Ortiz-Lopez, Rofida A. A. Mahmoud, Sergio Gresse, Jr, Karla L. Loss
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- Cardiology in the Young / Volume 30 / Issue 3 / March 2020
- Published online by Cambridge University Press:
- 27 January 2020, pp. 337-345
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Introduction:
Tuberous sclerosis complex is a rare genetic disorder leading to the growth of hamartomas in multiple organs, including cardiac rhabdomyomas. Children with symptomatic cardiac rhabdomyoma require frequent admissions to intensive care units, have major complications, namely, arrhythmias, cardiac outflow tract obstruction and heart failure, affecting the quality of life and taking on high healthcare cost. Currently, there is no standard pharmacological treatment for this condition, and the management includes a conservative approach and supportive care. Everolimus has shown positive effects on subependymal giant cell astrocytomas, renal angiomyolipoma and refractory seizures associated with tuberous sclerosis complex. However, evidence supporting efficacy in symptomatic cardiac rhabdomyoma is limited to case reports. The ORACLE trial is the first randomised clinical trial assessing the efficacy of everolimus as a specific therapy for symptomatic cardiac rhabdomyoma.
Methods:ORACLE is a phase II, prospective, randomised, placebo-controlled, double-blind, multicentre protocol trial. A total of 40 children with symptomatic cardiac rhabdomyoma secondary to tuberous sclerosis complex will be randomised to receive oral everolimus or placebo for 3 months. The primary outcome is 50% or more reduction in the tumour size related to baseline. As secondary outcomes we include the presence of arrhythmias, pericardial effusion, intracardiac obstruction, adverse events, progression of tumour reduction and effect on heart failure.
Conclusions:ORACLE protocol addresses a relevant unmet need in children with tuberous sclerosis complex and cardiac rhabdomyoma. The results of the trial will potentially support the first evidence-based therapy for this condition.
Delivering 21st century Antarctic and Southern Ocean science
- M.C. Kennicutt II, Y.D. Kim, M. Rogan-Finnemore, S. Anandakrishnan, S.L. Chown, S. Colwell, D. Cowan, C. Escutia, Y. Frenot, J. Hall, D. Liggett, A.J. Mcdonald, U. Nixdorf, M.J. Siegert, J. Storey, A. Wåhlin, A. Weatherwax, G.S. Wilson, T. Wilson, R. Wooding, S. Ackley, N. Biebow, D. Blankenship, S. Bo, J. Baeseman, C.A. Cárdenas, J. Cassano, C. Danhong, J. Dañobeitia, J. Francis, J. Guldahl, G. Hashida, L. Jiménez Corbalán, A. Klepikov, J. Lee, M. Leppe, F. Lijun, J. López-Martinez, M. Memolli, Y. Motoyoshi, R. Mousalle Bueno, J. Negrete, M.A. Ojeda Cárdenes, M. Proaño Silva, S. Ramos-Garcia, H. Sala, H. Shin, X. Shijie, K. Shiraishi, T. Stockings, S. Trotter, D.G. Vaughan, J. Viera Da Unha De Menezes, V. Vlasich, Q. Weijia, J.-G. Winther, H. Miller, S. Rintoul, H. Yang
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- Antarctic Science / Volume 28 / Issue 6 / December 2016
- Published online by Cambridge University Press:
- 21 October 2016, pp. 407-423
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The Antarctic Roadmap Challenges (ARC) project identified critical requirements to deliver high priority Antarctic research in the 21st century. The ARC project addressed the challenges of enabling technologies, facilitating access, providing logistics and infrastructure, and capitalizing on international co-operation. Technological requirements include: i) innovative automated in situ observing systems, sensors and interoperable platforms (including power demands), ii) realistic and holistic numerical models, iii) enhanced remote sensing and sensors, iv) expanded sample collection and retrieval technologies, and v) greater cyber-infrastructure to process ‘big data’ collection, transmission and analyses while promoting data accessibility. These technologies must be widely available, performance and reliability must be improved and technologies used elsewhere must be applied to the Antarctic. Considerable Antarctic research is field-based, making access to vital geographical targets essential. Future research will require continent- and ocean-wide environmentally responsible access to coastal and interior Antarctica and the Southern Ocean. Year-round access is indispensable. The cost of future Antarctic science is great but there are opportunities for all to participate commensurate with national resources, expertise and interests. The scope of future Antarctic research will necessitate enhanced and inventive interdisciplinary and international collaborations. The full promise of Antarctic science will only be realized if nations act together.
