RESUMO
For the first time, ultrasonic emulsification was studied for cinnamon essential oil (CEO) Pickering emulsion, stabilized by cellulose nanocrystal (CNC) from rice straw. Sonication proved to be an effective method for emulsifying CEO, creating small emulsion droplets around 700 nm in size, with an even dispersion characterized through a low polydispersity index. The biomass-derived CNC exhibits high encapsulation efficiency (> 95 %) with varying CEO concentration (5-25 vol%), creating droplets with negative surface charge with limited aggregation of emulsions. Optimization through the Box Behnken design using response surface methodology provides a model for the interaction and effects of variables towards the formulation. Optimal condition was concluded to be at 11.47 vol% CEO, 0.84 wt/vol% CNC and at 6 sonication cycles. The optimized Pickering emulsions retain the antimicrobial properties of CEO, with a large inhibition zone and low MIC value of around 0.048 vol% CEO. DPPH inhibition assay indicates that the emulsification process enhances the antioxidation properties of cinnamon essential oil, expressed through a lower IC50 of 0.90 vol% CEO, in comparison to pure essential oil at 1.33 vol% CEO. Overall, this research proposes a novel approach towards using nanocellulose as carriers for essential oil with potential in a large variety of applications.
Assuntos
Celulose , Cinnamomum zeylanicum , Emulsões , Nanopartículas , Óleos Voláteis , Oryza , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Nanopartículas/química , Celulose/química , Emulsões/química , Cinnamomum zeylanicum/química , Oryza/química , Antioxidantes/química , Antioxidantes/farmacologia , Tamanho da PartículaRESUMO
Finding the ground state of a quantum many-body system is a fundamental problem in quantum physics. In this work, we give a classical machine learning (ML) algorithm for predicting ground state properties with an inductive bias encoding geometric locality. The proposed ML model can efficiently predict ground state properties of an n-qubit gapped local Hamiltonian after learning from only [Formula: see text] data about other Hamiltonians in the same quantum phase of matter. This improves substantially upon previous results that require [Formula: see text] data for a large constant c. Furthermore, the training and prediction time of the proposed ML model scale as [Formula: see text] in the number of qubits n. Numerical experiments on physical systems with up to 45 qubits confirm the favorable scaling in predicting ground state properties using a small training dataset.
RESUMO
Depolymerization of lignin is an important step to obtain a lignin monomer for the synthesis of functional chemicals. In the context of more lignin produced from biomass and pulp industry, converting real lignin with low purity is still required more studies. In this study, the influence of solvent composition and reaction parameters such as binary solvents ratio, time, and temperature, the solvent-to-lignin ratio on the depolymerization of rice straw lignin was investigated carefully. Essential lignin-degraded products including liquid product (LP), char (solid), and gas were obtained, and their yields were directly influenced by reaction conditions. Results show that the maximum lignin conversion rate of 92% and LP yield of 66% was under the condition of 275°C, 30 min, 75 : 1 (mL solvent/1 g lignin), and ethanol 50%. Gas chromatography-mass spectroscopy (GC-MS) analysis was used for the analysis of the depolymerization products and identified 11 compounds which are mainly phenolic compounds such as 2-ethylphenol, 3-ethylphenol, phenol, methyl 2,4,6-trimethylbenzoate. The structure changes of LP and char in various conditions were analyzed using Fourier-transform infrared (FTIR).
Assuntos
Lignina , Oryza , Biomassa , Etanol/química , Lignina/química , Solventes/químicaRESUMO
Improvement of biomass utilization productivity following cascading strategy is a priority for the biorefinery-based circular bioeconomy. In recent years, the field of energy research has seen an increasing interest in bio-products from paddy-based biorefinery, but the utilization of the entire value of paddy biomass to guide the commercial viability of its products has not been got feasible outcomes. Here we propose a potential pathway for a conceptual paddy biorefinery framework by addressing wastes for producing more products. The feasibility of the integrated biorefinery was demonstrated by the conversion of wastes into value-added products such as nano-silica and lignin. In particular, this is the first time that silica recovered from bioethanol system was continued to be reused to produce ZSM-5 and Ni/ZSM-5 as catalysts of rice straw lignin depolymerization achieving high conversion of lignin up to 95% and fair yield of phenolic products up to 41%. Material flow of an integrated biorefinery model was reported to give a future outlook for making most of the processing routes of rice residues. We also established a life cycle that follows the circular bioeconomy concept and discussed the relationship between each of potential bioproducts and their market opportunities.
Assuntos
Biocombustíveis , Lignina , Animais , Biomassa , Catálise , Estágios do Ciclo de VidaRESUMO
Difficulties in the production of lignin from rice straw because of high silica content in the recovered lignin reduce its recovery yield and applications as bio-fuel and aromatic chemicals. Therefore, the objective of this study is to develop a novel method to reduce the silica content in lignin from rice straw more effectively and selectively. The method is established by monitoring the precipitation behavior as well as the chemical structure of precipitate by single-stage acidification at different pH values of black liquor collected from the alkaline treatment of rice straw. The result illustrates the significant influence of pH on the physical and chemical properties of the precipitate and the supernatant. The simple two-step acidification of the black liquor at pilot-scale by sulfuric acid 20w/v% is applied to recover lignin at pH 9 and pH 3 and gives a percentage of silica removal as high as 94.38%. Following the developed process, the high-quality lignin could be produced from abundant rice straw at the industrial-scale.
