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Given the highly variable clinical phenotype of Coronavirus disease 2019 (COVID-19), a deeper analysis of the host genetic contribution to severe COVID-19 is important to improve our understanding of underlying disease mechanisms. Here, we describe an extended genome-wide association meta-analysis of a well-characterized cohort of 3255 COVID-19 patients with respiratory failure and 12 488 population controls from Italy, Spain, Norway and Germany/Austria, including stratified analyses based on age, sex and disease severity, as well as targeted analyses of chromosome Y haplotypes, the human leukocyte antigen region and the SARS-CoV-2 peptidome. By inversion imputation, we traced a reported association at 17q21.31 to a ~0.9-Mb inversion polymorphism that creates two highly differentiated haplotypes and characterized the potential effects of the inversion in detail. Our data, together with the 5th release of summary statistics from the COVID-19 Host Genetics Initiative including non-Caucasian individuals, also identified a new locus at 19q13.33, including NAPSA, a gene which is expressed primarily in alveolar cells responsible for gas exchange in the lung.
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COVID-19 , Humanos , COVID-19/genética , SARS-CoV-2/genética , Estudio de Asociación del Genoma Completo , Haplotipos , Polimorfismo GenéticoRESUMEN
BACKGROUND: Abnormal remodelling of the extracellular matrix (ECM) has generally been linked to pulmonary inflammation and fibrosis and may also play a role in the pathogenesis of severe COVID-19. To further elucidate the role of ECM remodelling and excessive fibrogenesis in severe COVID-19, we examined circulating levels of mediators involved in various aspects of these processes in COVID-19 patients. METHODS: Serial blood samples were obtained from two cohorts of hospitalised COVID-19 patients (n = 414). Circulating levels of ECM remodelling mediators were quantified by enzyme immunoassays in samples collected during hospitalisation and at 3-month follow-up. Samples were related to disease severity (respiratory failure and/or treatment at the intensive care unit), 60-day total mortality and pulmonary pathology after 3-months. We also evaluated the direct effect of inactivated SARS-CoV-2 on the release of the different ECM mediators in relevant cell lines. RESULTS: Several of the measured markers were associated with adverse outcomes, notably osteopontin (OPN), S100 calcium-binding protein A12 and YKL-40 were associated with disease severity and mortality. High levels of ECM mediators during hospitalisation were associated with computed tomography thorax pathology after 3-months. Some markers (i.e. growth differential factor 15, galectin 3 and matrix metalloproteinase 9) were released from various relevant cell lines (i.e. macrophages and lung cell lines) in vitro after exposure to inactivated SARS-CoV-2 suggesting a direct link between these mediators and the causal agent of COVID-19. CONCLUSION: Our findings highlight changes to ECM remodelling and particularly a possible role of OPN, S100A12 and YKL-40 in the pathogenesis of severe COVID-19.
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COVID-19 , Neumonía , Humanos , COVID-19/metabolismo , Proteína 1 Similar a Quitinasa-3 , SARS-CoV-2 , Matriz ExtracelularRESUMEN
Respiratory failure in the acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic is hypothesized to be driven by an overreacting innate immune response, where the complement system is a key player. In this prospective cohort study of 39 hospitalized coronavirus disease COVID-19 patients, we describe systemic complement activation and its association with development of respiratory failure. Clinical data and biological samples were obtained at admission, days 3 to 5, and days 7 to 10. Respiratory failure was defined as PO2/FiO2 ratio of ≤40 kPa. Complement activation products covering the classical/lectin (C4d), alternative (C3bBbP) and common pathway (C3bc, C5a, and sC5b-9), the lectin pathway recognition molecule MBL, and antibody serology were analyzed by enzyme-immunoassays; viral load by PCR. Controls comprised healthy blood donors. Consistently increased systemic complement activation was observed in the majority of COVID-19 patients during hospital stay. At admission, sC5b-9 and C4d were significantly higher in patients with than without respiratory failure (P = 0.008 and P = 0.034). Logistic regression showed increasing odds of respiratory failure with sC5b-9 (odds ratio 31.9, 95% CI 1.4 to 746, P = 0.03) and need for oxygen therapy with C4d (11.7, 1.1 to 130, P = 0.045). Admission sC5b-9 and C4d correlated significantly to ferritin (r = 0.64, P < 0.001; r = 0.69, P < 0.001). C4d, sC5b-9, and C5a correlated with antiviral antibodies, but not with viral load. Systemic complement activation is associated with respiratory failure in COVID-19 patients and provides a rationale for investigating complement inhibitors in future clinical trials.
