2,587 results on '"A C Sousa"'
Search Results
2. Serum Extracellular Vesicles Cargo Approach in Bitches with Mammary Tumors
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Gabriela C. Sousa, Marcos G. Carvalho, Carlos E. Fonseca-Alves, and Fabiana F. Souza
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oncology ,protein ,exosome ,mammary tumor ,liquid biopsy ,Biology (General) ,QH301-705.5 - Abstract
This study investigated serum extracellular vesicles (EVs) in bitches with mammary neoplasms, in order to understand their size, shape, and concentration, as well as their association with tumor malignancy. Thirty bitches were categorized into control (n = 10), mammary tumor grades I and II (GI, n = 13), and grade III (GII, n = 7). Serum was separated from blood collected during mastectomy, and EVs were isolated using size exclusion chromatography. The analysis revealed no significant differences in EV concentrations among groups, with similar concentrations for control, GI, and GII. Ninety-one proteins were identified in EV-enriched samples, with six showing varied abundance across groups. Notably, keratin 18 was highly abundant in GI, while sushi domain-containing protein, EvC ciliary subunit 2, and the joining chain of multimeric IgM and IgA were increased in GII. Additionally, protocadherin 17 and albumin were upregulated in both GI and GII. ROC curves identified potential biomarkers for differentiating tumor grades. Enrichment pathway analysis revealed AFP gene upregulation in the GI. Mass spectrometry proteomics data were deposited in Mendeley Data. The study provides valuable insights into serum EV characterization in bitches, suggesting keratin 18 and protocadherin 17 as potential biomarkers for canine mammary neoplasia, with implications for future diagnostic and therapeutic strategies.
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- 2024
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3. EXISTENCE AND MULTIPLICITY FOR FRACTIONAL DIRICHLET PROBLEM WITH γ ( ξ )-LAPLACIAN EQUATION AND NEHARI MANIFOLD
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da C. Sousa, J. Vanterler, Oliveira, D. S., and Agarwal, Ravi P.
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- 2023
4. Applications of Autonomous Learning Multi Model System to Multiclass Imbalanced Datasets.
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André Seabra, Rodrigo M. M. Ventura, Rui Jorge Almeida, Susana M. Vieira, and João M. C. Sousa
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- 2024
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5. Existence and multiplicity of solutions for fractional differential equations with p-Laplacian at resonance
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Jose Vanterler da C. Sousa, Mariane Pigossi, and Nemat Nyamoradi
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fractional differential equations ,p-laplacian equation ,resonance ,existence and multiplicity ,Mathematics ,QA1-939 - Published
- 2024
6. Whole-plant and leaf determinants of growth rates in progenies of Genipa americana L. (Rubiaceae)
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C. Sousa-Santos, T. M. Lima, A. F. Cerqueira, Â. C. Dalmolin, Á. A. Almeida, M. S. Santos, and M. S. Mielke
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tropical trees ,biomass allocation ,relative growth rate ,carbon balance ,Science ,Biology (General) ,QH301-705.5 ,Zoology ,QL1-991 ,Botany ,QK1-989 - Abstract
Abstract Genipa americana (Rubiaceae) is a fruit tree with broad phytogeographic domain and suitable for different silvicultural systems in the tropics. The knowledge associated with the relative growth rate of species such as G. americana, provides important guidelines for the effective establishment and survival of seedlings after planting in the field. In this study we investigated differences in growth, biomass allocation and photosynthesis of seedlings originating from different mother plants of G. americana in southern Bahia, Brazil. For this, we evaluated fifteen variables associated with carbon balance at the whole plant and leaf scales of twelve G. americana progenies. All seedlings grew over a period of 198 days under similar microclimatic conditions with approximately 65% full sun. Our results showed significant differences in the relative growth rates (RGR), with the highest and lowest mean values being 29.0 and 38.0 mg g-1 day-1, respectively. Differences in RGR between G. americana progenies were highly related to differences in biomass allocation at both whole plant and leaf scales. From a practical point of view, we demonstrate that the selection of mother plants to produce seedlings with higher growth rates, and consequently greater establishment capacity in field plantings, can be made from evaluations of growth and biomass allocation variables at the whole plant scale.
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- 2024
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7. Corrigendum: Reverse left ventricular remodeling after aortic valve replacement for aortic stenosis: a systematic review and meta-analysis
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F. Sousa Nunes, C. Amaral Marques, A. Isabel Pinho, B. Sousa-Pinto, A. Beco, J. Ricardo Silva, F. Saraiva, F. Macedo, A. Leite-Moreira, and C. Sousa
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aortic stenosis ,transcatheter aortic valve implantation (TAVI) ,surgical aortic valve replacement (SAVR) ,reverse left ventricle remodeling ,echocardiography ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Published
- 2024
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8. Reverse left ventricular remodeling after aortic valve replacement for aortic stenosis: a systematic review and meta-analysis
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F. Sousa Nunes, C. Amaral Marques, A. Isabel Pinho, B. Sousa-Pinto, A. Beco, J. Ricardo Silva, F. Saraiva, F. Macedo, A. Leite-Moreira, and C. Sousa
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aortic stenosis ,transcatheter aortic valve implantation (TAVI) ,surgical aortic valve replacement (SAVR) ,reverse left ventricle remodeling ,echocardiography ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Reverse left ventricular (LV) remodeling after aortic valve replacement (AVR), in patients with aortic stenosis, is well-documented as an important prognostic factor. With this systematic review and meta-analysis, we aimed to characterize the response of the unloaded LV after AVR. We searched on MEDLINE/PubMed and Web of Science for studies reporting echocardiographic findings before and at least 1 month after AVR for the treatment of aortic stenosis. In total, 1,836 studies were identified and 1,098 were screened for inclusion. The main factors of interest were structural and dynamic measures of the LV and aortic valve. We performed a random-effects meta-analysis to compute standardized mean differences (SMD) between follow-up and baseline values for each outcome. Twenty-seven studies met the eligibility criteria, yielding 11,751 patients. AVR resulted in reduced mean aortic gradient (SMD: −38.23 mmHg, 95% CI: −39.88 to −36.58, I2=92%), LV mass (SMD: −37.24 g, 95% CI: −49.31 to −25.18, I2=96%), end-diastolic LV diameter (SMD: −1.78 mm, 95% CI: −2.80 to −0.76, I2=96%), end-diastolic LV volume (SMD: −1.6 ml, 95% CI: −6.68 to 3.51, I2=91%), increased effective aortic valve area (SMD: 1.10 cm2, 95% CI: 1.01 to 1.20, I2=98%), and LV ejection fraction (SMD: 2.35%, 95% CI: 1.31 to 3.40%, I2=94.1%). Our results characterize the extent to which reverse remodeling is expected to occur after AVR. Notably, in our study, reverse remodeling was documented as soon as 1 month after AVR.
