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1.
J Nucl Cardiol ; 30(3): 1091-1102, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36284033

RESUMO

BACKGROUND: In patients with multi-vessel disease presenting with ST elevation myocardial infarction (STEMI), the efficacy and safety of ischemia-guided, vs routine non-culprit vessel angioplasty has not been adequately studied. METHODS: We conducted an international, randomized, non-inferiority trial comparing ischemia-guided non-culprit vessel angioplasty to routine non-culprit vessel angioplasty, following primary PCI for STEMI. The primary outcome was the between-group difference in percent ischemic myocardium at follow-up stress MPI. All MPI images were processed and analyzed at a central core lab, blinded to treatment allocation. RESULTS: In all, 109 patients were enrolled from nine countries. In the ischemia-guided arm, 25/48 (47%) patients underwent non-culprit vessel PCI following stress MPI. In the routine non-culprit PCI arm, 43/56 (77%) patients underwent angioplasty (86% within 6 weeks of randomization). The median percentage of ischemic myocardium on follow-up imaging (mean 16.5 months) was low, and identical (2.9%) in both arms (difference 0.13%, 95%CI - 1.3%-1.6%, P < .0001; non-inferiority margin 5%). CONCLUSION: A strategy of ischemia-guided non-culprit PCI resulted in low ischemia burden, and was non-inferior to a strategy of routine non-culprit vessel PCI in reducing ischemia burden. Selective non-culprit PCI following STEMI offers the potential for cost-savings, and may be particularly relevant to low-resource settings. (CTRI/2018/08/015384).


Assuntos
Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Angioplastia , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Tomografia Computadorizada de Emissão de Fóton Único , Resultado do Tratamento
2.
Faraday Discuss ; 202: 403-413, 2017 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-28660970

RESUMO

In recent years, lignin valorization has gained upward momentum owing to advances in both plant bioengineering and catalytic processing of lignin. In this new horizon, catalysis is now applied to the 'pulping process' itself, creating efficient methods for lignocellulose fractionation or deconstruction (here referred to as Catalytic Upstream Biorefining or 'CUB'). These processes render, together with delignified pulps, lignin streams of low molecular weight (Mw) and low molecular diversity. Recently, we introduced a CUB process based on Early-stage Catalytic Conversion of Lignin (ECCL) through H-transfer reactions catalyzed by RANEY® Ni. This approach renders a lignin stream obtained as a viscous oil, comprising up to 60 wt% monophenolic compounds (Mw < 250 Da). The remaining oil fraction (40 wt%) is mainly composed of lignin oligomers, and as minor products, holocellulose-derived polyols and lignin-derived species of high Mw (0.25-2 kDa). Simultaneously, the process yields a holocellulose pulp with a low content of residual lignin (<5 wt%). Despite the efficiency of aqueous solutions of 2-propanol as a solvent for lignin fragments and an H-donor, there is scant information regarding the CUB process carried out in the presence of primary alcohols, which often inhibit the catalytic activity of RANEY® Ni, as revealed in model compound studies performed at low temperature. Considering the composition of the lignin oils obtained from CUB based on ECCL, the processes commonly render ortho-(di)methoxy-4-propylphenol derivatives with a varied degree of defunctionalization of the propyl side chain. In this contribution, we present the role of the alcohol solvent (methanol or 2-propanol) and Ni catalyst (Ni/C or RANEY® Ni) in control over selectivity of phenolic products. The current results indicate that solvent effects on the catalytic processes could hold the key for improving control over the degree of functionalization of the propyl side-chain in the lignin oil obtained from CUB, offering new avenues for lignin valorization at the extraction step.


Assuntos
Metanol/metabolismo , Fenóis/metabolismo , Catálise , Lignina/química , Lignina/metabolismo , Metanol/química , Níquel/química , Fenóis/química
3.
Angew Chem Int Ed Engl ; 56(9): 2334-2339, 2017 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-28128486

RESUMO

A simple and efficient hydrodeoxygenation strategy is described to selectively generate and separate high-value alkylphenols from pyrolysis bio-oil, produced directly from lignocellulosic biomass. The overall process is efficient and only requires low pressures of hydrogen gas (5 bar). Initially, an investigation using model compounds indicates that MoCx /C is a promising catalyst for targeted hydrodeoxygenation, enabling selective retention of the desired Ar-OH substituents. By applying this procedure to pyrolysis bio-oil, the primary products (phenol/4-alkylphenols and hydrocarbons) are easily separable from each other by short-path column chromatography, serving as potential valuable feedstocks for industry. The strategy requires no prior fractionation of the lignocellulosic biomass, no further synthetic steps, and no input of additional (e.g., petrochemical) platform molecules.