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Betacoronavirus/inmunología , Activación de Complemento , Infecciones por Coronavirus/inmunología , Neumonía Viral/inmunología , Insuficiencia Respiratoria/inmunología , Anciano , Biomarcadores/sangre , COVID-19 , Estudios de Casos y Controles , Infecciones por Coronavirus/sangre , Infecciones por Coronavirus/complicaciones , Femenino , Interacciones Huésped-Patógeno/inmunología , Humanos , Masculino , Lectina de Unión a Manosa/sangre , Persona de Mediana Edad , Pandemias , Neumonía Viral/sangre , Neumonía Viral/complicaciones , Insuficiencia Respiratoria/virología , SARS-CoV-2 , Carga ViralRESUMEN
BACKGROUND: Immune dysregulation is a major factor in the development of severe coronavirus disease 2019 (COVID-19). The homeostatic chemokines CCL19 and CCL21 have been implicated as mediators of tissue inflammation, but data on their regulation in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is limited. We thus investigated the levels of these chemokines in COVID-19 patients. METHODS: Serial blood samples were obtained from patients hospitalized with COVID-19 (n = 414). Circulating CCL19 and CCL21 levels during hospitalization and 3-month follow-up were analyzed. In vitro assays and analysis of RNAseq data from public repositories were performed to further explore possible regulatory mechanisms. RESULTS: A consistent increase in circulating levels of CCL19 and CCL21 was observed, with high levels correlating with disease severity measures, including respiratory failure, need for intensive care, and 60-day all-cause mortality. High levels of CCL21 at admission were associated with persisting impairment of pulmonary function at the 3-month follow-up. CONCLUSIONS: Our findings highlight CCL19 and CCL21 as markers of immune dysregulation in COVID-19. This may reflect aberrant regulation triggered by tissue inflammation, as observed in other chronic inflammatory and autoimmune conditions. Determination of the source and regulation of these chemokines and their effects on lung tissue is warranted to further clarify their role in COVID-19. CLINICAL TRIALS REGISTRATION: NCT04321616 and NCT04381819.
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COVID-19 , Humanos , Quimiocina CCL19 , Quimiocina CCL21 , Quimiocinas , Inflamación , Gravedad del Paciente , Receptores CCR7 , SARS-CoV-2RESUMEN
Since the beginning of the pandemic, the transmission modes of SARS-CoV-2-particularly the role of aerosol transmission-have been much debated. Accumulating evidence suggests that SARS-CoV-2 can be transmitted by aerosols, and not only via larger respiratory droplets. In this study, we quantified SARS-CoV-2 in air surrounding 14 test subjects in a controlled setting. All subjects had SARS-CoV-2 infection confirmed by a recent positive PCR test and had mild symptoms when included in the study. RT-PCR and cell culture analyses were performed on air samples collected at distances of one, two, and four meters from test subjects. Oronasopharyngeal samples were taken from consenting test subjects and analyzed by RT-PCR. Additionally, total aerosol particles were quantified during air sampling trials. Air viral concentrations at one-meter distance were significantly correlated with both viral loads in the upper airways, mild coughing, and fever. One sample collected at four-meter distance was RT-PCR positive. No samples were successfully cultured. The results reported here have potential application for SARS-CoV-2 detection and monitoring schemes, and for increasing our understanding of SARS-CoV-2 transmission dynamics. Practical implications. In this study, quantification of SARS-CoV-2 in air was performed around infected persons with mild symptoms. Such persons may go longer before they are diagnosed and may thus be a disproportionately important epidemiological group. By correlating viral concentrations in air with behavior and symptoms, we identify potential risk factors for viral dissemination in indoor environments. We also show that quantification of total aerosol particles is not a useful strategy for monitoring SARS-CoV-2 in indoor environments.