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- 2024
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9. Human-Centered Trustworthy Framework: A Human-Computer Interaction Perspective.
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Sonia C. Sousa 0001, David Lamas, José Cravino, and Paulo Martins 0001
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- 2024
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10. A Systematic Literature Review of User Trust in AI-Enabled Systems: An HCI Perspective.
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Tita Alissa Bach, Amna Khan, Harry Hallock, Gabriela Beltrão, and Sonia C. Sousa 0001
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- 2024
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11. Fractional tempered differential equations depending on arbitrary kernels
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Ricardo Almeida, Natália Martins, and J. Vanterler da C. Sousa
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fractional differential equations ,tempered fractional derivatives ,existence ,uniqueness ,attractivity ,Mathematics ,QA1-939 - Abstract
In this paper, we expanded the concept of tempered fractional derivatives within both the Riemann-Liouville and Caputo frameworks, introducing a novel class of fractional operators. These operators are characterized by their dependence on a specific arbitrary smooth function. We then investigated the existence and uniqueness of solutions for a particular class of fractional differential equations, subject to specified initial conditions. To aid our analysis, we introduced and demonstrated the application of Picard's iteration method. Additionally, we utilized the Gronwall inequality to explore the stability of the system under examination. Finally, we studied the attractivity of the solutions, establishing the existence of at least one attractive solution for the system. Throughout the paper, we provide examples and remarks to support and reinforce our findings.
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- 2024
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12. Biology of the non-parasitic phase of the cattle tick Rhipicephalus (Boophilus) microplus in an area of Amazon influence
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Daniela P. Sales, Marcelo H. S. Silva-Junior, Caio P. Tavares, Isabella C. Sousa, Dauana M. Sousa, Danilo R. B. Brito, André M. Camargo, Romário Cerqueira Leite, J. L. H. Faccini, Welber D. Z. Lopes, Marcelo B. Labruna, Hermes R. Luz, and Livio M. Costa-Junior
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Rhipicephalus (Boophilus) microplus ,Amazon ,Temperature ,Precipitation ,Biology ,Brazil ,Infectious and parasitic diseases ,RC109-216 - Abstract
Abstract Background Rhipicephalus (Boophilus) microplus is the most important tick species affecting cattle in the world. Under field conditions, the non-parasitic phase of R. (B.) microplus is unknown in the Amazon biome, including Brazil. The present study aimed to evaluate the non-parasitic phase of R. (B.) microplus in field (grass plots) and laboratory conditions. Methods The study was conducted from September 2020 to April 2022 in an Amazonian region (Maranhão State, Brazil). We evaluated the biological parameters of R. (B.) microplus under laboratory and field conditions. Engorged females were exposed to experimental conditions every 14 days, totaling 20 months of study. The following biological parameters were observed: pre-oviposition period, egg mass incubation period, and maximum larval survival period. Results Abiotic data (e.g., temperature and humidity) varied little throughout the year. Precipitation was the factor that varied the most throughout the year (dry ~ 30 mm3 and rain 400 mm3), and the parameters of pre-oviposition and pre-hatching are longer during the rainy season. A possible negative effect of the dry season on the percentage of hatched eggs was observed. Larval longevity in the plots of both control and free females was short (mean ~ 50–60 days), below that recorded for larvae under controlled conditions (mean ~ 95 days). Conclusions Rhipicephalus (Boophilus) microplus was able to complete its non-parasitic phase by producing host-seeking larvae in the pasture during all months of the study. The results indicate that R. (B.) microplus can complete up to six generations per year in biome Amazon. To our knowledge, this is the highest number of annual generations for R. (B.) microplus in Latin America. Graphical Abstract
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- 2024
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13. Osteomyelitis by Microsporum canis and Staphylococcus spp. in cat (Felis catus) – case report
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Fernanda O. Soares, Isabel R. Rosado, Marcus V. C. Sousa, Carolyne F. Dumont, Joely F. F. Bittar, Ian Martin, Marcelo E. Beletti, Roberta T. Melo, and Endrigo G. L. Alves
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Domestic cat ,Mandible ,Microbial sensitivity test ,Osteomyelitis ,Veterinary medicine ,SF600-1100 - Abstract
Abstract Background Staphylococcus spp and Microsporum canis are zoonotic microorganisms which can cause infections and systemic diseases. The bone infection is usually caused by invasion of pathogen through the hematologic route. Mixed osteomyelitis caused by bacteria and fungi is rare, and to date, there have been no reports of mixed osteomyelitis with Staphylococcus spp. and Microsporum canis. Case presentation This essay reports an atypical presentation of mixed osteomyelitis (Staphylococcus spp. and Microsporum canis) in a domestic cat. A 15-month-old female Persian cat was presented to a veterinary service; the main complaint was the appearance of a nodule in the mandibular ventral rostral region. A radiographic exam performed on the animal showed proliferative and osteolytic bone lesions. The patient was submitted to a biopsy for histopathological evaluation, along with bacterial and fungal cultures. Results showed mixed osteomyelitis by Staphylococcus spp. and Microsporum canis. Microbial Sensitivity Test was performed to choose a more suitable treatment. Two surgical procedures were executed to resect and curette the lesion, and treatments with anti-inflammatory, antibiotic, and antifungal drugs were established, showing a positive clinical evolution. After 8 months of treatment, the patient’s owner moved to a different city, and the animal was seen by other veterinarians, who followed along with the same treatment. However, due to complications and a diminishing quality of life over 4 years of diagnosis, the patient was euthanized. Conclusion Given the above, mixed osteomyelitis is difficult to treat and can cause losses of life quality resulting death, especially in infections where M. canis is the agent causing the disease. Bacterial osteomyelitis is more frequently reported. But the lack of investigation of microorganisms other than bacteria, such as fungal cases, may imply in underdiagnosed cases. Treatment of osteomyelitis can be difficult considering the difficulties in isolating the pathological agent, resistance to the drug used, prolonged treatment time, and cost.
