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1.
IEEE Trans Haptics ; 17(2): 277-291, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38277254

RESUMO

Manipulating virtual objects with bare hands is a key interaction in Augmented Reality (AR) applications. However, there are still several limitations that affect the manipulation, including the lack of mutual visual occlusion between virtual and real content as well as the lack of haptic sensations. To address the two abovementioned matters, the role of the visuo-haptic rendering of the hand as sensory feedback is investigated. The first experiment explores the effect of showing the hand of the user as seen by the AR system through an avatar, comparing six visual hand rendering. The second experiment explores the effect of the visuo-haptic hand rendering by comparing two vibrotactile contact techniques provided at four delocalized positions on the hand and combined with the two most representative visual hand renderings from the first experiment. Results show that delocalized vibrotactile haptic hand rendering improved perceived effectiveness, realism, and usefulness when provided close to the contact point. However, the farthest rendering position, i.e., on the contralateral hand, gave the best performance even though it was largely disliked. The visual hand rendering was perceived as less necessary for manipulation when the haptic hand rendering was available, but still provided useful feedback on the hand tracking.


Assuntos
Realidade Aumentada , Mãos , Percepção do Tato , Humanos , Mãos/fisiologia , Percepção do Tato/fisiologia , Feminino , Masculino , Adulto , Adulto Jovem , Retroalimentação Sensorial/fisiologia , Interface Usuário-Computador , Percepção Visual/fisiologia , Realidade Virtual , Vibração , Tato/fisiologia
2.
Chemosphere ; 337: 139384, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37414300

RESUMO

With the recent focus on using advanced water treatment processes for water reuse, interest is growing for utilizing enhanced coagulation to remove dissolved chemical species. Up to 85% of the nitrogen in wastewater effluent is made up of dissolved organic nitrogen (DON), but there is a knowledge gap regarding its removal during coagulation, which can be influenced by DON characteristics. To address this issue, tertiary-treated wastewater samples were analyzed before and after coagulation with polyaluminum chloride and ferric chloride. Samples were size-fractionated into four molecular weight fractions (0.45 µm, 0.1 µm, 10 kDa, and 3 kDa) using vacuum filtration and ultrafiltration. Each fraction was further evaluated by coagulating it separately to assess DON removal during enhanced coagulation. The size fractionated samples were also separated into hydrophilic and hydrophobic fractions using C18 solid phase extraction disks. Fluorescence excitation-emission matrices were used to investigate the characteristics of dissolved organic matter contributing to DON during the coagulation process. The results showed that DON compounds of size <3 kDa constituted a majority of the total DON. Coagulation removed more than 80% DON from size fractions 0.45 µm-0.1 µm and 0.1 µm-10 kDa, but less than 20% was removed from 10 kDa to 3 kDa and <3 kDa fractions. Coagulation on pre-filtered samples removed 19% and 25% of the <3 kDa DON fraction using polyaluminum chloride and ferric chloride, respectively. In all molecular weight fractions, hydrophilic DON compounds were found to be dominant (>90%), and enhanced coagulation was not effective in removing hydrophilic DON compounds. LMW fractions respond poorly to enhanced coagulation due to their hydrophilic nature. Enhanced coagulation effectively removes humic acid-like substances, but poorly removes proteinaceous compounds such as tyrosine and tryptophan. This study's findings provide insights into DON behavior during coagulation and factors affecting its removal, potentially improving wastewater treatment strategies.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Águas Residuárias , Matéria Orgânica Dissolvida , Nitrogênio/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodos
3.
Sci Total Environ ; 877: 162864, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36931510

