Search results for: Jorge Andrés Cormane Angarita

Authors: Fabio Rodriguez Sanchez, Josef Bruers, Iciar Arteagoitia, Carlos Rodriguez Andres

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Background: Oral implants are a routine treatment to replace lost teeth. Although they have a high rate of success, implant failures do occur. Perioperative antibiotics have been suggested to prevent postoperative infections and dental implant failures, but they remain a controversial treatment among healthy patients. The objective of this study was to determine whether antibiotic prophylaxis is a common treatment in the Netherlands among general dentists, maxillofacial-surgeons, periodontists and implantologists in conjunction with oral implant surgery among healthy patients and to assess the nature of antibiotics prescriptions in order to evaluate whether any consensus has been reached and the current recommendations are being followed. Methodology: Observational cross-sectional study based on a web-survey reported according to the Strengthening the Reporting of Observational studies in Epidemiology (STROBE) guidelines. A validated questionnaire, developed by Deeb et al. (2015), was translated and slightly adjusted to circumstances in the Netherlands. It was used with the explicit permission of the authors. This questionnaire contained both close-ended and some open-ended questions in relation to the following topics: demographics, qualification, antibiotic type, prescription-duration and dosage. An email was sent February 2018 to a sample of 600 general dentists and all 302 oral implantologists, periodontists and maxillofacial surgeons who were recognized by the Dutch Association of Oral Implantology (NVOI) as oral health care providers placing oral implants. The email included a brief introduction about the study objectives and a link to the web questionnaire, which could be filled in anonymously. Overall, 902 questionnaires were sent. However, 29 questionnaires were not correctly received due to an incorrect email address. So a total number of 873 professionals were reached. Collected data were analyzed using SPSS (IBM Corp., released 2012, Armonk, NY). Results: The questionnaire was sent back by a total number of 218 participants (response rate=24.2%), 45 female (20.8%) and 171 male (79.2%). Two respondents were excluded from the study group because they were not currently working as oral health providers. Overall 151 (69.9%) placed oral implants on regular basis. Approximately 79 (52.7%) of these participants prescribed antibiotics only in determined situations, 66 (44.0%) prescribed antibiotics always and 5 dentists (3.3%) did not prescribe antibiotics at all when placing oral implants. Overall, 83 participants who prescribed antibiotics, did so both pre- and postoperatively (58.5%), 12 exclusively postoperative (8.5%), and 47 followed an exclusive preoperative regime (33.1%). A single dose of 2,000 mg amoxicillin orally 1-hour prior treatment was the most prescribed preoperative regimen. The most frequent prescribed postoperative regimen was 500 mg amoxicillin three times daily for 7 days after surgery. On average, oral health professionals prescribed 6,923 mg antibiotics in conjunction with oral implant surgery, varying from 500 to 14,600 mg. Conclusions: Antibiotic prophylaxis in conjunction with oral implant surgery is prescribed in the Netherlands on a rather large scale. Dutch professionals might prescribe antibiotics more cautiously than in other countries and there seems to be a lower range on the different antibiotic types and regimens being prescribed. Anyway, recommendations based on last-published evidence are frequently not being followed.

Keywords: clinical decision making, infection control, antibiotic prophylaxis, dental implants

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Authors: Fernanda Gonçalves, Karla Alcântara, Vanessa Moura, Patrícia Nolasco, Jorge Kalil, Maristela Hernandez

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Introduction: Atherosclerosis is a chronic disease where two striking features are observed: retention of lipids and inflammation. Understanding the interaction between immune cells and lipoproteins involved in atherogenesis are urgent challenges, since cardiovascular diseases are the leading cause of death worldwide. Macrophages are critical to the development of atherosclerotic plaques and in the perpetuation of inflammation in these lesions. These cells are also directly involved in unstable plaque rupture. Recently different populations of macrophages are being identified in atherosclerotic lesions. Although the presence of M2 macrophages (macrophages activated by the alternative pathway, eg. The IL-4) has been identified, the function of these cells in atherosclerosis is not yet defined. M2 macrophages have a high endocytic capacity, they promote remodeling of tissues and to have anti-inflammatory activity. However, in atherosclerosis, especially unstable plaques, severe inflammatory reaction, accumulation of cellular debris and intense degradation of the tissue is observed. Thus, it is possible that the M2 macrophages have altered function (phenotype) in atherosclerosis. Objective: Our aim is to evaluate if the presence of oxidized LDL alters the phenotype and function of M2 macrophages in vitro. Methods: For this, we will evaluate whether the addition of lipoprotein in M2 macrophages differentiated in vitro with IL -4 induces 1) a reduction in the secretion of anti-inflammatory cytokines (CBA and ELISA), 2) secretion of inflammatory cytokines (CBA and ELISA), 3) expression of cell activation markers (Flow cytometry), 4) alteration in gene expression of molecules adhesion and extracellular matrix (Real-Time PCR) and 5) Matrix degradation (confocal microscopy). Results: In oxLDL stimulated M2 macrophages cultures we did not find any differences in the expression of the cell surface markers tested, including: HLA-DR, CD80, CD86, CD206, CD163 and CD36. Also, cultures stimulated with oxLDL had similar phagocytic capacity when compared to unstimulated cells. However, in the supernatant of these cultures an increase in the secretion of the pro-inflammatory cytokine IL-8 was detected. No significant changes where observed in IL-6, IL-10, IL-12 and IL-1b levels. The culture supernatant also induced massive extracellular matrix (produced by mouse embryo fibroblast) filaments degradation. When evaluating the expression of 84 extracellular matrix and adhesion molecules genes, we observed that the stimulation of oxLDL in M2 macrophages decreased 47% of the genes and increased the expression of only 3% of the genes. In particular we noted that oxLDL inhibit the expression of 60% of the genes constituents of extracellular matrix and collagen expressed by these cells, including fibronectin1 and collagen VI. We also observed a decrease in the expression of matrix protease inhibitors, such as TIMP 2. On the opposite, the matricellular protein thrombospondin had a 12 fold increase in gene expression. In the presence of native LDL 90% of the genes had no altered expression. Conclusion: M2 macrophages stimulated with oxLDL secrete the pro-inflammatory cytokine IL-8, have an altered extracellular matrix constituents gene expression, and promote the degradation of extracellular matrix. M2 macrophages may contribute to the perpetuation of inflammation in atherosclerosis and to plaque rupture.

