Automotive Interior Sensing - Temporal Consistent Human Body Pose Estimation

Com o surgimento e desenvolvimento de veículos autónomos, surgiu igualmente uma necessidade de monitorizar e identificar objetos e ações que ocorrem no ambiente que rodeia o veículo. Este tipo de monitorização é particularmente importante no caso de veículos partilhados, dada a necessidade de identificar ações não só no exterior mas também no interior do veículo devido à ausência de um condutor humano que possa detetar, por exemplo, potenciais ações de violência entre passageiros e/ou situações onde estes necessitem de assistência. Englobado neste contexto, a Bosch desenvolveu uma solução de estimação de postura humana com o objetivo de extrapolar a pose de todos os ocupantes presentes numa dada imagem, inferir o comportamento de cada passageiro e, consequentemente, identificar ações potencialmente maliciosas. Porém, para que este algoritmo possa ser aplicado não apenas a imagens isoladas mas também a vídeos é necessário adicionar contexto temporal entre frames. Por outras palavras, é necessário associar a estimação de pose de uma dada pessoa para uma dada frame às estimações de pose para a mesma pessoa em frames subsequentes de modo a que a identificação dessa pessoa (ou qualquer outra presente numa dada frame) ao longo do vídeo seja correta e consistente. O tópico de associação temporal, também conhecido como "pose tracking", é abordado e desenvolvido ao longo do presente projeto, culminando na proposta e implementação de uma solução que melhora consideravelmente a consistência temporal do algoritmo de estimação de pose humana da Bosch. A solução desenvolvida utiliza uma mistura de abordagens clássicas e atuais de associação de informação, como por exemplo o "Hungarian algorithm" e "Intersection over Union", e abordagens de lógica de informação desenvolvidas especificamente para o caso em questão. A performance do algoritmo implementado no presente projeto é avaliada usando duas das mais recorrentes métricas de avaliação em casos de rastreamento de pose.With the emergence and development of autonomous vehicles, a necessity to constantly monitor and identify objects and action that occur in the surrounding environment of the vehicle itself was also created. This type of monitoring is particularly important in the case of shared vehicles, given the necessity to identify actions not only in the exterior but also in the interior of the vehicle due to the absence of a human driver that can detect, for instance, potential violent actions between passengers and/or cases where assistence is required. Encompassed in this context, Bosch has developed a human body pose estimation solution in order to extrapolate the pose of all vehicle occupants present in a given image, infere the behaviour of each passenger and, consequently, identify potentially malicious actions. However, in order to apply this algorithm not only to isolated images but also to videos it is necessary to add temporal context between frames. In other words, an association is required between the body pose estimation for a given person in a given frame and the body pose estimations for the same person in subsequent frames in order to ensure that the identification of that passenger (or any other passenger present in the same frame) is accurate and consistent throughout the entire video. The temporal association topic, also known as pose tracking, is addressed and developed during the present project, culminating in the proposal and implementation of a solution that considerably improves the temporal consistency of the human body pose estimation algorithm developed by Bosch. The implemented solution uses a mixture of currently relevant classical approaches for data association, such as the Hungarian algorithm e Intersection over Union techniques, and approaches based on data logic developed specifically for the present case. Regarding performance, the developed algorithm is evaluated using two of the most recurrent metrics for pose tracking methods

Desenvolvimento de vidros e de vidros cerâmicos sílico-fosfatados com elevado teor de alcalino-terrosos para aplicações biomédicas