RESUMO

Most wastewater treatment facilities that satisfy stricter discharge restrictions for nutrients, remove dissolved inorganic nitrogen (DIN) species efficiently, leaving dissolved organic nitrogen (DON) to be present at a higher proportion (up to 85 %) of total nitrogen (TN) in the effluent. Discharged DON promotes algae growth in receiving water bodies and is a growing concern in effluent potable reuse applications considering its potential to form hazardous nitrogenous disinfection byproducts (N-DBPs). Enhanced coagulation is an established process in the advanced water treatment train for most potable reuse applications. However, so far, no information has been collected at the pilot scale to address DON removal efficiency and process implications by enhanced coagulation under real conditions. This study performed a comprehensive evaluation of DON removal from the effluent of the Truckee Meadows Water Reclamation Facility (TMWRF) by enhanced coagulation over the course of 11 months at the pilot scale. Three different coagulants (aluminum sulfate (alum), poly­aluminum chloride (PACl), ferric chloride (FC)) and a cationic polymer coagulant aid (Clarifloc) were used. Optimum doses for each coagulant and polymer and ideal pH were determined by jar tests and applied at the pilot. Alum (24 mg/L) resulted in highly variable DON removal (6 % - 40 %, 21 % on average), which was enhanced by the addition of polymer, leading to 32 % DON removal on average. PACl (40 mg/L) and FC (100 mg/L) resulted in more consistent DON removal (on average 45 % and 57 %, respectively); however, polymer addition exerted minimal enhancement for these coagulants. Overall, enhanced coagulation effectively reduced DON in the tertiary effluent at the pilot scale. The treatment showed auxiliary benefits, including dissolved organic carbon (DOC) and orthophosphate removal.

4.
Rev Mal Respir ; 39(8): 659-668, 2022 Oct.
Artigo em Francês | MEDLINE | ID: mdl-36041937

RESUMO

INTRODUCTION: The goal of the present study is to assess the relationship between functional respiratory parameters measured by the forced oscillation technique (FOT) in COPD patients and (1) dyspnea; (2) inspiratory capacity (IC), along with the variations occurring subsequent to bronchodilation. METHODS: This cross-sectional study analyzed 40 stable COPD patients. Dyspnea was assessed by means of the San Diego Shortness of Breath Questionnaire. Forced oscillations were measured before and after bronchodilation by means of routine pulmonary function tests (PFTs). RESULTS: The reactance parameters measured by the FOT correlated with dyspnea (AX5: r=0.46; P=0.003) similarly to IC (r=-0.46; P=0.003). Changes in AX5 following bronchodilation led to a predicted 12% and 200mL improvement in IC, AX5 (area under the ROC curve=0.85, P<0.001). CONCLUSIONS: Forced oscillation technique (FOT) appears to be an interesting complement to routine PFTs in COPD assessment. Reactance parameters are correlated with dyspnea and their response to bronchodilators is a predictor of significantly improved inspiratory capacity (IC). All in all, FOT may be considered as a functional test with regard to pulmonary hyperinflation, a critical determinant of dyspnea.


Assuntos
Broncodilatadores , Doença Pulmonar Obstrutiva Crônica , Resistência das Vias Respiratórias , Broncodilatadores/farmacologia , Broncodilatadores/uso terapêutico , Estudos Transversais , Dispneia/diagnóstico , Dispneia/etiologia , Volume Expiratório Forçado/fisiologia , Humanos , Oscilometria/métodos , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Testes de Função Respiratória/métodos , Espirometria
5.
IEEE Trans Vis Comput Graph ; 28(2): 1249-1260, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32142442

RESUMO

The goal of Mixed Reality (MR) is to achieve a seamless and realistic blending between real and virtual worlds. This requires the estimation of reflectance properties and lighting characteristics of the real scene. One of the main challenges within this task consists in recovering such properties using a single RGB-D camera. In this article, we introduce a novel framework to recover both the position and color of multiple light sources as well as the specular reflectance of real scene surfaces. This is achieved by detecting and incorporating information from both specular reflections and cast shadows. Our approach is capable of handling any textured surface and considers both static and dynamic light sources. Its effectiveness is demonstrated through a range of applications including visually-consistent mixed reality scenarios (e.g., correct real specularity removal, coherent shadows in terms of shape and intensity) and retexturing where the texture of the scene is altered whereas the incident lighting is preserved.