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- 2024
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14. Preparation of N-heterylarenes from the perspective of phenylhydrazine-based under the principles green chemistry
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Guillermo Penieres-Carrillo, Ricardo Alfredo Luna-Mora, Francisco Barrera-Téllez, Alejandro Martínez-Záldivar, Alicia Hernández-Campos, Rafael Castillo-Bocanegra, Ana M. R. C. Sousa, and Hulme Ríos-Guerra
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Chemistry ,QD1-999 - Abstract
Herein, modern green synthesis approaches are studied to assemble N-heterylarenes scaffolds via a non-catalyzed intramolecular 5/6-exo-dig cyclocondensation reaction based on the in-situ generation of arenehydrazonopentan-/hexan-2-one. Accordingly, the formation of two N-heteryl moieties, pyrazol-1-yl and pyridazin-1(4H)-yl, was initially studied. Therefore, appropriate fluorophenyl was first converted into their respective phenylhydrazine by SNAr reaction and then reacted with different trigonal carbonyl bielectrophiles (-CO-, -CO2R, and -CO2H) in ethanol in the presence of US, MW, IR, and an IR· US irradiation mixture. Cyclic nitrogenous cores were best obtained when subjected to microwave irradiation with ketone and arylhydrazine as starting reagents, allowing them to get excellent yields quickly. Arylhydrazine reactants featuring Π-donor groups underwent the best 5/6-exo-dig type annulment reaction. Presumably, the observed improvements in EDG-dependent reaction efficiency reflect changes in the nucleophilicity of arylhydrazines intermediates as α-nucleophilic reactants.
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- 2024
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15. Case report: Equine metacarpophalangeal joint partial and full thickness defects treated with allogenic equine synovial membrane mesenchymal stem/stromal cell combined with umbilical cord mesenchymal stem/stromal cell conditioned medium
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I. L. Reis, B. Lopes, P. Sousa, A. C. Sousa, A. Rêma, A. R. Caseiro, I. Briote, A. M. Rocha, J. P. Pereira, C. M. Mendonça, J. M. Santos, L. Lamas, L. M. Atayde, R. D. Alvites, and A. C. Maurício
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case report ,equine ,osteochondral defect ,synovial membrane mesenchymal stromal/stem cell ,umbilical cord conditioned medium ,cell-based medicinal product ,Veterinary medicine ,SF600-1100 - Abstract
Here, we describe a case of a 5-year-old show-jumping stallion presented with severe lameness, swelling, and pain on palpation of the left metacarpophalangeal joint (MCj). Diagnostic imaging revealed full and partial-thickness articular defects over the lateral condyle of the third metacarpus (MC3) and the dorsolateral aspect of the first phalanx (P1). After the lesion’s arthroscopic curettage, the patient was subjected to an innovative regenerative treatment consisting of two intra-articular injections of equine synovial membrane mesenchymal stem/stromal cells (eSM-MSCs) combined with umbilical cord mesenchymal stem/stromal cells conditioned medium (UC-MSC CM), 15 days apart. A 12-week rehabilitation program was accomplished, and lameness, pain, and joint effusion were remarkably reduced; however, magnetic resonance imaging (MRI) and computed tomography (CT) scan presented incomplete healing of the MC3’s lesion, prompting a second round of treatment. Subsequently, the horse achieved clinical soundness and returned to a higher level of athletic performance, and imaging exams revealed the absence of lesions at P1, fulfillment of the osteochondral lesion, and cartilage-like tissue formation at MC3’s lesion site. The positive outcomes suggest the effectiveness of this combination for treating full and partial cartilage defects in horses. Multipotent mesenchymal stem/stromal cells (MSCs) and their bioactive factors compose a novel therapeutic approach for tissue regeneration and organ function restoration with anti-inflammatory and pro-regenerative impact through paracrine mechanisms.
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- 2024
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16. Biomechanical gait analysis in sheep: kinematic parameters
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Bruna Silva, Filipa João, Sandra Amado, Rui D. Alvites, Ana C. Maurício, Bárbara Esteves, Ana C. Sousa, Bruna Lopes, Patrícia Sousa, Juliana R. Dias, António Veloso, Paula Pascoal-Faria, and Nuno Alves
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sheep model ,gait analysis ,3D kinematic ,spatio-temporal parameters ,joint angular displacement ,biomechanics ,Biotechnology ,TP248.13-248.65 - Abstract
Animals have been used as models to help to better understand biological and anatomical systems, and pathologies in both humans and non-human species, and sheep are often used as an in vivo experimental model for orthopedic research. Gait analysis has been shown to be an important tool in biomechanics research with clinical applications. The purpose of this study was to perform a kinematic analysis using a tridimensional (3D) reconstruction of the sheep hindlimb. Seven healthy sheep were evaluated for natural overground walking, and motion capture of the right hindlimb was collected with an optoelectronic system while the animals walked in a track. The analysis addressed gait spatiotemporal variables, hip, knee and ankle angle and intralimb joint angle coordination measures during the entire walking cycle. This study is the first that describes the spatiotemporal parameters from the hip, knee and ankle joints in a tridimensional way: flexion/extension; abduction/adduction and inter/external rotation. The results of this assessment can be used as an outcome indicator to guide treatment and the efficacy of different therapies for orthopedic and neurological conditions involving the locomotor system of the sheep animal model.
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- 2024
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17. Mesophotic Hardground Revealed by Multidisciplinary Cruise on the Brazilian Equatorial Margin
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Luigi Jovane, Allana Q. Azevedo, Eduardo H. Marcon, Fernando Collo Correa e Castro, Halesio Milton C. de Barros Neto, Guarani de Hollanda Cavalcanti, Fabíola A. Lima, Linda G. Waters, Camila F. da Silva, André C. Souza, Lucy Gomes Sant’Anna, Thayse Sant’Ana Fonseca, Luis Silva, Marco A. de C. Merschmann, Gilberto P. Dias, Prabodha Das, Celio Roberto Jonck, Rebeca G. M. Lizárraga, Diana C. de Freitas, Maria R. dos Santos, Kerly A. Jardim, Izabela C. Laurentino, Kyssia K. C. Sousa, Marilia C. Pereira, Yasmim da S. Alencar, Nathalia M. L. Costa, Tobias Rafael M. Coelho, Kevin L. C. Ferrer do Carmo, Rebeca C. Melo, Iara Gadioli Santos, Lucas G. Martins, Sabrina P. Ramos, Márcio R. S. dos Santos, Matheus M. de Almeida, Vivian Helena Pellizari, and Paulo Y. G. Sumida
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Amapá continental shelf ,multidisciplinary cruise ,Great Amazon Reef System ,Amazon River plume ,Mineralogy ,QE351-399.2 - Abstract
The Amapá margin, part of the Brazilian Equatorial Margin (BEM), is a key region that plays a strategic role in the global climate balance between the North and South Atlantic Ocean as it is strictly tied to equatorial heat conveyance and the fresh/salt water equilibrium with the Amazon River. We performed a new scientific expedition on the Amapá continental shelf (ACS, northern part of the Amazon continental platform) collecting sediment and using instrumental observation at an unstudied site. We show here the preliminary outcomes following the applied methodologies for investigation. Geophysical, geological, and biological surveys were carried out within the ACS to (1) perform bathymetric and sonographic mapping, high-resolution sub-surface geophysical characterization of the deep environment of the margin of the continental platform, (2) characterize the habitats and benthic communities through underwater images and biological sampling, (3) collect benthic organisms for ecological and taxonomic studies, (4) define the mineralogical and (5) elemental components of sediments from the study region, and (6) identify their provenance. The geophysical data collection included the use of bathymetry, a sub-bottom profiler, side scan sonar, bathythermograph acquisition, moving vessel profiler, and a thermosalinograph. The geological data were obtained through mineralogical, elemental, and grain size analysis. The biological investigation involved epifauna/infauna characterization, microbial analysis, and eDNA analysis. The preliminary results of the geophysical mapping, shallow seismic, and ultrasonographic surveys endorsed the identification of a hard substrate in a mesophotic environment. The preliminary geological data allowed the identification of amphibole, feldspar, biotite, as well as other minerals (e.g., calcite, quartz, goethite, ilmenite) present in the substrata of the Amapá continental shelf. Silicon, iron, calcium, and aluminum composes ~85% of sediments from the ACS. Sand and clay are the main fraction from these sediments. Within the sediments, Polychaeta (Annelida) dominated, followed by Crustacea (Arthropoda), and Ophiuroidea (Echinodermata). Through TowCam videos, 35 taxons with diverse epifauna were recorded, including polychaetes, hydroids, algae, gastropods, anemones, cephalopods, crustaceans, fishes, and sea stars.