A presente tese dá seguimento ao trabalho de mestrado realizado pelo mesmo autor. Pretendeu-se estudar os processos de separação de fases amorfas e de cristalização em vidros do sistema base SiO2-CaO-P2O5-MgO obtidos por fusão. Avaliou-se também como o comportamento in vitro de vidros e de vidros cerâmicos desse sistema, em especial a influência da estrutura nos primeiros e de características morfológicas nos segundos. A tese é constituída por um conjunto de artigos científicos apresentados em revistas da especialidade e em congressos. Os artigos estão agrupados em 3 capítulos (capítulos 2, 3 e 4) sendo a primeira secção de cada um deles constituída por uma introdução ao tema. No primeiro capítulo faz-se uma breve referência à evolução histórica da investigação em biovidros e biovidros cerâmicos e apresentam-se os materiais que foram objecto de estudo nesta tese. O segundo capítulo respeita a estudos de separação de fases amorfas e de cristalização em vidros. Os vidros bifásicos apresentam uma fase dispersa constituída por sílica amorfa, a qual tem uma morfologia peculiar – formações do tipo mórula. O desenvolvimento destas formações depende de parâmetros como a temperatura, o tempo de fusão e a composição química da matriz. Concluiu-se que a formação das mórulas resulta de um processo rápido de coalescência a partir de um número de formações existentes no fundido, característico da temperatura de fusão mas independente do tempo, e que as suas dimensões médias finais são função da viscosidade da fase contínua. Estudos com TiO2 permitiram concluir que a sua adição a um vidro monofásico do sistema SiO2-3CaO.P2O5-MgO provoca separação de fases amorfas e facilita a sua posterior cristalização. Com base na técnica de análise térmica diferencial (ATD) foram realizados estudos cinéticos de cristalização a temperatura variável num vidro bifásico (V4) de composição (% ponderal) SiO2 30, CaO 28,61, P2O5 24,14 e MgO 17,25. Através da aplicação de modelos teóricos concluiu-se que o processo de cristalização é constituído por duas etapas: nucleação (a » 730 °C) e crescimento de cristais (para temperaturas superiores a 800 °C), sendo a energia de activação do processo de crescimento de cristais elevada (» 763 kJ/mol) mas inferior à energia de activação de fluxo viscoso (» 1000 kJ/mol). Concluiu-se ainda ser aconselhável adaptar os modelos cinéticos às condições experimentais usadas na ATD. No terceiro capítulo são apresentados estudos de natureza estrutural subjacentes à compreensão do comportamento dos vidros em meio fisiológico sintético acelular. Através do recurso à técnica de ressonância magnética nuclear (RMN) foi identificada uma reacção de desproporcionação do silício, 2Q2- Q0 + Q4, em vidros com elevado teor de óxidos alcalino-terrosos. Esta reacção torna-se mais extensa à medida que a razão MgO/CaO aumenta. O fósforo está presente sob a forma de orto-fosfato. Neste capítulo é apresentado um outro estudo realizado com o objectivo de desenvolver um vidro monofásico com composição e estrutura idênticas às da matriz do vidro bifásico V4. O estudo da matriz do vidro V4 tem interesse na compreensão do processo de cristalização e da viscosidade (determinante do tamanho final das mórulas). O quarto capítulo é dedicado ao comportamento in vitro de vidros e de vidros cerâmicos. Analisou-se a influência da especiação do silício na bioactividade de vidros com a mesma conectividade de rede, tendo-se concluído que a sua presença modifica o comportamento in vitro destes materiais em virtude da diferente solubilidade das espécies Qn. Este comportamento promove os estágios 1-3 do mecanismo proposto por Hench. Embora seja um modificador, concluiu-se que o magnésio tem um papel estrutural diferente do desempenhado pelo cálcio, provocando um aumento da solubilidade dos vidros. O estudo do efeito da topografia e da presença de fases cristalinas no comportamento bioactivo dos vidros cerâmicos encerra esta tese. A existência de flutuações microestruturais e topográficas associada à presença de hidroxiapatite é responsável pela nucleação in vitro de apatite à superfície de vidros cerâmicos.This work extends the subject of the master thesis by the same author, its main aims being the study of the amorphous phase separation process and crystallisation in melted glasses of the SiO2-CaO-P2O5-MgO system. The in vitro behaviour of glasses and glass-ceramics was also evaluated, especially the influence of structure and morphological characteristics. This thesis is mainly composed by sets of scientific articles published in international journals and congresses. The papers are gathered in 3 chapters (Chapters 2, 3 and 4), the first section of each chapter being a introduction. In the first chapter a short historical overview of the development of bioactive glasses and glass-ceramics is presented together with the materials that were used in this investigation. The second chapter is dedicated to the amorphous phase separation and crystallisation in glasses. The two-phase glasses show a dispersed phase that is amorphous silica with a peculiar morphology – morular type formations. The development of these formations depends on melting temperature and time and on the chemical composition of the matrix. It was concluded that a fast coalescence process of a fixed amount of individual droplets was responsible for morulae formation. This fixed amount of droplets depends on melting temperature but is independent of the melting time. The final average morulae dimensions are a function of the matrix viscosity. Additions of TiO2 to an otherwise monophasic glass of the SiO2-3CaO.P2O5-MgO system were able to increase the overall crystallisation rates and to promote amorphous immiscibility in the system. The differential thermal analysis (DTA) technique coupled with theoretical models was used to study the non-isothermal crystallisation kinetics of a phase-separated glass (V4) of nominal composition (wt. %) 30 SiO2, 28.61 CaO, 24.14 P2O5, 17.25 MgO. It was concluded that the kinetics of crystallisation comprises two stages: a nucleation stage at about 730 °C and a particle growth stage for temperatures higher that 800 °C, the activation energy for growth being very high (» 763 kJ/mol) but still lower than the activation energy for viscous flow (» 1000 kJ/mol). It was also concluded that it is necessary to introduce modifications in the kinetic models in order to get a good agreement with the experimental DTA conditions. Chapter three reports structural studies of glasses in order to understand the bioactive properties of these materials. By magic-angle spinning (MAS) nuclear magnetic resonance (NMR) technique a silicon desproportionation reaction, 2Q2 Q0 + Q4, in alkalineearth rich glasses was identified. This reaction is more extensive as the MgO/CaO ratio increases. Besides Q species these glasses are composed by orthophosphate species. This chapter presents further work pursued in order to develop a monophasic glass with the same composition and structure of the matrix in two-phase glass V4. The interest for such material stems from the important role of the V4 glass matrix in the crystallisation behaviour and in the viscosity (which determines the final dimensions of the dispersed phase). The forth chapter presents in vitro studies of glasses and glass-ceramics. The influence of silicon speciation in the bioactivity of glasses with the same network connectivity is analysed and it is concluded that this phenomenon changes the behaviour of glasses due to the different solubilities of Qn species. This behaviour promotes the stages 1-3 of Hench’s mechanism. Although magnesium behaves as a modifier, it plays a structural role different from that played by calcium, the final result being an increase in glass solubility as the MgO/CaO ratio augments. The influence of morphology and nature of crystalline phases on the bioactive behaviour of some glass-ceramics was the last field addressed. It is proposed that microstructural fluctuations together with the presence of crystalline hydroxyapatite are responsible for in vitro apatite nucleation in glass-ceramics