Keywords: atherosclerosis, LDL, macrophages, m2

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Authors: Mario Tauzene Afonso Matangue, Ivan Andres Sanchez Ortiz

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The Metropolitan area of Maputo (Mozambique Capital City) is located in semi-arid zone (800 mm annual rainfall) with 1101170 million inhabitants. On the west side, there are the flatlands of Infulene where the Mulauze River flows towards to the Indian Ocean, receiving at this site, the storm water contaminated with sanitary sewage from Maputo, transported through a concrete open channel. In Infulene, local communities grow salads crops such as tomato, onion, garlic, lettuce, and cabbage, which are then commercialized and consumed in several markets in Maputo City. Lettuce is the most daily consumed salad crop in different meals, generally in fast-foods, breakfasts, lunches, and dinners. However, the risk of infection by several pathogens due to the consumption of lettuce, using the Quantitative Microbial Risk Assessment (QMRA) tools, is still unknown since there are few studies or publications concerning to this matter in Mozambique. This work is aimed at determining the annual risk arising from the consumption of lettuce grown in Infulene valley, in Maputo, using QMRA tools. The exposure model was constructed upon the volume of contaminated water remaining in the lettuce leaves, the empirical relations between the number of pathogens and the indicator of microorganisms (E. coli), the consumption of lettuce (g) and reduction of pathogens (days). The reference pathogens were Vibrio cholerae, Cryptosporidium, norovirus, and Ascaris. The water quality samples (E. coli) were collected in the storm water channel from January 2016 to December 2018, comprising 65 samples, and the urban lettuce consumption data were collected through inquiry in Maputo Metropolis covering 350 persons. A non-parametric bootstrap was performed involving 10,000 iterations over the collected dataset, namely, water quality (E. coli) and lettuce consumption. The dose-response models were: Exponential for Cryptosporidium, Kummer Confluent hypergeomtric function (1F1) for Vibrio and Ascaris Gaussian hypergeometric function (2F1-(a,b;c;z) for norovirus. The annual infection risk estimates were performed using R 3.6.0 (CoreTeam) software by Monte Carlo (Latin hypercubes), a sampling technique involving 10,000 iterations. The annual infection risks values expressed by Median and the 95th percentile, per person per year (pppy) arising from the consumption of lettuce are as follows: Vibrio cholerae (1.00, 1.00), Cryptosporidium (3.91x10⁻³, 9.72x 10⁻³), nororvirus (5.22x10⁻¹, 9.99x10⁻¹) and Ascaris (2.59x10⁻¹, 9.65x10⁻¹). Thus, the consumption of the lettuce would result in greater risks than the tolerable levels ( < 10⁻³ pppy or 10⁻⁶ DALY) for all pathogens, and the Vibrio cholerae is the most virulent pathogens, according to the hit-single models followed by the Ascaris lumbricoides and norovirus. The sensitivity analysis carried out in this work pointed out that in the whole QMRA, the most important input variable was the reduction of pathogens (Spearman rank value was 0.69) between harvest and consumption followed by water quality (Spearman rank value was 0.69). The decision-makers (Mozambique Government) must strengthen the prevention measures related to pathogens reduction in lettuce (i.e., washing) and engage in wastewater treatment engineering.

Keywords: annual infections risk, lettuce, non-parametric bootstrapping, quantitative microbial risk assessment tools

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Authors: Laura Alvarez-Alonso, Francisco Garcia-Carro, Jorge Loredo

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Population growth and industrial development imply an increase in the energy demands and the problems caused by emissions of greenhouse effect gases, which has inspired the search for clean sources of energy. Hydrogen (H₂) is expected to play a key role in the world’s energy future by replacing fossil fuels. The properties of H₂ make it a green fuel that does not generate pollutants and supplies sufficient energy for power generation, transportation, and other applications. Supercritical Water Gasification (SCWG) represents an attractive alternative for the recovery of energy from wastes. SCWG allows conversion of a wide range of raw materials into a fuel gas with a high content of hydrogen and light hydrocarbons through their treatment at conditions higher than those that define the critical point of water (temperature of 374°C and pressure of 221 bar). Methane used as a transport fuel is another important gasification product. The number of different uses of gas and energy forms that can be produced depending on the kind of material gasified and type of technology used to process it, shows the flexibility of SCWG. This feature allows it to be integrated with several industrial processes, as well as power generation systems or waste-to-energy production systems. The final aim of this work is to study which conditions and equipment are the most efficient and advantageous to explore the possibilities to obtain streams rich in H₂ from oily wastes, which represent a major problem both for the environment and human health throughout the world. In this paper, the relative complexity of technology needed for feasible gasification process cycles is discussed with particular reference to the different feedstocks that can be used as raw material, different reactors, and energy recovery systems. For this purpose, a review of the current status of SCWG technologies has been carried out, by means of different classifications based on key features as the feed treated or the type of reactor and other apparatus. This analysis allows to improve the technology efficiency through the study of model calculations and its comparison with experimental data, the establishment of kinetics for chemical reactions, the analysis of how the main reaction parameters affect the yield and composition of products, or the determination of the most common problems and risks that can occur. The results of this work show that SCWG is a promising method for the production of both hydrogen and methane. The most significant choices of design are the reactor type and process cycle, which can be conveniently adopted according to waste characteristics. Regarding the future of the technology, the design of SCWG plants is still to be optimized to include energy recovery systems in order to reduce costs of equipment and operation derived from the high temperature and pressure conditions that are necessary to convert water to the SC state, as well as to find solutions to remove corrosion and clogging of components of the reactor.