RESUMO
Interruption of the aortic arch is practically always associated with intracardiac malformations of variable complexity, at the least, a ventricular septal defect. Surgery is usually performed in two stages: aortic repair and pulmonary artery banding after intravenous prostaglandin administration. The second stage comprises debanding and repair of the intracardiac lesions under cardiopulmonary bypass. However, in some cases, interruption of the aortic arch is associated with intracardiac lesions which necessitate correction under cardiopulmonary bypass from the onset, this was the situation in two of the three cases described by the authors: aorto-pulmonary window, a lesion which can only be corrected under circulatory arrest and deep hypothermia. One of these two children, operated in the neonatal period, did not survive: the other, operated at 6 weeks, had an excellent result. In the third case, the association of tricuspid atresia and a restrictive ventricular septal defect necessitated enlargement of the septal defect and therefore, open heart surgery under circulatory arrest; the results were favourable.
Assuntos
Aorta Torácica/anormalidades , Cardiopatias Congênitas/cirurgia , Aorta Torácica/cirurgia , Doenças da Aorta/cirurgia , Circulação Extracorpórea , Feminino , Fístula/cirurgia , Comunicação Interventricular/cirurgia , Humanos , Lactente , Recém-Nascido , Masculino , Métodos , Artéria Pulmonar/cirurgiaRESUMO
An experimental model of pulmonary stenosis was created in ewes, fetus and repaired before birth by making use of the materno-foetal circulation. Eighteen ewes fetus underwent pulmonary artery banding at an average of 87 +/- 8 days' gestation (normal 135-145 days). All were reoperated before term at 132 +/- 6 days' gestation. They were divided into two groups : group I (7 fetus) was used to evaluate the experimental model of pulmonary stenosis by measuring right ventricular pressures (80 +/- 16 mmHg compared to 58 +/- 10 mmHg in control models), and the increase in right ventricular mass (2.8 +/- 0.5 X 10(-3) g vs 1.9 +/- 0.2 X 10(-3) g), left ventricular mass (2.2 +/- 0.3 X 10(-3) g vs 1.8 +/- 0.4 X 10(-3) g) and septal mass (1.8 +/- 0.3 X 10(-3) g vs 1.3 +/- 0.2 X 10(-3) g). In group II (11 fetus) the pulmonary stenosis was repaired by total clamping and patch repair. After repair and during the days just before birth, the ventricular masses decreased (RV = 2 +/- 0.3 X 10(-3) g; LV = 1.8 +/- 0.4 X 10(-3) g; septum = 1.8 +/- 0.3 X 10(-3) g) approaching values of normal control fetus. This experimental model shows that it is possible to correct cardiac lesions in utero by making use of the materno-fetal circulation and that antenatal repair of an arterial obstruction can rapidly reverse the reactional ventricular hypertrophy.
Assuntos
Procedimentos Cirúrgicos Cardíacos , Coração/embriologia , Estenose da Valva Pulmonar/cirurgia , Animais , Feminino , Troca Materno-Fetal , Gravidez , OvinosRESUMO
From May 1977 to August 1982 50 patients who were 1.5 to 44 months old underwent anatomic correction of transposition of the great arteries (TGA) and closure of ventricular septal defect (VSD) at our institution. Thirty-nine patients underwent preliminary pulmonary arterial banding. Hospital mortality was 32%: four patients died as a result of technical problems, seven as a result of associated lesions, three of pulmonary hypertension, and two of left ventricular failure. Three other patients died after the first postoperative month (one of mediastinitis, one at reoperation for a residual VSD, and one of pulmonary hypertension). All 31 survivors are in excellent clinical condition and are in sinus rhythm after a mean follow-up period of 31 +/- 14 months. Twenty-five patients were reinvestigated by echocardiography (M mode and two-dimensional) and/or catheterization. Parameters of left ventricular contractility were within normal limits, but systolic aortic diameter was larger than normal (p less than .01). Seven patients had stenosis of the right ventricular outflow tract and five of these required reoperation. The two persistent problems with the anatomic correction of TGA associated with VSD are a relatively high operative mortality and secondary right outflow tract stenosis. However, use of this procedure results in better left ventricular function and fewer arrhythmias than does use of atrial repair techniques and also results in the use of the anatomically left ventricle as the systemic ventricle.