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Microbiología del Aire , Contaminación del Aire Interior , COVID-19 , SARS-CoV-2/aislamiento & purificación , Aerosoles , COVID-19/virología , Humanos , PandemiasRESUMEN
Persisting inflammation has been discovered in lungs and other parenchymatous organs of some COVID-19 convalescents. Calprotectin, neutrophil extracellular traps (NETs), syndecan-1 and neopterin are general key inflammatory markers, and systemically enhanced levels of them may remain after the COVID-19 infection. These inflammatory markers were therefore measured in serum samples of 129 COVID-19 convalescent and 27 healthy blood donors or employees at Oslo Blood bank, Norway. Also antibodies against SARS-CoV-2 nucleocapsid antigen were measured, and timing of sampling and severity of infection noted. Whereas neopterin and NETs values remained low and those for syndecan-1 were not raised to statistically significant level, concentrations for calprotectin, as measured by a novel mixed monoclonal assay, were significantly increased in the convalescents. Antibodies against SARS-CoV-2 nucleocapsid antigen were elevated, but did not correlate with levels of inflammatory markers. Difference between the groups in only one biomarker makes evaluation of ongoing or residual inflammation in the convalescents difficult. If there is a low-grade inflammation, it would in that case involve neutrophils.
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COVID-19 , Trampas Extracelulares , Biomarcadores , Donantes de Sangre , COVID-19/diagnóstico , Humanos , Inflamación/diagnóstico , Complejo de Antígeno L1 de Leucocito , Neopterin , SARS-CoV-2 , Sindecano-1RESUMEN
BACKGROUND: The pathogenesis of coronavirus disease 2019 (COVID-19) is still incompletely understood, but it seems to involve immune activation and immune dysregulation. OBJECTIVE: We examined the parameters of activation of different leukocyte subsets in COVID-19-infected patients in relation to disease severity. METHODS: We analyzed plasma levels of myeloperoxidase (a marker of neutrophil activation), soluble (s) CD25 (sCD25) and soluble T-cell immunoglobulin mucin domain-3 (sTIM-3) (markers of T-cell activation and exhaustion), and sCD14 and sCD163 (markers of monocyte/macrophage activation) in 39 COVID-19-infected patients at hospital admission and 2 additional times during the first 10 days in relation to their need for intensive care unit (ICU) treatment. RESULTS: Our major findings were as follows: (1) severe clinical outcome (ICU treatment) was associated with high plasma levels of sTIM-3 and myeloperoxidase, suggesting activated and potentially exhausted T cells and activated neutrophils, respectively; (2) in contrast, sCD14 and sCD163 showed no association with need for ICU treatment; and (3) levels of sCD25, sTIM-3, and myeloperoxidase were inversely correlated with degree of respiratory failure, as assessed by the ratio of Pao2 to fraction of inspired oxygen, and were positively correlated with the cardiac marker N-terminal pro-B-type natriuretic peptide. CONCLUSION: Our findings suggest that neutrophil activation and, in particular, activated T cells may play an important role in the pathogenesis of COVID-19 infection, suggesting that T-cell-targeted treatment options and downregulation of neutrophil activation could be of importance in this disorder.
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COVID-19/sangre , Receptor 2 Celular del Virus de la Hepatitis A/sangre , SARS-CoV-2/metabolismo , Anciano , Antígenos CD/sangre , Antígenos de Diferenciación Mielomonocítica/sangre , Femenino , Humanos , Subunidad alfa del Receptor de Interleucina-2/sangre , Receptores de Lipopolisacáridos/sangre , Activación de Linfocitos , Masculino , Persona de Mediana Edad , Receptores de Superficie Celular/sangre , Índice de Severidad de la Enfermedad , Linfocitos T/metabolismo , Factores de TiempoRESUMEN
BACKGROUND: The use of complement inhibition is well established for complement mediated thrombotic microangiopathy, but its role in secondary forms of thrombotic microangiopathy is debated. We here present a case of thrombotic microangiopathy triggered by Capnocytophaga canimorsus, illustrating the diagnostic difficulties in discriminating between different thrombotic microangiopathies, and the dilemmas regarding how to treat this disease entity. CASE PRESENTATION: A previously healthy 56-year-old woman presented with fever and confusion. She was diagnosed with sepsis from Capnocytophaga canimorsus and thrombotic microangiopathy. Marked activation of both T-cells, endothelium and complement were documented. She was successfully treated with antimicrobial therapy, the complement inhibitor eculizumab and splenectomy. After several weeks, a heterozygote variant in complement factor B was localized, potentially implying the diagnosis of a complement mediated TMA over an isolated infection related TMA. CONCLUSIONS: We discuss the possible interactions between complement activation and other findings in severe infection and argue that complement inhibition proved beneficial to this patient's rapid recovery.