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- 2024
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18. Obtention and Characterization of Microcrystalline Cellulose from Industrial Melon Residues Following a Biorefinery Approach
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Ricardo Gómez-García, Sérgio C. Sousa, Óscar L. Ramos, Débora A. Campos, Cristóbal N. Aguilar, Ana R. Madureira, and Manuela Pintado
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biopolymer ,circular bioeconomy ,crystalline cellulose ,food-waste biorefinery ,melon residues ,X-ray diffraction ,Organic chemistry ,QD241-441 - Abstract
Residual melon by-products were explored for the first time as a bioresource of microcrystalline cellulose (MCC) obtention. Two alkaline extraction methods were employed, the traditional (4.5% NaOH, 2 h, 80 °C) and a thermo-alkaline in the autoclave (2% NaOH, 1 h, 100 °C), obtaining a yield of MCC ranging from 4.76 to 9.15% and 2.32 to 3.29%, respectively. The final MCCs were characterized for their chemical groups by Fourier-transform infrared spectroscopy (FTIR), crystallinity with X-ray diffraction, and morphology analyzed by scanning electron microscope (SEM). FTIR spectra showed that the traditional protocol allows for a more effective hemicellulose and lignin removal from the melon residues than the thermo-alkaline process. The degree of crystallinity of MCC ranged from 51.51 to 61.94% and 54.80 to 55.07% for the thermo-alkaline and traditional processes, respectively. The peaks detected in X-ray diffraction patterns indicated the presence of Type I cellulose. SEM analysis revealed microcrystals with rough surfaces and great porosity, which could remark their high-water absorption capacity and drug-carrier capacities. Thus, these findings could respond to the need to valorize industrial melon by-products as raw materials for MCC obtention with potential applications as biodegradable materials.
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- 2024
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19. Analysis of a Simple Method to Change the Wettability of the PDMS Surface for Biomicrofluidic Applications.
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Inês M. Gonçalves, Diana Pinho, Andrea Zille, Hirokazu Kaji, Graça Minas, Rui A. Lima, Patrícia C. Sousa, and Ana S. Moita
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- 2023
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20. Heuristics to Design Trustworthy Technologies: Study Design and Current Progress.
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Iuliia Paramonova, Sonia C. Sousa 0001, and David Lamas
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- 2023
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21. Towards Cross-Cultural Assessment of Trust in High-Risk AI.
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Gabriela Beltrão, Sonia C. Sousa 0001, and David Lamas
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- 2023
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22. Trust in Facial Recognition Systems: A Perspective from the Users.
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Gabriela Beltrão, Sonia C. Sousa 0001, and David Lamas
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- 2023
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23. Unmasking Trust: Examining Users' Perspectives of Facial Recognition Systems in Mozambique.
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Gabriela Beltrão, Sonia C. Sousa 0001, and David Lamas
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- 2023
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24. Exploring Factors Affecting User Perception of Trustworthiness in Advanced Technology: Preliminary Results.
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Iuliia Paramonova, Sonia C. Sousa 0001, and David Lamas
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- 2023
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25. The Use of Semantic Knowledge in Task Planning for Robotic Agents, Minimising Human Error.
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Rodrigo Bernardo, João M. C. Sousa, and Paulo J. S. Gonçalves
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- 2023
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26. poolHelper: An R package to help in designing Pool‐Seq studies
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João Carvalho, Rui Faria, Roger K. Butlin, and Vitor C. Sousa
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experimental design ,open source ,Pool‐seq ,R package ,simulations ,Ecology ,QH540-549.5 ,Evolution ,QH359-425 - Abstract
Abstract Next‐generation sequencing of pooled samples (Pool‐seq) is an important tool in population genomics and molecular ecology. In Pool‐seq, the relative number of reads with an allele reflects the allele frequencies in the sample. However, unequal individual contributions to the pool and sequencing errors can lead to inaccurate allele frequency estimates, influencing downstream analysis. When designing Pool‐seq studies, researchers need to decide the pool size (number of individuals) and average depth of coverage (sequencing effort). An efficient sampling design should maximise the accuracy of allele frequency estimates while minimising the sequencing effort. We describe a novel tool to simulate single nucleotide polymorphism (SNP) data using coalescent theory and account for sources of uncertainty in Pool‐seq. We introduce an R package, poolHelper, enabling users to simulate Pool‐seq data under different combinations of average depth of coverage and pool size, accounting for unequal individual contributions and sequencing errors, modelled by adjustable parameters. The mean absolute error is computed by comparing the sample allele frequencies obtained based on individual genotypes with the frequency estimates obtained with Pool‐seq. poolHelper enables users to simulate multiple combinations of pooling errors, average depth of coverage, pool sizes and number of pools to assess how they influence the error of sample allele frequencies and expected heterozygosity. Using simulations under a single population model, we illustrate that increasing the depth of coverage does not necessarily lead to more accurate estimates, reinforcing that finding the best Pool‐seq study design is not straightforward. Moreover, we show that simulations can be used to identify different combinations of parameters with similarly low mean absolute errors. This can help users to define an effective sampling design by using those combinations of parameters that minimise the sequencing effort. The poolHelper package provides tools for performing simulations with different combinations of parameters (e.g. pool size, depth of coverage, unequal individual contribution) before sampling and generating data, allowing users to define sampling schemes based on simulations. This allows researchers to focus on the best sampling scheme to answer their research questions. poolHelper is comprehensively documented with examples to guide effective use.
