4,603 results on '"André V"'
Search Results
2. B-meson production at forward rapidities in pp collisions at the LHC: estimating the intrinsic bottom contribution
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Yuri N. Lima, André V. Giannini, and Victor P. Gonçalves
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Astrophysics ,QB460-466 ,Nuclear and particle physics. Atomic energy. Radioactivity ,QC770-798 - Abstract
Abstract The production of B mesons at forward rapidities is strongly sensitive to the behavior of the gluon and bottom distribution functions for small and large values of the Bjorken-x variable. In this exploratory study, we estimate the cross-section for the $$B^{\pm }$$ B ± meson production in the kinematic range probed by the LHCb detector and that will be analyzed by the future Forward Physics Facility (FPF) considering the hybrid formalism, the solution of the running coupling Balitsky–Kovchegov equation and distinct descriptions for the bottom distribution function. We assume an ansatz for the intrinsic bottom component in the proton wave function, and estimate its impact on the transverse momentum, rapidity and Feynman-x distributions. Our results indicate that the presence of an intrinsic bottom strongly modifies the magnitude of the cross-section at ultra-forward rapidities ( $$y \ge 6$$ y ≥ 6 ), which implies an enhancement of the $$B^{\pm }$$ B ± production at the FPF. Possible implications on the prompt neutrino flux at ultra-high energies are also briefly discussed.
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- 2024
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3. Treatment of schizencephaly: A brief review and case study
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Moussa Diallo, Youssouf Traoré, André V. Tokpa, Youssouf Sogoba, Izoudine B. Koumaré, and Drissa Kanikomo
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Orthopedic surgery ,RD701-811 ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Introduction: Schizencephaly is a rare disease. It is a poorly understood pathology. The clinical signs are variable and the diagnosis is made by elimination. The treatment is varied with poor results. Corticosteroids are not commonly used medications. Case Presentation: The observation concerns a 5-month-old child, born with a motor deficit in the right hemibody. His parents had an unremarkable medical history. After brain imaging for epileptic seizures, the child is referred for neurosurgery 5 months later. The diagnosis of schizencephaly was mentioned. Antiepileptic treatment associated with corticosteroid therapy for two weeks was started. Motor physiotherapy began at the same time. At 6 months after start of treatment, the evolution was satisfactory marked by a clear improvement in the motor deficit and a complete cessation of seizures. Conclusions: Due to its rarity, the diagnosis of schizencephaly is made by elimination. Brain MRI is the best radiological examination. Corticosteroid therapy combined with physiotherapy can have an impact on good progress. Treatment should be early.
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- 2024
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4. Genetic and biological insights into Hydatigera taeniaeformis in invasive black rats from southern Chile
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Cristian A. Alvarez Rojas, Cristian Bonacic, Rodrigo Salgado, Lucia Peters, Diego Fredes, André V. Rubio, Sebastián Muñoz-Leal, Pablo Oyarzún-Ruiz, and A. Alonso Aguirre
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Chile ,cox1 gene ,genetic variability ,Hydatigera taeniaeformis ,Rattus rattus ,Veterinary medicine ,SF600-1100 - Abstract
IntroductionThis study investigates the genetic variability of Hydatigera taeniaeformis in black rats (Rattus rattus), a common tapeworm that infects cats and rodents worldwide. Despite its widespread presence and zoonotic potential, little is known about the genetic diversity of this parasite in the Americas.MethodsWe conducted DNA barcoding analysis using mitochondrial cox1 gene sequences using samples collected from 171 invasive wild black rats, captured in the temperate rainforest of Southern Chile. We also included two adult parasites isolated from road killed Kodkods (Leopardus guigna), a small felid species native to the Americas.ResultsOur findings revealed only two haplotypes, suggesting low genetic variability in a parasite that arrived in the Americas with the Spanish colonization.DiscussionThese haplotypes are more closely related to parasite populations from Peru, Africa, Australia, and Europe, suggesting an origin linked to the Spanish colonization, possibly from North Africa via the Canary Islands. The study also analyzed infection rates, parasite size, and their correlation with host body size, age, and weight, revealing significant patterns. These results provide new insights into the biogeography and genetic diversity of H. taeniaeformis in a new geographical area, enhancing our understanding of its evolutionary history.
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- 2024
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5. Optical and Electrical Characterization of Poly(3-Decylthiophene) Thin Films: Chloroform Sensor
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André V. S. Simõis, Nyara D. Ferreira, Maria E. R. S. Medina, Luiz A. R. Junior, Marcelo S. Borro, and Clarissa A. Olivati
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drop casting ,gas sensor ,chloroform ,Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
Conjugated polymers have attracted considerable attention to the organic electronics field, due to their properties and a variety of potential areas of application, such as solar cells, OLEDs, sensors, and transistors. In the sensor area, the study of chloroform gained prominence due to its toxicity and effects on the human body, such as damage to the liver and kidneys. This work aims to study thin films of P3DT in different concentrations, perform their optical, morphological, and electrical characterization, and verify their applicability as chloroform sensors. The thin films and devices are characterized using various techniques: optical characterization is performed through UV-vis spectroscopy, morphological characterization is performed through optical microscopy and electrical characterization is performed in direct current by studying the current vs. voltage curves. Electrical measurements of current vs. time are also performed in order to verify the electrical response of the active layer when exposed to a saturated chloroform atmosphere. Characterization shows expected results, similar to other P3ATs, while gas response initially shows a release in trapped charges, increasing the current, however, as the measure is repeated, the current started to decrease when exposed to the current, caused by a swelling in the polymer’s chain.
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- 2024
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6. Optimizing Price Markup: The Impact of Power Purchase Agreements and Energy Production Uncertainty on the Economic Performance of Onshore and Offshore Wind Farms
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Antonio C. C. Perrelli, Eduardo A. Sodré, André V. R. N. Silva, Caarem D. S. Studzinski, Vinícius F. Silva, Dalton F. G. Filho, Armando T. Neto, and Alex A. B. Santos
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Power Purchase Agreement, Onshore, Offshore, Wind Energy, Internal Rate of Return ,Environmental sciences ,GE1-350 ,Energy industries. Energy policy. Fuel trade ,HD9502-9502.5 - Abstract
Wind energy is rapidly expanding its capacity as part of the global energy transition. To ensure economic viability, wind energy projects increasingly rely on risk mitigation strategies. While Power Purchase Agreements (PPAs) manage spot market price variability, wind farms still face energy production uncertainty, directly impacting the quantity of energy generated. This study presents a comprehensive analysis of the price markup for onshore and offshore wind farms, considering energy production uncertainty under PPA and non-PPA scenarios. The study examines key metrics such as equilibrium prices, price markups, Internal Rate of Return (IRR), Net Present Value (NPV), and their correlation to energy production risk. Results demonstrate that PPAs significantly alter the relationship between price markup and variability. Offshore wind farms can potentially benefit more from PPAs compared to onshore, especially at lower levels of wind energy variability. However, as variability increases, the risk mitigation provided by PPAs diminishes, and both onshore and offshore wind farms may require higher price markups for financial viability. These findings highlight the necessity of carefully designed PPA structures and pricing strategies to ensure long-term competitiveness and sustainability of wind energy projects.
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- 2024
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7. O que nos faz humanos: intersubjetividade na gramática, no discurso e na interação
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Diogo Pinheiro, Augusto Soares da Silva, and André V. Lopes Coneglian
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Philology. Linguistics ,P1-1091 - Abstract
Apresentação à Revista Linguística v.20 n.1
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- 2024
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8. Manufacture and Photoelectrical Characterization of Poly(3-decylthiophene) Thin Films by Drop Casting Technique
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Luiz A. Riga Junior, Maria V. Riga, Amanda M. P. Santos, Maria E. R. S. Medina, Marcelo S. Borro, André V. S. Simõis, and Clarissa A. Olivati
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Drop casting ,Chloroform ,Optoelectronic properties ,Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
Poly(3-decylthiophene) is a polymer with conductive characteristics due to its conjugated polymeric chain. With the search for new applications and improvements of these materials, in sensors, and OPVs, there is a great demand for deeper knowledge about them. This work aims to characterize the P3DT, through analysis of optoelectrical measurements. Using the drop casting technique, thin films were made onto solid substrates. The films were subjected to optical characterization by UV-Vis and optical microscopy. The electrical characterization was obtained by IxV curves and then measuring the photoconductivity through Ixt curves, with a solar simulator. With UV-Vis measurements, it was observed that the absorption of light in the visible spectrum reached a peak of 520 nm in the film, blue-shifted in the solution attributed to the differences in the organization of the polymer chains. The optical microscopy measurements indicate the formation of aggregates with a higher concentration of aggregates observed for the film obtained with a more concentrated solution. Finally, the photoconductivity measurements carried out obtained a positive response to the photo-excitation of the material due to exposure to light, with an increase in current in the film as the photo-exposure cycles were repeated.