6.
Respir Res ; 20(1): 237, 2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31665017

RESUMO

BACKGROUND: In the BACE trial, a 3-month (3 m) intervention with azithromycin, initiated at the onset of an infectious COPD exacerbation requiring hospitalization, decreased the rate of a first treatment failure (TF); the composite of treatment intensification (TI), step-up in hospital care (SH) and mortality. OBJECTIVES: (1) To investigate the intervention's effect on recurrent events, and (2) to identify clinical subgroups most likely to benefit, determined from the incidence rate of TF and hospital readmissions. METHODS: Enrolment criteria included the diagnosis of COPD, a smoking history of ≥10 pack-years and ≥ 1 exacerbation in the previous year. Rate ratio (RR) calculations, subgroup analyses and modelling of continuous variables using splines were based on a Poisson regression model, adjusted for exposure time. RESULTS: Azithromycin significantly reduced TF by 24% within 3 m (RR = 0.76, 95%CI:0.59;0.97, p = 0.031) through a 50% reduction in SH (RR = 0.50, 95%CI:0.30;0.81, p = 0.006), which comprised of a 53% reduction in hospital readmissions (RR = 0.47, 95%CI:0.27;0.80; p = 0.007). A significant interaction between the intervention, CRP and blood eosinophil count at hospital admission was found, with azithromycin significantly reducing hospital readmissions in patients with high CRP (> 50 mg/L, RR = 0.18, 95%CI:0.05;0.60, p = 0.005), or low blood eosinophil count (<300cells/µL, RR = 0.33, 95%CI:0.17;0.64, p = 0.001). No differences were observed in treatment response by age, FEV1, CRP or blood eosinophil count in continuous analyses. CONCLUSIONS: This post-hoc analysis of the BACE trial shows that azithromycin initiated at the onset of an infectious COPD exacerbation requiring hospitalization reduces the incidence rate of TF within 3 m by preventing hospital readmissions. In patients with high CRP or low blood eosinophil count at admission this treatment effect was more pronounced, suggesting a potential role for these biomarkers in guiding azithromycin therapy. TRIAL REGISTRATION: ClinicalTrials.gov number. NCT02135354 .


Assuntos
Antibacterianos/uso terapêutico , Azitromicina/uso terapêutico , Progressão da Doença , Readmissão do Paciente/tendências , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Índice de Gravidade de Doença , Idoso , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Falha de Tratamento
7.
BMC Cancer ; 19(1): 639, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31253136

RESUMO

BACKGROUND: To evaluate the outcome of patients treated with stereotactic ablative body radiotherapy (SABR) with curative intent for stage I non-small cell lung cancer (NSCLC) with regard to local, regional and distant tumor control, disease-free survival (DFS), overall survival (OS) and toxicity. METHODS: Data of 300 patients treated with SABR for NSCLC cancer for the period of November 2007 to June 2016 were retrospectively analyzed. Of which, 189 patients had single primary lung lesion and were included in the study. The prescribed dose for the tumor was 48 Gy, given in 12 Gy × 4 fractions for all patients. In 2010, an improved protocol was established in advanced technology for the planning CT, dose calculation and imaging. Cumulative incidence function (CIF) of local, regional, distant or any recurrences were computed using competing risk analysis with death as a competing event. Survivals (DFS and OS) were estimated using the Kaplan-Meier method and Cox proportional regression was used for comparisons. Toxicities were graded according to the common terminology criteria for adverse events version 4.0 (CTCAE v.4). RESULTS: Diagnosis was histologically confirmed in 42% of the patients (N = 80). At 1, 2 and 4 years, the cumulative incidence function (CIF) of local relapses were 8% [4-13%], 15% [10-21%] and 18% [12-25%], the CIF of regional relapses were 4% [2-8%], 10% [6-16%] and 12% [8-19%], the CIF of distant relapses were 9% [5-14%], 15% [11-22%] and 20% [15-28%] and the CIF of any relapses were 14% [10-20%], 28% [22-36%], 34% [27-43%], respectively. After 1, 2 and 4 years, the OS rates were 83% [95% CI: 78-89%] (N = 128), 65% [95% CI: 57-73%] (N = 78) and 37% [95% CI: 29-47%] (N = 53), respectively. The median survival time was 37 months. The DFS after 1, 2 and 4 years reached 75% [95% CI: 68-81%] (N = 114), 49% [95% CI: 42-58%] (N = 60) and 31% [95% CI: 24-41%] (N = 41), respectively. No grade 4 or 5 toxicity was observed. CONCLUSIONS: We observed a long-term local control and survival after SABR for peripheral stage I NSCLC in this large series of patients with the expected low toxicity.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/radioterapia , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Intervalo Livre de Doença , Fracionamento da Dose de Radiação , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Radiocirurgia , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
8.
Am J Respir Crit Care Med ; 200(7): 857-868, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31046405