F-16 Performance of a Room Temperature Gas Proportional Scintillation Counter in X-ray Analysis of Metallic Alloys Excited with Alpha Particles
- F. I. G. M. Borges, S. J. C. do Carmo, T. H. V. T. Dias, F. P. Santos, F. P. S. C. Gil, A. M. F. Trindade, R. M. Curado da Silva, C. A. N. Conde
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- Powder Diffraction / Volume 22 / Issue 2 / June 2007
- Published online by Cambridge University Press:
- 20 May 2016, p. 178
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2013 multistate outbreaks of Cyclospora cayetanensis infections associated with fresh produce: focus on the Texas investigations
- F. ABANYIE, R. R. HARVEY, J. R. HARRIS, R. E. WIEGAND, L. GAUL, M. DESVIGNES-KENDRICK, K. IRVIN, I. WILLIAMS, R. L. HALL, B. HERWALDT, E. B. GRAY, Y. QVARNSTROM, M. E. WISE, V. CANTU, P. T. CANTEY, S. BOSCH, A. J. DA SILVA, A. FIELDS, H. BISHOP, A. WELLMAN, J. BEAL, N. WILSON, A. E. FIORE, R. TAUXE, S. LANCE, L. SLUTSKER, M. PARISE, the Multistate Cyclosporiasis Outbreak Investigation Team
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- Journal:
- Epidemiology & Infection / Volume 143 / Issue 16 / December 2015
- Published online by Cambridge University Press:
- 13 April 2015, pp. 3451-3458
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The 2013 multistate outbreaks contributed to the largest annual number of reported US cases of cyclosporiasis since 1997. In this paper we focus on investigations in Texas. We defined an outbreak-associated case as laboratory-confirmed cyclosporiasis in a person with illness onset between 1 June and 31 August 2013, with no history of international travel in the previous 14 days. Epidemiological, environmental, and traceback investigations were conducted. Of the 631 cases reported in the multistate outbreaks, Texas reported the greatest number of cases, 270 (43%). More than 70 clusters were identified in Texas, four of which were further investigated. One restaurant-associated cluster of 25 case-patients was selected for a case-control study. Consumption of cilantro was most strongly associated with illness on meal date-matched analysis (matched odds ratio 19·8, 95% confidence interval 4·0–∞). All case-patients in the other three clusters investigated also ate cilantro. Traceback investigations converged on three suppliers in Puebla, Mexico. Cilantro was the vehicle of infection in the four clusters investigated; the temporal association of these clusters with the large overall increase in cyclosporiasis cases in Texas suggests cilantro was the vehicle of infection for many other cases. However, the paucity of epidemiological and traceback information does not allow for a conclusive determination; moreover, molecular epidemiological tools for cyclosporiasis that could provide more definitive linkage between case clusters are needed.
Persistence and remission of ADHD during adulthood: a 7-year clinical follow-up study
- R. G. Karam, V. Breda, F. A. Picon, D. L. Rovaris, M. M. Victor, C. A. I. Salgado, E. S. Vitola, K. L. Silva, P. O. Guimarães-da-Silva, N. R. Mota, A. Caye, P. Belmonte-de-Abreu, L. A. Rohde, E. H. Grevet, C. H. D. Bau
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- Psychological Medicine / Volume 45 / Issue 10 / July 2015
- Published online by Cambridge University Press:
- 23 January 2015, pp. 2045-2056
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Background
Course and predictors of persistence of attention deficit hyperactivity disorder (ADHD) in adults are still largely unknown. Neurobiological and clinical differences between child and adult ADHD raise the need for follow-up studies of patients diagnosed during adulthood. This study investigates predictors of ADHD persistence and the possibility of full remission 7 years after baseline assessment.
MethodA 7-year follow-up study of adults with ADHD (n = 344, mean age 34.1 years, 49.9% males) was conducted. Variables from different domains (social demographics, co-morbidities, temperament, medication status, ADHD measures) were explored with the aim of finding potential predictors of ADHD persistence.
ResultsRetention rate was 66% (n = 227). Approximately a third of the sample (n = 70, 30.2%) did not maintain ADHD criteria and 28 (12.4%) presented full remission (<4 symptoms), independently of changes in co-morbidity or cognitive demand profiles. Baseline predictors of diagnostic persistence were higher number of inattention symptoms [odds ratio (OR) 8.05, 95% confidence interval (CI) 2.54–25.45, p < 0.001], number of hyperactivity/impulsivity symptoms (OR 1.18, 95% CI 1.04–1.34, p = 0.01), oppositional defiant disorder (OR 3.12, 95% CI 1.20–8.11, p = 0.02), and social phobia (OR 3.59, 95% CI 1.12–11.47, p = 0.03).
ConclusionsDespite the stage of brain maturation in adults suggests stability, approximately one third of the sample did not keep full DSM-IV diagnosis at follow-up, regardless if at early, middle or older adulthood. Although full remission is less common than in childhood, it should be considered as a possible outcome among adults.
Euclid space mission: a cosmological challenge for the next 15 years
- R. Scaramella, Y. Mellier, J. Amiaux, C. Burigana, C.S. Carvalho, J.C. Cuillandre, A. da Silva, J. Dinis, A. Derosa, E. Maiorano, P. Franzetti, B. Garilli, M. Maris, M. Meneghetti, I. Tereno, S. Wachter, L. Amendola, M. Cropper, V. Cardone, R. Massey, S. Niemi, H. Hoekstra, T. Kitching, L. Miller, T. Schrabback, E. Semboloni, A. Taylor, M. Viola, T. Maciaszek, A. Ealet, L. Guzzo, K. Jahnke, W. Percival, F. Pasian, M. Sauvage, the Euclid Collaboration
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- Journal:
- Proceedings of the International Astronomical Union / Volume 10 / Issue S306 / May 2014
- Published online by Cambridge University Press:
- 01 July 2015, pp. 375-378
- Print publication:
- May 2014
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Euclid is the next ESA mission devoted to cosmology. It aims at observing most of the extragalactic sky, studying both gravitational lensing and clustering over ~15,000 square degrees. The mission is expected to be launched in year 2020 and to last six years. The sheer amount of data of different kinds, the variety of (un)known systematic effects and the complexity of measures require efforts both in sophisticated simulations and techniques of data analysis. We review the mission main characteristics, some aspects of the the survey and highlight some of the areas of interest to this meeting.
