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1.
Waste Manag Res ; 42(2): 126-134, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37313960

RESUMO

Despite many years of experience in the incineration of solid fuels from waste, the heterogeneity of solid fuels and their varying properties still pose a challenge for a stable and clean combustion in large-scale incineration plants. In modern facilities such as municipal waste incineration plants there still exists a lack of knowledge on the exact amount and calorific value of waste entering onto the grate. Based on the works of Warnecke et al. and Zwiellehner et al., in our project 'AdOnFuelControl', we determined the initial bulk density at the feed hopper by measuring the weight of the waste via the crane weigher and the volume via a high-performance 3D laser scanner. With the help of the determined bulk density, the lower heating value (LHV) and the compression in the feed hopper were calculated. All this information was integrated into the combustion control system, which provided a high potential for an optimized operation of the plant. In this article, six different fuels (fresh and aged municipal solid waste, refuse-derived fuel (fluff), refuse-derived fuel (fine grain), waste wood and dried, grained sewage sludge) were examined for the elemental composition, the LHV, fuel-specific parameters and the compression behaviour. In addition, initial tests with the 3D laser scanner as well as formulas for the calculation of the density in the feed hopper were presented. Based on the results of the experiments, the chosen approach seems very promising for optimized combustion control in large-scale incineration plants. As a next step, the gained knowledge and technology should be integrated in the municipal waste incineration plant.


Assuntos
Incineração , Resíduos Sólidos , Incineração/métodos , Resíduos Sólidos/análise , Esgotos
2.
BMC Gastroenterol ; 22(1): 53, 2022 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-35130851

RESUMO

BACKGROUND: Congenital portosystemic shunts (CPSS) are rare vascular malformations and can be classified into extrahepatic and intrahepatic shunts. Extrahepatic CPSS, also termed Abernethy malformations are associated with severe long-term complications including portopulmonary hypertension, liver atrophy, hyperammoniemia and hepatic encephalopathy. We report a hitherto undescribed variant of Abernethy malformation requiring an innovative approach for interventional treatment. CASE PRESENTATION: We describe a 31-year-old patient following surgical repair of atrioventricular septal defect at the age of 6 years. In the long-term follow-up he showed persistent pulmonary hypertension which deteriorated despite dual pulmonary vasodilative treatment. When he developed arterial desaturation and symptomatic hyperammoniemia detailed reassessment revealed as underlying cause a hitherto undescribed variant of Abernethy malformation connecting the portal vein with the right lower pulmonary vein. Following interdisciplinary discussions we opted for an interventional approach. Since the malformation was un-accessible to interventional closure via antegrade venous or retrograde arterial access, a transhepatic percutaneous puncture of the portal vein was performed. Temporary balloon occlusion of the malformation revealed only a slight increase in portal venous pressure. Interventional occlusion of the large vascular connection was achieved via this transhepatic approach by successive implantation of two large vascular occluding devices. The postinterventional course was unremarkable and both ammonia levels and arterial saturation normalized at follow-up of 12 months. CONCLUSIONS: Portal vein anomalies should be included in the differential diagnoses of pulmonary hypertension or pulmonary arterio-venous malformations. Based on careful assessment of the anatomy and testing of portal vein hemodynamics interventional therapy of complex Abernethy malformations can be performed successfully in specialized centers.


Assuntos
Encefalopatia Hepática , Malformações Vasculares , Adulto , Criança , Humanos , Masculino , Pressão na Veia Porta , Veia Porta/cirurgia , Derivação Portossistêmica Cirúrgica , Malformações Vasculares/complicações
3.
Pediatr Cardiol ; 43(1): 8-16, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34363499

RESUMO

One of the major obstacles preventing successful percutaneous pulmonary valve implantation (PPVI) is related to the close proximity of coronary artery branches to the expected landing zone. The aim of this study was to assess the frequency of coronary artery anomalies (CAAs) especially those associated with major coronary branches crossing the right ventricular outflow tract (RVOT) and to describe their relevance for the feasibility of percutaneous pulmonary valve implantation (PPVI). In our retrospective single-center study 90 patients were evaluated who underwent invasive testing for PPVI in our institution from 1/2010 to 1/2020. CAAs were identified in seven patients (8%) associated with major branches crossing the RVOT due to origin of the left anterior descending (LAD) or a single coronary artery from the right aortic sinus. In 5/7 patients with CAAs balloon testing of the RVOT and selective coronary angiographies revealed a sufficiently large landing zone distal to the coronary artery branch. While unfavorable RVOT dimensions prevented PPVI in one, PPVI was performed successfully in the remaining four patients. The relatively short landing zone required application of the "folded" melody technique in two patients. All patients are doing well (mean follow-up 3 years). CAAs associated with major coronary branches crossing the RVOT can be expected in about 8% of patients who are potential candidates for PPVI. Since the LAD crossed the RVOT below the plane of the pulmonary valve successful distal implantation of the valve was possible in 4/7 patients. Therefore these coronary anomalies should not be considered as primary contraindications for PPVI.