RESUMO

Rationale: Azithromycin prevents acute exacerbations of chronic obstructive pulmonary disease (AECOPDs); however, its value in the treatment of an AECOPD requiring hospitalization remains to be defined.Objectives: We investigated whether a 3-month intervention with low-dose azithromycin could decrease treatment failure (TF) when initiated at hospital admission and added to standard care.Methods: In an investigator-initiated, multicenter, randomized, double-blind, placebo-controlled trial, patients who had been hospitalized for an AECOPD and had a smoking history of ≥10 pack-years and one or more exacerbations in the previous year were randomized (1:1) within 48 hours of hospital admission to azithromycin or placebo. The study drug (500 mg/d for 3 d) was administered on top of a standardized acute treatment of systemic corticosteroids and antibiotics, and subsequently continued for 3 months (250 mg/2 d). The patients were followed for 6 months thereafter. Time-to-first-event analyses evaluated the TF rate within 3 months as a novel primary endpoint in the intention-to-treat population, with TF defined as the composite of treatment intensification with systemic corticosteroids and/or antibiotics, a step-up in hospital care or readmission for respiratory reasons, or all-cause mortality.Measurements and Main Results: A total of 301 patients were randomized to azithromycin (n = 147) or placebo (n = 154). The TF rate within 3 months was 49% in the azithromycin group and 60% in the placebo group (hazard ratio, 0.73; 95% confidence interval, 0.53-1.01; P = 0.0526). Treatment intensification, step-up in hospital care, and mortality rates within 3 months were 47% versus 60% (P = 0.0272), 13% versus 28% (P = 0.0024), and 2% versus 4% (P = 0.5075) in the azithromycin and placebo groups, respectively. Clinical benefits were lost 6 months after withdrawal.Conclusions: Three months of azithromycin for an infectious AECOPD requiring hospitalization may significantly reduce TF during the highest-risk period. Prolonged treatment seems to be necessary to maintain clinical benefits.


Assuntos
Antibacterianos/uso terapêutico , Azitromicina/uso terapêutico , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Falha de Tratamento , Administração por Inalação , Agonistas Adrenérgicos beta/uso terapêutico , Idoso , Clindamicina/uso terapêutico , Progressão da Doença , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Volume Expiratório Forçado , Glucocorticoides/uso terapêutico , Hospitalização , Humanos , Macrolídeos/uso terapêutico , Masculino , Pessoa de Meia-Idade , Mortalidade , Antagonistas Muscarínicos/uso terapêutico , Readmissão do Paciente , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Quinolonas/uso terapêutico , Capacidade Vital , beta-Lactamas/uso terapêutico
9.
Medicina (Kaunas) ; 55(3)2019 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-30862115

RESUMO

Lung hyperinflation is a main determinant of dyspnoea in patients with chronic obstructive pulmonary disease (COPD). Surgical or bronchoscopic lung volume reduction are the most efficient therapeutic approaches for reducing hyperinflation in selected patients with emphysema. We here report the case of a 69-year old woman with COPD (GOLD stage 3-D) referred for lung volume reduction. She complained of persistent disabling dyspnoea despite appropriate therapy. Chest imaging showed marked emphysema heterogeneity as well as severe hyperinflation of the right lower lobe. She was deemed to be a good candidate for bronchoscopic treatment with one-way endobronchial valves. In the absence of interlobar collateral ventilation, 2 endobronchial valves were placed in the right lower lobe under general anaesthesia. The improvement observed 1 and 3 months after the procedure was such that the patient no longer met the pulmonary function criteria for COPD. The benefit persisted after 3 years.


Assuntos
Pneumonectomia/reabilitação , Próteses e Implantes/efeitos adversos , Implantação de Prótese/efeitos adversos , Implantação de Prótese/reabilitação , Doença Pulmonar Obstrutiva Crônica/diagnóstico por imagem , Doença Pulmonar Obstrutiva Crônica/cirurgia , Atividades Cotidianas , Idoso , Broncoscopia , Dispneia/diagnóstico por imagem , Dispneia/fisiopatologia , Ecocardiografia , Feminino , Seguimentos , Humanos , Hipertensão Pulmonar/diagnóstico por imagem , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Enfisema Pulmonar/diagnóstico por imagem , Enfisema Pulmonar/cirurgia , Testes de Função Respiratória , Fumantes , Tomógrafos Computadorizados , Resultado do Tratamento
10.
Chron Respir Dis ; 16: 1479972318767732, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29631422