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- 2024
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9. Molecular surveillance of potential SARS-CoV-2 reservoir hosts in wildlife rehabilitation centers
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Juan Mena, Christian Hidalgo, Daniela Estay-Olea, Nicole Sallaberry-Pincheira, Antonella Bacigalupo, André V. Rubio, Diego Peñaloza, Carolina Sánchez, Javiera Gómez-Adaros, Valeria Olmos, Javier Cabello, Kendra Ivelic, María José Abarca, Diego Ramírez-Álvarez, Marisol Torregrosa Rocabado, Natalia Durán Castro, Martina Carreño, Gabriela Gómez, Pedro E. Cattan, Galia Ramírez-Toloza, Sofía Robbiano, Carla Marchese, Eduardo Raffo, Paulina Stowhas, Gonzalo Medina-Vogel, Carlos Landaeta-Aqueveque, René Ortega, Etienne Waleckx, Daniel Gónzalez-Acuña, and Gemma Rojo
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Chile ,wildlife conservation ,wildlife rehabilitation centers ,COVID-19 ,SARS-CoV-2 ,Veterinary medicine ,SF600-1100 - Abstract
AbstractBackground The COVID-19 pandemic, caused by SARS-CoV-2 infection, has become the most devastating zoonotic event in recent times, with negative impacts on both human and animal welfare as well as on the global economy. Although SARS-CoV-2 is considered a human virus, it likely emerged from animals, and it can infect both domestic and wild animals. This constitutes a risk for human and animal health including wildlife with evidence of SARS-CoV-2 horizontal transmission back and forth between humans and wild animals.Aim Molecular surveillance in different wildlife rehabilitation centers and wildlife associated institutions in Chile, which are critical points of animal-human interaction and wildlife conservation, especially since the aim of wildlife rehabilitation centers is to reintroduce animals to their original habitat.Materials and Methods The survey was conducted in six WRCs and three wildlife associated institutions. A total of 185 samples were obtained from 83 individuals belonging to 15 different species, including vulnerable and endangered species. Each specimen was sampled with two different swabs: one oropharyngeal or nasopharyngeal according to the nostril diameter, and/or a second rectal sample. RNA was extracted from the samples and two different molecular assays were performed: first, a conventional RT-PCR with pan-coronavirus primers and a second SARS-CoV-2 qPCR targeting the N and S genes.Results All 185 samples were negative for SARS-CoV-2.Clinical relevance This study constitutes the first report on the surveillance of SARS-CoV-2 from wildlife treated in rehabilitation centers in Chile, and supports the biosafety procedures adopted in those centers.
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- 2023
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10. Vertical Stratification of Butterfly Assemblages Persists in Highly Disturbed Forest Fragments of the Brazilian Atlantic Forest
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Denise B. Silva, André V. L. Freitas, Oscar F. Junior, and Jessie P. Santos
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Atlantic Forest ,butterflies ,conservation ,Nymphalidae ,vertical stratification ,Biology (General) ,QH301-705.5 - Abstract
Vertical stratification is a property of forest habitats related to the differential distribution of organisms according to the variation in the conditions, from the understory to the canopy. Here, we aimed to test whether butterfly assemblages from highly disturbed forests maintain the pattern of vertical stratification. We hypothesized that degraded forests would not exhibit vertical stratification due to the low variation in the microhabitat conditions along the vertical gradient, resulting from the canopy openness. To test this, we sampled fruit-feeding butterflies with bait traps, alternately disposed between the understory and canopy of three secondary forest fragments in a very fragmented Atlantic Forest landscape, for one year. We found that the vertical strata differed in terms of species composition, with a high contribution by the nestedness component on the beta diversity spatial variation. The understory assemblages had a higher abundance and were more diverse than the upper stratum. We demonstrated that vertical stratification is maintained even in disturbed forests; however, this does not necessarily provide support for a good quality and functioning ecosystem in these habitats. The butterfly assemblages recorded here are a subset of the species pool that inhabits conserved remnants. Thus, even being represented by species commonly found in disturbed habitats, the dynamic of vertical stratification of assemblages remains.
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- 2024
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11. The Influence of Kinematics on Tennis Serve Speed: An In-Depth Analysis Using Xsens MVN Biomech Link Technology
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André V. Brito, Pedro Fonseca, Mário J. Costa, Ricardo Cardoso, Catarina C. Santos, Jaime Fernandez-Fernandez, and Ricardo J. Fernandes
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3D motion analysis ,serve biomechanics ,kinematic analysis ,inertial measurement system ,Technology ,Biology (General) ,QH301-705.5 - Abstract
An inertial measurement system, using a combination of accelerometers, gyroscopes and magnetometers, is of great interest to capture tennis movements. We have assessed the key biomechanical moments of the serve phases and events, as well as the kinematic metrics during the serve, to analyze their influence on serve speed. Eighteen male competitive tennis players, equipped with the inertial measurement units, performed a prolonged serve game consisting of 12 simulated points. Participants were divided into groups A and B in accordance with their positioning above or below the sample average serve speed. Group A (compared with their counterparts) presented with lower back hip adduction and knee flexion, and a higher leftward thoracic tilt during the impact event (−14.9 ± 6.9 vs. 13.8 ± 6.4, 2.8 ± 5.9 vs. 14.3 ± 13.0 and −28.9 ± 6.3 vs. 28.0 ± 7.3°). In addition, group A exhibited higher maximal angular velocities in the wrist and thorax, as well as a lower maximal angular velocity in the back hip than group B (427.0 ± 99.8 vs. 205.4 ± 9.7, 162.4 ± 81.7 vs. 193.5 ± 43.8, 205.4 ± 9.7 vs. 308.3 ± 111.7, 193.5 ± 43.8 vs. 81.1 ± 49.7°/s). The relevant biomechanical differences during the serve were identified, highlighting the changes in joint angles and angular velocities between the groups, providing meaningful information for coaches and players to improve their serve proficiency.
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- 2024
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12. Reassessment of the type locality of Euptychia stigmatica Godman, 1905, with the description of two new sibling species from Amazonia (Lepidoptera, Nymphalidae, Satyrinae, Satyrini)
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Shinichi Nakahara, Kaylin Kleckner, Eduardo P. Barbosa, Giselle M. Lourenço, Mirna M. Casagrande, Keith R. Willmott, and André V. L. Freitas
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Zoology ,QL1-991 - Abstract
A brief historical review regarding the type locality of Euptychia stigmatica Godman, 1905 was conducted, which suggests that its type locality is actually Rio de Janeiro, Brazil, rather than northeastern Argentina, as previously purported. Consequently, E. stigmatica and its senior synonym E. cyanites Butler, 1871, are regarded to be two species-group names representing a taxon in the euptychiine genus Caeruleuptychia Forster, 1964 known from the Brazilian Atlantic Forest. A lectotype is designated for E. cyanites. Additionally, two closely related species are named and described using an integrative approach with morphological and molecular evidence. Caeruleuptychia harrisi Nakahara & Freitas, sp. nov. and C. aemulatio Nakahara & Willmott, sp. nov. both occur in Amazonia and COI barcode data recovered these taxa as part of the caerulea clade of Caeruleuptychia.
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- 2023
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13. Association between anthropization and rodent reservoirs of zoonotic pathogens in Northwestern Mexico
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Hugo Mendoza, Andrés M. López-Pérez, André V. Rubio, Julio J. Barrón-Rodríguez, Marisa Mazari-Hiriart, Paulina A. Pontifes, Rodolfo Dirzo, and Gerardo Suzán
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Medicine ,Science - Published
- 2024
14. AT 1 inhibition mediated neuroprotection after experimental traumatic brain injury is dependent on neutrophils in male mice
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Ralph Timaru-Kast, Shila P. Coronel-Castello, Tobias J. Krämer, André V. Hugonnet, Michael K. E. Schäfer, Anne Sebastiani, and Serge C. Thal
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Medicine ,Science - Abstract
Abstract After traumatic brain injury (TBI) cerebral inflammation with invasion of neutrophils and lymphocytes is a crucial factor in the process of secondary brain damage. In TBI the intrinsic renin-angiotensin system is an important mediator of cerebral inflammation, as inhibition of the angiotensin II receptor type 1 (AT1) reduces secondary brain damage and the invasion of neutrophil granulocytes into injured cerebral tissue. The current study explored the involvement of immune cells in neuroprotection mediated by AT1 inhibition following experimental TBI. Four different cohorts of male mice were examined, investigating the effects of neutropenia (anti-Ly6G antibody mediated neutrophil depletion; C57BL/6), lymphopenia (RAG1 deficiency, RAG1−/−), and their combination with candesartan-mediated AT1 inhibition. The present results showed that reduction of neutrophils and lymphocytes, as well as AT1 inhibition in wild type and RAG1−/− mice, reduced brain damage and neuroinflammation after TBI. However, in neutropenic mice, candesartan did not have an effect. Interestingly, AT1 inhibition was found to be neuroprotective in RAG1−/− mice but not in neutropenic mice. The findings suggest that AT1 inhibition may exert neuroprotection by reducing the inflammation caused by neutrophils, ultimately leading to a decrease in their invasion into cerebral tissue.