4.
Angew Chem Int Ed Engl ; 55(29): 8164-215, 2016 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-27311348

RESUMO

Lignin is an abundant biopolymer with a high carbon content and high aromaticity. Despite its potential as a raw material for the fuel and chemical industries, lignin remains the most poorly utilised of the lignocellulosic biopolymers. Effective valorisation of lignin requires careful fine-tuning of multiple "upstream" (i.e., lignin bioengineering, lignin isolation and "early-stage catalytic conversion of lignin") and "downstream" (i.e., lignin depolymerisation and upgrading) process stages, demanding input and understanding from a broad array of scientific disciplines. This review provides a "beginning-to-end" analysis of the recent advances reported in lignin valorisation. Particular emphasis is placed on the improved understanding of lignin's biosynthesis and structure, differences in structure and chemical bonding between native and technical lignins, emerging catalytic valorisation strategies, and the relationships between lignin structure and catalyst performance.


Assuntos
Bioengenharia , Biocombustíveis , Lignina/biossíntese , Biocatálise , Lignina/química , Lignina/isolamento & purificação
5.
Angew Chem Int Ed Engl ; 55(31): 8850-5, 2016 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-27294563

RESUMO

Hydrodeoxygenation (HDO) is an attractive route for the upgrading of bio-oils produced from lignocellulose. Current catalysts require harsh conditions to effect HDO, decreasing the process efficiency in terms of energy and carbon balance. Herein we report a novel and facile method for synthesizing bimetallic PtCo nanoparticle catalysts (ca. 1.5 nm) highly dispersed in the framework of nitrogen-doped ordered mesoporous carbon (NOMC) for this reaction. We demonstrate that NOMC with either 2D hexagonal (p6m) or 3D cubic (Im3‾ m) structure can be easily synthesized by simply adjusting the polymerization temperature. We also demonstrate that PtCo/NOMC (metal loading: Pt 9.90 wt %; Co 3.31 wt %) is a highly effective catalyst for HDO of phenolic compounds and "real-world" biomass-derived phenolic streams. In the presence of PtCo/NOMC, full deoxygenation of phenolic compounds and a biomass-derived phenolic stream is achieved under conditions of low severity.

6.
BMC Infect Dis ; 15: 244, 2015 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-26116560

RESUMO

BACKGROUND: The aim of this study was to characterize the spread of carbapenemase-producing Klebsiella pneumoniae (CPKP) in a tertiary level hospital using ongoing active surveillance with rectal swab cultures. Furthermore, this study analyzed the presence of CPKP in the clinical samples (CS) of a single patient as well as the evolution of Colistin-sensitive strains (CoS) to Colistin-resistant strains (CoR). METHODS: This study was performed from January 1, 2012 to December 31, 2014. In 2012, a survey was conducted in the Intensive Care Department. In autumn 2013, active monitoring was extended to the Surgery Department, and since mid-2014, the surveillance has included the Medical Department as well. Only the first isolated strain from each patient was included. Antimicrobial susceptibility testing was performed on CPKP isolates: Klebsiella pneumoniae carbapenemase, oxacillinase-48, Verona integron-encoded metallo-ß-lactamase and New Delhi metallo-ß-lactamase were detected using a validated in-house PCR method, and multilocus sequence typing (MLST) was used to investigate the clonal transmission of strains. RESULTS: A total of 15,104 patients were included in the study, and 496 consecutive non-replicated strains of CPKP were collected: 149 strains were collected in 2012 (39 [26.2 %] from surveillance rectal swabs [SRS]), 133 strains were collected in 2013 (70 [52.6 %] from SRS) and 214 strains were collected in 2014 (164 [76.6 %] from SRS). We observed a significant increase in the percentage of positive SRS cases in 2014 relative to 2013 and 2012 (p = 0.0001 and p = 0.0172, respectively) and in the proportion of CPKP first isolated by SRS relative to those identified by CS (p < 0.0001). Among all available samples, the number of CoR isolated from SRS was higher in 2013 and 2014 compared with 2012 (p = 0.0019 and p = 0.008, respectively). ST-258 and ST-512 were more prevalent in the tested specimens, and a new single locus variant (SLV) of ST-512 (ST-745) was isolated. CONCLUSIONS: The results of this 3-year study of 15,104 patients highlight the clinical relevance of antimicrobial resistance as well as the drug-selection pressure of colistin therapy. The active surveillance in the three different departments increased the level of CPKP cases isolated by SRS.