Keywords: hydrogen production, organic wastes, supercritical water gasification, system integration, waste-to-energy

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Authors: Fernanda Bravo Cornejo, Camilo Cerda Sarabia, Belén Díaz Díaz, Diego Santibañez Oyarce, Esteban Gómez Terán, Hugo Osses Prado, Raúl Caulier-Cisterna, Jorge Vergara-Quezada, Ana Moya-Beltrán

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Streptococcus pyogenes is a gram-positive bacteria involved in a wide range of diseases and is a major-human-specific bacterial pathogen. In Chile, this year the 'Ministerio de Salud' declared an alert due to the increase in strains throughout the year. This increase can be attributed to the multitude of factors including antimicrobial resistance (AMR) and Virulence Factors (VF). Understanding these VF and AMR is crucial for developing effective strategies and improving public health responses. Moreover, experimental identification and characterization of these pathogenic mechanisms are labor-intensive and time-consuming. Therefore, new computational methods are required to provide robust techniques for accelerating this identification. Advances in Machine Learning (ML) algorithms represent the opportunity to refine and accelerate the discovery of VF associated with Streptococcus pyogenes. In this work, we evaluate the accuracy of various machine learning models in predicting the virulence factors and antimicrobial resistance of Streptococcus pyogenes, with the objective of providing new methods for identifying the pathogenic mechanisms of this organism.Our comprehensive approach involved the download of 32,798 genbank files of S. pyogenes from NCBI dataset, coupled with the incorporation of data from Virulence Factor Database (VFDB) and Antibiotic Resistance Database (CARD) which contains sequences of AMR gene sequence and resistance profiles. These datasets provided labeled examples of both virulent and non-virulent genes, enabling a robust foundation for feature extraction and model training. We employed preprocessing, characterization and feature extraction techniques on primary nucleotide/amino acid sequences and selected the optimal more for model training. The feature set was constructed using sequence-based descriptors (e.g., k-mers and One-hot encoding), and functional annotations based on database prediction. The ML models compared are logistic regression, decision trees, support vector machines, neural networks among others. The results of this work show some differences in accuracy between the algorithms, these differences allow us to identify different aspects that represent unique opportunities for a more precise and efficient characterization and identification of VF and AMR. This comparative analysis underscores the value of integrating machine learning techniques in predicting S. pyogenes virulence and AMR, offering potential pathways for more effective diagnostic and therapeutic strategies. Future work will focus on incorporating additional omics data, such as transcriptomics, and exploring advanced deep learning models to further enhance predictive capabilities.

Keywords: antibiotic resistance, streptococcus pyogenes, virulence factors., machine learning

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Authors: Michel Patiño-Sáenz, Martín Haissiner, Jorge Martínez-Cotrina, Daniel Pastor, Hernando Santamaría-García, Maria-Alejandra Tangarife, Agustin Ibáñez, Sandra Baez

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It has been shown that gruesome descriptions of harm can increase the punishment given to a transgressor. This biasing effect is mediated by negative emotions, which are elicited upon the presentation of gruesome descriptions. However, there is a lack of studies inquiring the influence of such descriptions on moral decision-making in people involved in the criminal justice system. Such populations are of special interest since they have experience dealing with gruesome evidence, but also formal education on how to assess evidence and gauge the appropriate punishment according to the law. Likewise, they are expected to be objective and rational when performing their duty, because their decisions can impact profoundly people`s lives. Considering these antecedents, the objective of this study was to explore the influence gruesome written descriptions on moral decision-making in this group of people. To that end, we recruited attorneys, judges and public prosecutors (Criminal justice group, CJ, n=30) whose field of specialty is criminal law. In addition, we included a control group of people who did not have a formal education in law (n=30), but who were paired in age and years of education with the CJ group. All participants completed an online, Spanish-adapted version of a moral decision-making task, which was previously reported in the literature and also standardized and validated in the Latin-American context. A series of text-based stories describing two characters, one inflicting harm on the other, were presented to participants. Transgressor's intentionality (accidental vs. intentional harm) and language (gruesome vs. plain) used to describe harm were manipulated employing a within-subjects and a between-subjects design, respectively. After reading each story, participants were asked to rate (a) the harmful action's moral adequacy, (b) the amount of punishment deserving the transgressor and (c) how damaging was his behavior. Results showed main effects of group, intentionality and type of language on all dependent measures. In both groups, intentional harmful actions were rated as significantly less morally adequate, were punished more severely and were deemed as more damaging. Moreover, control subjects deemed more damaging and punished more severely any type of action than the CJ group. In addition, there was an interaction between intentionality and group. People in the control group rated harmful actions as less morally adequate than the CJ group, but only when the action was accidental. Also, there was an interaction between intentionality and language on punishment ratings. Controls punished more when harm was described using gruesome language. However, that was not the case of people in the CJ group, who assigned the same amount of punishment in both conditions. In conclusion, participants with job experience in the criminal justice system or criminal law differ in the way they make moral decisions. Particularly, it seems that they are less sensitive to the biasing effect of gruesome evidence, which is probably explained by their formal education or their experience in dealing with such evidence. Nonetheless, more studies are needed to determine the impact this phenomenon has on the fulfillment of their duty.