Assuntos
Implante de Prótese de Valva Cardíaca , Próteses Valvulares Cardíacas , Insuficiência da Valva Pulmonar , Valva Pulmonar , Cateterismo Cardíaco , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/cirurgia , Estudos de Viabilidade , Humanos , Valva Pulmonar/diagnóstico por imagem , Valva Pulmonar/cirurgia , Insuficiência da Valva Pulmonar/cirurgia , Estudos Retrospectivos , Resultado do Tratamento
4.
Thorac Cardiovasc Surg ; 69(S 03): e32-e40, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33851400

RESUMO

BACKGROUND: Long-term course after atrial switch operation is determined by increasing right ventricular (RV) insufficiency. The aim of our study was to investigate subtle functional parameters by invasive measurements with conductance technique and noninvasive examinations with cardiac magnetic resonance imaging (CMR). METHODS: We used invasive (pressure-volume loops under baseline conditions and dobutamine) and noninvasive techniques (CMR with feature tracking [FT] method) to evaluate RV function. All patients had cardiopulmonary exercise testing (CPET). RESULTS: From 2011 to 2013, 16 patients aged 28.2 ± 7.3 (22-50) years after atrial switch surgery (87.5% Senning and 12.5% Mustard) were enrolled in this prospective study. All patients were in New York Heart Association (NYHA) class I to II and presented mean peak oxygen consumption of 30.1 ± 5.7 (22.7-45.5) mL/kg/min. CMR-derived end-diastolic volume was 110 ± 22 (78-156) mL/m2 and RV ejection fraction 41 ± 8% (25-52%). CMR-FT revealed lower global systolic longitudinal, radial, and circumferential strain for the systemic RV compared with the subpulmonary left ventricle. End-systolic elastance (Ees) was overall reduced (compared with data from the literature) and showed significant increase under dobutamine (0.80 ± 0.44 to 1.89 ± 0.72 mm Hg/mL, p ≤ 0.001), whereas end-diastolic elastance (Eed) was not significantly influenced (0.11 ± 0.70 to 0.13 ± 0.15 mm Hg/mL, p = 0.454). We found no relevant relationship between load-independent conductance indices and strain or CPET parameters. Conductance analysis revealed significant mechanical dyssynchrony, higher during diastole (mean 30 ± 4% baseline, 24 ± 6% dobutamine) than during systole (mean 17 ± 6% baseline, 19 ± 7% dobutamine). CONCLUSIONS: Functional assessment of a deteriorating systemic RV remains demanding. Conductance indices as well as the CMR-derived strain parameters showed overall reduced values, but a significant relationship was not present (including CPET). Our conductance analysis revealed intraventricular and predominantly diastolic RV dyssynchrony.


Assuntos
Transposição das Grandes Artérias/efeitos adversos , Cateterismo Cardíaco , Imageamento por Ressonância Magnética , Transposição dos Grandes Vasos/cirurgia , Disfunção Ventricular Direita/diagnóstico , Função Ventricular Direita , Pressão Ventricular , Adulto , Estudos Transversais , Teste de Esforço , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Fatores de Tempo , Resultado do Tratamento , Disfunção Ventricular Direita/etiologia , Disfunção Ventricular Direita/fisiopatologia , Adulto Jovem
5.
BMC Pediatr ; 20(1): 132, 2020 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-32293361