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- 2023
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15. Activity patterns and interactions of rodents in an assemblage composed by native species and the introduced black rat: implications for pathogen transmission
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Rodrigo Salgado, Isabel Barja, María del Carmen Hernández, Basilio Lucero, Ivan Castro-Arellano, Cristian Bonacic, and André V. Rubio
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Chile ,Interspecific interactions ,Rodentia ,Temporal overlap ,Wild reservoirs ,Zoology ,QL1-991 - Abstract
Abstract Background The degree of temporal overlap between sympatric wild hosts species and their behavioral interactions can be highly relevant to the transmission of pathogens. However, this topic has been scantly addressed. Furthermore, temporal overlap and interactions within an assemblage of wild rodents composed of native and introduced species have been rarely discussed worldwide. We assessed the nocturnal activity patterns and interactions between rodent taxa of an assemblage consisting of native species (Oligoryzomys longicaudatus, Abrothrix hirta, and Abrothrix olivaceus) and the introduced black rat (Rattus rattus) in a temperate forest from southern Chile. All rodent species in this study are known hosts for various zoonotic pathogens. Results We found a high nocturnal temporal overlap within the rodent assemblage. However, pairwise comparisons of temporal activity patterns indicated significant differences among all taxa. Rattus rattus showed aggressive behaviors against all native rodents more frequently than against their conspecifics. As for native rodents, agonistic behaviors were the most common interactions between individuals of the same taxon and between individuals of different taxa (O. longicaudatus vs Abrothrix spp.). Conclusions Our findings reveal several interactions among rodent taxa that may have implications for pathogens such as hantaviruses, Leptospira spp., and vector-borne pathogens. Furthermore, their transmission may be facilitated by the temporal overlap observed between rodent taxa.
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- 2022
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16. Enhancing adoptive CD8 T cell therapy by systemic delivery of tumor associated antigens
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Ditte E. Jæhger, Mie L. Hübbe, Martin K. Kræmer, Gael Clergeaud, André V. Olsen, Camilla Stavnsbjerg, Mette N. Wiinholt, Andreas Kjær, Jonas R. Henriksen, Anders E. Hansen, and Thomas L. Andresen
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Medicine ,Science - Abstract
Abstract Adoptive T-cell transfer (ACT) offers a curative therapeutic option for subsets of melanoma and hematological cancer patients. To increase response rates and broaden the applicability of ACT, it is necessary to improve the post-infusion performance of the transferred T cells. The design of improved treatment strategies includes transfer of cells with a less differentiated phenotype. Such T cell subsets have high proliferative potential but require stimulatory signals in vivo to differentiate into tumor-reactive effector T cells. Thus, combination strategies are needed to support the therapeutic implementation of less differentiated T cells. Here we show that systemic delivery of tumor-associated antigens (TAAs) facilitates in vivo priming and expansion of previously non-activated T cells and enhance the cytotoxicity of activated T cells. To achieve this in vivo priming, we use flexible delivery vehicles of TAAs and a TLR7/8 agonist. Contrasting subcutaneous delivery systems, these vehicles accumulate TAAs in the spleen, thereby achieving close proximity to both cross-presenting dendritic cells and transferred T cells, resulting in robust T-cell expansion and anti-tumor reactivity. This TAA delivery platform offers a strategy to safely potentiate the post-infusion performance of T cells using low doses of antigen and TLR7/8 agonist, and thereby enhance the effect of ACT.
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- 2021
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17. Airfoil tonal noise reduction by roughness elements Part I -- Experimental investigation
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Alva, Elías, Yuan, Zhenyang, Araújo, Tiago B., Amaral, Filipe R. do, Hanifi, Ardeshir, and Cavalieri, André V. G.
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Physics - Fluid Dynamics - Abstract
Laminar separation bubbles around airfoils lead to the growth of instability waves, which enhances to acoustic scattering at the trailing-edge, forming a feedback loop that produces to tonal noise. To reduce the trailing-edge tonal noise, an array of roughness elements was used over a NACA0012 airfoil, at low angles of attack and moderate Reynolds number. Aeroacoustics and flow visualization experiments were performed for four configurations: a baseline smooth airfoil, two configurations with roughness elements on either airfoil surface (pressure side or suction side), and a fourth configuration with roughness elements at both airfoil surfaces. The roughness elements are made up of a row of spanwise periodically spaced cylinders, which were placed close to the mid-chord position. It is expected the proposed array of roughness elements stabilizes the Kelvin-Helmholtz instability mechanism that is present on the separated shear layer through the induction of streak structures. The separation bubble is assessed using oil flow visualizations, and the cases with roughness elements show the generation of streaks downstream of the array cylinders, disrupting the separation bubble. Acoustic measurements results show a decrease, and in some cases the total suppression, of the tonal noise at Reynolds numbers ranging from 0.6$\times$10$^5$ to 2.5$\times$10$^5$, and angles of attack ranging from 0 to 4 degrees., Comment: 20 pages, 17 figures
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- 2024
18. Airfoil Tonal Noise Reduction by Roughness Elements. Part II -- Direct Simulations
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Yuan, Zhenyang, Alva, Elías, de Araújo, Tiago B., Cavalieri, André V. G., and Hanifi, Ardeshir
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Physics - Fluid Dynamics - Abstract
In a combined experimental and numerical effort we investigate airfoil tonal noise generation and reduction. The means of noise control are streak generators in form of cylindrical roughness elements. These elements are placed periodically along the span of airfoil at the mid chord streamwise position. Experiments are performed for a wide range of Reynolds number and angle of attack in a companion work (Alva et al. 2024). In the present work we concentrate on numerical investigations for a further investigation of selected cases. We have performed wall-resolved large-eddy simulations for a NACA 0012 airfoil at zero angle of attack and Mach 0.3. Two Reynolds numbers (80,000 and 100,000) have been investigated, showing acoustic results consistent with experiments at the same Reynolds but lower Mach numbers. Roughness elements attenuate tones in the acoustic field and, for the higher Reynolds number, suppress them. Through Fourier decomposition and spectral POD analysis of streamwise velocity data, dominating structures have been identified. Further, the coupling between structures generated by surface roughness and instability modes (Kelvin-Helmholtz) of shear layer has been identified through stability analysis, suggesting stabilisation mechanisms by which the sound generation by the airfoil is reduced by the roughness elements., Comment: 24 pages, 15 figures
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- 2024
19. Turbulence suppression in plane Couette flow using reduced-order models
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Maia, Igor A. and Cavalieri, André V. G.
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Physics - Fluid Dynamics - Abstract
We explore a reduced-order model (ROM) of plane Couette flow with a view to performing turbulence control. The ROM is derived through Galerkin projections of the incompressible Navier-Stokes (NS) system onto a basis composed of controllability modes, truncated to a few streamwise and spanwise wavenumbers. Such ROMs were found to reproduce key aspects of nonlinear turbulence dynamics in Couette flow with only a few hundreds degrees of freedom. Here we use the ROM to devise a control strategy. For that, we consider a ROM with an extra forcing term, consisting in a steady body force. The spatial structure of the forcing is given by a linear combination of Stokes modes, optimised using a gradient-descent algorithm in order to minimise the total fluctuation energy. The optimisation is performed at different Reynolds numbers, with the optimal forcing leading to laminarisation of the flow in all cases. The forcing mechanism acts by strongly reducing the shear in a large central portion of the channel. This disrupts the dynamics of large-scale streaks and rolls and hinders the main energy input to the system. When the forcing is active, the flow reaches a new laminar state which is linearly stable and whose linear transient growth is substantially reduced with respect to that of laminar Couette flow. These features prompt the flow to return to the laminar Couette state when the forcing is switched off. Body forces optimised in the ROM are subsequently applied to the full NS system in direct numerical simulations (DNS) for the same flow configurations. The same control mechanisms are observed in the DNS, where laminarisation is also achieved. The present work opens up interesting possibilities for turbulence control. We show that the ROMs provide an effective framework to design turbulence control strategies, despite the high degree of truncation with respect to the full system.
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- 2024
20. Epidemiological Analysis of Foot and Ankle Injuries in Athletes: Experience of a Single Specialized Center
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Lucas Plens de Britto Costa, Fernando G. Corrêa, Henrique CM. Cunha, Fernando C. Raduan MD, Eduardo S. Maciel, André V. Lemos MD, Caio A. Nery MD, and Nacime SB Mansur MD
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Orthopedic surgery ,RD701-811 - Abstract
Category: Sports; Ankle Introduction/Purpose: The number of professional and amateur athletes has increased, consequently leading to an increase in the incidence of sports injuries. Understanding the epidemiological profile of foot and ankle's injuries in athletes is relevant for the prevention and treatment its occurrence. As far as we know, there is a lack of studies that report the epidemiological profile of athletes with foot and ankle disorders considering different sports. The aim of this study is to describe the epidemiology of foot and ankle injuries in athletes treated at an outpatient clinic specializing in injuries resulting from sports practice. The primary hypothesis is that ankle instability is the most frequent injury in athletes in the foot and ankle specialty outpatient clinic. Methods: Observational, retrospective, descriptive and comparative level IV of evidence study. The sample consisted of patients treated at an outpatient clinic specializing in foot and ankle injuries in sport, between January 1, 2015 and December 31, 2020. Three certified orthopedic physicians reviewed the charts and documented patient demographics, sport, diagnosis and lesion laterality. Age was analyzed according to age groups. The inclusion criteria were patients practicing amateurs or sports professionals of all age groups. We only count the first visits and the main modality and diagnosis of the patient. Exclusion criteria were insufficient data documented in chart, injuries that did not occur secondary to sports practice, and patients with conditions unrelated to the ankle and foot. Statistical analyzes were performed using software: SPSS V20, Minitab 16 and Excel Office 2010. We performed a multivariate logistic regression analysis to verify the association of gender, age and laterality with the main injuries documented. Results: A total of 763 patients (387 men and 376 women) met the inclusion criteria. The mean age was 35 years (SD= +-14.1; min=8.9; max=77). The most prevalent age group was young adults with 51.7% and the least prevalent was children with 1.4%. The most prevalent diseases were chronic lateral ankle instability (n=134, 17.6%), acute lateral ankle sprain (n=120, 15.7%) and plantar fasciitis (n=69, 9%). The multivariable analysis by logistic regression identified as a risk factor for lateral ankle instability the age group of young adults and females. In acute lateral ankle sprain, age was identified as a risk factor with statistical significance. In overuse injuries, only the female gender was evidenced as a risk factor. In non-insertional Achilles tendinopathy, bilaterality was associated as a risk factor with disease while in insertional Achilles tendinopathy, only the male gender was identified as a risk factor, as well as in Achilles tendon rupture. Conclusion: The literature specifically describing foot and ankle injuries during sport is limited, despite being highly prevalent injuries. Our work correlated several factors such as age, gender and laterality with specific sports through multivariate analysis, adding epidemiological data to the literature that help in the prevention and treatment of foot and ankle injuries in sports.