Keywords: criminal justice system, emotions, gruesome descriptions, intentionality, moral decision-making

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Authors: Jorge Cortés, Alejandra Martínez, Carlos Pérez, Anaid Simón

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The presence of government, news media, and general citizenry in social media allows considering interactions between them as a form of political communication (i.e. the public exchange of contradictory discourses about politics). Twitter’s asymmetrical following model (users can follow, mention or reply to other users that do not follow them) could foster alternative democratic practices and have an impact on Mexican political culture, which has been marked by a lack of direct communication channels between these actors. The research aim is to assess Twitter’s role in political communication practices through the analysis of interaction dynamics between government, news media, and citizens by extracting and visualizing data from Twitter’s API to observe general behavior patterns. The hypothesis is that regardless the fact that Twitter’s features enable direct and horizontal interactions between actors, users repeat traditional dynamics of interaction, without taking full advantage of the possibilities of this medium. Through an interdisciplinary team including Communication Strategies, Information Design, and Interaction Systems, the activity on Twitter generated by the controversy over the presence of Uber in Mexico City was analysed; an issue of public interest, involving aspects such as public opinion, economic interests and a legal dimension. This research includes techniques from social network analysis (SNA), a methodological approach focused on the comprehension of the relationships between actors through the visual representation and measurement of network characteristics. The analysis of the Uber event comprised data extraction, data categorization, corpus construction, corpus visualization and analysis. On the recovery stage TAGS, a Google Sheet template, was used to extract tweets that included the hashtags #UberSeQueda and #UberSeVa, posts containing the string Uber and tweets directed to @uber_mx. Using scripts written in Python, the data was filtered, discarding tweets with no interaction (replies, retweets or mentions) and locations outside of México. Considerations regarding bots and the omission of anecdotal posts were also taken into account. The utility of graphs to observe interactions of political communication in general was confirmed by the analysis of visualizations generated with programs such as Gephi and NodeXL. However, some aspects require improvements to obtain more useful visual representations for this type of research. For example, link¬crossings complicates following the direction of an interaction forcing users to manipulate the graph to see it clearly. It was concluded that some practices prevalent in political communication in Mexico are replicated in Twitter. Media actors tend to group together instead of interact with others. The political system tends to tweet as an advertising strategy rather than to generate dialogue. However, some actors were identified as bridges establishing communication between the three spheres, generating a more democratic exercise and taking advantage of Twitter’s possibilities. Although interactions in Twitter could become an alternative to political communication, this potential depends on the intentions of the participants and to what extent they are aiming for collaborative and direct communications. Further research is needed to get a deeper understanding on the political behavior of Twitter users and the possibilities of SNA for its analysis.

Keywords: interaction, political communication, social network analysis, Twitter

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Authors: Joana Pimenta, Lorena Coelho, José Silva, Vanessa Miranda, Jorge Laranjeira, Rui Soares

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In this paper, the results of R&D on an innovative food package for increased shelf-life are presented. SAP4MA aims at the development of a printed active device that enables smart packaging solutions for food preservation, targeting the extension of the shelf-life of the packed food through the controlled release of active natural antioxidant agents at the onset of the food degradation process. To do so, SAP4MA focuses on the development of active devices such as printed heaters and batteries/supercapacitors in a label format to be integrated on packaging lids during its injection molding process, promoting the passive release of natural antioxidants after the product is packed, during transportation and in the shelves, and actively when the end-user activates the package, just prior to consuming the product at home. When the active device present on the lid is activated, the release of the natural antioxidants embedded in the inner layer of the packaging lid in direct contact with the headspace atmosphere of the food package starts. This approach is based on the use of active functional coatings composed of nano encapsulated active agents (natural antioxidants species) in the prevention of the oxidation of lipid compounds in food by agents such as oxygen. Thus keeping the product quality during the shelf-life, not only when the user opens the packaging, but also during the period from food packaging up until the purchase by the consumer. The active systems that make up the printed smart label, heating circuit, and battery were developed using screen-printing technology. These systems must operate under the working conditions associated with this application. The printed heating circuit was studied using three different substrates and two different conductive inks. Inks were selected, taking into consideration that the printed circuits will be subjected to high pressures and temperatures during the injection molding process. The circuit must reach a homogeneous temperature of 40ºC in the entire area of the lid of the food tub, promoting a gradual and controlled release of the antioxidant agents. In addition, the circuit design involves a high level of study in order to guarantee maximum performance after the injection process and meet the specifications required by the control electronics component. Furthermore, to characterize the different heating circuits, the electrical resistance promoted by the conductive ink and the circuit design, as well as the thermal behavior of printed circuits on different substrates, were evaluated. In the injection molding process, the serpentine-shaped design developed for the heating circuit was able to resolve the issues connected to the injection point; in addition, the materials used in the support and printing had high mechanical resistance against the pressure and temperature inherent to the injection process. Acknowledgment: This research has been carried out within the Project “Smart and Active Packing for Margarine Product” (SAP4MA) running under the EURIPIDES Program being co-financed by COMPETE 2020 – the Operational Programme for Competitiveness and Internationalization and under Portugal 2020 through the European Regional Development Fund (ERDF).