Grazing behaviour, herbage intake and animal performance of beef cattle heifers on marandu palisade grass subjected to intensities of continuous stocking management
- S. C. DA SILVA, F. M. A. GIMENES, D. O. L. SARMENTO, A. F. SBRISSIA, D. E. OLIVEIRA, A. HERNADEZ-GARAY, A. V. PIRES
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- Journal:
- The Journal of Agricultural Science / Volume 151 / Issue 5 / October 2013
- Published online by Cambridge University Press:
- 15 November 2012, pp. 727-739
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The ability to adapt to a range of edaphic conditions favours the widespread use of marandu palisade grass in high as well as low input systems of animal production in Brazil. However, little information exists regarding the influence of grazing management practices on sward structure and the carry-over effects on animal responses. The present experiment was planned to evaluate animal behaviour, herbage intake (HI) and nutritive value, herbage accumulation and body weight gain (BWG) of beef cattle heifers grazing marandu palisade grass subjected to intensities of continuous stocking management. Treatments corresponded to four sward surface heights (SSH: 100, 200, 300 and 400 mm) and were allocated to experimental units (1200 m2 paddocks) according to a randomized complete block design with four replications. Herbage accumulation rate (HAR) varied with season of the year and SSH, with highest and lowest values recorded during summer and winter, respectively. During the summer, herbage accumulation was larger on swards managed at 200, 300 and 400 mm, with the opposite occurring during winter/early spring. Stocking rate (SR) and number of grazing days (GD) followed a similar seasonal pattern of variation, with values decreasing as SSH increased. Crude protein (CP) and in vitro organic matter digestibility (IVOMD) of hand-plucked herbage decreased as SSH increased from 100 to 400 mm, while the inverse happened with BWG (from 0·190 to 0·930 kg/day, respectively). Bite mass (BM) increased and rate of biting and grazing time (GT) decreased as SSH increased, with daily HI being larger on tall (300 and 400 mm) relative to short (100 and 200 mm) swards. Grazing management affected the nutritive value and the amount of herbage consumed, particularly through changes in BM. However, variations in intake were relatively more important than variations in nutritive value in influencing animal performance, highlighting the importance of providing favourable harvest conditions for grazing animals by establishing adequate sward targets for management.
A novel triazolic naphthofuranquinone induces autophagy in reservosomes and impairment of mitosis in Trypanosoma cruzi
- M. C. FERNANDES, E. N. DA SILVA, JR., A. V. PINTO, S. L. DE CASTRO, R. F. S. MENNA-BARRETO
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- Parasitology / Volume 139 / Issue 1 / January 2012
- Published online by Cambridge University Press:
- 23 September 2011, pp. 26-36
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Chagas' disease, caused by the protozoan Trypanosoma cruzi, represents a serious health problem in Latin America, and the available chemotherapy, which is based on 2 nitro-derivatives, is not satisfactory. In folk medicine, natural products including naphthoquinones have been employed for the treatment of different parasitic diseases. In the pursuit of alternative drugs for Chagas' disease, we investigated the mechanism of action of the triazolic naphthoquinone (TN; 2,2-dimethyl-3-(4-phenyl-1H-1,2,3-triazol-1-yl)-2,3-dihydronaphtho[1,2-b]furan-4,5-dione), which is the most active compound against T. cruzi trypomastigotes among a series of naphthofuranquinones. TN was active against the 3 parasite forms producing a dose-dependent inhibitory effect. In epimastigotes, TN induced reservosome disruption, flagellar blebbing, Golgi disorganization, the presence of cytosolic concentric membrane structures and abnormal multiflagellar parasites. The treatment also led to the appearance of well-developed endoplasmic reticulum profiles surrounding organelles that associated with an increase in monodansylcadaverine labelling, suggesting autophagy as part of the TN mechanism of action. Interestingly, no ultrastructural damage was detected in the mitochondria of naphthoquinone-treated epimastigotes. Flow cytometric analysis demonstrated an impairment of mitosis, an increase in ROS production and the maintenance of mitochondrial membrane potential. TN could be a good starting point in the investigation of a chemotherapeutic approach for the treatment of Chagas' disease.