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- 2023
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27. In-plane reorientation induced single laser pulse magnetization reversal
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Y. Peng, D. Salomoni, G. Malinowski, W. Zhang, J. Hohlfeld, L. D. Buda-Prejbeanu, J. Gorchon, M. Vergès, J. X. Lin, D. Lacour, R. C. Sousa, I. L. Prejbeanu, S. Mangin, and M. Hehn
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Science - Abstract
Abstract Single Pulse All Optical Switching represents the ability to reverse the magnetization of a nanostructure using a femtosecond single laser pulse without any applied field. Since the first switching experiments carried out on GdFeCo ferrimagnets, this phenomena has been only recently extended to a few other materials, MnRuGa alloys and Tb/Co multilayers with a very specific range of thickness and composition. Here, we demonstrate that single pulse switching can be obtained for a large range of rare earth–transition metal multilayers, making this phenomenon much more general. Surprisingly, the threshold fluence for switching is observed to be independent of the laser pulse duration. Moreover, at high laser intensities, concentric ring domain structures are induced. These striking features contrast to those observed in Gd based materials pointing towards a different reversal mechanism. Concomitant with the demonstration of an in-plane magnetization reorientation, a precessional reversal mechanism explains all the observed features.
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- 2023
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28. A Comparative Study of Different Milling Strategies on Productivity, Tool Wear, Surface Roughness, and Vibration
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Francisco J. G. Silva, Rui P. Martinho, Luís L. Magalhães, Filipe Fernandes, Rita C. M. Sales-Contini, Luís M. Durão, Rafaela C. B. Casais, and Vitor F. C. Sousa
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plunge milling ,conventional milling ,machining strategy ,tool wear ,cycle time ,productivity ,Production capacity. Manufacturing capacity ,T58.7-58.8 - Abstract
Strategies for obtaining deep slots in soft materials can vary significantly. Conventionally, the tool travels along the slot, removing material mainly with the side cutting edges. However, a “plunge milling” strategy is also possible, performing the cut vertically, taking advantage of the tip cutting edges that almost reach the center of the tool. Although both strategies are already commonly used, there is a clear gap in the literature in studies that compare tool wear, surface roughness, and productivity in each case. This paper describes an experimental study comparing the milling of deep slots in AA7050-T7451 aluminum alloy, coated with a novel DLCSiO500W3.5O2 layer to minimize the aluminum adhesion to the tool, using conventional and plunge milling strategies. The main novelty of this paper is to present a broad study regarding different factors involved in machining operations and comparing two distinct strategies using a novel tool coating in the milling of aeronautical aluminum alloy. Tool wear is correlated with the vibrations of the tools in each situation, the cycle time is compared between the cases studied, and the surface roughness of the machined surfaces is analyzed. This study concludes that the cycle time of plunge milling can be about 20% less than that of conventional milling procedures, favoring economic sustainability and modifying the wear observed on the tools. Plunge milling can increase productivity, does not increase tool tip wear, and avoids damaging the side edges of the tool, which can eventually be used for final finishing operations. Therefore, it can be said that the plunge milling strategy improves economic and environmental sustainability as it uses all the cutting edges of the tools in a more balanced way, with less global wear.
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- 2024
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29. Short-Term Forecast of Photovoltaic Solar Energy Production Using LSTM
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Filipe D. Campos, Tiago C. Sousa, and Ramiro S. Barbosa
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short-term forecasting ,LSTM ,solar energy production ,ANN ,CNN ,Technology - Abstract
In recent times, renewable energy sources have gained considerable vitality due to their inexhaustible resources and the detrimental effects of fossil fuels, such as the impact of greenhouse gases on the planet. This article aims to be a supportive tool for the development of research in the field of artificial intelligence (AI), as it presents a solution for predicting photovoltaic energy production. The basis of the AI models is provided from two data sets, one for generated electrical power and another for meteorological data, related to the year 2017, which are freely available on the Energias de Portugal (EDP) Open Project website. The implemented AI models rely on long short-term memory (LSTM) neural networks, providing a forecast value for electrical energy with a 60-min horizon based on meteorological variables. The performance of the models is evaluated using the performance indicators MAE, RMSE, and R2, for which favorable results were obtained, with particular emphasis on forecasts for the spring and summer seasons.
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- 2024
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30. Fuzzy Multi-Item Newsvendor Problem: An Application to Inventory Management
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João M. C. Sousa, Rodrigo Luís, Rui Mirra Santos, Luís Mendonça, and Susana M. Vieira
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multi-item newsvendor problem ,fuzzy newsvendor problem ,inventory management ,genetic algorithms ,credibility estimation ,Mathematics ,QA1-939 - Abstract
This paper proposes a novel approach to the fuzzy newsvendor problem for inventory management applications. The main contributions of the paper are the following: a new credibility estimation is proposed, to explore the neighborhood around the most impactful demand scenarios; a simulation procedure was designed for the different demand scenarios, which allows comparison of the proposed approach with classical and fuzzy multi-item newsvendor problems; a modified genetic algorithm (GA) is introduced to ameliorate previous genetic algorithms in both the generation and evaluation of solutions. The new formulation of the fuzzy newsvendor problem, together with the modified GA, were shown to improve the average profit by up to 55% in problems with low-budget scenarios.
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- 2024
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31. Equine Musculoskeletal Pathologies: Clinical Approaches and Therapeutical Perspectives—A Review
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Inês L. Reis, Bruna Lopes, Patrícia Sousa, Ana C. Sousa, Ana R. Caseiro, Carla M. Mendonça, Jorge M. Santos, Luís M. Atayde, Rui D. Alvites, and Ana C. Maurício
- Subjects
conservative therapies ,equine ,hemoderivatives ,musculoskeletal ,osteoarthritis ,physiotherapy ,Veterinary medicine ,SF600-1100 - Abstract
Musculoskeletal injuries such as equine osteoarthritis, osteoarticular defects, tendonitis/desmitis, and muscular disorders are prevalent among sport horses, with a fair prognosis for returning to exercise or previous performance levels. The field of equine medicine has witnessed rapid and fruitful development, resulting in a diverse range of therapeutic options for musculoskeletal problems. Staying abreast of these advancements can be challenging, prompting the need for a comprehensive review of commonly used and recent treatments. The aim is to compile current therapeutic options for managing these injuries, spanning from simple to complex physiotherapy techniques, conservative treatments including steroidal and non-steroidal anti-inflammatory drugs, hyaluronic acid, polysulfated glycosaminoglycans, pentosan polysulfate, and polyacrylamides, to promising regenerative therapies such as hemoderivatives and stem cell-based therapies. Each therapeutic modality is scrutinized for its benefits, limitations, and potential synergistic actions to facilitate their most effective application for the intended healing/regeneration of the injured tissue/organ and subsequent patient recovery. While stem cell-based therapies have emerged as particularly promising for equine musculoskeletal injuries, a multidisciplinary approach is underscored throughout the discussion, emphasizing the importance of considering various therapeutic modalities in tandem.