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- 2022
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21. Exploring Regularization Methods for Domain Generalization in Accelerometer-Based Human Activity Recognition
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Nuno Bento, Joana Rebelo, André V. Carreiro, François Ravache, and Marília Barandas
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Human Activity Recognition ,deep learning ,Domain Generalization ,regularization ,accelerometer ,Chemical technology ,TP1-1185 - Abstract
The study of Domain Generalization (DG) has gained considerable momentum in the Machine Learning (ML) field. Human Activity Recognition (HAR) inherently encompasses diverse domains (e.g., users, devices, or datasets), rendering it an ideal testbed for exploring Domain Generalization. Building upon recent work, this paper investigates the application of regularization methods to bridge the generalization gap between traditional models based on handcrafted features and deep neural networks. We apply various regularizers, including sparse training, Mixup, Distributionally Robust Optimization (DRO), and Sharpness-Aware Minimization (SAM), to deep learning models and assess their performance in Out-of-Distribution (OOD) settings across multiple domains using homogenized public datasets. Our results show that Mixup and SAM are the best-performing regularizers. However, they are unable to match the performance of models based on handcrafted features. This suggests that while regularization techniques can improve OOD robustness to some extent, handcrafted features remain superior for domain generalization in HAR tasks.
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- 2023
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22. Quantifying the Displacement of Data Matrix Code Modules: A Comparative Study of Different Approximation Approaches for Predictive Maintenance of Drop-on-Demand Printing Systems
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Peter Bischoff, André V. Carreiro, Christiane Schuster, and Thomas Härtling
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data matrix ,pattern recognition ,drop deviation ,code recognition ,quality assessment ,predictive maintenance ,Photography ,TR1-1050 ,Computer applications to medicine. Medical informatics ,R858-859.7 ,Electronic computers. Computer science ,QA75.5-76.95 - Abstract
Drop-on-demand printing using colloidal or pigmented inks is prone to the clogging of printing nozzles, which can lead to positional deviations and inconsistently printed patterns (e.g., data matrix codes, DMCs). However, if such deviations are detected early, they can be useful for determining the state of the print head and planning maintenance operations prior to reaching a printing state where the printed DMCs are unreadable. To realize this predictive maintenance approach, it is necessary to accurately quantify the positional deviation of individually printed dots from the actual target position. Here, we present a comparison of different methods based on affinity transformations and clustering algorithms for calculating the target position from the printed positions and, subsequently, the deviation of both for complete DMCs. Hence, our method focuses on the evaluation of the print quality, not on the decoding of DMCs. We compare our results to a state-of-the-art decoding algorithm, adopted to return the target grid positions, and find that we can determine the occurring deviations with significantly higher accuracy, especially when the printed DMCs are of low quality. The results enable the development of decision systems for predictive maintenance and subsequently the optimization of printing systems.
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- 2023
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23. In Case of Fire, Escape or Die: A Trait-Based Approach for Identifying Animal Species Threatened by Fire
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Eugênia K. L. Batista, José E. C. Figueira, Ricardo R. C. Solar, Cristiano S. de Azevedo, Marina V. Beirão, Christian N. Berlinck, Reuber A. Brandão, Flávio S. de Castro, Henrique C. Costa, Lílian M. Costa, Rodrigo M. Feitosa, André V. L. Freitas, Guilherme H. S. Freitas, Conrado A. B. Galdino, José E. Santos Júnior, Felipe S. Leite, Leonardo Lopes, Sandra Ludwig, Maria C. do Nascimento, Daniel Negreiros, Yumi Oki, Henrique Paprocki, Lucas N. Perillo, Fernando A. Perini, Fernando M. Resende, Augusto H. B. Rosa, Luiz F. Salvador, Larissa M. Silva, Luis F. Silveira, Og DeSouza, Emerson M. Vieira, and Geraldo Wilson Fernandes
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fire ecology ,resilience ,sensitivity ,functional traits ,savanna ecosystems ,species vulnerability ,Physics ,QC1-999 - Abstract
Recent studies have argued that changes in fire regimes in the 21st century are posing a major threat to global biodiversity. In this scenario, incorporating species’ physiological, ecological, and evolutionary traits with their local fire exposure might facilitate accurate identification of species most at risk from fire. Here, we developed a framework for identifying the animal species most vulnerable to extinction from fire-induced stress in the Brazilian savanna. The proposed framework addresses vulnerability from two components: (1) exposure, which refers to the frequency, extent, and magnitude to which a system or species experiences fire, and (2) sensitivity, which reflects how much species are affected by fire. Sensitivity is based on biological, physiological, and behavioral traits that can influence animals’ mortality “during” and “after” fire. We generated a Fire Vulnerability Index (FVI) that can be used to group species into four categories, ranging from extremely vulnerable (highly sensible species in highly exposed areas), to least vulnerable (low-sensitivity species in less exposed areas). We highlight the urgent need to broaden fire vulnerability assessment methods and introduce a new approach considering biological traits that contribute significantly to a species’ sensitivity alongside regional/local fire exposure.
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- 2023
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24. Habitat generalist species constrain the diversity of mimicry rings in heterogeneous habitats
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Irina Birskis-Barros, André V. L. Freitas, and Paulo R. Guimarães
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Medicine ,Science - Abstract
Abstract How evolution creates and maintains trait patterns in species-rich communities is still an unsolved topic in evolutionary ecology. One classical example of community-level pattern is the unexpected coexistence of different mimicry rings, each of which is a group of mimetic species with the same warning signal. The coexistence of different mimicry rings in a community seems paradoxical because selection among unpalatable species should favor convergence to a single warning pattern. We combined mathematical modeling based on network theory and numerical simulations to explore how different types of selection, such as mimetic and environmental selections, and habitat use by mimetic species influence the formation of coexisting rings. We show that when habitat and mimicry are strong sources of selection, the formation of multiple rings takes longer due to conflicting selective pressures. Moreover, habitat generalist species decrease the distinctiveness of different mimicry rings’ patterns and a few habitat generalist species can generate a “small-world effect”, preventing the formation of multiple mimicry rings. These results may explain why the coexistence of mimicry rings is more common in groups of animals that tend towards habitat specialism, such as butterflies.
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- 2021
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25. Butterfly Assemblages Differ among Vegetation Types in Southern Amazonia
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Luísa L. Mota, Jessie P. Santos, Keith R. Willmott, and André V. L. Freitas
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Amazon forest ,environmental heterogeneity ,habitat diversity ,tropical ,Biology (General) ,QH301-705.5 - Abstract
Environmental heterogeneity is considered an important factor supporting the evolution and maintenance of biodiversity. At small scales, such heterogeneity is thought to promote species co-existence through an increase in niche opportunities. Amazonia, the largest and most biodiverse rainforest in the world, presents a large number of vegetation types within its territory. Here, we tested the hypothesis that butterfly assemblages differ among five vegetation types at a small scale (less than 1 km2) in a region of Southern Amazonia. The vegetation types studied were forest gap, terra firme, igapó, semi-deciduous forest, and bamboo forest. The richest and most abundant community was in forest gap; igapó was the least rich, but held the second most abundant community and the only one with nine indicator species instead of two or three. Assemblage composition differed among all vegetation types, with the exception of forest gap and bamboo forest. Different light levels, temperatures, humidity, and host plant availability among vegetation types are likely relevant factors influencing these butterfly assemblages. The results suggest that the presence of various vegetation types in the region promotes the coexistence of butterfly species, and that specific threats to each vegetation type should be addressed to conserve the region’s biodiversity.