Contributors
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- By Rose Teteki Abbey, K. C. Abraham, David Tuesday Adamo, LeRoy H. Aden, Efrain Agosto, Victor Aguilan, Gillian T. W. Ahlgren, Charanjit Kaur AjitSingh, Dorothy B E A Akoto, Giuseppe Alberigo, Daniel E. Albrecht, Ruth Albrecht, Daniel O. Aleshire, Urs Altermatt, Anand Amaladass, Michael Amaladoss, James N. Amanze, Lesley G. Anderson, Thomas C. Anderson, Victor Anderson, Hope S. Antone, María Pilar Aquino, Paula Arai, Victorio Araya Guillén, S. Wesley Ariarajah, Ellen T. Armour, Brett Gregory Armstrong, Atsuhiro Asano, Naim Stifan Ateek, Mahmoud Ayoub, John Alembillah Azumah, Mercedes L. García Bachmann, Irena Backus, J. Wayne Baker, Mieke Bal, Lewis V. Baldwin, William Barbieri, António Barbosa da Silva, David Basinger, Bolaji Olukemi Bateye, Oswald Bayer, Daniel H. Bays, Rosalie Beck, Nancy Elizabeth Bedford, Guy-Thomas Bedouelle, Chorbishop Seely Beggiani, Wolfgang Behringer, Christopher M. Bellitto, Byard Bennett, Harold V. Bennett, Teresa Berger, Miguel A. Bernad, Henley Bernard, Alan E. Bernstein, Jon L. Berquist, Johannes Beutler, Ana María Bidegain, Matthew P. Binkewicz, Jennifer Bird, Joseph Blenkinsopp, Dmytro Bondarenko, Paulo Bonfatti, Riet en Pim Bons-Storm, Jessica A. Boon, Marcus J. Borg, Mark Bosco, Peter C. Bouteneff, François Bovon, William D. Bowman, Paul S. Boyer, David Brakke, Richard E. Brantley, Marcus Braybrooke, Ian Breward, Ênio José da Costa Brito, Jewel Spears Brooker, Johannes Brosseder, Nicholas Canfield Read Brown, Robert F. Brown, Pamela K. Brubaker, Walter Brueggemann, Bishop Colin O. Buchanan, Stanley M. Burgess, Amy Nelson Burnett, J. Patout Burns, David B. Burrell, David Buttrick, James P. Byrd, Lavinia Byrne, Gerado Caetano, Marcos Caldas, Alkiviadis Calivas, William J. Callahan, Salvatore Calomino, Euan K. Cameron, William S. Campbell, Marcelo Ayres Camurça, Daniel F. Caner, Paul E. Capetz, Carlos F. Cardoza-Orlandi, Patrick W. Carey, Barbara Carvill, Hal Cauthron, Subhadra Mitra Channa, Mark D. Chapman, James H. Charlesworth, Kenneth R. Chase, Chen Zemin, Luciano Chianeque, Philip Chia Phin Yin, Francisca H. Chimhanda, Daniel Chiquete, John T. Chirban, Soobin Choi, Robert Choquette, Mita Choudhury, Gerald Christianson, John Chryssavgis, Sejong Chun, Esther Chung-Kim, Charles M. A. Clark, Elizabeth A. Clark, Sathianathan Clarke, Fred Cloud, John B. Cobb, W. Owen Cole, John A Coleman, John J. Collins, Sylvia Collins-Mayo, Paul K. Conkin, Beth A. Conklin, Sean Connolly, Demetrios J. Constantelos, Michael A. Conway, Paula M. Cooey, Austin Cooper, Michael L. Cooper-White, Pamela Cooper-White, L. William Countryman, Sérgio Coutinho, Pamela Couture, Shannon Craigo-Snell, James L. Crenshaw, David Crowner, Humberto Horacio Cucchetti, Lawrence S. Cunningham, Elizabeth Mason Currier, Emmanuel Cutrone, Mary L. Daniel, David D. Daniels, Robert Darden, Rolf Darge, Isaiah Dau, Jeffry C. Davis, Jane Dawson, Valentin Dedji, John W. de Gruchy, Paul DeHart, Wendy J. Deichmann Edwards, Miguel A. De La Torre, George E. Demacopoulos, Thomas de Mayo, Leah DeVun, Beatriz de Vasconcellos Dias, Dennis C. Dickerson, John M. Dillon, Luis Miguel Donatello, Igor Dorfmann-Lazarev, Susanna Drake, Jonathan A. Draper, N. Dreher Martin, Otto Dreydoppel, Angelyn Dries, A. J. Droge, Francis X. D'Sa, Marilyn Dunn, Nicole Wilkinson Duran, Rifaat Ebied, Mark J. Edwards, William H. Edwards, Leonard H. Ehrlich, Nancy L. Eiesland, Martin Elbel, J. Harold Ellens, Stephen Ellingson, Marvin M. Ellison, Robert Ellsberg, Jean Bethke Elshtain, Eldon Jay Epp, Peter C. Erb, Tassilo Erhardt, Maria Erling, Noel Leo Erskine, Gillian R. Evans, Virginia Fabella, Michael A. Fahey, Edward Farley, Margaret A. Farley, Wendy Farley, Robert Fastiggi, Seena Fazel, Duncan S. Ferguson, Helwar Figueroa, Paul Corby Finney, Kyriaki Karidoyanes FitzGerald, Thomas E. FitzGerald, John R. Fitzmier, Marie Therese Flanagan, Sabina Flanagan, Claude Flipo, Ronald B. Flowers, Carole Fontaine, David Ford, Mary Ford, Stephanie A. Ford, Jim Forest, William Franke, Robert M. Franklin, Ruth Franzén, Edward H. Friedman, Samuel Frouisou, Lorelei F. Fuchs, Jojo M. Fung, Inger Furseth, Richard R. Gaillardetz, Brandon Gallaher, China Galland, Mark Galli, Ismael García, Tharscisse Gatwa, Jean-Marie Gaudeul, Luis María Gavilanes del Castillo, Pavel L. Gavrilyuk, Volney P. Gay, Metropolitan Athanasios Geevargis, Kondothra M. George, Mary Gerhart, Simon Gikandi, Maurice Gilbert, Michael J. Gillgannon, Verónica Giménez Beliveau, Terryl Givens, Beth Glazier-McDonald, Philip Gleason, Menghun Goh, Brian Golding, Bishop Hilario M. Gomez, Michelle A. Gonzalez, Donald K. Gorrell, Roy Gottfried, Tamara Grdzelidze, Joel B. Green, Niels Henrik Gregersen, Cristina Grenholm, Herbert Griffiths, Eric