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- 2024
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32. Low‐energy amplitude‐modulated electromagnetic field exposure: Feasibility study in patients with hepatocellular carcinoma
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Fernanda Capareli, Frederico Costa, Jack A. Tuszynski, Micelange C. Sousa, Yone de C. Setogute, Pablo D. Lima, Luciana Carvalho, Elizabeth Santos, Brenda P. Gumz, Jorge Sabbaga, Tiago B. deCastria, Denis L. Jardim, Daniela Freitas, Natally Horvat, Regis O. F. Bezerra, Leonardo Testagrossa, Tiago Costa, Tatiana Zanesco, Antonio F. Iemma, and Ghassan K. Abou‐Alfa
- Subjects
EMF ,hemodynamics ,hepatocellular carcinoma ,low‐frequency electromagnetic fields ,safety ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Abstract Background Patients with advanced hepatocellular carcinoma (HCC) and poor liver function lack effective systemic therapies. Low‐energy electromagnetic fields (EMFs) can influence cell biological processes via non‐thermal effects and may represent a new treatment option. Methods This single‐site feasibility trial enrolled patients with advanced HCC, Child‐Pugh A and B, Eastern Cooperative Oncology Group 0–2. Patients underwent 90‐min amplitude‐modulated EMF exposure procedures every 2–4 weeks, using the AutEMdev (Autem Therapeutics). Patients could also receive standard care. The primary endpoints were safety and the identification of hemodynamic variability patterns. Exploratory endpoints included health‐related quality of life (HRQoL), overall survival (OS). and objective response rate (ORR) using RECIST v1.1. Results Sixty‐six patients with advanced HCC received 539 AutEMdev procedures (median follow‐up, 30 months). No serious adverse events occurred during procedures. Self‐limiting grade 1 somnolence occurred in 78.7% of patients. Hemodynamic variability during EMF exposure was associated with specific amplitude‐modulation frequencies. HRQoL was maintained or improved among patients remaining on treatment. Median OS was 11.3 months (95% confidence interval [CI]: 6.0, 16.6) overall (16.0 months [95% CI: 4.4, 27.6] and 12.0 months [6.4, 17.6] for combination therapy and monotherapy, respectively). ORR was 24.3% (32% and 17% for combination therapy and monotherapy, respectively). Conclusion AutEMdev EMF exposure has an excellent safety profile in patients with advanced HCC. Hemodynamic alterations at personalized frequencies may represent a surrogate of anti‐tumor efficacy. NCT01686412.
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- 2023
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33. Solutions for a nonhomogeneous p&q-Laplacian problem via variational methods and sub-supersolution technique
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Leandro S. Tavares and J. Vanterler C. Sousa
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\(p\&q\)-laplacian operator ,nonhomogeneous operator ,sub-supersolutions ,existence ,multiplicity ,Applied mathematics. Quantitative methods ,T57-57.97 - Abstract
In this paper it is obtained, through variational methods and sub-supersolution arguments, existence and multiplicity of solutions for a nonhomogeneous problem which arise in several branches of science such as chemical reactions, biophysics and plasma physics. Under a general hypothesis it is proved an existence result and multiple solutions are obtained by considering an additional natural condition.
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- 2023
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34. Toward an Instrumented Strength Microprobe – Origins of the Oliver-Pharr Method and Continued Advancements in Nanoindentation: Part 1
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C. Sousa, Bryer, primary, Hay, Jennifer, additional, and L. Cote, Danielle, additional
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- 2023
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35. Toward an Instrumented Strength Microprobe – Origins of the Oliver-Pharr Method and Continued Advancements in Nanoindentation: Part 2
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C. Sousa, Bryer, primary, Hay, Jennifer, additional, and L. Cote, Danielle, additional
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- 2023
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36. Exigências mentais e prosperidade dos trabalhadores mais velhos: O papel da capacidade para o trabalho
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Inês C. Sousa and Daniela Baltazar
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exigências mentais ,capacidade para o trabalho ,prosperidade no trabalho ,trabalhadores mais velhos ,envelhecimento ,Business ,HF5001-6182 - Abstract
O envelhecimento da população ativa e as crescentes exigências mentais no trabalho representam um desafio para a sustentabilidade da vida profissional e para a competitividade das organizações. A investigação tem-se debruçado sobre a prosperidade no trabalho como um proxy da sustentabilidade de carreira, particularmente na sua fase final. No entanto, pouco ainda se sabe sobre os mecanismos subjacentes às relações entre prosperidade e seus antecedentes. O objetivo deste estudo é examinar o papel mediador da capacidade para o trabalho na relação entre as exigências mentais do trabalho e a prosperidade no grupo dos trabalhadores mais velhos. Uma amostra de 163 trabalhadores respondeu a um questionário on-line. Os resultados suportam a hipótese de mediação, mas o efeito direto das exigências mentais na prosperidade não foi significativo, o que enfatiza a importância da capacidade para o trabalho. As implicações teóricas e práticas são discutidas.
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- 2023
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37. Applying genomic approaches to delineate conservation strategies using the freshwater mussel Margaritifera margaritifera in the Iberian Peninsula as a model
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S. Perea, S. L. Mendes, C. Sousa-Santos, P. Ondina, R. Amaro, J. Castro, E. San-Miguel, C. S. Lima, M. Garcia, V. Velasquez, P. Garcia-Roves, D. Fernández, R. Araujo, V. C. Sousa, and J. Reis
- Subjects
Medicine ,Science - Abstract
Abstract Effective conservation actions to counteract the current decline of populations and species require a deep knowledge on their genetic structure. We used Single Nucleotide Polymorphisms (SNPs) to infer the population structure of the highly threatened freshwater pearl mussel Margaritifera margaritifera in the Iberian Peninsula. A total of 130 individuals were collected from 26 locations belonging to 16 basins. We obtained 31,692 SNPs through Genotyping by Sequencing (GBS) and used this dataset to infer population structure. Genetic diversity given as observed heterozygosity was low. Pairwise FST comparisons revealed low levels of genetic differentiation among geographically close populations. Up to 3 major genetic lineages were determined: Atlantic, Cantabrian and Douro. This structure suggests a close co-evolutionary process with brown trout (Salmo trutta), the primordial fish host of this mussel in the studied area. Some sub-basins showed some genetic structuring, whereas in others no intrapopulation differentiation was found. Our results confirm that genetic conservation units do not match individual basins, and that knowledge about the genetic structure is necessary before planning recovery plans that may involve relocation or restocking. The same reasoning should be applied to strictly freshwater species that are sessile or have restricted dispersal abilities and are currently imperiled worldwide.
- Published
- 2022
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38. Minimizing total completion time in large-sized pharmaceutical quality control scheduling.