Assuntos
Antibacterianos , Proteínas de Bactérias/metabolismo , Colistina , Farmacorresistência Bacteriana , Infecções por Klebsiella/epidemiologia , Klebsiella pneumoniae/metabolismo , beta-Lactamases/metabolismo , Evolução Biológica , Hospitais de Ensino , Humanos , Unidades de Terapia Intensiva , Itália/epidemiologia , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/fisiologia , Testes de Sensibilidade Microbiana , Epidemiologia Molecular , Tipagem de Sequências Multilocus , Reação em Cadeia da Polimerase , Prevalência , beta-Lactamases/genética
7.
Angew Chem Int Ed Engl ; 53(33): 8634-9, 2014 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-24920053

RESUMO

Through catalytic hydrogen transfer reactions, a new biorefining method results in the isolation of depolymerized lignin--a non-pyrolytic lignin bio-oil--in addition to pulps that are amenable to enzymatic hydrolysis. Compared with organosolv lignin, the lignin bio-oil is highly susceptible to further hydrodeoxygenation under low-severity conditions and therefore establishes a unique platform for lignin valorization by heterogeneous catalysis. Overall, the potential of a catalytic biorefining method designed from the perspective of lignin utilization is reported.


Assuntos
Biomassa , Lignina/química , Lignina/metabolismo , 2-Propanol/química , Catálise , Endo-1,4-beta-Xilanases/metabolismo , Hidrogênio/química , Hidrólise , Níquel/química , Plantas/metabolismo
8.
Clin Infect Dis ; 57(6): 803-11, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23784926

RESUMO

BACKGROUND: A single-nucleotide polymorphism (SNP; rs12979860) near the IL28B gene has been associated with spontaneous and treatment-induced hepatitis C virus clearance. We investigated predictors of spontaneous disease resolution in a cohort of patients with acute hepatitis C (AHC), analyzing epidemiological, clinical and virological parameters together with IL28B.rs12979860 genotypes and cell-mediated immunity (CMI). METHODS: Fifty-six symptomatic AHC patients were enrolled and followed prospectively. CMI was measured in 31 patients at multiple time points by interferon-γ enzyme-linked immunospot assay and was correlated to the IL28B.rs12979860 SNP. RESULTS: Eighteen patients had a self-limiting AHC that was associated with female sex (P = .028), older age (P = .018), alanine aminotransferase level >1000 U/L (P = .027), total bilirubin level >7 mg/dL (P = .036), and IL28B.rs12979860 genotype CC (P = .030). In multivariate analysis, only CC genotype was independently associated with self-limiting AHC (odds ratio, 5.3; 95% confidence interval, 1.1-26.5). Patients with the CC genotype with self-limiting AHC had a stronger (P = .02) and broader (P = .013) CMI than patients with the CT genotype with chronically evolving AHC. In patients with chronically evolving disease, CC genotype was associated with a broader CMI compared to CT genotype (P = .028). A negative CMI was more frequently associated with CT genotype among persistently infected patients (P = .043) and with persistent infection among CT patients (P = .033). CONCLUSIONS: . Self-limiting AHC was independently associated with CC genotype. The correlation between IL28B.rs12979860 genotypes and CMI is suggestive of a possible important role of CMI in favoring hepatitis C virus clearance in CC patients.


Assuntos
Hepatite C/genética , Hepatite C/imunologia , Interleucinas/genética , Doença Aguda , Adulto , Idoso , Feminino , Hepatite C/epidemiologia , Humanos , Interferons , Interleucinas/imunologia , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Polimorfismo de Nucleotídeo Único , Prognóstico , Estudos Prospectivos
9.
Chemistry ; 19(48): 16282-94, 2013 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-24136817

RESUMO

The molecular understanding of the chemistry of 1,4-ß-glucans is essential for designing new approaches to the conversion of cellulose into platform chemicals and biofuels. In this endeavor, much attention has been paid to the role of hydrogen bonding occurring in the cellulose structure. So far, however, there has been little discussion about the implications of the electronic nature of the 1,4-ß-glycosidic bond and its chemical environment for the activation of 1,4-ß-glucans toward acid-catalyzed hydrolysis. This report sheds light on these central issues and addresses their influence on the acid hydrolysis of cellobiose and, by analogy, cellulose. The electronic structure of cellobiose was explored by DFT at the BB1 K/6-31++G(d,p) level. Natural bond orbital (NBO) analysis was performed to grasp the key bonding concepts. Conformations, protonation sites, and hydrolysis mechanisms were examined. The results for cellobiose indicate that cellulose is protected against hydrolysis not only by its supramolecular structure, as currently accepted, but also by its electronic structure, in which the anomeric effect plays a key role.