W. Gritsch, Erich S. Gruen, Christoffer H. Grundmann, Paul H. Gundani, Jon P. Gunnemann, Petre Guran, Vidar L. Haanes, Jeremiah M. Hackett, Getatchew Haile, Douglas John Hall, Nicholas Hammond, Daphne Hampson, Jehu J. Hanciles, Barry Hankins, Jennifer Haraguchi, Stanley S. Harakas, Anthony John Harding, Conrad L. Harkins, J. William Harmless, Marjory Harper, Amir Harrak, Joel F. Harrington, Mark W. Harris, Susan Ashbrook Harvey, Van A. Harvey, R. Chris Hassel, Jione Havea, Daniel Hawk, Diana L. Hayes, Leslie Hayes, Priscilla Hayner, S. Mark Heim, Simo Heininen, Richard P. Heitzenrater, Eila Helander, David Hempton, Scott H. Hendrix, Jan-Olav Henriksen, Gina Hens-Piazza, Carter Heyward, Nicholas J. Higham, David Hilliard, Norman A. Hjelm, Peter C. Hodgson, Arthur Holder, M. Jan Holton, Dwight N. Hopkins, Ronnie Po-chia Hsia, Po-Ho Huang, James Hudnut-Beumler, Jennifer S. Hughes, Leonard M. Hummel, Mary E. Hunt, Laennec Hurbon, Mark Hutchinson, Susan E. Hylen, Mary Beth Ingham, H. Larry Ingle, Dale T. Irvin, Jon Isaak, Paul John Isaak, Ada María Isasi-Díaz, Hans Raun Iversen, Margaret C. Jacob, Arthur James, Maria Jansdotter-Samuelsson, David Jasper, Werner G. Jeanrond, Renée Jeffery, David Lyle Jeffrey, Theodore W. Jennings, David H. Jensen, Robin Margaret Jensen, David Jobling, Dale A. Johnson, Elizabeth A. Johnson, Maxwell E. Johnson, Sarah Johnson, Mark D. Johnston, F. Stanley Jones, James William Jones, John R. Jones, Alissa Jones Nelson, Inge Jonsson, Jan Joosten, Elizabeth Judd, Mulambya Peggy Kabonde, Robert Kaggwa, Sylvester Kahakwa, Isaac Kalimi, Ogbu U. Kalu, Eunice Kamaara, Wayne C. Kannaday, Musimbi Kanyoro, Veli-Matti Kärkkäinen, Frank Kaufmann, Léon Nguapitshi Kayongo, Richard Kearney, Alice A. Keefe, Ralph Keen, Catherine Keller, Anthony J. Kelly, Karen Kennelly, Kathi Lynn Kern, Fergus Kerr, Edward Kessler, George Kilcourse, Heup Young Kim, Kim Sung-Hae, Kim Yong-Bock, Kim Yung Suk, Richard King, Thomas M. King, Robert M. Kingdon, Ross Kinsler, Hans G. Kippenberg, Cheryl A. Kirk-Duggan, Clifton Kirkpatrick, Leonid Kishkovsky, Nadieszda Kizenko, Jeffrey Klaiber, Hans-Josef Klauck, Sidney Knight, Samuel Kobia, Robert Kolb, Karla Ann Koll, Heikki Kotila, Donald Kraybill, Philip D. W. Krey, Yves Krumenacker, Jeffrey Kah-Jin Kuan, Simanga R. Kumalo, Peter Kuzmic, Simon Shui-Man Kwan, Kwok Pui-lan, André LaCocque, Stephen E. Lahey, John Tsz Pang Lai, Emiel Lamberts, Armando Lampe, Craig Lampe, Beverly J. Lanzetta, Eve LaPlante, Lizette Larson-Miller, Ariel Bybee Laughton, Leonard Lawlor, Bentley Layton, Robin A. Leaver, Karen Lebacqz, Archie Chi Chung Lee, Marilyn J. Legge, Hervé LeGrand, D. L. LeMahieu, Raymond Lemieux, Bill J. Leonard, Ellen M. Leonard, Outi Leppä, Jean Lesaulnier, Nantawan Boonprasat Lewis, Henrietta Leyser, Alexei Lidov, Bernard Lightman, Paul Chang-Ha Lim, Carter Lindberg, Mark R. Lindsay, James R. Linville, James C. Livingston, Ann Loades, David Loades, Jean-Claude Loba-Mkole, Lo Lung Kwong, Wati Longchar, Eleazar López, David W. Lotz, Andrew Louth, Robin W. Lovin, William Luis, Frank D. Macchia, Diarmaid N. J. MacCulloch, Kirk R. MacGregor, Marjory A. MacLean, Donald MacLeod, Tomas S. Maddela, Inge Mager, Laurenti Magesa, David G. Maillu, Fortunato Mallimaci, Philip Mamalakis, Kä Mana, Ukachukwu Chris Manus, Herbert Robinson Marbury, Reuel Norman Marigza, Jacqueline Mariña, Antti Marjanen, Luiz C. L. Marques, Madipoane Masenya (ngwan'a Mphahlele), Caleb J. D. Maskell, Steve Mason, Thomas Massaro, Fernando Matamoros Ponce, András Máté-Tóth, Odair Pedroso Mateus, Dinis Matsolo, Fumitaka Matsuoka, John D'Arcy May, Yelena Mazour-Matusevich, Theodore Mbazumutima, John S. McClure, Christian McConnell, Lee Martin McDonald, Gary B. McGee, Thomas McGowan, Alister E. McGrath, Richard J. McGregor, John A. McGuckin, Maud Burnett McInerney, Elsie Anne McKee, Mary B. McKinley, James F. McMillan, Ernan McMullin, Kathleen E. McVey, M. Douglas Meeks, Monica Jyotsna Melanchthon, Ilie Melniciuc-Puica, Everett Mendoza, Raymond A. Mentzer, William W. Menzies, Ina Merdjanova, Franziska Metzger, Constant J. Mews, Marvin Meyer, Carol Meyers, Vasile Mihoc, Gunner Bjerg Mikkelsen, Maria Inêz de Castro Millen, Clyde Lee Miller, Bonnie J. Miller-McLemore, Alexander Mirkovic, Paul Misner, Nozomu Miyahira, R. W. L. Moberly, Gerald Moede, Aloo Osotsi Mojola, Sunanda Mongia, Rebeca Montemayor, James Moore, Roger E. Moore, Craig E. Morrison O.Carm, Jeffry H. Morrison, Keith Morrison, Wilson J. Moses, Tefetso Henry Mothibe, Mokgethi Motlhabi, Fulata Moyo, Henry Mugabe, Jesse Ndwiga Kanyua Mugambi, Peggy Mulambya-Kabonde, Robert Bruce Mullin, Pamela Mullins Reaves, Saskia Murk Jansen, Heleen L. Murre-Van den Berg, Augustine Musopole, Isaac M. T. Mwase, Philomena Mwaura, Cecilia Nahnfeldt, Anne Nasimiyu Wasike, Carmiña Navia Velasco, Thulani Ndlazi, Alexander Negrov, James B. Nelson, David G. Newcombe, Carol Newsom, Helen J. 