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Miguel S. E. Martins, Joaquim L. Viegas, Tiago Coito, Bernardo M. Firme, Andrea Costigliola, João Figueiredo, Susana M. Vieira, and João M. C. Sousa
- Published
- 2023
- Full Text
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39. Optical Distribution Network Design Using PSO.
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Antônio L. S. Aguiar, Francisco B. C. Sousa, and Yuri V. L. de Melo
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- 2023
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40. On a class of capillarity phenomenon with logarithmic nonlinearity involving θ (· )-Laplacian operator.
- Author
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Arhrrabi elhoussain, El-Houari Hamza, and J. Vanterler da C. Sousa
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- 2024
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41. Multiple-Instance Regression for Metal Powder Hall Flow Rate Prediction Using Augmented Particle Size and Shape Data
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Ashley Schuliger, Stephen Price, Bryer C. Sousa, Danielle L. Cote, and Rodica Neamtu
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powder flowability ,Hall flow ,cold spray ,metal additive manufacturing ,powder ,Chemistry ,QD1-999 - Abstract
This study investigates the relationship between metallic powders and their flowability behavior (captured in terms of Hall flow rates using Hall flowmeters). Due to the many trait dependencies of powder flowability, which have made the formulation of a physical and mechanistic generalizable model difficult to resolve, this study seeks to develop an alternative data-driven framework based on powder size and shape characteristics for Hall-flow-rate predictions. A multiple-instance regression framework was both developed for processing multiple-instance powder data and compared with standard machine learning models. Data augmentation was found to improve the overall performance of the framework, although the limited dataset was a constraint. Still, the study contributes to ongoing efforts to identify traditional, associative, and generalizable patterns between powder properties and resultant flowability behaviors. The findings show promise for real-world applications with a larger dataset, such that this initial application of multiple instance regression frameworks for metal powder Hall-flow-rate predictions as a function of powder particle size and shape data can be scrutinized in full.
- Published
- 2023
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42. Microstructural, Corrosion, and Mechanical Characterization of Friction Stir Welded Al 6022-to-ZEK100 Mg Joints
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Qingli Ding, Hrishikesh Das, Piyush Upadhyay, Bryer C. Sousa, Kubra Karayagiz, Adam Powell, and Brajendra Mishra
- Subjects
friction stir weld ,corrosion ,intermetallic ,electrochemical testing ,microindentation ,lap-shear strength ,Chemical technology ,TP1-1185 - Abstract
Friction stir welded (FSW) aluminum–magnesium lightweight vehicle joints have gained significant interest due to their high strength-to-weight ratio. In this work, the corrosion resistance of this material is analyzed through electrochemical tests, which include open circuit potential (OCP) inspection and potentiodynamic polarization (PD) scanning. Weight loss measurements tested the corrosion rate of the FSW weld through cyclic corrosion testing (CCT) according to the standard SAEJ 2334. Mechanical properties were also investigated, including lap-shear strength, micro- and nano-hardness mapping, and true stress–strain curves as a function of local processing history. The electrochemical results indicate that the center weld zone’s corrosion property stays between the two base alloys. Indentation-based testing demonstrated that the weld zone behaves differently from base alloys. Lap shear strength surprisingly did not drop much even after eight weeks of cyclic corrosion tests, indicating that the joint did not allow any ingress of the electrolyte.
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- 2023
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43. Cu(In,Ga)Se2 based ultrathin solar cells the pathway from lab rigid to large scale flexible technology
- Author
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T. S. Lopes, J. P. Teixeira, M. A. Curado, B. R. Ferreira, A. J. N. Oliveira, J. M. V. Cunha, M. Monteiro, A. Violas, J. R. S. Barbosa, P. C. Sousa, I. Çaha, J. Borme, K. Oliveira, J. Ring, W. C. Chen, Y. Zhou, K. Takei, E. Niemi, F. L. Deepak, M. Edoff, G. Brammertz, P. A. Fernandes, B. Vermang, and P. M. P. Salomé
- Subjects
Electronics ,TK7800-8360 ,Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
Abstract The incorporation of interface passivation structures in ultrathin Cu(In,Ga)Se2 based solar cells is shown. The fabrication used an industry scalable lithography technique—nanoimprint lithography (NIL)—for a 15 × 15 cm2 dielectric layer patterning. Devices with a NIL nanopatterned dielectric layer are benchmarked against electron-beam lithography (EBL) patterning, using rigid substrates. The NIL patterned device shows similar performance to the EBL patterned device.The impact of the lithographic processes in the rigid solar cells’ performance were evaluated via X-ray Photoelectron Spectroscopy and through a Solar Cell Capacitance Simulator. The device on stainless-steel showed a slightly lower performance than the rigid approach, due to additional challenges of processing steel substrates, even though scanning transmission electron microscopy did not show clear evidence of impurity diffusion. Notwithstanding, time-resolved photoluminescence results strongly suggested elemental diffusion from the flexible substrate. Nevertheless, bending tests on the stainless-steel device demonstrated the mechanical stability of the CIGS-based device.
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- 2023
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44. A PEDAGOGIA DA ALTERNÂNCIA E A FORMAÇÃO DOS INTELECTUAIS DO CAMPO (CAMPONESES) NO BRASIL
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CONCEIÇÃO SILVA ARAUJO, JOSÉ, primary and JULIANA C SOUSA, MARIA, additional
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- 2023
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45. Conservation Challenges Imposed by Evolutionary History and Habitat Suitability Shifts of Endangered Freshwater Mussels under a Global Climate Change Scenario
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Joaquim Reis, Silvia Perea, Mafalda Gama, Sofia L. Mendes, Vitor C. Sousa, Cristina Lima, Filipe Banha, Maria Gil, Maria Garcia Alvarez, Pedro Anastácio, Carla Sousa Santos, and Rafael Araujo
- Subjects
genetic population structure ,Mediterranean-type temporary stream ,drought ,distribution modeling ,rescue ,Iberia ,Biology (General) ,QH301-705.5 - Abstract
Climate change and associated shifts in temperature and precipitation patterns have become an increasing concern as drivers of ongoing biodiversity loss. The Mediterranean region is particularly vulnerable, being both a biodiversity hotspot and a region very prone to desertification. Freshwater mussels are amongst the most threatened invertebrate taxa worldwide. Unio tumidiformis is an endemic and endangered species restricted to the southern Iberian Peninsula, living in temporary Mediterranean-type streams. Freshwater mussels need a fish host for successful larval transformation, meaning U. tumidiformis must belong to the genus Squalius. The main objective of this study was to evaluate the vulnerability of U. tumidiformis to climate change, by studying its population genetics and evolutionary history, its current and future habitat suitability, and that of its hosts. Genetic population structure and diversity were assessed using Single-Nucleotide Polymorphisms through Genotyping by Sequencing and used to infer species evolutionary history. The species potential distribution was modeled using an ensemble forecasting approach, and future shifts in habitat suitability were assessed with the projected climate data layers from Worldclim. Most populations showed extreme genetic differentiation (Fst up to 0.745), even from close neighboring ones. Upper Guadiana populations were more diverse and less differentiated. We hypothesize that U. tumidiformis originated in Upper Guadiana and followed the same colonization routes as their hosts with numerous founder effects and bottlenecks. Our results also predicted a reduction of 99% of climatically suitable areas for U. tumidiformis in the Iberian Peninsula until 2040. For the fish hosts, a maximum 42% reduction in suitable areas was estimated throughout the century, with remaining adequate habitats in the north. Our results suggest that difficult conservation options are necessary, prioritizing the preservation of populations, translocations to the northern area of its historical range and stream engineering to increase resilience to droughts.