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Anticuerpos Monoclonales Humanizados/uso terapéutico , Capnocytophaga/patogenicidad , Activación de Complemento , Inactivadores del Complemento/uso terapéutico , Microangiopatías Trombóticas/diagnóstico , Microangiopatías Trombóticas/tratamiento farmacológico , Femenino , Infecciones por Bacterias Gramnegativas , Humanos , Persona de Mediana Edad , Noruega/epidemiología , Sepsis/etiologíaRESUMEN
Objective: We aim to discuss whether preventive quarantine can mitigate the spread of Covid-19 during the pandemic. Design: We did a cross-sectional, observational study design in a mass-screening program in the enrolment to the Norwegian military during April 19-28th 2020 (COVID-NOR-MIL). Subjects: 1170 presumptively healthy young Norwegian conscripts. Setting: A structured interview encouraged the coming conscripts to a self-imposed preventive quarantine the last two weeks before enrolment. Main outcome measures: All conscripts underwent a PCR-based test with nasopharyngeal swabs at the day of enrolment. Results: Only two tested positive. The study discusses the predictive value of the RT-PCR test and the risk of false positive and false negative results, particularly when using the test in a low-prevalent cohort, even if the test properties of sensitivity and specificity is almost 100%. Further, the study discusses the challenge of whether a positive SARS-CoV-2 PCR-test represent viable and contagious virus or only viral remnants. Conclusion: The adherence to self-imposed preventive quarantine is a challenge and is a subject to further research. Implications: We want to draw the attention to the potential value of a thorough pre-screening processes and self-imposed preventive quarantine to minimize the potential spread of SARS-Cov-2.
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COVID-19/prevención & control , Tamizaje Masivo , Personal Militar , Pandemias/prevención & control , Cuarentena , COVID-19/diagnóstico , COVID-19/epidemiología , Prueba de Ácido Nucleico para COVID-19 , Estudios de Cohortes , Estudios Transversales , Humanos , Noruega/epidemiología , Prevalencia , Evaluación de Programas y Proyectos de Salud , SARS-CoV-2/aislamiento & purificación , Sensibilidad y EspecificidadRESUMEN
In late November 2021, an outbreak of Omicron SARS-CoV-2 following a Christmas party with 117 attendees was detected in Oslo, Norway. We observed an attack rate of 74% and most cases developed symptoms. As at 13 December, none have been hospitalised. Most participants were 30-50 years old. Ninety-six percent of them were fully vaccinated. These findings corroborate reports that the Omicron variant may be more transmissible, and that vaccination may be less effective in preventing infection compared with Delta.
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COVID-19 , SARS-CoV-2 , Adulto , Brotes de Enfermedades , Humanos , Persona de Mediana Edad , Noruega/epidemiologíaRESUMEN
BACKGROUND: Testing for SARS-CoV-2 using polymerase chain reaction (PCR) and SARS-CoV-2 antibody tests is a significant part of the effort to combat the COVID-19 pandemic. Mass testing of healthy individuals raises several issues, however, and the results can be challenging to interpret. CASE PRESENTATION: A healthy 19-year-old man entered the military after two weeks of quarantine. The recruit had no respiratory symptoms or fever before, during or after his enrolment, and no history of SARS-CoV-2 exposure. At enrolment, he had a positive rapid test and a venous blood sample showed antibodies against SARS-CoV-2. PCR tests of specimens obtained from the upper respiratory tract were negative at enrolment and at week three, but were positive at week six. INTERPRETATION: The overall assessment of all the tests indicates a probable asymptomatic infection. This case report illustrates the challenge of interpreting screening results in asymptomatic individuals.
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Infecciones Asintomáticas , Prueba de Ácido Nucleico para COVID-19 , Prueba Serológica para COVID-19 , COVID-19/diagnóstico , Humanos , Masculino , Personal Militar , Adulto JovenRESUMEN
BACKGROUND: COVID-19 can cause a fatal outcome in elderly patients, as this case report illustrates. CASE PRESENTATION: An active male in his nineties with a high level of function, despite several severe chronic diseases, was admitted to Oslo University Hospital after two days of fatigue, fever, dyspnoea and dry cough. He scored qSOFA 1 of 3 points due to high respiratory rate, and SIRS 2 of 4 points due to high respiratory rate and fever of 39.4º C. PCR for influenza virus was negative and he received benzylpenicillin for pneumonia. The chest X-ray taken initially showed no lung affection. On day 5 after symptom debut he was tested for COVID-19 which was positive. He had not been travelling to high-risk areas or been exposed to any known confirmed COVID-19 patients. On the same day, a chest CT scan was performed that showed ground-glass opacities. In subsequent days the patient's health rapidly deteriorated. He developed irreversible respiratory failure with hypoxia without hypercapnia despite substantial oxygen support. Chest X-ray taken on disease day 7 showed progression of consolidations. The patient died 9 days after symptom debut. INTERPRETATION: This case illustrates a severe course of COVID-19 with fatal outcome. The patient was also one of the earliest admitted with COVID-19 in a Norwegian hospital and marked a new phase of the epidemic, as he had not been travelling to high-risk areas or been exposed to any confirmed COVID-19 patients.