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Phan, Isabel Apawo Phiri, William S. F. Pickering, Derrick G. Pitard, William Elvis Plata, Zlatko Plese, John Plummer, James Newton Poling, Ronald Popivchak, Andrew Porter, Ute Possekel, James M. Powell, Enos Das Pradhan, Devadasan Premnath, Jaime Adrían Prieto Valladares, Anne Primavesi, Randall Prior, María Alicia Puente Lutteroth, Eduardo Guzmão Quadros, Albert Rabil, Laurent William Ramambason, Apolonio M. Ranche, Vololona Randriamanantena Andriamitandrina, Lawrence R. Rast, Paul L. Redditt, Adele Reinhartz, Rolf Rendtorff, Pål Repstad, James N. Rhodes, John K. Riches, Joerg Rieger, Sharon H. Ringe, Sandra Rios, Tyler Roberts, David M. Robinson, James M. Robinson, Joanne Maguire Robinson, Richard A. H. Robinson, Roy R. Robson, Jack B. Rogers, Maria Roginska, Sidney Rooy, Rev. Garnett Roper, Maria José Fontelas Rosado-Nunes, Andrew C. Ross, Stefan Rossbach, François Rossier, John D. Roth, John K. Roth, Phillip Rothwell, Richard E. Rubenstein, Rosemary Radford Ruether, Markku Ruotsila, John E. Rybolt, Risto Saarinen, John Saillant, Juan Sanchez, Wagner Lopes Sanchez, Hugo N. Santos, Gerhard Sauter, Gloria L. Schaab, Sandra M. Schneiders, Quentin J. Schultze, Fernando F. Segovia, Turid Karlsen Seim, Carsten Selch Jensen, Alan P. F. Sell, Frank C. Senn, Kent Davis Sensenig, Damían Setton, Bal Krishna Sharma, Carolyn J. Sharp, Thomas Sheehan, N. Gerald Shenk, Christian Sheppard, Charles Sherlock, Tabona Shoko, Walter B. Shurden, Marguerite Shuster, B. Mark Sietsema, Batara Sihombing, Neil Silberman, Clodomiro Siller, Samuel Silva-Gotay, Heikki Silvet, John K. Simmons, Hagith Sivan, James C. Skedros, Abraham Smith, Ashley A. Smith, Ted A. Smith, Daud Soesilo, Pia Søltoft, Choan-Seng (C. S.) Song, Kathryn Spink, Bryan Spinks, Eric O. Springsted, Nicolas Standaert, Brian Stanley, Glen H. Stassen, Karel Steenbrink, Stephen J. Stein, Andrea Sterk, Gregory E. Sterling, Columba Stewart, Jacques Stewart, Robert B. Stewart, Cynthia Stokes Brown, Ken Stone, Anne Stott, Elizabeth Stuart, Monya Stubbs, Marjorie Hewitt Suchocki, David Kwang-sun Suh, Scott W. Sunquist, Keith Suter, Douglas Sweeney, Charles H. Talbert, Shawqi N. Talia, Elsa Tamez, Joseph B. Tamney, Jonathan Y. Tan, Yak-Hwee Tan, Kathryn Tanner, Feiya Tao, Elizabeth S. Tapia, Aquiline Tarimo, Claire Taylor, Mark Lewis Taylor, Bishop Abba Samuel Wolde Tekestebirhan, Eugene TeSelle, M. Thomas Thangaraj, David R. Thomas, Andrew Thornley, Scott Thumma, Marcelo Timotheo da Costa, George E. “Tink” Tinker, Ola Tjørhom, Karen Jo Torjesen, Iain R. Torrance, Fernando Torres-Londoño, Archbishop Demetrios [Trakatellis], Marit Trelstad, Christine Trevett, Phyllis Trible, Johannes Tromp, Paul Turner, Robert G. Tuttle, Archbishop Desmond Tutu, Peter Tyler, Anders Tyrberg, Justin Ukpong, Javier Ulloa, Camillus Umoh, Kristi Upson-Saia, Martina Urban, Monica Uribe, Elochukwu Eugene Uzukwu, Richard Vaggione, Gabriel Vahanian, Paul Valliere, T. J. 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Yee, Viktor Yelensky, Yeo Khiok-Khng, Gustav K. K. Yeung, Angela Yiu, Amos Yong, Yong Ting Jin, You Bin, Youhanna Nessim Youssef, Eliana Yunes, Robert Michael Zaller, Valarie H. Ziegler, Barbara Brown Zikmund, Joyce Ann Zimmerman, Aurora Zlotnik, Zhuo Xinping
- Edited by Daniel Patte, Vanderbilt University, Tennessee
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- The Cambridge Dictionary of Christianity
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- 05 August 2012
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- 20 September 2010, pp xi-xliv
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A new genotype of Trypanosoma cruzi associated with bats evidenced by phylogenetic analyses using SSU rDNA, cytochrome b and Histone H2B genes and genotyping based on ITS1 rDNA
- A. MARCILI, L. LIMA, M. CAVAZZANA, JR., A. C. V. JUNQUEIRA, H. H. VELUDO, F. MAIA DA SILVA, M. CAMPANER, F. PAIVA, V. L. B. NUNES, M. M. G. TEIXEIRA
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- Parasitology / Volume 136 / Issue 6 / May 2009
- Published online by Cambridge University Press:
- 16 April 2009, pp. 641-655