RESUMO

Despite overwhelming evidence of its benefits, a widespread implementation of pulmonary rehabilitation (PR) is lacking and the landscape of multidisciplinary programs remains very scattered. The objective of this study is to assess how PR is organized in specialized care centres in Belgium and to identify which barriers may exist according to respiratory physicians. A telephone and online survey was developed by a Belgian expert panel and distributed among all active Belgian chest physicians ( n = 492). Data were obtained from 200 respondents (40%). Seventy-five percentage of the chest physicians had direct access to an ambulatory rehabilitation program in their hospital. Most of these programs are organized bi or triweekly for an average period of 3-6 months. Programs focus strongly on chronic obstructive pulmonary disease patients from secondary care, have a multidisciplinary approach and provide exercise capacity and quality of life measures as main outcomes. Yet large differences were observed in process and outcome indicators between the programs of centres with standard funding and those of specialized centres with a larger allocated budget. We conclude that multidisciplinary PR programs are available in the majority of Belgian hospitals. Differences in funding determine the quality of the team, the diversity of the interventions and the monitoring of outcomes. More resources for rehabilitation will directly improve the utilization and quality of this essential treatment option in respiratory diseases.


Assuntos
Recursos em Saúde , Pneumopatias/fisiopatologia , Pneumopatias/reabilitação , Reabilitação/economia , Bélgica , Tolerância ao Exercício , Humanos , Ambulatório Hospitalar/estatística & dados numéricos , Equipe de Assistência ao Paciente , Pneumologia , Qualidade de Vida , Encaminhamento e Consulta/estatística & dados numéricos , Reabilitação/organização & administração , Inquéritos e Questionários
11.
Int J Chron Obstruct Pulmon Dis ; 13: 3963-3970, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30573956

RESUMO

BACKGROUND: The BODE score (incorporating body mass index, airflow obstruction, dyspnea and exercise capacity) is used for the timing of listing for lung transplantation (LTx) in COPD, based on survival data from the original BODE cohort. This has limitations, because the original BODE cohort differs from COPD patients who are candidates for LTx and the BODE does not include parameters that may influence survival. Our goal was to assess whether parameters such as age, smoking status and diffusion indices significantly influence survival in the absence of LTx, independently of the BODE. METHODS: In the present cohort study, the BODE was prospectively assessed in COPD patients followed in a tertiary care hospital with an LTx program. The files of 469 consecutive patients were reviewed for parameters of interest (age, gender, smoking status and diffusing capacity of the lungs for carbon monoxide [DL,CO]) at the time of BODE assessment, as well as for survival status. Their influence on survival independent of the BODE score was assessed, as well as their ability to predict survival in patients aged less than 65 years. RESULTS: A Cox regression model showed that the BODE score, age and DL,CO were independently related to survival (P-values <0.001), as opposed to smoking status. Survival was better in patients aged less than 65 in the first (P=0.004), third (P=0.002) and fourth BODE quartiles (P=0.008). The difference did not reach significance in the second quartile (P=0.13). Median survival for patients aged less than 65 in the fourth BODE quartile was 55 months. According to a receiver operating characteristic curve analysis, the BODE score as well as FEV1 and DL,CO fared similarly in predicting survival status at 5 years in patients aged less than 65 years. CONCLUSION: Age and DL,CO add to the BODE score to predict survival in COPD. Assessing survival using tools tested in cohorts of patients younger than 65 years is warranted for improving the listing of patients for LTx.


Assuntos
Tomada de Decisão Clínica , Técnicas de Apoio para a Decisão , Transplante de Pulmão , Pulmão/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Listas de Espera , Fatores Etários , Idoso , Resistência das Vias Respiratórias , Índice de Massa Corporal , Dispneia/diagnóstico , Dispneia/fisiopatologia , Tolerância ao Exercício , Feminino , Nível de Saúde , Humanos , Pulmão/cirurgia , Transplante de Pulmão/efeitos adversos , Transplante de Pulmão/mortalidade , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Valor Preditivo dos Testes , Capacidade de Difusão Pulmonar , Doença Pulmonar Obstrutiva Crônica/mortalidade , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/cirurgia , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Fatores Sexuais , Fumar/efeitos adversos , Listas de Espera/mortalidade
14.
Int J Chron Obstruct Pulmon Dis ; 13: 2089-2099, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30013336

RESUMO

Evidence and guidelines are becoming increasingly clear about imbalance between the risks and benefits of inhaled corticosteroids (ICSs) in patients with COPD. While selected patients may benefit from ICS-containing regimens, ICSs are often inappropriately prescribed with - according to Belgian market research data - up to 70% of patients in current practice receiving ICSs, usually as a fixed combination with a long-acting ß2-adrenoreceptor agonist. Studies and recommendations support withdrawal of ICSs in a large group of patients with COPD. However, historical habits appear difficult to change even in the light of recent scientific evidence. We have built a collaborative educational platform with chest physicians and primary care physicians to increase awareness and provide guidance and support in this matter.