Assuntos
Celobiose/química , Celulose/química , Ligação de Hidrogênio , Hidrólise , Estrutura Molecular , Termodinâmica
10.
Angew Chem Int Ed Engl ; 52(44): 11499-503, 2013 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-24030931

RESUMO

Finding a workaround: The conversion of lignin into low-boiling-point arenes instead of high-boiling-point phenols could greatly facilitate conventional refinery processes. A new procedure for the depolymerization of lignin and simultaneous conversion phenols into arenes is described. The method can also be rendered as a fundamental finding for the upgrade of bio-oils to arenes under mild conditions.


Assuntos
Lignina/química , Fenóis/química , Catálise , Hidroxilação , Óleos
11.
ChemSusChem ; 16(3): e202201875, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36469562

RESUMO

Reductive Catalytic Fractionation (RCF) of lignocellulosic materials produces lignin oil rich in monomer products and high-quality cellulosic pulps. RCF lignin oil also contains lignin oligomers/polymers and hemicellulose-derived carbohydrates. The variety of components makes lignin oil a complex matrix for analytical methods. As a result, the signals are often convoluted and overlapped, making detecting and quantifying key intermediates challenging. Therefore, to investigate the mechanisms underlining lignin stabilization and elucidate the structural features of carbohydrates occurring in the RCF lignin oil, fractionation methods reducing the RCF lignin oil complexity are required. This report examines the solvent fractionation of RCF lignin oil as a facile method for producing lignin oil fractions for advanced characterization. Solvent fractionation uses small volumes of environmentally benign solvents (methanol, acetone, and ethyl acetate) to produce multigram lignin fractions comprising products in different molecular weight ranges. This feature allows the determination of structural heterogeneity across the entire molecular weight distribution of the RCF lignin oil by high-resolution HSQC NMR spectroscopy. This study provides detailed insight into the role of the hydrogenation catalyst (Raney Ni) in stabilizing lignin fragments and defining the structural features of hemicellulose-derived carbohydrates in lignin oil obtained by the H-transfer RCF process.

12.
Clin Infect Dis ; 55(4): 497-503, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22539662

RESUMO

BACKGROUND: Primary cytomegalovirus (CMV) infection during pregnancy is the leading infectious cause of congenital neurological disabilities. Early CMV infection carries a higher risk of adverse neonatal outcome (sensorineural hearing loss or neurological deficits). Intravenous hyperimmunoglobulin (HIG) therapy seems to be promising, but its efficacy needs further investigation. METHODS: Since 2002, we have enrolled consecutively all pregnant women with early (ie, before gestational week 17) CMV infection. Beginning in 2007, all women were offered treatment with HIG (200 UI per kilogram of maternal weight, in a single intravenous administration). Outcome of infants was evaluated at the age of 1 year. RESULTS: Of the 592 women with early primary CMV infection, amniocentesis for CMV DNA detection was performed for 446. Of the 92 CMV-positive fetuses, pregnancy was terminated for 24, HIG was administered to mothers of 31, and no treatment was received by mothers of 37. Fetuses of treated mothers did not differ from fetuses of nontreated mothers according to mother's age, gestational week of infection, CMV load, or detection of abnormal ultrasonography findings. At the 1-year evaluation, 4 of 31 infants with treated mothers (13%; 95% confidence interval [CI], 1%-25%) and 16 of 37 infants with nontreated mothers (43%; 95% CI, 27%-59%) presented with poor outcomes (P < .01, by the 2-tailed Fisher exact test). CONCLUSIONS: HIG treatment improved the outcome of fetuses from women who had primary CMV infection before gestational week 17.


