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1.
Waste Manag ; 176: 159-168, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38281347

RESUMEN

Pyrolysis is a promising method for recovering resources and energy products from municipal solid waste (MSW). Predicting MSW pyrolysis products is crucial for establishing an efficient pyrolysis system for resource recovery. In this study, a database was established based on MySQL to record relevant information on MSW pyrolysis, which includes the MSW ultimate analysis results, proximate analysis results, parameters of pyrolysis operation and yields of pyrolysis products, etc. Based on the database and with help of a deep artificial neural network (ANN) which contains 10 hidden layers, a prediction model was successfully established to predict the yield of char, liquid and gas products from MSW pyrolysis. The results showed that the coefficients of determination for predicting the yields of char, liquid and gas from the MSW pyrolysis are 0.841, 0.84, and 0.85, respectively; these values demonstrate an accuracy comparable to that achieved for product prediction from single biomass, indicating a successful model performance. The results also show that ash content and temperature are the most important input factors influencing the outputs, namely, yields of char, liquid and gas. The results of this study can help to achieve a more efficient design of the pyrolysis system and improve the recovery of the desired pyrolysis products.


Asunto(s)
Pirólisis , Residuos Sólidos , Residuos Sólidos/análisis , Temperatura , Redes Neurales de la Computación , Biomasa
2.
Adv Mater ; 36(7): e2308925, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37879753

RESUMEN

Neutral oxygen evolution reaction (OER) with unique reactive environments exhibits extremely slow reaction kinetics, posing significant challenges in the design of catalysts. Herein, a built-in electric field between the tungstate (Ni-FeWO4 ) with adjustable work function and Lewis acid WO3 is elaborately constructed to regulate asymmetric interfacial electron distribution, which promotes electron accumulation of Fe sites in the tungstate. This decelerates the rapid dissolution of Fe under the OER potentials, thereby retaining the active hydroxyl oxide with the optimized OER reaction pathway. Meanwhile, Lewis acid WO3 enhances hydroxyl adsorption near the electrode surface to improve mass transfer. As expected, the optimized Ni-FeWO4 @WO3 /NF self-supporting electrode achieves a low overpotential of 235 mV at 10 mA cm-2 in neutral media and maintains stable operation for 200 h. Furthermore, the membrane electrode assembly constructed by such self-supporting electrode exhibits robust stability for 250 h during neutral seawater electrolysis. This work deepens the understanding of the reconstruction of OER catalysts in neutral environments and paves the way for development of the energy conversion technologies.

3.
Environ Sci Pollut Res Int ; 30(58): 122611-122624, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37971593

RESUMEN

Phenol is one of the important ingredients of pyrolysis oil, contributing to the high biotoxicity of pyrolysis oil. To promote the degradation and conversion of phenol during anaerobic digestion, cheap hydro-chars with high phenol adsorption capacity were produced. The phenol adsorption capabilities of the plain hydro-char, plasma modified hydro-char at 25 °C (HC-NH3-P-25) and 500 °C (HC-NH3-P-500) were evaluated, and their adsorption kinetics and thermodynamics were explored. Experimental results indicate that the phenol adsorption capability of HC-NH3-P-500 was the highest. The phenol adsorption kinetics of all samples followed the pseudo-second-order equation and interparticle diffusion model, indicating that the adsorption rate of phenol was controlled by interparticle diffusion and chemistry adsorption simultaneously. By DFT calculations, π-π stacking and hydrogen bond are the main interactions for phenol adsorption. It was observed that an enriched graphite N content decreased the average vertical distance between hydro-chars and phenol in π-π stacking complex, from 3.5120 to 3.4532 Å, causing an increase in the negative adsorption energy between phenol and hydro-char from 13.9330 to 23.4181 kJ/mol. For hydrogen bond complex, the average vertical distance decreased from 3.4885 to 3.3386 Å due to the increase in graphite N content; causing the corresponding negative adsorption energy increased from 19.0233 to 19.9517 kJ/mol. Additionally, the presence of graphite N in the hydro-char created a positive diffusion region and enhanced the electron density between hydro-char and phenol. Analyses suggest that enriched graphite N contributed to the adsorption complex stability, resulting in an improved phenol adsorption capacity.