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- 2023
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26. Estudo Comparativo da Doença Coronariana Microvascular Causada por Doença de Chagas e por Outras Etiologias
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Felipe Araujo Campos, Mariana L. Magalhães, Henrique Turin Moreira, Rafael B. Pavão, Moyses O. Lima Filho, Igor M. Lago, André V. Badran, João R. A. Chierice, André Schmidt, and José Antonio Marin Neto
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Cardiomiopatia da doença de Chagas ,Doença de Chagas/complicações ,Disfunção Microvascular Coronariana ,Disfunção Ventricular Esquerda ,Escore de Anormalidade Sistólica Parietal ,Fração de Ejeção Ventricular ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Resumo Fundamento A doença de Chagas (DC) constitui uma causa potencial negligenciada de doença microvascular coronariana (DMC). Objetivos Comparar pacientes com DMC relacionada à DC (DMC-DC) com pacientes com DMC ligada a outras etiologias (DMC-OE). Métodos De 1292 pacientes estáveis, encaminhados para angiografia coronária invasiva para elucidar o padrão hemodinâmico e a causa de angina, 247 apresentaram coronárias subepicárdicas normais, e 101 foram incluídos após aplicação dos critérios de exclusão. Desses, 15 compuseram o grupo de DMC-DC e suas características clínicas, hemodinâmicas, angiográficas, e cintilográficas foram comparadas às do grupo de 86 pacientes com DMC-OE. O nível de significância estatística para todas as comparações adotado foi de 0,05. Resultados Pacientes com suspeita de DMC-DC apresentaram características antropométricas, clínicas e angiográficas, além de alterações hemodinâmicas e de perfusão miocárdica estatisticamente comparáveis às detectadas nos 86 pacientes com DMC-OE. Disfunção ventricular diastólica, expressa por elevada pressão telediastólica do ventrículo esquerdo, foi igualmente encontrada nos dois grupos. Entretanto, em comparação a esse grupo com DMC-OE, o grupo com DMC-DC exibiu fração de ejeção ventricular esquerda mais baixa (61,1 ± 11,9 vs 54,8 ± 15,9; p= 0,049) e mais elevado escore de mobilidade da parede ventricular (1,77 ± 0,35 vs 1,18 ± 0,26; p= 0,02). Conclusão A cardiomiopatia crônica da doença de Chagas esteve associada à etiologia de possível doença microvascular coronariana em 15% de amostra de 101 pacientes estáveis, cujo sintoma principal era angina requerendo elucidação por angiografia invasiva. Embora os grupos DMC-DC e DMC-OE apresentassem características clínicas, hemodinâmicas, e de perfusão miocárdica em comum, a disfunção global e segmentar do ventrículo esquerdo foi mais grave nos pacientes com DMC associada à DC em comparação à DMC por outras etiologias. (Arq Bras Cardiol. 2020; 115(6):1094-1101)
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- 2021
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27. LumberChunker: Long-Form Narrative Document Segmentation
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Duarte, André V., Marques, João, Graça, Miguel, Freire, Miguel, Li, Lei, and Oliveira, Arlindo L.
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Computer Science - Computation and Language ,Computer Science - Information Retrieval ,I.2 - Abstract
Modern NLP tasks increasingly rely on dense retrieval methods to access up-to-date and relevant contextual information. We are motivated by the premise that retrieval benefits from segments that can vary in size such that a content's semantic independence is better captured. We propose LumberChunker, a method leveraging an LLM to dynamically segment documents, which iteratively prompts the LLM to identify the point within a group of sequential passages where the content begins to shift. To evaluate our method, we introduce GutenQA, a benchmark with 3000 "needle in a haystack" type of question-answer pairs derived from 100 public domain narrative books available on Project Gutenberg. Our experiments show that LumberChunker not only outperforms the most competitive baseline by 7.37% in retrieval performance (DCG@20) but also that, when integrated into a RAG pipeline, LumberChunker proves to be more effective than other chunking methods and competitive baselines, such as the Gemini 1.5M Pro. Our Code and Data are available at https://github.com/joaodsmarques/LumberChunker
- Published
- 2024
28. Universality of scaled particle spectra in ultrarelativistic heavy-ion collisions
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Muncinelli, Cicero D., Gardim, Fernando G., Chinellato, David D., Denicol, Gabriel S., Giannini, Andre V., Luzum, Matthew, Noronha, Jorge, da Silva, Tiago Nunes, Takahashi, Jun, and Torrieri, Giorgio
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Nuclear Theory ,High Energy Physics - Phenomenology - Abstract
We propose a new observable derived from a centrality-dependent scaling of transverse particle spectra. By removing the global scales of total particle number and mean transverse momentum, we isolate the shape of the spectrum. In hydrodynamic simulations, while the multiplicity and mean transverse momentum fluctuate significantly, the scaled spectrum is found to be almost constant even at an event-by-event level and after resonance decays. This universality survives when averaging over events in each centrality bin before scaling. We then investigate the presence of this scaling in experimental data from the ALICE collaboration in Pb-Pb, Xe-Xe, and p-Pb collisions. We find a remarkable universality in the experimentally observed scaled spectra at low transverse momentum, compatible with hydrodynamic predictions. The data show a minor breaking of universality at large transverse momentum and hints of evolution with the system size that are not seen in simulations. Our results motivate further theoretical and experimental investigations of this new observable to bring to light the collective and non-collective behavior encoded in the transverse particle spectrum of different collision systems., Comment: V1: 6 pages, 3 figures
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- 2024
29. The roles of hybridization and habitat fragmentation in the evolution of Brazil’s enigmatic longwing butterflies, Heliconius nattereri and H. hermathena
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Darli Massardo, Nicholas W. VanKuren, Sumitha Nallu, Renato R. Ramos, Pedro G. Ribeiro, Karina L. Silva-Brandão, Marcelo M. Brandão, Marília B. Lion, André V. L. Freitas, Márcio Z. Cardoso, and Marcus R. Kronforst
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Heliconius ,Hybridization ,Introgression ,Mutation load ,Mimicry ,Phylogenetics ,Biology (General) ,QH301-705.5 - Abstract
Abstract Background Heliconius butterflies are widely distributed across the Neotropics and have evolved a stunning array of wing color patterns that mediate Müllerian mimicry and mating behavior. Their rapid radiation has been strongly influenced by hybridization, which has created new species and allowed sharing of color patterning alleles between mimetic species pairs. While these processes have frequently been observed in widespread species with contiguous distributions, many Heliconius species inhabit patchy or rare habitats that may strongly influence the origin and spread of species and color patterns. Here, we assess the effects of historical population fragmentation and unique biology on the origins, genetic health, and color pattern evolution of two rare and sparsely distributed Brazilian butterflies, Heliconius hermathena and Heliconius nattereri. Results We assembled genomes and re-sequenced whole genomes of eight H. nattereri and 71 H. hermathena individuals. These species harbor little genetic diversity, skewed site frequency spectra, and high deleterious mutation loads consistent with recent population bottlenecks. Heliconius hermathena consists of discrete, strongly isolated populations that likely arose from a single population that dispersed after the last glacial maximum. Despite having a unique color pattern combination that suggested a hybrid origin, we found no genome-wide evidence that H. hermathena is a hybrid species. However, H. hermathena mimicry evolved via introgression, from co-mimetic Heliconius erato, of a small genomic region upstream of the color patterning gene cortex. Conclusions Heliconius hermathena and H. nattereri population fragmentation, potentially driven by historical climate change and recent deforestation, has significantly reduced the genetic health of these rare species. Our results contribute to a growing body of evidence that introgression of color patterning alleles between co-mimetic species appears to be a general feature of Heliconius evolution.
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- 2020
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30. Interpreting pathways to discover cancer driver genes with Moonlight
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Antonio Colaprico, Catharina Olsen, Matthew H. Bailey, Gabriel J. Odom, Thilde Terkelsen, Tiago C. Silva, André V. Olsen, Laura Cantini, Andrei Zinovyev, Emmanuel Barillot, Houtan Noushmehr, Gloria Bertoli, Isabella Castiglioni, Claudia Cava, Gianluca Bontempi, Xi Steven Chen, and Elena Papaleo
- Subjects
Science - Abstract
Identification of cancer driver genes, especially those that can act as tumour suppressors or oncogenes depending on context, remains a challenge. Here, the authors introduce Moonlight, a tool that integrates multi-omic data to address this challenge and identify numerous dual-role cancer genes.
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- 2020
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31. Ultrasound-assisted transesterification of soybean oil using low power and high frequency and no external heating source
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Pâmella A. Oliveira, Raphaela M. Baesso, Gabriel C. Morais, André V. Alvarenga, and Rodrigo P.B. Costa-Félix
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Biodiesel ,Ultrasound assisted ,Transesterification ,Cavitation ,Measurement uncertainty ,Chemistry ,QD1-999 ,Acoustics. Sound ,QC221-246 - Abstract
In this work, high frequency and low power ultrasound without external heating source and mechanical stirring in biodiesel production were studied. Transesterification of soybean oil with methanol and catalyzed by KOH was investigated using ultrasound equipment and ultrasonic transducer. The effect of ultrasonic output power (3 W–9 W), ultrasonic frequency (1 MHz and 3 MHz), and alcohol to oil molar ratio (6:1 and 8:1) have been investigated. The increase in ultrasonic power provided higher conversion rates. In addition, higher conversion rates were obtained by increasing the ultrasonic frequency from 1 MHz to 3 MHz (48.7% to 79.5%) for the same reaction time. Results also indicate that the speed of sound can be used to evaluate the produced biodiesel qualitatively. Further, the ultrasound system presented electric consumption (46.2 W∙h) four times lower than achieved using the conventional method (211.7 W∙h and 212.3 W∙h). Thus, biodiesel production using low power ultrasound in the MHz frequency range is a promising technology that could contribute to biodiesel production processes.