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Betacoronavirus , Infecciones por Coronavirus , Pandemias , Neumonía Viral , Insuficiencia Respiratoria , Anciano de 80 o más Años , COVID-19 , Infecciones por Coronavirus/complicaciones , Infecciones por Coronavirus/diagnóstico por imagen , Tos/etiología , Notificación de Enfermedades , Resultado Fatal , Fiebre/etiología , Humanos , Masculino , Neumonía Viral/complicaciones , Neumonía Viral/diagnóstico por imagen , Radiografía Torácica , Insuficiencia Respiratoria/etiología , SARS-CoV-2 , Tomografía Computarizada por Rayos XRESUMEN
The role of auditory feedback in vocal production has mainly been investigated by altered auditory feedback (AAF) in real time. In response, speakers compensate by shifting their speech output in the opposite direction. Current theory suggests this is caused by a mismatch between expected and observed feedback. A methodological issue is the difficulty to fully isolate the speaker's hearing so that only AAF is presented to their ears. As a result, participants may be presented with two simultaneous signals. If this is true, an alternative explanation is that responses to AAF depend on the contrast between the manipulated and the non-manipulated feedback. This hypothesis was tested by varying the passive sound attenuation (PSA). Participants vocalized while auditory feedback was unexpectedly pitch shifted. The feedback was played through three pairs of headphones with varying amounts of PSA. The participants' responses were not affected by the different levels of PSA. This suggests that across all three headphones, PSA is either good enough to make the manipulated feedback dominant, or differences in PSA are too small to affect the contribution of non-manipulated feedback. Overall, the results suggest that it is important to realize that non-manipulated auditory feedback could affect responses to AAF.
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Retroalimentación Sensorial/fisiología , Percepción de la Altura Tonal/fisiología , Habla/fisiología , Voz/fisiología , Estimulación Acústica/métodos , Adulto , Femenino , Humanos , Masculino , SonidoRESUMEN
We present an open-source software platform that transforms emotional cues expressed by speech signals using audio effects like pitch shifting, inflection, vibrato, and filtering. The emotional transformations can be applied to any audio file, but can also run in real time, using live input from a microphone, with less than 20-ms latency. We anticipate that this tool will be useful for the study of emotions in psychology and neuroscience, because it enables a high level of control over the acoustical and emotional content of experimental stimuli in a variety of laboratory situations, including real-time social situations. We present here results of a series of validation experiments aiming to position the tool against several methodological requirements: that transformed emotions be recognized at above-chance levels, valid in several languages (French, English, Swedish, and Japanese) and with a naturalness comparable to natural speech.
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Señales (Psicología) , Emociones , Relaciones Interpersonales , Comunicación no Verbal/psicología , Habla , Conducta Verbal , Simulación por Computador , Femenino , Humanos , Lenguaje , Masculino , Percepción del HablaRESUMEN
The pandemic caused by SARS-CoV-2 has created a global humanitarian and economic crisis for which there is currently no solution in sight. Much hope has therefore been pinned on a vaccine that can protect against the disease COVID-19. As of August 2020, the World Health Organization has registered 173 vaccine candidates as being in development. Six candidates have entered phase 3 trials, and the first results from these are expected in the autumn.
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Infecciones por Coronavirus/prevención & control , Pandemias/prevención & control , Neumonía Viral/prevención & control , Vacunas Virales/inmunología , Antígenos Virales/inmunología , Betacoronavirus , COVID-19 , Vacunas contra la COVID-19 , Ensayos Clínicos Fase III como Asunto , Infecciones por Coronavirus/inmunología , Humanos , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus/inmunologíaRESUMEN
Speech is usually assumed to start with a clearly defined preverbal message, which provides a benchmark for self-monitoring and a robust sense of agency for one's utterances. However, an alternative hypothesis states that speakers often have no detailed preview of what they are about to say, and that they instead use auditory feedback to infer the meaning of their words. In the experiment reported here, participants performed a Stroop color-naming task while we covertly manipulated their auditory feedback in real time so that they said one thing but heard themselves saying something else. Under ideal timing conditions, two thirds of these semantic exchanges went undetected by the participants, and in 85% of all nondetected exchanges, the inserted words were experienced as self-produced. These findings indicate that the sense of agency for speech has a strong inferential component, and that auditory feedback of one's own voice acts as a pathway for semantic monitoring, potentially overriding other feedback loops.