RESUMO

BACKGROUND: Anomalous aortic origin of the left coronary artery (AAOLCA) from the right aortic sinus is a rare congenital anomaly associated with significantly increased risk of myocardial ischemia, arrhythmias and sudden cardiac death. This refers specifically to AAOLCA associated with interarterial and/or intramural course. Much less is known about anomalous origin of the left coronary artery from the right aortic sinus associated with a subpulmonic intramyocardial course. CASE PRESENTATION: We report a 12 year old girl who complained of recurrent episodes of chest pain lasting for some minutes and not associated to exercise. Echocardiography revealed AAOLCA from the right aortic sinus taking a subpulmonic course within the conal septum. The diagnosis was confirmed by CT-scan and selective coronary angiography. Treadmill test, Holter-ECG and bicycle-stress echocardiography revealed no evidence of myocardial ischemia reflecting unimpaired diastolic flow in the left coronary artery. According to the nature of the complaints and in the absence of signs of myocardial ischemia the episodes of chest pain were classified as idiopathic and not associated to the coronary anomaly. We opted for a conservative approach with regular follow-up visits. During a follow-up of 2 years without restriction of sports activities the patient has been asymptomatic. CONCLUSION: According to the literature AAOLCA with subpulmonary intramyocardial course appears to be associated with significantly less clinical problems than AAOLCA taking an interarterial course. The diagnosis can be suspected based on echocardiography and confirmed by contrast-enhanced computed tomography. Until now there are only few data concerning the natural history and incidence of complications in this specific anomaly. Despite the probably benign nature we recommend regular follow-up examinations including stress-testing in these patients.


Assuntos
Anomalias dos Vasos Coronários , Seio Aórtico , Criança , Anomalias dos Vasos Coronários/diagnóstico por imagem , Feminino , Humanos , Estudos Prospectivos
6.
Thorac Cardiovasc Surg ; 67(1): 50-54, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29772586

RESUMO

BACKGROUND: Post-coarctation of the aorta (CoA) pseudoaneurysms is a complication of open repair. Thoracic endovascular repair (TEVAR) is feasible but complicated by proximity to the supra-aortic trunks and severe arch angulation. METHODS: We describe three cases of post-CoA pseudoaneurysms treated with custom-made Relay stent grafts (Vascutek, Scotland). RESULTS: Technical and clinical success was achieved in all three cases with no mortality, morbidity, endoleaks, or complications. In all three, pseudoaneurysm sac shrinkage was observed at the follow-ups; in one case, there was complete resolution. CONCLUSION: Redo open surgery is challenging because of adhesions of the thoracic cavity and associated morbidity and mortality. TEVAR is less invasive and offers fewer complications. Custom-made modifications overcome difficult anatomies including short landing zones and diameter variability.


Assuntos
Falso Aneurisma/cirurgia , Aneurisma da Aorta Torácica/cirurgia , Coartação Aórtica/cirurgia , Implante de Prótese Vascular/instrumentação , Prótese Vascular , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Procedimentos Endovasculares/instrumentação , Stents , Adulto , Falso Aneurisma/diagnóstico por imagem , Falso Aneurisma/etiologia , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/etiologia , Coartação Aórtica/diagnóstico por imagem , Aortografia/métodos , Humanos , Masculino , Desenho de Prótese , Tomografia Computadorizada por Raios X , Resultado do Tratamento
7.
Waste Manag Res ; 37(10): 1033-1042, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31345141

RESUMO

The market for products containing engineered nanomaterial (ENM) is constantly expanding. At the end of their lifecycle, a significant fraction of the products will be disposed as ENM-containing waste in thermal treatment plants. Up to now there are still uncertainties on the fate and behaviour of ENM during waste incineration. In our investigations, nano titanium dioxide (nTiO2) was selected as an example for ENM, because of its high amount in consumer products and its relevance to the ENM-containing waste stream. Two test series were conducted at the municipal solid waste incineration plant "Gemeinschaftskraftwerk Schweinfurt". For each test series, background concentrations of titanium were measured first. Samples of bottom ash, bottom ash extractor water, fly ash (boiler ash, cyclone ash), flue gas cleaning products (spray absorber ash, fabric filter ash) and washing water from the wet scrubber were taken in order to determine the fate of nTiO2. The flue gas was sampled at three points: after boiler, after cyclone and before stack. The experiments showed that most of the used reference material was located in the solid residues (i.e. bottom ash) while a smaller part was detected in the products of the flue gas cleaning. In the purified flue gas before the stack, the concentration was negligible. The flue gas cleaning system at the Gemeinschaftskraftwerk Schweinfurt complies with the requirements of the best available techniques and the results cannot be transferred to plants with lower standards.