Keywords: smart package, printed heat circuits, printed batteries, flexible and printed electronic

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Authors: Lizeth Fuentes-Mera, Vanessa Perez-Silos, Nidia K. Moncada-Saucedo, Alejandro Garcia-Ruiz, Alberto Camacho, Jorge Lara-Arias, Ivan Marino-Martinez, Victor Romero-Diaz, Adolfo Soto-Dominguez, Humberto Rodriguez-Rocha, Hang Lin, Victor Pena-Martinez

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Biphasic scaffolds in cartilage tissue engineering have been designed to influence not only the recapitulation of the osteochondral architecture but also to take advantage of the healing ability of bone to promote the implant integration with the surrounding tissue and then bone restoration and cartilage regeneration. This study reports the development and characterization of a biphasic scaffold based on the assembly of a cartilage phase constituted by fibroin biofunctionalized with bovine cartilage matrix; cellularized with differentiated pre-chondrocytes from adipose tissue stem cells (autologous) and well attached to a bone phase (bone bovine decellularized) to mimic the structure of the nature of native tissue and to promote the cartilage regeneration in a model of joint damage in pigs. Biphasic scaffolds were assembled by fibroin crystallization with methanol. The histological and ultrastructural architectures were evaluated by optical and scanning electron microscopy respectively. Mechanical tests were conducted to evaluate Young's modulus of the implant. For the biological evaluation, pre-chondrocytes were loaded onto the scaffolds and cellular adhesion, proliferation, and gene expression analysis of cartilage extracellular matrix components was performed. The scaffolds that were cellularized and matured for 10 days were implanted into critical 3 mm in diameter and 9-mm in depth osteochondral defects in a porcine model (n=4). Three treatments were applied per knee: Group 1: monophasic cellular scaffold (MS) (single chondral phase), group 2: biphasic scaffold, cellularized only in the chondral phase (BS1), group 3: BS cellularized in both bone and chondral phases (BS2). Simultaneously, a control without treatment was evaluated. After 4 weeks of surgery, integration and regeneration tissues were analyzed by x-rays, histology and immunohistochemistry evaluation. The mechanical assessment showed that the acellular biphasic composites exhibited Young's modulus of 805.01 kPa similar to native cartilage (400-800 kPa). In vitro biological studies revealed the chondroinductive ability of the biphasic implant, evidenced by an increase in sulfated glycosaminoglycan (GAGs) and type II collagen, both secreted by the chondrocytes cultured on the scaffold during 28 days. No evidence of adverse or inflammatory reactions was observed in the in vivo trial; however, In group 1, the defects were not reconstructed. In group 2 and 3 a good integration of the implant with the surrounding tissue was observed. Defects in group 2 were fulfilled by hyaline cartilage and normal bone. Group 3 defects showed fibrous repair tissue. In conclusion; our findings demonstrated the efficacy of biphasic and bioactive scaffold based on silk fibroin, which entwined chondroinductive features and biomechanical capability with appropriate integration with the surrounding tissue, representing a promising alternative for osteochondral tissue-engineering applications.

Keywords: biphasic scaffold, extracellular cartilage matrix, silk fibroin, osteochondral tissue engineering

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Authors: Jorge Ferro-Diaz, Lazaro Marquez-Llauger, Jose Alberto Camejo-Lamas, Lazaro Marquez-Govea

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The invasion of Scaevola sericea Vahl (Goodeniaceae) in Cuba is a recent process, this exotic invasive species was reported for the first time, in the national territory, by 2008. S. sericea is native to the coasts around the Indian Ocean and western Pacific, common on sandy beaches; it has expanded rapidly around the planet by either natural or anthropic causes, mainly due to its use in hotel gardening. Cuba is highly vulnerable to the colonization of these species, mainly due to tropical hurricanes which have increased in the last decades; it also affects other native species such as Tournefortia gnaphalodes (L.) R. Br. (Boraginaceae) that show invasive manifestations because of the unbalanced state of demographic processes of littoral vegetation, which has been studied by authors during the last 10 years. The fast development of Cuban tourism has encouraged the use of exotic species in gardening that invade large sectors of sandy coasts. Taking into account the importance of assessing the impacts dimensions and adopting effective control measures, a monitoring program for the invasion of S. sericea in Cuba was undertaken. The program has been implemented since 2013 and the main objective was to identify invasive patterns and interactions with other native species of coastal vegetation. This experience also aimed to validate the design and propose a standardized monitoring protocol to be applied throughout the country. In the Cuban territory, 12 sites were chosen, where there were established 24 permanent plots of 100 m2; measurements were taken twice a year taking into consideration variables such as abundance, plant height, soil cover, flora and companion vegetation, density and frequency; other physical variables of the beaches were also measured. Similarly, for associated individuals of T. gnaphalodes, the same variables were measured. The results of these first four years allowed us to document patterns of S. sericea invasion, highlighting the use of adventitious roots to enhance their colonization, and to characterize demographic indicators, ecosystem affections, and interactions with native plants. A density-dependent relationship with T. gnaphalodes was documented, finding a controlling effect on S. sericea, so that a manipulation experiment was applied to evaluate possible management actions to be incorporated in the Plans of the protected areas involved. With these results, it was concluded, for the evaluated sites, that S. sericea has had an invasion dynamics ruled by effects of coastal dynamics, more intense in beaches with affectations to the native vegetation, and more controlled in beaches with more preserved vegetation. It was found that when S. sericea is established, the mechanism that most reinforces its invasion is the use of adventitious roots, used to expand the patches and colonize beach sectors. It was also found that when the density of T. gnaphalodes increases, it detains the expansion of S. sericea and reduces its colonization possibilities, behaving as a natural controller of its biological invasion. The results include a proposal of a new Monitoring Protocol for Scaevola sericea in Cuba, with the possibility of extending its implementation to other countries in the region.