Assuntos
Infecções por Citomegalovirus/terapia , Imunização Passiva/métodos , Complicações Infecciosas na Gravidez/terapia , Complicações Infecciosas na Gravidez/virologia , Adulto , Amniocentese , Líquido Amniótico/virologia , Anticorpos Antivirais/uso terapêutico , Distribuição de Qui-Quadrado , Infecções por Citomegalovirus/virologia , Feminino , Humanos , Recém-Nascido , Misoprostol/uso terapêutico , Gravidez , Estudos Prospectivos
16.
Front Chem ; 9: 816553, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35047484

RESUMO

Mechanochemistry utilizes mechanical forces to activate chemical bonds. It offers environmentally benign routes for both (bio) organic and inorganic syntheses. However, direct comparison of mechanochemistry results is often very challenging. In mechanochemical synthetic protocols, ball mill setup (mechanical design and grinding vessel geometry) in addition to experimental parameters (milling frequency, duration, ball count and size) vary broadly. This fact poses a severe issue to further progress in this exciting research area because ball mill setup and experimental parameters govern how much kinetic energy is transferred to a chemical reaction. In this work, we address the challenge of comparing mechanochemical reaction results by taking the energy dose provided by ball mills as a unified metric into account. In this quest, we applied kinematic modeling to two ball mills functioning under distinct working principles to express the energy dose as a mathematical function of the experimental parameters. By examining the effect of energy dose on the extent of the mechanocatalytic depolymerization (MCD) of lignocellulosic biomass (beechwood), we found linear correlations between yield of water-soluble products (WSP) and energy dose for both ball mills. Interestingly, when a substrate layer is formed on the grinding jar wall and/or grinding medium, a weak non-linear correlation between water-soluble products yield and energy dose is identified. We demonstrate that the chemical reaction's best utilization of kinetic energy is achieved in the linear regime, which presents improved WSP yields for given energy doses. In the broader context, the current analysis outlines the usefulness of the energy dose as a unified metric in mechanochemistry to further the understanding of reaction results obtained from different ball mills operating under varied experimental conditions.

17.
J Nucl Med Technol ; 49(1): 84-85, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33020233

RESUMO

Respiratory motion artifacts may affect interpretation of whole-body 18F-FDG PET/CT scans, especially when lesions are localized between the liver and the lung. We report a case of a patient with breast cancer who underwent PET/CT after therapy and in whom focal 18F-FDG uptake of equivocal interpretation was observed between the liver and the pleura. A subsequent imaging acquisition of the right lateral decubitus showed that the lesion had a pleural location, thus improving the diagnostic accuracy of the PET/CT finding.


Assuntos
Artefatos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Fluordesoxiglucose F18 , Humanos , Pulmão , Movimento (Física) , Tomografia por Emissão de Pósitrons
18.
Artigo em Inglês | MEDLINE | ID: mdl-33922904

RESUMO

There are few long-term nutritional studies in subjects undergoing bariatric surgery that have assessed weight regain and nutritional deficiencies. In this study, we report data 8 years after surgery on weight loss, use of dietary supplements and deficit of micronutrients in a cohort of patients from five centres in central and northern Italy. The study group consisted of 52 subjects (age: 38.1 ± 10.6 y, 42 females): 16 patients had Roux-en-Y gastric bypass (RYGB), 25 patients had sleeve gastrectomy (SG) and 11 subjects had adjustable gastric banding (AGB). All three bariatric procedures led to sustained weight loss: the average percentage excess weight loss, defined as weight loss divided by excess weight based on ideal body weight, was 60.6% ± 32.3. Despite good adherence to prescribed supplements, 80.7% of subjects (72.7%, AGB; 76.7%, SG; 93.8 %, RYGB) reported at least one nutritional deficiency: iron (F 64.3% vs. M 30%), vitamin B12 (F 16.6% vs. M 10%), calcium (F 33.3% vs. M 0%) and vitamin D (F 38.1% vs. M 60%). Long-term nutritional deficiencies were greater than the general population among men for iron and among women for vitamin B12.


Assuntos
Cirurgia Bariátrica , Obesidade Mórbida , Deficiência de Vitamina B 12 , Adulto , Cirurgia Bariátrica/efeitos adversos , Suplementos Nutricionais , Feminino , Humanos , Ferro , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Obesidade Mórbida/cirurgia , Estudos Retrospectivos , Deficiência de Vitamina B 12/epidemiologia , Deficiência de Vitamina B 12/etiologia
19.
Br J Radiol ; 94(1123): 20200672, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34106736