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We characterized 15 Trypanosoma cruzi isolates from bats captured in the Amazon, Central and Southeast Brazilian regions. Phylogenetic relationships among T. cruzi lineages using SSU rDNA, cytochrome b, and Histone H2B genes positioned all Amazonian isolates into T. cruzi I (TCI). However, bat isolates from the other regions, which had been genotyped as T. cruzi II (TC II) by the traditional genotyping method based on mini-exon gene employed in this study, were not nested within any of the previously defined TCII sublineages, constituting a new genotype designated as TCbat. Phylogenetic analyses demonstrated that TCbat indeed belongs to T. cruzi and not to other closely related bat trypanosomes of the subgenus Schizotrypanum, and that although separated by large genetic distances TCbat is closest to lineage TCI. A genotyping method targeting ITS1 rDNA distinguished TCbat from established T. cruzi lineages, and from other Schizotrypanum species. In experimentally infected mice, TCbat lacked virulence and yielded low parasitaemias. Isolates of TCbat presented distinctive morphological features and behaviour in triatomines. To date, TCbat genotype was found only in bats from anthropic environments of Central and Southeast Brazil. Our findings indicate that the complexity of T. cruzi is larger than currently known, and confirmed bats as important reservoirs and potential source of T. cruzi infections to humans.
Phylogeny, taxonomy and grouping of Trypanosoma rangeli isolates from man, triatomines and sylvatic mammals from widespread geographical origin based on SSU and ITS ribosomal sequences
- F. MAIA DA SILVA, H. NOYES, M. CAMPANER, A. C. V. JUNQUEIRA, J. R. COURA, N. AÑEZ, J. J. SHAW, J. R. STEVENS, M. M. G. TEIXEIRA
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- Parasitology / Volume 129 / Issue 5 / November 2004
- Published online by Cambridge University Press:
- 05 October 2004, pp. 549-561
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Phylogenetic relationships among Trypanosoma rangeli isolates from man, wild mammals and triatomine bugs from widespread geographical origin were inferred by comparison of the small subunit of ribosomal gene sequences. The phylogenetic trees indicated that the subgenus Herpetosoma is polyphyletic and strongly supported division of this group into two monophyletic lineages, one made up of T. rangeli, T. rangeli-like and allied species and other consisting of T. lewisi and related taxa. Based on phylogenetic analysis, morphology, behaviour in vertebrate and invertebrate hosts and epidemiology we propose: a) the validation of Herpetosoma as a taxon comprised only for species of group lewisi and the maintenance of T. lewisi as the type-species of this subgenus; b) the classification of T. rangeli, T. rangeli-like and allied species into a ‘T. rangeli-clade’ more closely related to Schizotrypanum than to T. lewisi or T. brucei. The phylogenetic tree disclosed at least 4 groups within the clade T. rangeli, all confirmed by polymorphism of the internal transcribed spacer, thus conferring for the first time phylogenetic support to groups of T. rangeli and corroborating the high complexity of this taxon. Grouping was independent of their mammalian host-species and geographical origin, indicating that other factors are determining this segregation.
River dolphins and flooded forest: seasonal habitat use and sexual segregation of botos (Inia geoffrensis) in an extreme cetacean environment
- A. R. Martin, V. M. F. da Silva
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- Journal:
- Journal of Zoology / Volume 263 / Issue 3 / July 2004
- Published online by Cambridge University Press:
- 18 June 2004, pp. 295-305
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- July 2004
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Habitat use by the boto, or Amazon river dolphin Inia geoffrensis, was investigated in and around the Mamirauá Reserve, Brazil. Largely forested with numerous channels and lakes, Mamirauá comprises a variety of seasonal floodplain habitats known collectively as várzea. The annual cycle of flooding in this region (amplitude 11–15 m) dominates all life. Profound seasonal differences in dolphin density between habitats were consistent with known fish movements, in turn dictated by changes in water level and dissolved oxygen. An exodus of botos from floodplain to river at low water prevents dolphins being trapped in areas that become entirely dry. Densities of botos in floodplain channels were seasonally higher (up to 18 km−2) than reported for any cetacean worldwide. Adults were largely segregated by sex except at low water. Females and calves dominated in chavascal habitat–the areas most remote from rivers, which were preferred by males. Probable causes of this segregation are the energetic requirements of calves and the safety of females and/or calves from male harassment. Some 80% of botos occurring on rivers were within 150 m of the margins. The reliance of adult females and calves on várzea in a region with exceptional dolphin densities demonstrates the importance of floodplain habitats for the boto, and may be the key determinant of this species‘ distribution.