Assuntos
Incineração , Nanoestruturas , Cinza de Carvão , Resíduos Sólidos , Titânio
8.
Pediatr Cardiol ; 39(4): 810-817, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29396582

RESUMO

There are many complex cardiac malformations that are characterized by a functionally univentricular physiology. Staged surgical repair according to the Fontan principle separates the systemic and pulmonary circulations by connecting the systemic venous return to the pulmonary arteries. However, long-term follow-up studies demonstrate a gradual deterioration of cardiac function, particularly from the second or third decade. Noninvasive evaluation of the cardiac function is, therefore, important in the follow-up of these patients. The cardiac index (CI) is a reliable hemodynamic parameter and represents an important marker of cardiac function. We compared CI values determined by cardiac MRI (CMRI) with values obtained by noninvasive inert gas rebreathing (IGR; Innocor® system). Sixteen patients (age range: 7.2-32.7 years) with functionally univentricular hearts (UVH) following total cavopulmonary connection (TCPC) were compared with 12 healthy subjects (age range: 8.5-18.6 years). The standard treadmill protocol of the German Society of Pediatric Cardiology was used for exercise testing. CI was determined at rest and at two standardized submaximal exercise levels. In all subjects, CI increased under exercise conditions, but the values were significantly lower in patients with UVH. There was no significant difference between patients with UVH and predominantly right- or left-ventricular morphology. In comparison with CMRI measurements, the CI values obtained by the IGR method tended to be lower, with a mean difference of 1.02 l/min/m2. Noninvasive measurement of CI with the IGR method is feasible at rest and during exercise, and appears to be suited for routine determination of CI in patients with UVH following TCPC.


Assuntos
Débito Cardíaco/fisiologia , Teste de Esforço/métodos , Cardiopatias Congênitas/fisiopatologia , Imagem Cinética por Ressonância Magnética/métodos , Gases Nobres/administração & dosagem , Adolescente , Adulto , Criança , Exercício Físico/fisiologia , Tolerância ao Exercício/fisiologia , Estudos de Viabilidade , Feminino , Técnica de Fontan/métodos , Cardiopatias Congênitas/diagnóstico por imagem , Humanos , Masculino , Estudos Retrospectivos , Espirometria/métodos , Adulto Jovem
9.
Environ Sci Technol ; 51(11): 6580-6589, 2017 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-28437609

RESUMO

Water-soluble organic compounds (WSOCs) were extracted from corn stalk biochar produced at increasing pyrolysis temperatures (350-650 °C) and from the corresponding vapors, collected as bio-oil. WSOCs were characterized by gas chromatography (semivolatile fraction), negative electron spray ionization high resolution mass spectrometry (hydrophilic fraction) and fluorescence spectroscopy. The pattern of semivolatile WSOCs in bio-oil was dominated by aromatic products from lignocellulose, while in biochar was featured by saturated carboxylic acids from hemi/cellulose and lipids with concentrations decreasing with decreasing H/C ratios. Hydrophilic species in poorly carbonized biochar resembled those in bio-oil, but the increasing charring intensity caused a marked reduction in the molecular complexity and degree of aromaticity. Differences in the fluorescence spectra were attributed to the predominance of fulvic acid-like structures in biochar and lignin-like moieties in bio-oil. The divergence between pyrolysis vapors and biochar in the distribution of WSOCs with increasing carbonization was explained by the hydrophobic carbonaceous matrix acting like a filter favoring the release into water of carboxylic and fulvic acid-like components. The formation of these structures was confirmed in biochar produced by pilot plant pyrolysis units. Biochar affected differently shoot and root length of cress seedlings in germination tests highlighting its complex role on plant growth.


Assuntos
Carvão Vegetal , Água , Cromatografia Gasosa-Espectrometria de Massas , Compostos Orgânicos
11.
Pediatr Radiol ; 45(10): 1448-54, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25903840

RESUMO

BACKGROUND: Newborns and small infants have shallow breathing. OBJECTIVE: To suggest criteria for when respiratory gating is necessary during cardiac MRI in newborns and infants. MATERIALS AND METHODS: One-hundred ten data sets of newborns and infants with (n = 92, mean age: 1.9 ± 1.7 [SD] years) and without (n = 18, mean age: 1.6 ± 1.8 [SD] years) navigator gating were analysed retrospectively. The respiratory motion of the right hemidiaphragm was recorded and correlated to age, weight, body surface area and qualitative image quality on a 4-point score. Quantitative image quality assessment was performed (sharpness of the delineation of the ventricular septal wall) as well as a matched-pair comparison between navigator-gated and non-gated data sets. RESULTS: No significant differences were found in overall image quality or in the sharpness of the ventricular septal wall between gated and non-gated scans. A navigator acceptance of >80% was frequently found in patients ages <12 months, body surface area <0.40 m(2), body weight <10 kg and a size of <80 cm. CONCLUSION: Sequences without respiratory gating may be used in newborns and small infants, in particular if age <12 months, body surface area <0.40 m(2), body weight <10 kg and height <80 cm.