- Published
- 2021
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32. Comparing Handcrafted Features and Deep Neural Representations for Domain Generalization in Human Activity Recognition
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Nuno Bento, Joana Rebelo, Marília Barandas, André V. Carreiro, Andrea Campagner, Federico Cabitza, and Hugo Gamboa
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human activity recognition ,deep learning ,domain generalization ,accelerometer ,Chemical technology ,TP1-1185 - Abstract
Human Activity Recognition (HAR) has been studied extensively, yet current approaches are not capable of generalizing across different domains (i.e., subjects, devices, or datasets) with acceptable performance. This lack of generalization hinders the applicability of these models in real-world environments. As deep neural networks are becoming increasingly popular in recent work, there is a need for an explicit comparison between handcrafted and deep representations in Out-of-Distribution (OOD) settings. This paper compares both approaches in multiple domains using homogenized public datasets. First, we compare several metrics to validate three different OOD settings. In our main experiments, we then verify that even though deep learning initially outperforms models with handcrafted features, the situation is reversed as the distance from the training distribution increases. These findings support the hypothesis that handcrafted features may generalize better across specific domains.
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- 2022
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33. Study of the Effect of Solvent on the Conductivity of Langmuir-Schaefer Films of Poly(Fullerene)s
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Lucas K. M. Roncaselli, Edilene A. Silva, Hasina H. Ramanitra, Meera Stephen, André V. S. Simõis, Didier Bégué, Deuber Lincon Silva Agostini, Roger C. Hiorns, and Clarissa A. Olivati
- Subjects
Langmuir ,poly-fullerenes ,solvents ,conductivity ,thin films ,Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
The present work aims to prepare and characterize very thin films of poly(fullerene)s in order to investigate their electrical properties and the influence of xylene and chloroform solvents on these materials. The fullerenes studied were phenyl-C61-butyric acid methyl ester (PCBM), oligo{(phenyl-C61-butyric acid methyl ester)-alt-[1,4-bis(bromomethyl)-2,5-bis(octyloxy)benzene]} (OPCBMMB) and poly{[bispyrrolidino(phenyl-C61-butyric acid methyl ester)]-alt-[2,5-bis(octyloxy) benzene]} (PPCBMB), along with poly(3-hexylthiophene) (P3HT). The Langmuir-Schaeffer technique was used to prepare films, which were deposited on interdigitated gold substrates, and electrically characterized, with emphasis on the study of transport, conductivity and mobility mechanisms with respect to the solvents used. We found that the addition of P3HT significantly increased the conductivity of these materials. The xylene cast PPCBM, in both pure and mixed forms under dark conditions, presented the best conductivity results with respect to the other materials. However, when chloroform was used, it was found that OPCBMMB in both pure and mixed forms under light, exhibited the best conductivities. This is the first treatment, to our knowledge, of the impact of solvents on the electronic properties of poly(fullerene)s.
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- 2021
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34. Sinopsis de las especies del género Bacopa (Plantaginaceae, Gratioleae) de Paraguay y sus estados de conservación
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Maria de las Mercedes Sosa, Javier E. Florentín, and André V. Scatigna
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Bacopa ,estado de conservación ,Gratioleae ,Paraguay ,taxonomía ,Science ,Botany ,QK1-989 - Abstract
Introducción y objetivos: Bacopa (Plantaginaceae) representa el género con mayor número de especies de la tribu Gratioleae, ocupando una gran diversidad de ambientes húmedos en Sudamérica. El objetivo de este estudio es contribuir al conocimiento morfológico y taxonómico de las especies de Bacopa de Paraguay, aportando una clave de identificación para los taxones aceptados, descripciones morfológicas, ilustraciones botánicas, mapas de distribución, observaciones y estado de conservación a nivel de país. M&M: Los datos obtenidos se basan en el trabajo de campo y el examen de especímenes de herbario. El estado de conservación de las especies se evaluó en Paraguay, teniendo en cuenta sus distribuciones (criterio B), de acuerdo con las directrices de la UICN. Resultados/Conclusiones: Se registran para Paraguay 15 especies de Bacopa, una con dos variedades. Se citan los primeros registros de Bacopa australis y B. stricta para el país. Se presentan preliminarmente los estados de conservación de las especies y evaluaciones de distribución paraguaya. De los 15 taxones confirmados para Paraguay, 13 se encuentran con categoría de amenaza, 12 están en peligro (EN) y B. verticillata en peligro crítico (CR). Las especies se distribuyen en cinco ecorregiones, de las cuales el mayor número de especies (13) se encuentra en la región del Chaco Húmedo.
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- 2021
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35. Immature stages of the Selaginella-feeding Euptychia mollina (Nymphalidae: Satyrinae) from the Brazilian Amazon
- Author
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André V. L. Freitas, Luísa L. Mota, Eduardo P. Barbosa, and Junia Y. O. Carreira
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Zoology ,QL1-991 - Abstract
The present paper describes the immature stages of the Neotropical satyrine butterfly Euptychia mollina (Hübner, [1813]) from the Brazilian Amazon Forest. Eggs were laid singly on the under surface of the fronds of its host plant, Selaginella sp. (Bryophyta: Selaginellaceae). Larvae are solitary in all instars, presenting a color pattern and shape that make them cryptic on its host plant. The pupa is short, smooth and varies from rusty brown to green. Despite the lack of a close phylogenetic relationship, larvae of Euptychia are very similar to those of the paleotropical satyrines Ragadia and Acrophtalmia, suggesting that camouflage is likely to be one of the factors explaining the similarities among them.
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- 2019
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36. Selective Synthesis of Levulinic Ester from Furfural Catalyzed by Hierarchical Zeolites
- Author
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Sancler C. Vasconcelos, Luiz F. C. Pinhel, Vinicius G. C. Madriaga, Vinicius Rossa, Leyliane G. S. Batinga, Domingos S. A. Silva, Rodrigo D. dos Santos, André V. H. Soares, Ernesto A. Urquieta-González, Fabio Barboza Passos, Rajender S. Varma, and Thiago M. Lima
- Subjects
hierarchical zeolite ,furfural ,levulinic ester ,dealumination ,desilication ,Chemical technology ,TP1-1185 ,Chemistry ,QD1-999 - Abstract
Furfural is a platform molecule that can be catalytically converted using a cascade series of reactions into levulinic esters, essential compounds used as fuel additives. Bifunctional catalysts containing Lewis and Brønsted acid sites such as zeolites are commonly used for these conversions. However, microporous zeolites often present diffusional restriction due to the size similarity of furfural and other molecules to the zeolites’ micropores. Thus, incorporating mesopores in these materials through post-synthetic protocols is a promising pathway to circumventing these limitations. This study presents the creation of hierarchical beta and mordenite using Si or Al removal and their employment in the furfural conversion to isopropyl levulinate (PL). Mordenite zeolite did not produce satisfactory mesopores, while the beta was more efficient in generating them by both acid and alkaline treatments. Beta zeolite treated in an alkaline solution presented larger mesopores (14.9 and 34.0 nm), maintaining a total acidity value close to its parent zeolite and a higher Lewis/Brønsted ratio. The combination of these features led to an improved diffusion of bulkier products and the highest furfural conversion (94%) and PL selectivity (90%), suggesting that a post-modification of beta zeolites produced efficient catalysts for upgrading abundantly available furfural.
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- 2022
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37. Magnetoliposomes Containing Multicore Nanoparticles and a New Antitumor Thienopyridine Compound with Potential Application in Chemo/Thermotherapy
- Author
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Fábio A. C. Lopes, André V. F. Fernandes, Juliana M. Rodrigues, Maria-João R. P. Queiroz, Bernardo G. Almeida, Ana Pires, André M. Pereira, João P. Araújo, Elisabete M. S. Castanheira, Ana Rita O. Rodrigues, and Paulo J. G. Coutinho
- Subjects
multicore magnetic nanoparticles ,magnetoliposomes ,magnetic hyperthermia ,antitumor thienopyridine derivative ,chemotherapy ,Biology (General) ,QH301-705.5 - Abstract
Multicore magnetic nanoparticles of manganese ferrite were prepared using carboxymethyl dextran as an agglutinating compound or by an innovative method using melamine as a cross-coupling agent. The nanoparticles prepared using melamine exhibited a flower-shape structure, a saturation magnetization of 6.16 emu/g and good capabilities for magnetic hyperthermia, with a specific absorption rate (SAR) of 0.14 W/g. Magnetoliposome-like structures containing the multicore nanoparticles were prepared, and their bilayer structure was confirmed by FRET (Förster Resonance Energy Transfer) assays. The nanosystems exhibited sizes in the range of 250–400 nm and a low polydispersity index. A new antitumor thienopyridine derivative, 7-[4-(pyridin-2-yl)-1H-1,2,3-triazol-1-yl]thieno[3,2-b]pyridine, active against HeLa (cervical carcinoma), MCF-7 (breast adenocarcinoma), NCI-H460 (non-small-cell lung carcinoma) and HepG2 (hepatocellular carcinoma) cell lines, was loaded in these nanocarriers, obtaining a high encapsulation efficiency of 98 ± 2.6%. The results indicate that the new magnetoliposomes can be suitable for dual cancer therapy (combined magnetic hyperthermia and chemotherapy).