RESUMO

OBJECTIVES: High-dose CT (HDCT) is considered the gold-standard imaging for the measurements of skeletal muscle area (SMA), visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT) and intramuscular adipose tissue (IMAT) areas in the abdomen. These parameters may reflect sarcopenia, which can have a prognostic impact in several oncological diseases. The aim of this study was to compare the agreement of measurements of SMA, VAT, SAT and IMAT areas between HDCT and low-dose CT (LDCT) of 18-fludeoxyglucose positron emission tomography (18F-FDG PET)/CT in elderly patients affected by Hodgkin lymphoma (HL). METHODS: We retrospectively included 90 patients affected by HL who underwent baseline 18F-FDG-PET/CT and HDCT within a mean interval of 7 days. HDCT and LDCT images were analysed by two blinded observers using segmentation software (Slice-O-Matic, Tomovision) to quantify the areas. HDCT and LDCT measurements were compared using Bland-Altman plots and Passing-Bablock regression analyses. Pearson correlation coefficient (r) was used to correlate measurements from the two imaging modalities. RESULTS: Comparison of HDCT and LDCT data demonstrated a strong correlation for measurement of VAT(r = 0.942, p < 0.0001), SAT (r = 0.894, p < 0.0001) and SMA (r = 0.934, p < 0.0001). Instead considering IMAT, correlation was good but less significant (r = 0.742). The mean difference between the two methods was found to be very small, with a difference of 1% for SAT,+6.1% for VAT,+2.5% for SMA and -1.9% for IMAT. CONCLUSION: LDCT of PET/CT is a safe, accurate and precise method for the measurements of skeletal muscle area, visceral and subcutaneous adipose tissue. Their measurements are reproducible and correlate closely with HDCT. ADVANCES IN KNOWLEDGE: LLDCT of PET/CT is a safe and accurate method for the measurements of SMA, VAT and SAT; their measurements are closely correlated with HDCT. LDCT can be considered an accurate alternative tool for measuring abdominal fat and muscles in the clinical practice.


Assuntos
Tecido Adiposo/diagnóstico por imagem , Doença de Hodgkin/diagnóstico por imagem , Músculo Esquelético/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Sarcopenia/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Idoso , Idoso de 80 Anos ou mais , Feminino , Fluordesoxiglucose F18 , Doença de Hodgkin/patologia , Humanos , Masculino , Estadiamento de Neoplasias , Interpretação de Imagem Radiográfica Assistida por Computador , Compostos Radiofarmacêuticos , Estudos Retrospectivos , Software
20.
Energy Environ Sci ; 14(8): 4147-4168, 2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-36324336

RESUMO

Reductive catalytic fractionation (RCF) is a promising approach to fractionate lignocellulose and convert lignin to a narrow product slate. To guide research towards commercialization, cost and sustainability must be considered. Here we report a techno-economic analysis (TEA), life cycle assessment (LCA), and air emission analysis of the RCF process, wherein biomass carbohydrates are converted to ethanol and the RCF oil is the lignin-derived product. The base-case process, using a feedstock supply of 2000 dry metric tons per day, methanol as a solvent, and H2 gas as a hydrogen source, predicts a minimum selling price (MSP) of crude RCF oil of $1.13 per kg when ethanol is sold at $2.50 per gallon of gasoline-equivalent ($0.66 per liter of gasoline-equivalent). We estimate that the RCF process accounts for 57% of biorefinery installed capital costs, 77% of positive life cycle global warming potential (GWP) (excluding carbon uptake), and 43% of positive cumulative energy demand (CED). Of $563.7 MM total installed capital costs, the RCF area accounts for $323.5 MM, driven by high-pressure reactors. Solvent recycle and water removal via distillation incur a process heat demand equivalent to 73% of the biomass energy content, and accounts for 35% of total operating costs. In contrast, H2 cost and catalyst recycle are relatively minor contributors to operating costs and environmental impacts. In the carbohydrate-rich pulps, polysaccharide retention is predicted not to substantially affect the RCF oil MSP. Analysis of cases using different solvents and hemicellulose as an in situ hydrogen donor reveals that reducing reactor pressure and the use of low vapor pressure solvents could reduce both capital costs and environmental impacts. Processes that reduce the energy demand for solvent separation also improve GWP, CED, and air emissions. Additionally, despite requiring natural gas imports, converting lignin as a biorefinery co-product could significantly reduce non-greenhouse gas air emissions compared to burning lignin. Overall, this study suggests that research should prioritize ways to lower RCF operating pressure to reduce capital expenses associated with high-pressure reactors, minimize solvent loading to reduce reactor size and energy required for solvent recovery, implement condensed-phase separations for solvent recovery, and utilize the entirety of RCF oil to maximize value-added product revenues.

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