Keywords: biological invasion, exotic invasive species, plant interactions, Scaevola sericea

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Authors: Madalena Corte-real, João Pedro Nunes, Bernardo Fernandes, Ana Jorge Correira

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This presentation looks, from a sociological perspective, at neighboring practices in the inner city of Lisbon. The capital of Portugal, with half a million inhabitants, inserted in a metropolitan area with almost 2,9 million people, has been in the international spotlight seen as an interesting city to live in and to invest in, especially in the real estate market. This promotion emerged in the context of the financial crisis, where local authorities aimed to make Lisbon a more competitive city, calling for visitors and financial and human capital. Especially in the last decade, Portugal’s capital has been experiencing a significant increase in terms of migration from creative and entrepreneurial exiles to economic and political expats. In this context, the territory under analysis, in particular, is a mixed-used area undergoing rapid transformations in recent years marked by the presence of newcomers and non-nationals as well as social and cultural heterogeneity. It is next to one of the main arteries, considered the most multicultural part of the city, and presented in the press as one of the coolest neighborhoods in Europe. In view of these aspects, this research aims to address key-topics in current urban research: anonymity often related to big cities, socio-spatial attachment to the neighborhood, and the effects of diversity in the everyday relations of residents and shopkeepers. This case-study intends to look at particularities in local regimes differently affected by growing mobility. Against a backdrop of unidimensional generalizations and a tendency to refer to central countries and global cities, it aims to discuss national and local specificities. In methodological terms, the project comprises essentially a qualitative approach that consists of direct observation techniques and ethnographic methods as well semi-structured interviews to residents and local stakeholders whose narratives are subject to content analysis. The paper starts with a characterization of the broader context of the city of Lisbon, followed by territorial specificities regarding socio-spatial development, namely the city’s and the inner-areas morphology as well as the population’s socioeconomic profile. Following the residents and stakeholders’ narratives and practices it will assess the perception and behaviors regarding the representation of the area, relationships and experiences, routines, and sociability. Results point to a significant presence of neighborhood relations and different forms of support, in particular, among the different groups – e.g., old long-time residents, middle-class families, global creative class, and communities of economic migrants. Fieldwork reveals low levels of place-attachment although some residents refer, presently, high levels of satisfaction. Engagement with living space, this case-study suggests, reveals the social construction and lived the experience of neighboring by different groups, but also the way different and contrasting visions and desires are articulated to the profound urban, cultural and political changes that permeate the area.

Keywords: diversity, lisbon, neighboring and neighborhood, place-attachment

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Authors: Camilo Cerda Sarabia, Fernanda Bravo Cornejo, Diego Santibanez Oyarce, Hugo Osses Prado, Esteban Gómez Terán, Belén Diaz Diaz, Raúl Caulier-Cisterna, Jorge Vergara-Quezada, Ana Moya-Beltrán

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Antimicrobial resistance (AMR) represents a significant and rapidly escalating global health threat. Projections estimate that by 2050, AMR infections could claim up to 10 million lives annually. Respiratory infections, in particular, pose a severe risk not only to individual patients but also to the broader public health system. Despite the alarming rise in resistant respiratory infections, AMR within the lung microbiome (microbial community) remains underexplored and poorly characterized. The lungs, as a complex and dynamic microbial environment, host diverse communities of microorganisms whose interactions and resistance mechanisms are not fully understood. Unlike studies that focus on individual genomes, analyzing the entire microbiome provides a comprehensive perspective on microbial interactions, resistance gene transfer, and community dynamics, which are crucial for understanding AMR. However, this holistic approach introduces significant computational challenges and exposes the limitations of traditional analytical methods such as the difficulty of identifying the AMR. Machine learning has emerged as a powerful tool to overcome these challenges, offering the ability to analyze complex genomic data and uncover novel insights into AMR that might be overlooked by conventional approaches. This study investigates microbial resistance within the lung microbiome using unsupervised machine learning approaches to uncover resistance patterns and potential clinical associations. it downloaded and selected lung microbiome data from HumanMetagenomeDB based on metadata characteristics such as relevant clinical information, patient demographics, environmental factors, and sample collection methods. The metadata was further complemented by details on antibiotic usage, disease status, and other relevant descriptions. The sequencing data underwent stringent quality control, followed by a functional profiling focus on identifying resistance genes through specialized databases like Antibiotic Resistance Database (CARD) which contains sequences of AMR gene sequence and resistance profiles. Subsequent analyses employed unsupervised machine learning techniques to unravel the structure and diversity of resistomes in the microbial community. Some of the methods employed were clustering methods such as K-Means and Hierarchical Clustering enabled the identification of sample groups based on their resistance gene profiles. The work was implemented in python, leveraging a range of libraries such as biopython for biological sequence manipulation, NumPy for numerical operations, Scikit-learn for machine learning, Matplotlib for data visualization and Pandas for data manipulation. The findings from this study provide insights into the distribution and dynamics of antimicrobial resistance within the lung microbiome. By leveraging unsupervised machine learning, we identified novel resistance patterns and potential drivers within the microbial community.