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- 2022
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38. Unlocking the Potential of Large Language Models for Clinical Text Anonymization: A Comparative Study
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Pissarra, David, Curioso, Isabel, Alveira, João, Pereira, Duarte, Ribeiro, Bruno, Souper, Tomás, Gomes, Vasco, Carreiro, André V., and Rolla, Vitor
- Subjects
Computer Science - Computation and Language ,Computer Science - Artificial Intelligence ,Computer Science - Cryptography and Security ,Computer Science - Machine Learning ,I.2.7 - Abstract
Automated clinical text anonymization has the potential to unlock the widespread sharing of textual health data for secondary usage while assuring patient privacy and safety. Despite the proposal of many complex and theoretically successful anonymization solutions in literature, these techniques remain flawed. As such, clinical institutions are still reluctant to apply them for open access to their data. Recent advances in developing Large Language Models (LLMs) pose a promising opportunity to further the field, given their capability to perform various tasks. This paper proposes six new evaluation metrics tailored to the challenges of generative anonymization with LLMs. Moreover, we present a comparative study of LLM-based methods, testing them against two baseline techniques. Our results establish LLM-based models as a reliable alternative to common approaches, paving the way toward trustworthy anonymization of clinical text.
- Published
- 2024
39. $D^0$ meson production in $pp$ collisions at large $Q_s^2$
- Author
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Lima, Yuri N., Giannini, André V., and Goncalves, Victor P.
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High Energy Physics - Phenomenology ,High Energy Physics - Experiment - Abstract
The impact of the non-linear effects in the QCD dynamics on the observables is directly related to the magnitude of the saturation scale $Q_s$, which is predicted to increase with the energy, rapidity and multiplicity. In this paper, we investigate the $D^0$ meson production in $pp$ collisions at forward rapidities and/or high multiplicities considering the Color Glass Condensate (CGC) formalism and the solutions of the running coupling Balitsky - Kovchegov (BK) equation. The contributions of gluon - and charm - initiated processes are taken into account, and a comparison with the current LHCb data is performed. The impact of an intrinsic charm component in the proton's wave function is also estimated. Predictions for the self-normalized yields of $D^0$ mesons as a function of the multiplicity of coproduced charged hadrons are presented, considering $pp$ collisions at $\sqrt{s} = 13$ TeV and different values of the meson rapidity. A comparison with the predictions for the kaon and isolated photon production is performed. Our results indicate that a future experimental analysis of the $D^0$ meson production at forward rapidities and high multiplicities can be useful to probe the CGC formalism and to disentangle the contribution of initial - and final - state effects., Comment: 14 pages, 13 figures
- Published
- 2024
40. Accessing the speed of sound in relativistic ultracentral nucleus-nucleus collisions using the mean transverse momentum
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Gardim, Fernando G., Giannini, Andre V., and Ollitrault, Jean-Yves
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Nuclear Theory ,High Energy Physics - Phenomenology ,Nuclear Experiment - Abstract
It has been argued that the speed of sound of the strong interaction at high temperature can be measured using the variation of the mean transverse momentum with the particle multiplicity in ultracentral heavy-ion collisions. We test this correspondence by running hydrodynamic simulations at zero impact parameter with several equations of state, at several colliding energies from 0.2 TeV to 15 TeV per nucleon pair. The correspondence is found to be precise and robust for a smooth, boost-invariant fluid and an ideal detector. We discuss the differences between this ideal setup and an actual experiment. We conclude that the extraction of the speed of sound from data is reliable, and that the main uncertainty comes from our poor knowledge of the distribution of density fluctuations at the early stages of the collision., Comment: v2: 8 pages, 4 figures. Added new section IV - E. Matches the published version
- Published
- 2024
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41. $B$-meson production at forward rapidities in $pp$ collisions at the LHC: Estimating the intrinsic bottom contribution
- Author
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Lima, Yuri N., Goncalves, Victor P., and Giannini, André V.
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High Energy Physics - Phenomenology ,High Energy Physics - Experiment - Abstract
The production of $B$ mesons at forward rapidities is strongly sensitive to the behavior of the gluon and bottom distribution functions for small and large values of the Bjorken - $x$ variable. In this exploratory study, we estimate the cross - section for the $B^{\pm}$ meson production in the kinematic range probed by the LHCb detector and that will be analyzed by the future Forward Physics Facility (FPF) considering the hybrid formalism, the solution of the running coupling Balitsky - Kovchegov equation and distinct descriptions for the bottom distribution function. We assume an ansatz for the intrinsic bottom component in the proton wave function, and estimate its impact on the transverse momentum, rapidity and Feynman - $x$ distributions. Our results indicate that the presence of an intrinsic bottom strongly modifies the magnitude of the cross - section at ultra - forward rapidities ($y \ge 6$), which implies an enhancement of the $B^{\pm}$ production at the FPF. Possible implications on the prompt neutrino flux at ultra-high energies are also briefly discussed., Comment: 8 pages, 5 figures. Version to be published in European Physical Journal C
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- 2024
42. Improved objective Bayesian estimator for a PLP model hierarchically represented subject to competing risks under minimal repair regime.
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Francisco Louzada, José A Cuminato, Oscar M H Rodriguez, Vera L D Tomazella, Paulo H Ferreira, Pedro L Ramos, Eder A Milani, Gustavo Bochio, Ivan C Perissini, Oilson A Gonzatto Junior, Alex L Mota, Luis F A Alegría, Danilo Colombo, Eduardo A Perondi, André V Wentz, Anselmo L Silva Júnior, Dante A C Barone, Hugo F L Santos, and Marcus V C Magalhães
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Medicine ,Science - Abstract
In this paper, we propose a hierarchical statistical model for a single repairable system subject to several failure modes (competing risks). The paper describes how complex engineered systems may be modelled hierarchically by use of Bayesian methods. It is also assumed that repairs are minimal and each failure mode has a power-law intensity. Our proposed model generalizes another one already presented in the literature and continues the study initiated by us in another published paper. Some properties of the new model are discussed. We conduct statistical inference under an objective Bayesian framework. A simulation study is carried out to investigate the efficiency of the proposed methods. Finally, our methodology is illustrated by two practical situations currently addressed in a project under development arising from a partnership between Petrobras and six research institutes.
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- 2021
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43. Acoustic Radiation of a Simplified Jet-Flap-Thrust Gate Configuration: Numerical and Experimental Investigation
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Sirotto, José R. L. N., Cordioli, Julio A., Nogueira, Petrônio A. S., Cavalieri, André V. G., Secchi, Maicon, and Wolf, William R.
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- 2024
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44. Brazilian Experience with Zennith – Corin System Total Ankle Replacement
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Daniel Baumfeld MD, André V. Lemos MD, Tiago S. Baumfeld MD, Alexandre L. Godoy-Santos MD, and Caio A. Nery MD
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Orthopedic surgery ,RD701-811 - Abstract
Category: Ankle Arthritis Introduction/Purpose: Total ankle arthroplasty is already a reality in Brazil, although there are few publications of clinical outcomes in our country. The objective of this publication is to evaluate the results of TAA in a series of patients treated with corin system total ankle replacement Methods: 26 TAA were implanted from Jan / 13 to Aug / 16, (26 patients - 15F: 58% / 11M: 42%) (mean age: 55 years: min 37a / max 69a) using the implants Zennith from Corin (UK). Data from the clinical status (VAS, AOFAS, ADM), implant positioning and osteotomies (LTS, tibial slope, Alpha, Beta and Teta angles and distances ‘a’ and ‘b’) were evaluated in addition to the qualitative bone evolution (Peri-prosthetic cysts, sagging and wear of the components). Immediate and late information of associated surgeries, complications, and re-interventions were collected. Figure 1 present pre and post operative image Results: At 31 months of follow-up (min 4m: max 48m), there was a significant improvement in VAS (pre 8: post 2), AOFAS score (pre 37: post 77) and tibio-talar movement arch (pre 12: post 25 ) (P
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- 2020
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45. Brazilian Total Ankle Replacement Experience
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Daniel Baumfeld MD, André V. Lemos MD, César E. Martins MD, and Caio A. Nery MD
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Orthopedic surgery ,RD701-811 - Abstract
Category: Ankle Arthritis Introduction/Purpose: Brazil experiences a late participation in total ankle arthroplasty, which could have positive and negative aspects. The positive view argues about the modern implants that Brazil has received in the past years, skipping the early TAR generation who present more complications and low survival rate in the literature. The negative aspects are related to gap of experience, Brazilian surgeon could not participate in the development of the technique and implants designs during all these years. This paper present the aspects of the Brazilian experience with total ankle replacement since the earliest procedures performed. Methods: Data since the first series of TARs in Brazil were colect from university institution, personal data base from surgeons and previous publication, survivalship, complications, number of each implant and implant availability were recorded. Results: In Brazil, indications for TAR are not so different from around the world, the data we had access demonstrate 65% of post-traumatic arthritis, 26 % of inflammatory arthritis, 2% post-infectious arthritis and 7 % of primary arthritis. In fortheen years 263 surgeries were performed, in different parts of the country, but only one surgeon performed 43 cases (27,3% of the total). Table 1 demonstrate the number of procedures performed per year. Survivor rate of each implant available in the country in the first year were 94%, 86,19% in the second year, 82,84% in the third year, 81,62% in the fourth year and 71,47% in the fifth year. Conclusion: In Brazil there are limited and different ankle arthroplasty systems available for use. The procedure itself continues to be technically demanding and require surgical sophistication and expertise. A national registry to justify the procedure indication; report the outcomes and survivorship has not been developed. This procedure is growing around the county, as well as the surgeon experience, but we should remember that TAR is not for every patient and that the appropriate indication, based on the evidence available, is fundamental to obtaining durable and predictable outcomes.