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- 2024
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46. Silica Microparticles from Sugarcane By-Products as an Encapsulation System for Retinoids Aimed at Topical Sustained Release
- Author
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Joana R. Costa, Ana Helena Costa, João Azevedo-Silva, Diana Tavares-Valente, Sérgio C. Sousa, Tânia Neto, Manuela E. Pintado, and Ana Raquel Madureira
- Subjects
retinol ,silica microparticles ,response surface methodology ,control release ,topical delivery ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
The encapsulation of retinol within silica microparticles has emerged as a promising opportunity in the realm of cosmetic and pharmaceutical formulations, driven by the need to reinforce the photoprotection and oxidation stability of retinol. This work examines the process of encapsulating retinol into silica microparticles. The association efficiency, microparticle size, molecular structure, morphology, oxidation, and release profile, as well as biocompatibility and skin sensitization, were evaluated. Results showed that 0.03% of retinol and 9% of emulsifier leads to an association efficiency higher than 99% and a particle size with an average of 5.2 µm. FTIR results indicate that there is an association of retinol with the silica microparticles, and some may be on the surface. Microscopy indicates that when association happens, there is less aggregation of the particles. Oxidation occurs in two different phases, the first related to the retinol on the surface and the second to the associated retinol. In addition, a burst release of up to 3 h (30% free retinol, 17% associated retinol) was observed, as well as a sustained release of 44% of retinol up to 24 h. Encapsulation allowed an increase in the minimal skin cytotoxic concentrations of retinol from 0.04 μg/mL to 1.25 mg/mL without skin sensitization. Overall, retinol is protected when associated with silica microparticles, being safe to use in cosmetics and dermatology.
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- 2024
- Full Text
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47. Comparative Evaluation of Titanium Feedstock Powder Derived from Recycled Battlefield Scrap vs. Virgin Powder for Cold Spray Processing
- Author
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Kiran G. Judd, Kyle Tsaknopoulos, Bryer C. Sousa, Marc Pepi, and Danielle L. Cote
- Subjects
gas atomization ,titanium ,recycled feedstock powder ,cold spray ,additive manufacturing ,Technology ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Microscopy ,QH201-278.5 ,Descriptive and experimental mechanics ,QC120-168.85 - Abstract
Gas-atomization is extensively used to produce metallic feedstock powders for additive manufacturing processes, including gas dynamic cold spray processing. This work explores the potential utility of on-demand recycled titanium scrap feedstock powder as a viable substitute for virgin powder sources. Three recycled titanium powders were atomized from different battlefield scrap sources using a mobile foundry developed by MolyWorks Materials Corporation. Recycled titanium alloy powders were compared against virgin Ti-6Al-4V powder to verify there were no significant variations between the recycled and virgin materials. Powder characterization methods included chemical analysis, particle size distribution analysis, scanning electron microscopy (SEM), Karl Fischer (KF) titration moisture content analysis, X-ray diffraction (XRD) phase analysis, microparticle compression testing (MCT), and nanoindentation. Results indicate that recycled titanium powder provides a viable alternative to virgin titanium alloy powders without compromising mechanical capabilities, microstructural features, or ASTM-specified composition and impurity standards. The results of this work will be used to aid future research efforts that will focus on optimizing cold spray parameters to maximize coating density, mechanical strength, and hardness of recycled titanium feedstock powders. “Cold spray” presents opportunities to enhance the sustainability of titanium component production through the utilization of recycled feedstock powder, mitigating issues of long lead times and high waste associated with the use of conventional virgin feedstock.
- Published
- 2024
- Full Text
- View/download PDF
48. Ontological Framework to Improve Motion Planning of Manipulative Agents through Semantic Knowledge-Based Reasoning.
- Author
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Rodrigo Bernardo, João M. C. Sousa, and Paulo J. S. Gonçalves
- Published
- 2023
49. Pattern recognition of hematological profiles of tumors of the digestive tract: an exploratory study
- Author
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Miguel A. Santos-Silva, Nuno Sousa, Marina Majar, Miguel Machado, Joana Reis, and Joao C. Sousa
- Subjects
cancer ,pattern recognition ,hematological profile ,anatomical location ,digestive tract tumor ,Medicine (General) ,R5-920 - Abstract
AimsIn this study, we aimed to apply laboratory blood analysis to identify the hematological (based on hemoglobin concentration, erythrocytes, hematocrit, and RDW count) profiles associated with the most prevalent forms of digestive tract malignancies. Furthermore, we aimed to evaluate how these profiles contributed to distinguishing these tumors at diagnosis.MethodsWe collected data from the date of ICD-10 diagnostic coding for C15 esophagus, C16 stomach, C18 colon, and C19 rectum tumors of 184 individuals. The statistical analysis and data visualization approaches, notably the heat map and principal component analysis (PCA), allowed for creating a summary hematological profile and identifying the most associated parameters for each pathologic state. Univariate and multivariate data modeling and ROC analysis were performed in both SPSS and Python.ResultsOur data reveal unique patterns based on tumor development anatomical location, clustering the C18 colon and C19 rectum from the C15 esophagus and C16 stomach. We found a significant difference between C16 stomach carcinoma and the other tumors, which substantially correlated with raised RDW in conjunction with low hemoglobin concentration, erythrocytes, and hematocrit counts. In contrast, C18 colon carcinoma had the higher red blood cell count, allowing for the best classification metrics in the test set of the binary logistic regression (LR) model, accounting for an AUC of 0.77 with 94% sensitivity and 52% specificity.ConclusionThis study emphasizes the significance of adding hematological patterns in diagnosing these malignancies, which could path further investigations regarding profiling and monitoring at the point of care.
- Published
- 2023
- Full Text
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50. Ground state solutions for electromagnetic Schrödinger equations on unbounded domains
- Author
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Zuo, Jiabin, Khachnaoui, Khaled, and da C. Sousa, J. Vanterler
- Published
- 2023
- Full Text
- View/download PDF
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