Keywords: antibiotic resistance, microbial community, unsupervised machine learning., sequences of AMR gene

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Authors: Denise De Fátima Fernandes Barbosa, Tyane Mayara Ferreira Oliveira, Diego Jorge Maia Lima, Paula Renata Amorim Lessa, Ana Karina Bezerra Pinheiro, Cintia Gondim Pereira Calou, Glauberto Da Silva Quirino, Hellen Lívia Oliveira Catunda, Tatiana Gomes Guedes, Nicolau Da Costa

Abstract:

The aim of this study is to evaluate the use of Digital Cervicography (DC) in the diagnosis of precancerous lesions related to Human Papillomavirus (HPV). Cross-sectional study with a quantitative approach, of evaluative type, held in a health unit linked to the Pro Dean of Extension of the Federal University of Ceará, in the period of July to August 2015 with a sample of 33 women. Data collecting was conducted through interviews with enforcement tool. Franco (2005) standardized the technique used for DC. Polymerase Chain Reaction (PCR) was performed to identify high-risk HPV genotypes. DC were evaluated and classified by 3 judges. The results of DC and PCR were classified as positive, negative or inconclusive. The data of the collecting instruments were compiled and analyzed by the software Statistical Package for Social Sciences (SPSS) with descriptive statistics and cross-references. Sociodemographic, sexual and reproductive variables were analyzed through absolute frequencies (N) and their respective percentage (%). Kappa coefficient (κ) was applied to determine the existence of agreement between the DC of reports among evaluators with PCR and also among the judges about the DC results. The Pearson's chi-square test was used for analysis of sociodemographic, sexual and reproductive variables with the PCR reports. It was considered statistically significant (p<0.05). Ethical aspects of research involving human beings were respected, according to 466/2012 Resolution. Regarding the socio-demographic profile, the most prevalent ages and equally were those belonging to the groups 21-30 and 41-50 years old (24.2%). The brown color was reported in excess (84.8%) and 96.9% out of them had completed primary and secondary school or studying. 51.5% were married, 72.7% Catholic, 54.5% employed and 48.5% with income between one and two minimum wages. As for the sexual and reproductive characteristics, prevailed heterosexual (93.9%) who did not use condoms during sexual intercourse (72.7%). 51.5% had a previous history of Sexually Transmitted Infection (STI), and HPV the most prevalent STI (76.5%). 57.6% did not use contraception, 78.8% underwent examination Cancer Prevention Uterus (PCCU) with shorter time interval or equal to one year, 72.7% had no cases of Cervical Cancer in the family, 63.6% were multiparous and 97% were not vaccinated against HPV. DC identified good level of agreement between raters (κ=0.542), had a specificity of 77.8% and sensitivity of 25% when compared their results with PCR. Only the variable race showed a statistically significant association with CRP (p=0.042). DC had 100% acceptance amongst women in the sample, revealing the possibility of other experiments in using this method so that it proves as a viable technique. The DC positivity criteria were developed by nurses and these professionals also perform PCCU in Brazil, which means that DC can be an important complementary diagnostic method for the appreciation of these professional’s quality of examinations.

Keywords: gynecological examination, human papillomavirus, nursing, papillomavirus infections, uterine lasmsneop

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Authors: Dina Ibrahim Abouelamaiem, Ana Jorge Sobrido, Magdalena Titirici, Paul R. Shearing, Daniel J. L. Brett

Abstract:

Global warming and scarcity of fossil fuels have had a radical impact on the world economy and ecosystem. The urgent need for alternative energy sources has hence elicited an extensive research for exploiting efficient and sustainable means of energy conversion and storage. Among various electrochemical systems, supercapacitors attracted significant attention in the last decade due to their high power supply, long cycle life compared to batteries and simple mechanism. Recently, the performance of these devices has drastically improved, as tuning of nanomaterials provided efficient charge and storage mechanisms. Carbon materials, in various forms, are believed to pioneer the next generation of supercapacitors due to their attractive properties that include high electronic conductivities, high surface areas and easy processing and functionalization. Cellulose has eco-friendly attributes that are feasible to replace man-made fibers. The carbonization of cellulose yields carbons, including activated carbon and graphite fibers. Activated carbons successively are the most exploited candidates for supercapacitor electrode materials that can be complemented with pseudocapacitive materials to achieve high energy and power densities. In this work, the optimum functionalization conditions of cellulose have been investigated for supercapacitor electrode materials. The precursor was treated with potassium hydroxide (KOH) at different KOH/cellulose ratios prior to the carbonization process in an inert nitrogen atmosphere at 850 °C. The chalky products were washed, dried and characterized with different techniques including transmission electron microscopy (TEM), x-ray tomography and nitrogen adsorption-desorption isotherms. The morphological characteristics and their effect on the electrochemical performances were investigated in two and three-electrode systems. The KOH/cellulose ratios of 0.5:1 and 1:1 exhibited the highest performances with their unique hierarchal porous network structure, high surface areas and low cell resistances. Both samples acquired the best results in three-electrode systems and coin cells with specific gravimetric capacitances as high as 187 F g-1 and 20 F g-1 at a current density of 1 A g-1 and retention rates of 72% and 70%, respectively. This is attributed to the morphology of the samples that constituted of a well-balanced micro-, meso- and macro-porosity network structure. This study reveals that the electrochemical performance doesn’t solely depend on high surface areas but also an optimum pore size distribution, specifically at low current densities. The micro- and meso-pore contribution to the final pore structure was found to dominate at low KOH loadings, reaching ‘equilibrium’ with macropores at the optimum KOH loading, after which macropores dictate the porous network. The wide range of pore sizes is detrimental for the mobility and penetration of electrolyte ions in the porous structures. These findings highlight the influence of various morphological factors on the double-layer capacitances and high performance rates. In addition, they open a platform for the investigation of the optimized conditions for double-layer capacitance that can be coupled with pseudocapacitive materials to yield higher energy densities and capacities.