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- 2020
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46. Periodized versus non-periodized swimming training with equal total training load: Physiological, molecular and performance adaptations in Wistar rats.
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Lucas D M Forte, Natália A Rodrigues, André V Cordeiro, Thais de Fante, Laís A P Simino, Adriana S Torsoni, Márcio A Torsoni, Claudio A Gobatto, and Fúlvia B Manchado-Gobatto
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Medicine ,Science - Abstract
This study investigated the effect of non-periodized training performed at 80, 100 and 120% of the anaerobic threshold intensity (AnT) and a linear periodized training model adapted for swimming rats on the gene expression of monocarboxylate transporters 1 and 4 (MCT1 and 4, in soleus and gastrocnemius muscles), protein contents, blood biomarkers, tissue glycogen, body mass, and aerobic and anaerobic capacities. Sixty Wistar rats were randomly divided into 6 groups (n = 10 per group): a baseline (BL; euthanized before training period), a control group (GC; not exercised during the training period), three groups exercised at intensities equivalent to 80, 100 and 120% of the AnT (G80, G100 and G120, respectively) at the equal workload and a linear periodized training group (GPE). Each training program lasted 12 weeks subdivided into three periods: basic mesocycle (6 weeks), specific mesocycle (5 weeks) and taper (1 week). Although G80, G100 and G120 groups were submitted to monotony workload (i.e. non-modulation at intensity or volume throughout the training program), rodents were evaluated during the same experimental timepoints as GPE to be able comparisons. Our main results showed that all training programs were capable to minimize the aerobic capacity decrease promoted by age, which were compared to control group. Rats trained in periodization model had reduced levels of lipid blood biomarkers and increased hepatic glycogen stores compared to all other trained groups. At the molecular level, only expressions of MCT1 in the muscle were modified by different training regimens, with MCT1 mRNA increasing in rats trained at lower intensities (G80), and MCT1 protein content showed higher values in non-periodized groups compared to pre-training and GPE. Here, training at different intensities but at same total workload promoted similar adaptations in rats. Nevertheless, our results suggested that periodized training seems to be optimize the physiological responses of rats.
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- 2020
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47. Periplasm-enriched fractions from Xanthomonas citri subsp. citri type A and X. fuscans subsp. aurantifolii type B present distinct proteomic profiles under in vitro pathogenicity induction.
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Flávia S Zandonadi, Sílvia P Ferreira, André V Alexandrino, Carolina M Carnielli, Juliana Artier, Mariana P Barcelos, Nicole C S Nicolela, Evandro L Prieto, Leandro S Goto, José Belasque, and Maria Teresa Marques Novo-Mansur
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Medicine ,Science - Abstract
The causative agent of Asiatic citrus canker, the Gram-negative bacterium Xanthomonas citri subsp. citri (XAC), produces more severe symptoms and attacks a larger number of citric hosts than Xanthomonas fuscans subsp. aurantifolii XauB and XauC, the causative agents of cancrosis, a milder form of the disease. Here we report a comparative proteomic analysis of periplasmic-enriched fractions of XAC and XauB in XAM-M, a pathogenicity- inducing culture medium, for identification of differential proteins. Proteins were resolved by two-dimensional electrophoresis combined with liquid chromatography-mass spectrometry. Among the 12 proteins identified from the 4 unique spots from XAC in XAM-M (p
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- 2020
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48. Genome-wide scan reveals population stratification and footprints of recent selection in Nelore cattle
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Diercles F. Cardoso, Lucia Galvão de Albuquerque, Christian Reimer, Saber Qanbari, Malena Erbe, André V. do Nascimento, Guilherme C. Venturini, Daiane C. Becker Scalez, Fernando Baldi, Gregório M. Ferreira de Camargo, Maria E. Zerlotti Mercadante, Joslaine N. do Santos Gonçalves Cyrillo, Henner Simianer, and Humberto Tonhati
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Animal culture ,SF1-1100 ,Genetics ,QH426-470 - Abstract
Abstract Background This study aimed at (1) assessing the genomic stratification of experimental lines of Nelore cattle that have experienced different selection regimes for growth traits, and (2) identifying genomic regions that have undergone recent selection. We used a sample of 763 animals genotyped with the Illumina BovineHD BeadChip, among which 674 animals originated from two lines that are maintained under directional selection for increased yearling body weight and 89 animals from a control line that is maintained under stabilizing selection. Results Multidimensional analysis of the genomic dissimilarity matrix and admixture analysis revealed a substantial level of population stratification between the directional selection lines and the stabilizing selection control line. Two of the three tests used to detect selection signatures (F ST, XP-EHH and iHS) revealed six candidate regions with indications of selection, which strongly indicates truly positive signals. The set of identified candidate genes included several genes with roles that are functionally related to growth metabolism, such as COL14A1, CPT1C, CRH, TBC1D1, and XKR4. Conclusions The current study identified genetic stratification that resulted from almost four decades of divergent selection in an experimental Nelore population, and highlighted autosomal genomic regions that present patterns of recent selection. Our findings provide a basis for a better understanding of the metabolic mechanism that underlies the growth traits, which are modified by selection for yearling body weight.
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- 2018
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49. Good Things Come in Larger Packages: Size Matters for Adult Fruit-Feeding Butterfly Dispersal and Larval Diet Breadth
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Geraldo B. Freire, Thayane Silva, Hernani Oliveira, Chloe Collier, Hanna P. Rodrigues, Joao P. Dias, Jessie P. Santos, Onildo J. Marini-Filho, André V. L. Freitas, Angela M. Smilanich, Lee A. Dyer, and Ivone R. Diniz
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body size ,Cerrado ,evolutionary history ,Nymphalidae ,phylogeny ,species traits ,Biology (General) ,QH301-705.5 - Abstract
Introduction: In animals, body size is correlated with many aspects of natural history, such as life span, abundance, dispersal capacity and diet breadth. However, contrasting trends have been reported for the relationship between body size and these ecological traits. Methods: Fruit-feeding butterflies were used to investigate whether body size is correlated with species abundance, dispersal, permanence, and larval diet breadth in a Neotropical savanna in Brazil (Cerrado). We used Blomberg’s K and Phylogenetic Generalized Least Squares models (PGLS) to measure phylogenetic signal strength in species traits and to estimate size–dispersal–diet breadth associations, while also taking shared ancestry into account. Results: 539 individuals from 27 species were captured, and 190 individuals were recaptured, representing a 35% recapture rate. We found body size to be negatively associated with butterfly abundance, and positively associated with dispersal level, distance traveled, number of traps visited, individual permanence, and diet breadth. These results indicate that larger butterflies are more likely to disperse over longer distances. Moreover, larger butterflies have more generalized larval diets, based on the number of host plant families, genera, and phylogenetic diversity of the host plants they consume as larvae. Smaller butterflies rely on fewer resources, which is reflected in their higher survival in small patches and may explain their lower dispersal ability and higher diet specialization. Nevertheless, lower dispersal ability may, if not compensated by large population sizes, threaten small-bodied species inhabiting environments, such as the Cerrado, which have intense deforestation rates. Conclusions: Body size is positively associated with dispersal and diet breadth for the fruit-feeding butterflies collected in this study.
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- 2021
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50. Experimental control of Tollmien-Schlichting waves using the Wiener-Hopf formalism
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Audiffred, Diego B. S., Cavalieri, André V. G., Brito, Pedro P. C., and Martini, Eduardo
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Physics - Fluid Dynamics - Abstract
Reactive flow control has been shown as a promising tool to improve, among other aspects, the aerodynamic characteristics of an aircraft. This paper focuses on the use of reactive flow control to attenuate Tollmien-Schlichting (TS) waves over a wing profile. TS waves are an instability mechanism that is one of the first stages of boundary layer transition to turbulence. The Wiener-Hopf technique was used in this work for the experimental boundary layer control. The approach improves previous wave-cancellation techniques that, by constructing control kernels in the frequency domain, lead to control kernels with a non-causal part, i.e., actuation would need future sensor information to be constructed. In practical applications, it is unfeasible to access this type of information. Ignoring the non-causal part of the kernel leads to suboptimal solutions that might significantly degrade the performance of the controller. The Wiener-Hopf formalism allows us to take into account causality constraints in the formulation of the control problem, leading to an optimal realistic solution and a control kernel that is causal by construction. Moreover, it is possible to construct the control strategy based only on the power and cross-spectra obtained experimentally, in a data-driven approach. The present work shows how to apply experimentally the Wiener-Hopf resolvent-based formalism using signals from a wind tunnel experiment, demonstrating that the Tollmien-Schlichting waves can be effectively attenuated via a Wiener-Hopf based controller, which yielded better results than a typical wave-cancellation approach., Comment: American Physical Society (APS) copyright
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- 2024
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