Asunto(s)
Grafito , Fenol , Fenol/química , Carbón Orgánico/química , Adsorción , Pirólisis , Fenoles , Cinética
4.
Heliyon ; 9(11): e21255, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37954285

RESUMEN

During the pyrolysis process of large particles, the conduction between particles cannot be ignored. In the present work, a numerical simulation model for the pyrolysis of biomass particles was established, which takes into account the conduction within the particles. Based on this model, the temperature distribution inside the particle during the pyrolysis process was determined and the effects of particle size, moisture content, and gas velocity on heat transfer characteristics were analyzed. The results showed that the temperatures at different positions of the particles along the inflow direction were quite different, and the maximum temperature difference inside the particles was about 146.7 K for a particle diameter of 10 mm and a velocity of 0.2 m/s. During the pyrolysis process of biomass particles, there were two peaks of Nusselt number. The increase of moisture content prolonged the pyrolysis time. The pyrolysis. time of particles with moisture content of 15 % was about 1.5 times longer than that of dry particles when the particle diameter was 10 mm. Increasing the particle size decreased the difference between the two peaks and increased the time interval between the two peaks. Increasing the gas velocity can improve the heat transfer, but the effect of too high gas velocity on improving the heat transfer is limited. The present study is of great importance for a detailed understanding of the pyrolysis process of biomass particles.

5.
Sci Bull (Beijing) ; 68(13): 1389-1398, 2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-37331904

RESUMEN

Electronic structure manipulation with regard to active site coordination is an effective strategy to improve the electrocatalytic oxygen evolution reaction (OER) activity. Herein, we present the structure-activity relationship between oxygen-atom-mediated electron rearrangement and active site coordination asymmetry. Ni2+ ions are introduced to FeWO4 on Ni foam (NF) via self-substitution to break the symmetry of the FeO6 octahedron and regulate d-electron structure of Fe sites. Structural regulation optimizes the adsorption energy of hydroxyl on the Fe sites and promotes the partial formation of hydroxyl oxide with high OER activity on the tungstate surface. Fe0.53Ni0.47WO4/NF with the asymmetric FeO6 octahedron of Fe sites can achieve an ultralow overpotential of 170 mV at 10 mA cm-2 and 240 mV at 1000 mA cm-2 with robust stability for 500 h at high current density under alkaline conditions. This research develops novel electrocatalysts with impressive OER performance and provides new insights into the design of highly active catalytic systems.

6.
Genes Dis ; 10(1): 151-164, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37013041

RESUMEN

Chronic inflammation caused by persistent infections and metabolic disorders is thought to contribute to the increased cancer risk and the accelerated cancer progression. Oppositely, acute inflammation induced by bacteria-based vaccines or that is occurring after cancer selectively inhibits cancer progression and metastasis. However, the interaction between inflammation and cancer may be more complex than the current explanations for the relationship between chronic and acute inflammation and cancer. In this review, we described the impact of inflammation on cancer on the basis of three perspectives, including inflammation with different durations (chronic and acute inflammation), different scopes (systemic and local inflammation) and different occurrence sequences (inflammation occurring after and before cancer). In addition, we also introduced bacteria/virus-based cancer immunotherapies. We perceive that inflammation may be a double-edged sword with cancer-promoting and cancer-suppressing functions in certain cases. We expect to further improve the understanding of the relationship between inflammation and cancer and provide a theoretical basis for further research on their complex interaction.