Assuntos
Corticosteroides/administração & dosagem , Broncodilatadores/administração & dosagem , Prescrição Inadequada/prevenção & controle , Uso Excessivo de Medicamentos Prescritos/prevenção & controle , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Suspensão de Tratamento , Administração por Inalação , Asma/complicações , Asma/tratamento farmacológico , Quimioterapia Combinada , Humanos , Doença Pulmonar Obstrutiva Crônica/complicações
15.
Front Robot AI ; 5: 93, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-33500972

RESUMO

In this paper we introduce MoSART, a novel approach for Mobile Spatial Augmented Reality on Tangible objects. MoSART is dedicated to mobile interaction with tangible objects in single or collaborative situations. It is based on a novel "all-in-one" Head-Mounted Display (AMD) including a projector (for the SAR display) and cameras (for the scene registration). Equipped with the HMD the user is able to move freely around tangible objects and manipulate them at will. The system tracks the position and orientation of the tangible 3D objects and projects virtual content over them. The tracking is a feature-based stereo optical tracking providing high accuracy and low latency. A projection mapping technique is used for the projection on the tangible objects which can have a complex 3D geometry. Several interaction tools have also been designed to interact with the tangible and augmented content, such as a control panel and a pointer metaphor, which can benefit as well from the MoSART projection mapping and tracking features. The possibilities offered by our novel approach are illustrated in several use cases, in single or collaborative situations, such as for virtual prototyping, training or medical visualization.

16.
Artigo em Inglês | MEDLINE | ID: mdl-28243078

RESUMO

INTRODUCTION: Patients with chronic airway disease may present features of both asthma and COPD, commonly referred to as asthma-COPD overlap syndrome (ACOS). Recommendations on their diagnosis are diffuse and inconsistent. This survey aimed to identify consensus on criteria for diagnosing ACOS. METHODS: A Belgian expert panel developed a survey on ACOS diagnosis, which was completed by 87 pulmonologists. Answers chosen by ≥70% of survey respondents were considered as useful criteria for ACOS diagnosis. The two most frequently selected answers were considered as major criteria, others as minor criteria. The expert panel proposed a minimal requirement of two major criteria and one minor criterion for ACOS diagnosis. Respondents were also asked which criteria are important for considering inhaled corticosteroids prescription in a COPD patient. RESULTS: To diagnose ACOS in COPD patients, major criteria were "high degree of variability in airway obstruction over time (change in forced expiratory volume in 1 second ≥400 mL)" and "high degree of response to bronchodilators (>200 mL and ≥12% predicted above baseline)". Minor criteria were "personal/family history of atopy and/or IgE sensitivity to ≥1 airborne allergen", "elevated blood/sputum eosinophil levels and/or increased fractional exhaled nitric oxide", "diagnosis of asthma <40 years of age"; "symptom variability", and "age (in favor of asthma)". To diagnose ACOS in asthma patients, major criteria were "persistence of airflow obstruction over time (forced expiratory volume in 1 second/forced vital capacity ratio <0.7)" and "exposure to noxious particles/gases, with ≥10 pack-years for (ex-)smokers"; minor criteria were "lack of response on acute bronchodilator test"; "reduced diffusion capacity"; "limited variability in airway obstruction"; "age >40 years"; "emphysema on chest computed tomography scan". CONCLUSION: Specific criteria were identified that may guide physicians to a more uniform diagnostic approach for ACOS in COPD or asthma patients. These criteria are largely similar to those used to prescribe inhaled corticosteroids in COPD.