Additive manufacturing of bioactive glass in a biodegradable matrix

Bioactive glass can induce a specific and fast response in the human body that supports tissue regeneration. It is possible to control the design of customized bioapplications with advanced technologies. Although currently used in research, only a few of these technologies have been approved by the FDA to be applied in Tissue Engineering. There is dedicated additive manufacturing equipment to manufacture biomaterials. Since they are emerging technologies in emerging fields of application it is necessary to study and develop formulations with suitable processing characteristics [1]. Formulations of bioactive glass (CaO·P2O5·MgO·SiO2 system) in two different biodegradable matrices (polylactide (PLA) and polycaprolactone (PCL)) were prepared and processed by material extrusion process, namely by Fused Filament Fabrication technique.. The polymer (PLA or PCL) involves bioactive particles in biocompatible media and allows to acquire extrudable skills. The formulations with different solid contents (20–50 wt.%) were prepared using a brabender mixer type and were characterized by different techniques (e.g., X-ray diffraction (XRD), differential scanning calorimetry (DSC), melt flow index (MFI)). The inorganic particles influence the rheological and thermal properties of bioactive glass composites. The viscosity decreases with the increase of bioactive glass content in the polymer matrix. Mechanical standard samples and scaffolds were printed and characterized. Bioactive glass composites until 40 wt.% of solid content can be printed. The bioactive glass improves the mechanical resistance of composites compared to a neat polymer matrix. However, formulations with high bioactive glass solid content (50 wt.%) showed printing limitations by their brittleness and clogging tendency.publishe

Formulation and characterization of potential composites filaments from PLA and tobacco stems for application in additive manufacturing