Keywords: carbon, electrochemical performance, electrodes, KOH/cellulose optimized ratio, morphology, supercapacitor

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Authors: Rachel Danielson, Brendan Bohannan, S.M. Tsai, Kyle Meyer, Jorge L.M. Rodrigues

Abstract:

The Amazon Rainforest is a global diversity hotspot and crucial carbon sink, but approximately 20% of its total extent has been deforested- primarily for the establishment of cattle pasture. Understanding the impact of this large-scale disturbance on soil microbial community composition and activity is crucial in understanding potentially consequential shifts in nutrient or greenhouse gas cycling, as well as adding to the body of knowledge concerning how these complex communities respond to human disturbance. In this study, surface soils (0-10cm) were collected from three forests and three 45-year-old pastures in Rondonia, Brazil (the Amazon state with the greatest rate of forest destruction) in order to determine the impact of forest conversion on microbial communities involved in nitrogen fixation. Soil chemical and physical parameters were paired with measurements of microbial activity and genetic profiles to determine how community composition and process rates relate to environmental conditions. Measuring both the natural abundance of 15N in total soil N, as well as incorporation of enriched 15N2 under incubation has revealed that conversion of primary forest to cattle pasture results in a significant increase in the rate of nitrogen fixation by free-living diazotrophs. Quantification of nifH gene copy numbers (an essential subunit encoding the nitrogenase enzyme) correspondingly reveals a significant increase of genes in pasture compared to forest soils. Additionally, genetic sequencing of both nifH genes and transcripts shows a significant increase in the diversity of the present and metabolically active diazotrophs within the soil community. Levels of both organic and inorganic nitrogen tend to be lower in pastures compared to forests, with ammonium rather than nitrate as the dominant inorganic form. However, no significant or consistent differences in total, extractable, permanganate-oxidizable, or loss-on-ignition carbon are present between the two land-use types. Forest conversion is associated with a 0.5- 1.0 unit pH increase, but concentrations of many biologically relevant nutrients such as phosphorus do not increase consistently. Increases in free-living diazotrophic community abundance and activity appear to be related to shifts in carbon to nitrogen pool ratios. Furthermore, there may be an important impact of transient, low molecular weight plant-root-derived organic carbon on free-living diazotroph communities not captured in this study. Preliminary analysis of nitrogenase gene variant composition using NovoSeq metagenomic sequencing indicates that conversion of forest to pasture may significantly enrich vanadium-based nitrogenases. This indication is complemented by a significant decrease in available soil molybdenum. Very little is known about the ecology of diazotrophs utilizing vanadium-based nitrogenases, so further analysis may reveal important environmental conditions favoring their abundance and diversity in soil systems. Taken together, the results of this study indicate a significant change in nitrogen cycling and diazotroph community composition with the conversion of the Amazon Rainforest. This may have important implications for the sustainability of cattle pastures once established since nitrogen is a crucial nutrient for forage grass productivity.

Keywords: free-living diazotrophs, land use change, metagenomic sequencing, nitrogen fixation

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Authors: Diogo José Morgado Rebelo, Francisco António Carneiro Pacheco de Andrade, Paulo Jorge Freitas de Oliveira Novais

Abstract:

Not everything in AI-power consumer credit scoring turns out to be a wonder. When using AI in Creditworthiness Assessment (CWA), opacity and unfairness ‘sins’ must be considered to the task be deemed Responsible. AI software is not always 100% accurate, which can lead to misclassification. Discrimination of some groups can be exponentiated. A hetero personalized identity can be imposed on the individual(s) affected. Also, autonomous CWA sometimes lacks transparency when using black box models. However, for this intended purpose, human analysts ‘on-the-loop’ might not be the best remedy consumers are looking for in credit. This study seeks to explore the legality of implementing a Multi-Agent System (MAS) framework in consumer CWA to ensure compliance with the regulation outlined in Article 14(4) of the Proposal for an Artificial Intelligence Act (AIA), dated 21 April 2021 (as per the last corrigendum by the European Parliament on 19 April 2024), Especially with the adoption of Art. 18(8)(9) of the EU Directive 2023/2225, of 18 October, which will go into effect on 20 November 2026, there should be more emphasis on the need for hybrid oversight in AI-driven scoring to ensure fairness and transparency. In fact, the range of EU regulations on AI-based consumer credit will soon impact the AI lending industry locally and globally, as shown by the broad territorial scope of AIA’s Art. 2. Consequently, engineering the law of consumer’s CWA is imperative. Generally, the proposed MAS framework consists of several layers arranged in a specific sequence, as follows: firstly, the Data Layer gathers legitimate predictor sets from traditional sources; then, the Decision Support System Layer, whose Neural Network model is trained using k-fold Cross Validation, provides recommendations based on the feeder data; the eXplainability (XAI) multi-structure comprises Three-Step-Agents; and, lastly, the Oversight Layer has a 'Bottom Stop' for analysts to intervene in a timely manner. From the analysis, one can assure a vital component of this software is the XAY layer. It appears as a transparent curtain covering the AI’s decision-making process, enabling comprehension, reflection, and further feasible oversight. Local Interpretable Model-agnostic Explanations (LIME) might act as a pillar by offering counterfactual insights. SHapley Additive exPlanation (SHAP), another agent in the XAI layer, could address potential discrimination issues, identifying the contribution of each feature to the prediction. Alternatively, for thin or no file consumers, the Suggestion Agent can promote financial inclusion. It uses lawful alternative sources such as the share of wallet, among others, to search for more advantageous solutions to incomplete evaluation appraisals based on genetic programming. Overall, this research aspires to bring the concept of Machine-Centered Anthropocentrism to the table of EU policymaking. It acknowledges that, when put into service, credit analysts no longer exert full control over the data-driven entities programmers have given ‘birth’ to. With similar explanatory agents under supervision, AI itself can become self-accountable, prioritizing human concerns and values. AI decisions should not be vilified inherently. The issue lies in how they are integrated into decision-making and whether they align with non-discrimination principles and transparency rules.

Keywords: creditworthiness assessment, hybrid oversight, machine-centered anthropocentrism, EU policymaking

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