Randomly amplified polymorphic DNA analysis of Trypanosoma rangeli and allied species from human, monkeys and other sylvatic mammals of the Brazilian Amazon disclosed a new group and a species-specific marker
- F. MAIA DA SILVA, A. C. RODRIGUES, M. CAMPANER, C. S. A. TAKATA, M. C. BRIGIDO, A. C. V. JUNQUEIRA, J. R. COURA, G. F. TAKEDA, J. J. SHAW, M. M. G. TEIXEIRA
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- Journal:
- Parasitology / Volume 128 / Issue 3 / March 2004
- Published online by Cambridge University Press:
- 03 March 2004, pp. 283-294
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We characterized 14 trypanosome isolates from sylvatic mammals (9 from primates, 1 from sloth, 2 from anteaters and 2 from opossum) plus 2 human isolates of Brazilian Amazon. These isolates were proven to be Trypanosoma rangeli by detection of metacyclic trypomastigotes in the salivary glands of triatomines and by a specific PCR assay. Polymorphism determined by randomly amplified polymorphic DNA (RAPD) revealed that most (12) of the Brazilian T. rangeli isolates from the Amazon differed from those of other geographical regions, thus constituting a new group of T. rangeli. Four Brazilian isolates clustered together with a previously described group (A) that was described as being composed of being isolates from Colombia and Venezuela. Isolates from Panama and El Salvador form another group. The isolate from Southern Brazil did not cluster to any of the above-mentioned groups. This is the first study that assesses the genetic relationship of a large number of isolates from wild mammals, especially from non-human primates. A randomly-amplified DNA fragment (Tra625) exclusive to T. rangeli was used to develop a PCR assay able to detect all T. rangeli groups.
Optical And Structural properties of Vertical Aligned Self-Assembled InAs Quantum Dots Multilayers
- J. C. González, M. I. N. da Silva, W. N. Rodrigues, F. M. Matinaga, R. Magalhaes-Paniago, M. V. Moreira, A. G. de Oliveira, D. Ugarte
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- Journal:
- MRS Online Proceedings Library Archive / Volume 676 / 2001
- Published online by Cambridge University Press:
- 21 March 2011, Y8.24
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- 2001
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In this work, we report optical and structural properties of vertical aligned self-assembled InAs quantum dots multilayers. The InAs quantum dots samples were grown by Molecular Beam Epitaxy. Employing Atomic Force Microscopy, Transmission Electron Microscopy, and Gracing Incident X-ray Diffraction we have studied the structural properties of samples with different number of periods of the multiplayer structure, as well as different InAs coverage. The optical properties were studied using Photoluminescence spectroscopy.
Photoconductive Bi12MO20-type films prepared by pulsed laser deposition
- J. E. Alfonso, M. J. Martín, V. Volkov, C. Zaldo, M. Aguiló, M. F. da Silva, J. C. Soares
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- Journal:
- Journal of Materials Research / Volume 14 / Issue 11 / November 1999
- Published online by Cambridge University Press:
- 31 January 2011, pp. 4409-4417
- Print publication:
- November 1999
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Bi12TiO20 (BTO); Bi12GaxBi1−xO19.5 (BGaO); and Bi12(M1/3P2/3)O20, M = Cd, Zn, and Ni (BMPO) thin films were prepared by pulsed laser deposition using a KrF excimer laser on (100)Y-stabilized zirconia (YSZ), (100)Bi12GeO20 (BGO), and (110)Bi12SiO20 (BSO) crystalline substrates. All these films have a sillenite structure. On (100)YSZ the sillenite is oriented as {310} with the 〈130〉 direction parallel to the 〈021〉YSZ directions (〈130〉{310}BTO〈021〉{100}YSZ). On (100)BGO and (110)BSO the sillenite film reproduces the substrate orientation, and the films formed are able to channel He+ particles. The optimum deposition temperatures for BTO and BGaO are 600 and 550 °C, respectively. Higher temperatures must be avoided to minimize the nucleation of Bi-deficient phases due to the diffusion of Bi into the YSZ substrates. BMPO films are polycrystalline. The lattice parameters of these films were determined. The crystalline films support guided optical modes. The refractive indices obtained for the films are close to those measured in bulk crystals, being slightly larger for films deposited on isomorphous sillenite substrates. The crystalline films deposited on YSZ are photoconductors when excited in the green and blue spectral regions.
Optoelectronic Properties of High-Gap Amorphous Silicon-Carbon Alloys
- V. Chu, J. P. Conde, P. Brogueira, P. Micaelo, J. P. Jarego, M. F. da Silva, J. C. Soares
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- MRS Online Proceedings Library Archive / Volume 377 / 1995
- Published online by Cambridge University Press:
- 15 February 2011, 565
- Print publication:
- 1995
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The dependence of the properties of hydrogenated amorphous silicon-carbon alloys deposited with a 1:10 silane (SiH4) to methane (CH4) or ethylene (C2H4) gas flow ratios with the hydrogen dilution, deposition pressure and power is studied. In methane-based films the carbon content shows a decrease (from ≈0.75 to 0.55) with increasing hydrogen dilution from 0 to 98%, while the ethylene-based films show no dependence of the carbon fraction (≈0.9) on hydrogen dilution. The photoconductivity shows an increase for hydrogen dilutions above 90= for both methane and ethylene-based films. While this increase is attributed, in the case of methane, to the observed decrease in carbon content, no corresponding decrease in carbon content is observed in the ethylene-based films, suggesting a decrease in the density of recombination centers with hydrogen dilution. The Urbach tail and the room-temperature photoluminescence peak correlate with carbon content independent of the carbon source-gas and deposition conditions used.