A tecnologia de fabricação por filamento fundido (FFF) utilizando polímeros como PLA e ABS é bem conhecida. Contudo, o desenvolvimento de filamentos compósitos para esta tecnologia de manufatura aditiva, bem como a determinação dos parâmetros de processamento e das propriedades resultantes na extrusão e na impressão 3D, ainda requerem pesquisa. Esse estudo exploratório analisa as propriedades químicas, térmicas e a morfologia de filamento de matriz polimérica de PLA e talos de tabaco, visando sua utilização no processo FFF. Os materiais utilizados foram talos de tabaco moídos e PLA. As partículas de tabaco, com tamanho médio de 50 m, apresentaram-se aleatoriamente distribuídas no filamento. No entanto, aglomerados de partículas, bolhas e porosidades foram observados no centro do filamento. Ensaios por espectroscopia no infravermelho por transformada de Fourier mostraram que o filamento compósito apresentou interação mecânica entre os materiais. A análise térmica permitiu verificar que não houve degradação do pó de talos de tabaco, mantendo a integridade química e física do filamento compósito a temperatura de extrusão de 180 °C. A calorimetria exploratória diferencial revelou que as partículas de pó de talos de tabaco podem ter atuado como agente nucleante, aumentando o grau de cristalinidade do filamento compósito. Sugere-se para estudos futuros o aumento do percentual de pó de talos de tabaco, a investigação de outros métodos de preparação de compósitos, bem como um estudo da adição de plastificantes ou agentes compatibilizantes para aprimorar a ligação entre a interface do PLA e as partículas de tabaco.Fused filament fabrication (FFF) using polymers such as PLA and ABS are well known. However, the development of composite filaments for this type of additive manufacturing technology, as well as the study of processing parameters and properties resulting from extrusion process and printing still require investigation. This exploratory research aims to analyze chemical and thermal properties and the morphology of a composite filament from PLA polymer matrix and tobacco stems to seek its use in the FFF process. The materials used were waste of tobacco stems powder and PLA. Tobacco particles, with an average size of 50 m, have distribution on the filament. However, clusters of particles, bubbles and porosities were observed in the center of the filament. Fourier Transform Infrared analyses showed that the composite filament presented mechanical interaction between the materials. Thermal analyses allowed to verify that there was no degradation of tobacco stem powder. Therefore, chemical and physical integrity of the composite filament was kept at an extrusion temperature of 180 °C. Differential scanning calorimetry revealed that micronized particles of tobacco stems may have acted as nucleating agents for crystallization, increasing the crystallinity degree of the composite filament. It is recommended for future studies to increase the percentage of tobacco stems powder, the investigation of other methods for composites preparation, as well as a study of the addition of plasticizers or coupling agents to improve the interface between PLA and tobacco particles

Strategic Talent Management: The Impact of Employer Branding on the Affective Commitment of Employees

In a globalization context, underlined by the speed of technological transformation and increasingly competitive markets, the perspective of human capital, as an asset of strategic importance, stands out in di erentiating human resource practices. Under this reality, the employer branding (EB) concept gains more and more importance as a strategic tool to attract, retain, and involve human capital, given that this has become a source of competitive advantage to companies. Within this context, this study aimed to evaluate the relationship between employer branding strategies implemented by organizations, as well as their impact on the employee’s a ective commitment, evident in certain organizational cultures, which are sustained over time. The methodological framework applied to this study is quantitative, and the data collection was carried out with the application of an employer branding and an a ective commitment questionnaire. To achieve a good representation of the active population, the sample of the quantitative study was composed of 172 individuals, working in the public and private sectors in Portugal, exercising di erent positions in the di erent sectors of activity. Results obtained with these techniques indicate a high level of a ective organizational commitment (AOC) of employees in the organizations surveyed, suggesting that a ective commitment develops when the individual becomes involved and identifies with the organization.info:eu-repo/semantics/publishedVersio

AKT can modulate the in vitro response of HNSCC cells to irreversible EGFR inhibitors