Assuntos
Cardiopatias Congênitas/diagnóstico , Interpretação de Imagem Assistida por Computador , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Miocárdio/patologia , Artefatos , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Respiração , Estudos Retrospectivos
13.
JAMA Cardiol ; 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39320884

RESUMO

Importance: The ability to predict sudden cardiac death (SCD) in children and adolescents with hypertrophic cardiomyopathy (HCM) is currently inadequate. Late gadolinium enhancement (LGE) by cardiovascular magnetic resonance (CMR) imaging is associated with SCD events in adults with HCM. Objective: To examine the prognostic significance of LGE in patients with HCM who are younger than 21 years. Design, Setting, and Participants: This multicenter, retrospective cohort study was conducted from April 8, 2015, to September 12, 2022, in patients with HCM who were younger than 21 years and had undergone CMR imaging across multiple sites in the US, Europe, and South America. Observers of CMR studies were masked toward outcomes and demographic characteristics. Exposure: Natural history of HCM. Main Outcome and Measures: The primary outcome was SCD and surrogate events, including resuscitated cardiac arrest and appropriate discharges from an implantable defibrillator. Continuous and categorical data are expressed as mean (SD), median (IQR), or number (percentage), respectively. Survivor curves comparing patients with and without LGE were constructed by the Kaplan-Meier method, and likelihood of subsequent clinical events was further evaluated using univariate and multivariable Cox proportional hazards models. Results: Among 700 patients from 37 international centers, median (IQR) age was 14.8 (11.9-17.4) years, and 518 participants (74.0%) were male. During a median (IQR) [range] follow-up period of 1.9 (0.5-4.1) [0.1-14.8] years, 35 patients (5.0%) experienced SCD or equivalent events. LGE was present in 230 patients (32.9%), which constituted an mean (SD) burden of 5.9% (7.3%) of left ventricular myocardium. The LGE amount was higher in older patients and those with greater left ventricular mass and maximal wall thickness; patients with LGE had lower left ventricular ejection fractions and larger left atrial diameters. The presence and burden of LGE was associated with SCD, even after correcting for existing risk stratification tools. Patients with 10% or more LGE, relative to total myocardium, had a higher risk of SCD (unadjusted hazard ratio [HR], 2.19; 95% CI, 1.59-3.02; P < .001). Furthermore, the addition of LGE burden improved the performance of the HCM Risk-Kids score (before LGE addition: 0.66; 95% CI, 0.58-0.75; after LGE addition: 0.73; 95% CI, 0.66-0.81) and Precision Medicine in Cardiomyopathy score (before LGE addition: 0.68; 95% CI, 0.49-0.77; after LGE addition: 0.73; 95% CI, 0.64-0.82) SCD predictive models. Conclusions and Relevance: In this retrospective cohort study, quantitative LGE was a risk factor for SCD in patients younger than 21 years with HCM and improved risk stratification.

14.
Front Cardiovasc Med ; 10: 1145613, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37229222

RESUMO

Objectives: In this study we examined the correlation between the extent of thoracic lymphatic anomalies in patients after surgical palliation by total cavopulmonary connection (TCPC) and their outcome in terms of clinical and laboratory parameters. Materials and methods: We prospectively examined 33 patients after TCPC with an isotropic heavily T2-weighted MRI sequence on a 3.0 T scanner. Examinations were performed after a solid meal, slice thickness of 0.6 mm, TR of 2400 ms, TE of 692 ms, FoV of 460 mm, covering thoracic and abdominal regions. Findings of the lymphatic system were correlated with clinical and laboratory parameters obtained at the annual routine check-up. Results: Eight patients (group 1) showed type 4 lymphatic abnormalities. Twentyfive patients (group 2) presented less severe anomalies (type 1-3). In the treadmill CPET, group 2 reached step 7.0;6.0/8.0 vs. 6.0;3.5/6.8 in group 1 (p = 0.006*) and a distance of 775;638/854 m vs. 513;315/661 m (p = 0.006*). In the laboratory examinations, group 2 showed significantly lower levels of AST, ALT and stool calprotectin as compared to group 1. There were no significant differences in NT-pro-BNP, total protein, IgG, lymphocytes or platelets, but trends. A history of ascites showed 5/8 patients in group 1 vs. 4/25 patients in group 2 (p = 0.02*), PLE occurred in 4/8 patient in group 1 vs. 1/25 patients in group 2 (p = 0.008*). Conclusion: In the long-term follow-up after TCPC, patients with severe thoracic and cervical lymphatic abnormalities showed restrictions in exercise capacity, higher liver enzymes and an increased rate of symptoms of imminent Fontan-failure such as ascites and PLE.