Assuntos
Asma/diagnóstico , Técnicas de Apoio para a Decisão , Pulmão/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Pneumologistas , Testes de Função Respiratória , Inquéritos e Questionários , Administração por Inalação , Asma/tratamento farmacológico , Asma/epidemiologia , Asma/fisiopatologia , Bélgica/epidemiologia , Broncodilatadores/administração & dosagem , Consenso , Feminino , Volume Expiratório Forçado , Inquéritos Epidemiológicos , Humanos , Pulmão/efeitos dos fármacos , Masculino , Valor Preditivo dos Testes , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Síndrome , Capacidade Vital
17.
Med Image Anal ; 35: 582-598, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27689897

RESUMO

In this paper, we present a real-time approach that allows tracking deformable structures in 3D ultrasound sequences. Our method consists in obtaining the target displacements by combining robust dense motion estimation and mechanical model simulation. We perform evaluation of our method through simulated data, phantom data, and real-data. Results demonstrate that this novel approach has the advantage of providing correct motion estimation regarding different ultrasound shortcomings including speckle noise, large shadows and ultrasound gain variation. Furthermore, we show the good performance of our method with respect to state-of-the-art techniques by testing on the 3D databases provided by MICCAI CLUST'14 and CLUST'15 challenges.


Assuntos
Imageamento Tridimensional/métodos , Ultrassonografia/métodos , Algoritmos , Simulação por Computador , Bases de Dados Factuais , Imagens de Fantasmas , Reprodutibilidade dos Testes
18.
IEEE Trans Vis Comput Graph ; 22(12): 2633-2651, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-26731768

RESUMO

Augmented reality (AR) allows to seamlessly insert virtual objects in an image sequence. In order to accomplish this goal, it is important that synthetic elements are rendered and aligned in the scene in an accurate and visually acceptable way. The solution of this problem can be related to a pose estimation or, equivalently, a camera localization process. This paper aims at presenting a brief but almost self-contented introduction to the most important approaches dedicated to vision-based camera localization along with a survey of several extension proposed in the recent years. For most of the presented approaches, we also provide links to code of short examples. This should allow readers to easily bridge the gap between theoretical aspects and practical implementations.

19.
Environ Toxicol Chem ; 34(7): 1472-84, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25727029

RESUMO

Trenbolone acetate metabolites are endocrine-active contaminants discharged into the aquatic environment in runoff from agricultural fields, rangelands, and concentrated animal feeding operations. To investigate the environmental fate of these compounds and their biotransformation mechanisms, the authors used inocula from a variety of different water sources and dosed biologically active microcosms with approximately 1400 ng/L of trenbolone acetate metabolites, including 17ß-trenbolone, trendione, and 17α-trenbolone. To investigate aerobic biotransformation rates and interconversions between known trenbolone acetate metabolites, gas chromatography-tandem mass spectrometry was used to measure concentrations and assess product distributions as a function of time. High-resolution liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to characterize novel transformation products and potential transformation pathways. Kinetic analysis yields observed half-lives of approximately 0.9 d, 1.3 d, and 2.2 d for 17ß-trenbolone, trendione, and 17α-trenbolone, respectively, at 20 °C, although colder conditions increased half-lives to 8.5 d and biphasic transformation was observed. Relative to reported faster attenuation rates in soils, trenbolone acetate metabolites are likely more persistent in aqueous systems. Product distributions indicate an enzymatic preference for biotransformation between trendione and 17ß-trenbolone. The LC-MS/MS characterization indicates dehydrogenation products as the major detectable products and demonstrates that major structural elements responsible for bioactivity in steroids are likely retained during biotransformation.


Assuntos
Anabolizantes/metabolismo , Espectrometria de Massas em Tandem , Acetato de Trembolona/análise , Poluentes Químicos da Água/análise , Anabolizantes/análise , Ração Animal , Animais , Biodegradação Ambiental , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , Meia-Vida , Concentração de Íons de Hidrogênio , Cinética , Temperatura , Acetato de Trembolona/metabolismo , Poluentes Químicos da Água/metabolismo
20.
J Med Imaging Radiat Oncol ; 59(1): 134-6, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25565562

RESUMO

Familial cerebral cavernous malformations are autosomal dominant conditions that can result in significant morbidity. A two-hit mechanism is accepted as likely responsible for formation of these malformations. We present two patients with this disease who received therapeutic radiation and developed very high numbers of malformations within the radiation ports, supporting radiation as an accelerator of lesion formation and suggesting implications for risks of radiation in this disease.


Assuntos
Encéfalo/patologia , Hemangioma Cavernoso do Sistema Nervoso Central/etiologia , Hemangioma Cavernoso do Sistema Nervoso Central/radioterapia , Radioterapia Conformacional/efeitos adversos , Feminino , Hemangioma Cavernoso do Sistema Nervoso Central/genética , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
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