Epidermal growth factor receptor (EGFR) is overexpressed in up to 90% of head and neck squamous cell carcinoma (HNSCC) tumors. Cetuximab is the first targeted (anti-EGFR) therapy approved for the treatment of HNSCC patients. However, its efficacy is limited due to primary and secondary resistance, and there is no predict biomarkers of response. New generation of EGFR inhibitors with pan HER targeting and irreversible action, such as afatinib and allitinib, represents a significant therapeutic promise. In this study, we intend to compare the potential cytotoxicity of two anti-EGFR inhibitors (afatinib and allitinib) with cetuximab and to identify potential predictive biomarkers of response in a panel of HNSCC cell lines. The mutational analysis in the eight HNSCC cell lines revealed an EGFR mutation (p.H773Y) and gene amplification in the HN13 cells. According to the growth inhibition score (GI), allitinib was the most cytotoxic drug, followed by afatinib and finally cetuximab. The higher AKT phosphorylation level was associated with resistance to anti-EGFR agents. Therefore, we further performed drug combinations with anti-AKT agent (MK2206) and AKT1 gene editing, which demonstrated afatinib and allitinib sensitivity restored. Additionally, in silico analysis of TCGA database showed that AKT1 overexpression was present in 14.7% (41/279) of HNSCC cases, and was associated with perineural invasion in advanced stage. In conclusion, allitinib presented a greater cytotoxic profile when compared to afatinib and cetuximab. AKT pathway constitutes a predictive marker of allitinib response and combination with AKT inhibitors could restore response and increase treatment success.FINEP (MCTI/FINEP/MS/SCTIE/DECIT-01/2013 - FPXII-BIOPLAT) and the Assistance Program and Incentive Research (PAIP), Barretos Cancer Hospital São Paulo, Brazil. The authors would like to acknowledge the technical support of Gabriela Lamberti in the clonogenic assays. A.L.C and R.M.R are recipients of a National Counsel of Technological and Scientific Development (CNPq) scholarship and O.C.M is recipient of a Portuguese Foundation for Science and Technology (FCT) scholarship (SFRH/BPD/108351/2015)info:eu-repo/semantics/publishedVersio

long-term follow-up (CIMbA-LT)

Funding Information: Collaborators of the CIMBA-LT study: Hospital Vila Franca de Xira: André Oliveira; João Gonçalves-Pereira; Joaquim Lima. Centro Hospitalar de Médio Tejo (Abrantes): Rui Assis; Joana Monteiro. Hospital Nélio Mendonça (Funchal): André Simões; Catarina Lume. Centro Hospitalar de Trás-os-Montes e Alto Douro (Vila Real): Maria João Pinto. Centro Hospitalar de Vila Nova de Gaia: Sara Pipa. Hospital de Braga: Laura Costa. Hospital de Bragança: Cristina Nunes. Hospital do Divino Espírito Santo (S. Miguel): Manuela Henriques; Luís Tavares. Hospital de Leiria: Filipa Sequeira. Centro Hospitalar Universitário de S.João (Porto): José-Artur Paiva; Tatiana Santos Vieira; Núria Jorge. Centro Hospital Universitário de Lisboa Norte (Lisboa): Ana Bento Rodrigues; Susana Fernandes; João Ribeiro. Hospital S.Francisco Xavier (Lisboa): Rui Morais; Pedro Póvoa; Luís Coelho. Centro Hospitalar Universitário de Coimbra: Ana Martinho; Iolanda Santos. Hospital Egas Moniz (Lisboa): Gabriela Almeida. Hospital de Beja: Alexandra Paula; Filipe Morais de Almeida. Centro Hospitalar Universitário do Algarve (Faro): Sofia Ribeiro. Publisher Copyright: © 2023, The Author(s).Background: The past years have witnessed dramatic changes in the population admitted to the intensive care unit (ICU). Older and sicker patients are now commonly treated in this setting due to the newly available sophisticated life support. However, the short- and long-term benefit of this strategy is scarcely studied. Methods: The Critically Ill patients’ mortality by age: Long-Term follow-up (CIMbA-LT) was a multicentric, nationwide, retrospective, observational study addressing short- and long-term prognosis of patients admitted to Portuguese multipurpose ICUs, during 4 years, according to their age and disease severity. Patients were followed for two years after ICU admission. The standardized hospital mortality ratio (SMR) was calculated according to the Simplified Acute Physiology Score (SAPS) II and the follow-up risk, for patients discharged alive from the hospital, according to official demographic national data for age and gender. Survival curves were plotted according to age group. Results: We included 37.118 patients, including 15.8% over 80 years old. The mean SAPS II score was 42.8 ± 19.4. The ICU all-cause mortality was 16.1% and 76% of all patients survive until hospital discharge. The SAPS II score overestimated hospital mortality [SMR at hospital discharge 0.7; 95% confidence interval (CI) 0.63–0.76] but accurately predicted one-year all-cause mortality [1-year SMR 1.01; (95% CI 0.98–1.08)]. Survival curves showed a peak in mortality, during the first 30 days, followed by a much slower survival decline thereafter. Older patients had higher short- and long-term mortality and their hospital SMR was also slightly higher (0.76 vs. 0.69). Patients discharged alive from the hospital had a 1-year relative mortality risk of 6.3; [95% CI 5.8–6.7]. This increased risk was higher for younger patients [21.1; (95% CI 15.1–39.6) vs. 2.4; (95% CI 2.2–2.7) for older patients]. Conclusions: Critically ill patients’ mortality peaked in the first 30 days after ICU admission. Older critically ill patients had higher all-cause mortality, including a higher hospital SMR. A long-term increased relative mortality risk was noted in patients discharged alive from the hospital, but this was more noticeable in younger patients.publishersversionpublishe