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Percepción Auditiva/fisiología , Retroalimentación Sensorial/fisiología , Habla/fisiología , Adulto , Femenino , Humanos , Masculino , Semántica , Percepción del Habla/fisiología , SueciaRESUMEN
OCCUPATIONAL APPLICATIONSIn the context of Industry 5.0, our study advances manufacturing factory layout planning by integrating multi-objective optimization with nature-inspired algorithms and a digital human modeling tool. This approach aims to overcome the limitations of traditional planning methods, which often rely on engineers' expertise and inputs from various functions in a company, leading to slow processes and risk of human errors. By focusing the multi-objective optimization on three primary targets, our methodology promotes objective and efficient layout planning, simultaneously considering worker well-being and system performance efficiency. Illustrated through a pedal car assembly station layout case, we demonstrate how layout planning can transition into a transparent, cross-disciplinary, and automated activity. This methodology provides multi-objective decision support, showcasing a significant step forward in manufacturing factory layout design practices.
Rationale: Integrating multi-objective optimization in manufacturing layout planning addresses simultaneous considerations of productivity, worker well-being, and space efficiency, moving beyond traditional, expert-reliant methods that often overlook critical design aspects. Leveraging nature-inspired algorithms and a digital human modeling tool, this study advances a holistic, automated design process in line with Industry 5.0. Purpose: This research demonstrates an innovative approach to manufacturing layout optimization that simultaneously considers worker well-being and system performance. Utilizing the Non-dominated Sorting Genetic Algorithm II (NSGA-II) and Particle Swarm Optimization (PSO) alongside a Digital Human Modeling (DHM) tool, the study proposes layouts that equally prioritize ergonomic factors, productivity, and area utilization. Methods: Through a pedal car assembly station case, the study illustrates the transition of layout planning into a transparent, cross-disciplinary, and automated process. This method offers objective decision support, balancing diverse objectives concurrently. Results: The optimization results obtained from the NSGA-II and PSO algorithms represent feasible non-dominated solutions of layout proposals, with the NSGA-II algorithm finding a solution superior in all objectives compared to the expert engineer-designed start solution for the layout. This demonstrates the presented method's capacity to refine layout planning practices significantly. Conclusions: The study validates the effectiveness of combining multi-objective optimization with digital human modeling in manufacturing layout planning, aligning with Industry 5.0's emphasis on human-centric processes. It proves that operational efficiency and worker well-being can be simultaneously considered and presents future potential manufacturing design advancements. This approach underscores the necessity of multi-objective consideration for optimal layout achievement, marking a progressive step in meeting modern manufacturing's complex demands.
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Algoritmos , Humanos , Ergonomía/métodos , Industria Manufacturera/métodos , Arquitectura y Construcción de Instituciones de Salud/métodosRESUMEN
Sensory feedback plays an important role in speech motor control. One of the main sources of evidence for this is studies in which online auditory feedback is perturbed during ongoing speech. In motor control, it is therefore crucial to distinguish between sensory feedback and externally generated sensory events. This is called source monitoring. Previous altered feedback studies have taken non-conscious source monitoring for granted, as automatic responses to altered sensory feedback imply that the feedback changes are processed as self-caused. However, the role of conscious source monitoring is unclear. The current study investigated whether conscious source monitoring modulates responses to unexpected pitch changes in auditory feedback. During the first block, some participants spontaneously attributed the pitch shifts to themselves (self-blamers) while others attributed them to an external source (other-blamers). Before Block 2, all participants were informed that the pitch shifts were experimentally induced. The self-blamers then showed a reduction in response magnitude in Block 2 compared with Block 1, while the other-blamers did not. This suggests that conscious source monitoring modulates responses to altered auditory feedback, such that consciously ascribing feedback to oneself leads to larger compensation responses. These results can be accounted for within the dominant comparator framework, where conscious source monitoring could modulate the gain on sensory feedback. Alternatively, the results can be naturally explained from an inferential framework, where conscious knowledge may bias the priors in a Bayesian process to determine the most likely source of a sensory event.