16.
Acad Radiol ; 28 Suppl 1: S218-S224, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33183951

RESUMO

RATIONALE AND OBJECTIVES: The aim of this study was to assess the potential benefit of a high-fat meal for preparation of patients before lymphangiography of the thoracic and abdominal lymphatic vessels by a heavily T2-weighted 3D magnetic resonance sequence at 3T. MATERIALS AND METHODS: A heavily T2-weighted 3D Fast-Spin-Echo sequence was applied twice for lymphangiography in 15 healthy volunteers. One examination was performed following overnight fasting and the second examination was conducted 3 hours after a drinking of 200 ml of cream and a solid meal. The effect of a high-fat meal on the visualization of different segments of the thoracic and abdominal lymphatic vessels was analyzed by scoring of the image quality. RESULTS: Evaluation of the summarized score of all four segments of the thoracic duct showed significantly improved general visualization of the lymphatic system in the postprandial examination when compared to the results obtained after overnight fasting (mean ± SD: 4.5 ± 1.7 vs. 5.9 ± 1.8, p = 0.007*). Regarding different segments of the lymphatic system significant differences between pre and post cream lymphangiographies were found in the cervical segment (p = 0.012*), the inferior thoracic segment (p = 0.003*) and the abdominal segment (p = 0.035*). In contrast, the visualization of the superior thoracic segment was not significantly improved by high fat meal preparation of the subjects (p = 0.388). CONCLUSION: A high-fat meal 3 hours prior to T2-weighted MR-lymphangiography improves the visualization of the main lymphatic thoracic and abdominal vessels, particularly the abdominal and cervical part as well as the inferior segment of the thoracic duct.


Assuntos
Vasos Linfáticos , Linfografia , Meios de Contraste , Humanos , Vasos Linfáticos/diagnóstico por imagem , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Ducto Torácico/diagnóstico por imagem
17.
Waste Manag ; 102: 432-440, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31734554

RESUMO

Hydrothermal conversion (HTC) of sewage sludge (SS) and its relevant model compounds such as cellulose, glucose, lignin and soybean protein (substitute for protein) was experimentally conducted at moderate reaction temperature of 260 °C for 60 min. The structural properties, carbon-containing groups, and microstructure of the char were characterised by several techniques. The results revealed that more benzene rings were formed by small clusters and the CO bond on Aryl-alkyl ether decomposed on the surface particles during the HTC process. In addition, the catalyst Zeolite Socony Mobil-5 (ZSM-5, Si/Al: 300) showed an excellent performance on the high graphite degree of the char under moderate reaction temperature of 260 °C. In particular, cellulose has the most dramatic influence on the depolymerisation of C(C,H). As evidenced with SEM, the size of the char derived from SS with ZSM-5 catalyst is 10-15 µm, which is smaller than the char without catalyst. A mechanism for derivation of char from individual model compounds is proposed. The end products of lignin are composed of polyaromatic char, while the composition of the char derived from protein suggests that polymerisation may occur during hydrothermal reaction leading to formation of structures with N-containing compounds.