Assuntos
Comunicação Interventricular/cirurgia , Transposição dos Grandes Vasos/cirurgia , Cineangiografia , Constrição Patológica/etiologia , Vasos Coronários/cirurgia , Ecocardiografia/métodos , Seguimentos , Comunicação Interventricular/complicações , Comunicação Interventricular/fisiopatologia , Humanos , Lactente , Complicações Pós-Operatórias/mortalidade , Artéria Pulmonar/cirurgia , Reoperação , Transposição dos Grandes Vasos/complicações , Transposição dos Grandes Vasos/fisiopatologiaRESUMO
A new technique of correction of the truncus arteriosus avoiding the use of a prosthetic conduit is presented. The procedure described comprises anterior translation of the pulmonary bifurcation, reconstruction of the pulmonary outflow tract with a rim transected from the truncus, and direct implantation of the pulmonary artery.
Assuntos
Artéria Pulmonar/cirurgia , Persistência do Tronco Arterial/cirurgia , Humanos , Lactente , Recém-Nascido , MétodosRESUMO
Small diameter aortic valve bioprostheses are associated with resting ventriculo-aortic pressure gradients of 10 to 35 mmHg. In order to avoid this factor favouring degradation of left ventricular function and early deterioration of the bioprosthesis, we enlarged the aortic ring when the diameter was less than 23 mm in patients considered unsuitable for long-term anticoagulation. The surgical technique involved incising the annulus from the postero-lateral commissure to the anterior mitral leaflet and implanting a Dacron patch lined with pericardium. Nine patients aged from 10 to 70 years (average 22 years) underwent aortic valve replacement with a Carpentier-Edwards bioprosthesis associated with enlargement of the aortic ring, between June 1979 and December 1981. The mean follow-up period is now 18 months (range 9 to 39 months). One patient has been lost to follow-up. Before surgery, 6 patients were in Stage III and 3 patients in Stage IV of the NYHA classification. There were 4 patients with pure aortic regurgitation with valve prolapse, 1 patient with aortic regurgitation due to endocarditis, and 4 patients with mixed aortic valve disease. The underlying disease was rheumatic in 6 cases, congenital in 2 cases and infective endocarditis in 1 case. The mean diameter of the aortic ring before enlargement was 19 mm. After the procedure, it increased to 23,8 mm, so enabling the implantation of no 23 and no 25 bioprostheses. Three patients had associated mitral regurgitation, 3 patients had mixed mitral valve disease, 1 patient had a membranous VSD with infundibular stenosis, and 1 patient had subvalvular aortic stenosis.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Bioprótese , Próteses Valvulares Cardíacas , Adolescente , Adulto , Idoso , Valva Aórtica/cirurgia , Insuficiência da Valva Aórtica/congênito , Insuficiência da Valva Aórtica/cirurgia , Criança , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Cardiopatia Reumática/cirurgiaRESUMO
Between January, 1975, and January, 1982, 130 patients underwent mitral valvuloplasty for pure or predominant mitral insufficiency. Mean age at operation was 30 +/- 17 years. Twenty-five patients were under 15 years of age. Mitral insufficiency was mainly (112/130) due to rheumatic disease. Fifty-nine patients (45.4%) had another diseased valve which necessitated a surgical correction (tricuspid in 36 and aortic in 23). Surgical technique for mitral valvuloplasty varied according to the lesions. Three patients died in the first month after operation (2.3%). Five patients are lost to follow-up. The mean follow-up period for the 122 remaining patients is 38 +/- 27 months. Seven patients required reoperation and three of them died. An additional patient died without reoperation. Therefore, the late mortality was 3.1% (4/122). Almost all (116/118) of the remaining patients are in Class I (105) or II (11) of the New York Heart Association. Mean cardiothoracic ratio decreased from 60.6% +/- 7.7% preoperatively to 53.7% +/- 6.2% postoperatively (p less than 0.001). Thromboembolic episodes were noted in four patients, all of them in atrial fibrillation. Actuarial curves including hospital mortality showed a 92.0% survival rate at 7 years for the overall series (1.0% +/- 0.5%/patient-year), 93.7% +/- 4.9% at 7 years for isolated mitral reconstruction and 89.9% +/- 5.6% for mitral-tricuspid valvuloplasty at 5 years. The embolism-free rate at 7 years was 91.2%, with a rate of thromboembolic episodes of 1.0 +/- 0.5%/patient-year. Eighty-eight percent were free of reoperation at 7 years, with a rate of reoperation of 1.7 +/- 0.7%/patient-year. This system of mitral repair can provide stable functional results, low surgical and late mortality, and an acceptable rate of reoperation.
Assuntos
Insuficiência da Valva Mitral/cirurgia , Valva Mitral/cirurgia , Adolescente , Adulto , Idoso , Criança , Feminino , Seguimentos , Humanos , Masculino , Métodos , Pessoa de Meia-Idade , Complicações Pós-Operatórias/mortalidade , Recidiva , Reoperação , Cardiopatia Reumática/etiologia , Tromboembolia/etiologiaRESUMO
In coronary bypass surgery myocardial protection by injection of a cardioplegic fluid is made uneven by the presence of stenotic segments. In order to make it even, the authors suggest that the fluid should be injected first into the aortic origin, then into the coronary sinus. This method should provide greater safety when multiples bypasses are performed and in cases of impaired left ventricular function.