Machine learning for predicting fracture strain in sheet metal forming

Machine learning models are built to predict the strain values for which edge cracking occurs in hole expansion tests. The samples from this test play the role of sheet metal components to be manufactured, in which edge cracking often occurs associated with a uniaxial tension stress state at the critical edges of components. For the construction of the models, a dataset was obtained experimentally for rolled ferritic carbon steel sheets of different qualities and thicknesses. Two types of tests were performed: tensile and hole expansion tests. In the tensile test, the yield stress, the tensile strength, the strain at maximum load and the elongation after fracture were determined in the rolling and transverse directions. In the hole expansion test, the strain for which edge cracking occurs, was determined. It is intended that the models can predict the strain at fracture in this test, based on the knowledge of the tensile test data. The machine learning algorithms used were Multilayer Perceptron, Gaussian Processes, Support Vector Regression and Random Forest. The traditional polynomial regression that fits a 2nd order polynomial function was also used for comparison. It is shown that machine learning-based predictive models outperform the traditional polynomial regression method; in particular, Gaussian Processes and Support Vector Regression were found to be the best machine learning algorithms that enable the most robust predictive models.publishe

Freeform 3D printing using a continuous viscoelastic supporting matrix

Embedded bio-printing has fostered significant advances toward the fabrication of soft complex tissue-like constructs, by providing a physical support that allows the freeform shape maintenance within the prescribed spatial arrangement, even under gravity force. Current supporting materials still present major drawbacks for up-scaling embedded 3D bio-printing technology towards tissue-like constructs with clinically relevant dimensions. Herein, we report a a cost-effective and widely available supporting material for embedded bio-printing consisting on a continuous pseudo-plastic matrix of xanthan-gum (XG). This natural polisaccharide exhibits peculiar rheological properties that have enabled the rapid generation of complex volumetric 3D constructs with out of plane features. The freedom of design within the three orthogonal axes through the independent and controlled bio-printing process opens new opportunities to produce on demand large arbitrary shapes for personalized medicine. Additionally, we have demonstrated the versatile functionality of XG as a photocurable gel reservoir to engineer perfused cell-laden hydrogel constructs, addressing other practical biomedical applications such as in vitro models and organ-on-chip platforms.publishe

Formulação e caracterização de potenciais filamentos compósitos de PLA e talos de tabaco para aplicação em manufatura aditiva

A tecnologia de fabricação por filamento fundido (FFF) utilizando polímeros como PLA e ABS é bem conhecida. Contudo, o desenvolvimento de filamentos compósitos para esta tecnologia de manufatura aditiva, bem como a determinação dos parâmetros de processamento e das propriedades resultantes na extrusão e na impressão 3D, ainda requerem pesquisa. Esse estudo exploratório analisa as propriedades químicas, térmicas e a morfologia de filamento de matriz polimérica de PLA e talos de tabaco, visando sua utilização no processo FFF. Os materiais utilizados foram talos de tabaco moídos e PLA. As partículas de tabaco, com tamanho médio de 50 m, apresentaram-se aleatoriamente distribuídas no filamento. No entanto, aglomerados de partículas,  bolhas e porosidades foram observados no centro do filamento. Ensaios por espectroscopia no infravermelho por transformada de Fourier mostraram que o filamento compósito apresentou interação mecânica entre os materiais. A análise térmica permitiu verificar que não houve degradação do pó de talos de tabaco, mantendo a integridade química e física do filamento compósito a temperatura de extrusão de 180 °C. A calorimetria exploratória diferencial revelou que as partículas de pó de talos de tabaco podem ter atuado como agente nucleante, aumentando o grau de cristalinidade do filamento compósito. Sugere-se para estudos futuros o aumento do percentual de pó de talos de tabaco, a investigação de outros métodos de preparação de compósitos, bem como um estudo da adição de plastificantes ou agentes compatibilizantes para aprimorar a ligação entre a interface do PLA e as partículas de tabaco.Palavras-chave: impressão 3D, fabricação de filamento fundido, manufatura aditiva, compósitos, tabaco.