Assuntos
Carbono , Esgotos , Lignina , Temperatura
18.
Rofo ; 192(7): 669-677, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32018303

RESUMO

PURPOSE: To compare true positive and false negative results of myocardial edema mapping in two methods. Myocardial edema may be difficult to detect on cardiac MRI. MATERIALS AND METHODS: 76 patients (age 59 ±â€Š11 years, 15 female) with acute myocardial infarction (MI) and 10 healthy volunteers were prospectively included in this single-center study. 1.5 T cardiac MRI was performed in patients 2.5 days after revascularization (median) for edema mapping: Steady State Free Precession (SSFP) mapping sequence with T2-preparation pulses (T2prep); and dual-contrast Fast Spin-Echo (dcFSE) signal decay edema mapping. Late gadolinium enhancement (LGE) was used as the reference for expected edema in acute MI. RESULTS: 311 myocardial segments in patients were acutely infarcted with mean T2 73 ms for T2prep SSFP vs. 87 ms for dcFSE edema mapping. In healthy volunteers the mean T2 was 56 ms for T2prep SSFP vs. 50 ms for dcFSE edema mapping. Receiver operating characteristic (ROC) curve for T2prep SSFP show area under the curve (AUC) 0.962, p < 0.0001, Youden index J 0.8266, associated criterion > 60 ms, sensitivity 94 %, specificity 89 %. dcFSE ROC AUC 0.979, p < 0.0001, J 0.9219, associated criterion > 64 ms, sensitivity 93 %, specificity 99 %. CONCLUSION: Both edema mapping methods indicate high-grade edema with high sensitivity. Nevertheless, edema in acute infarction may be focally underestimated in both mapping methods. KEY POINTS: · Sensitivity for edema detection is high for both methods.. · Edema may be focally underestimated by T2prep SSFP edema mapping and dcFSE mapping.. CITATION FORMAT: · Krumm P, Martirosian P, Rath D et al. Performance of two Methods for Cardiac MRI Edema Mapping: Dual-Contrast Fast Spin-Echo and T2 Prepared Balanced Steady State Free Precession. Fortschr Röntgenstr 2020; 192: 669 - 677.


Assuntos
Edema Cardíaco/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Reações Falso-Negativas , Feminino , Gadolínio , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade
19.
Energy Fuels ; 33(10): 9843-9850, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-32952287

RESUMO

Food and market waste (FMW) is one of the most abundant unrecycled products which poses waste management issues and negative environmental impacts. Thermo-catalytic reforming (TCR) is a pyrolysis based technology which can convert a wide range of biomass wastes into energy vectors bio-oil, syngas, and char. This paper investigates the conversion potential of FMW into sustainable biofuels. The FMW was processed using a laboratory scale 2 kg/h TCR reactor. The process produced 7 wt % organic bio-oil, 53 wt % permanent gas, and 22 wt % char. The bio-oil higher heating value (HHV) was found to be 36.72 MJ/kg, comparable to biodiesel, and contained a low oxygen content (<5%) due to cracking of higher molecular weight organics. Naphthalene was detected to be the most abundant aromatic compound within the oil, with relative abundance of 12.95% measured by GC-MS. The total acid number of the oil (TAN) and viscosity were 11.7 mg KOH/g and 6.3 cSt, respectively. The gross calorific value of the produced biochar was 23.64 MJ/kg, while the permanent gas showed a higher heating value of approximately 17 MJ/Nm3. Methane (CH4) was found to be the largest fraction in the permanent gases reaching over 23%. This resulted either due to the partial methanation of biosyngas over the catalytically active FMW biochar or the hydrogenation of coke deposited on the biochar in the post reforming stage.

20.
Waste Manag ; 91: 42-53, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31203941

RESUMO

A life cycle thinking approach focusing on energy and greenhouse gas savings has been applied to study the potential for energy recovery and organic matter reclamation from Waste Activated Sludge produced in Waste Water Treatment Plants by means of a catalytic thermo-chemical process. A generic Basic Sludge Processing line has been modelled following common waste water and sludge treatment stages found in several European plants. This has served to identify and divide generic sludge treatment units in order to compare the performance of different industrial configurations where a specific thermo-chemical technology treatment unit and related cogeneration was substituted or added to reference units. The considered technology is an enhanced intermediate pyrolysis screw reactor combined with a reforming process known as Thermo-Catalytic Reforming allowing for conversion of sewage sludge into energy carriers and reclamation of organic substances in the form of charcoal (biochar). In order to study the greenhouse gas savings, a calculator tool complying with Directive 2009/28/EC has been adopted. Results show that substantial benefits in terms of energy production and greenhouse gas emissions reduction of a sludge-to-energy system are expected if the secondary sludge is directly treated with the Thermo-Catalytic Reforming process, without an intermediate anaerobic digestion step.


Assuntos
Gases de Efeito Estufa , Esgotos , Parafusos Ósseos , Pirólise , Eliminação de Resíduos Líquidos , Águas Residuárias
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