7.
Int Immunopharmacol ; 118: 110023, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36934562

RESUMEN

Intrauterine adhesion (IUA) is manifested by endometrial fibrosis and inflammation, which seriously affects female reproductive health. Macrophages are mainly inflammatory cells and have been reported to participate in the fibrosis of IUA. Oroxylin A (OA), a kind of flavonoid compounds, was showed to possess the inhibitory effects on inflammation and fibrosis. However, the role of OA in IUA remains unclear. In the present study, we found that OA effectively alleviated the level of inflammation and uterine fibrosis in IUA mice. OA also decreased the macrophage pyroptosis which increased in uteri of IUA mice. Pyroptosis is a programmed cell death accompanied by an inflammatory response. Moreover, OA repressed the mediators of pyroptosis including the expression of NOD-like receptor family pyrin domain containing 3 (NLRP3), caspase-1 and Gasdermin D (GSDMD) and the release of IL-1ß, IL-18 and cleaved-caspase-1 in J774A.1 cells induced by LPS/ATP in vitro. Mechanistically, the alleviation of OA on uterine fibrosis is achieved by inhibiting macrophage pyroptosis via SIRT3-SOD2-ROS pathway. Our data indicate that OA may serve as an effective agent for the treatment of the endometrial fibrosis with IUA.


Asunto(s)
Inflamasomas , Sirtuina 3 , Ratones , Femenino , Animales , Inflamasomas/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Sirtuina 3/metabolismo , Piroptosis , Macrófagos/metabolismo , Flavonoides/farmacología , Flavonoides/uso terapéutico , Caspasa 1/metabolismo , Inflamación/metabolismo , Fibrosis
8.
Chemosphere ; 313: 137536, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36528161

RESUMEN

The effective disposal of municipal solid wastes (MSW) and its incineration-derived fly ash (IFA), which contains large amounts of heavy metals (HMs) and chlorine (Cl), is an urgent task. In this study, IFA was used to reform MSW pyrolysis volatiles within 500-800 °C. The changes of reformed pyrolysis products, the migration characteristics of HMs and Cl between IFA and pyrolysis products were investigated. The results indicated that the O- and Cl-containing compounds in pyrolysis oil tended to decrease, light hydrocarbons and its calorific value increased accordingly after reforming; more CH4 and H2 gases were produced concurrently. The increase in reforming temperature enhanced these trends. The IFA absorbed Cl from volatiles during reforming, which reduced HCl in the gas product. The toxicity equivalent (TEQ) of PCDD/Fs in IFA decreased dramatically from 0.47 µg/kg to 0.0055 µg/kg after reforming at 500 °C, and it decreased with increasing reforming temperature. Some of the HMs' concentrations in the used IFAs increased, but their leaching capacity all decreased significantly at 800 °C except for Cr. The used IFA at 800 °C (IFA-800) corresponded to the lowest HMs leaching concentrations and could meet the landfill requirements; while the used IFA at 500 °C (IFA-500) corresponded to the maximum carbon deposition of 14.63 wt%, providing the energy source for its melting. Therefore 800 °C was recommended for harmless disposal of IFA, and 500 °C was better for a further melting of IFA., The contamination of pyrolysis liquid caused by inorganic Cl-containing compounds at 500 and 800 °C with much lower levels than the original. This study showed the hazardous properties of IFA can be dampened after interacting with MSW pyrolysis volatiles within the tested temperature range, and provided a good chance for the simultaneous disposal of IFA and recovery of high-quality MSW pyrolysis products.


Asunto(s)
Metales Pesados , Dibenzodioxinas Policloradas , Ceniza del Carbón , Residuos Sólidos , Incineración , Dibenzofuranos , Pirólisis , Dibenzodioxinas Policloradas/análisis , Metales Pesados/análisis , Gases , Cloro
9.
Front Psychiatry ; 13: 980516, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36465302

RESUMEN

Objective: The aim of the study was to investigate the clinical, neuropsychological, and regional cerebral blood flow (rCBF) perfusion changes in patients with neuropsychiatric symptoms caused by nitrous oxide (N2O) abuse. Methods: A total of 16 patients with neuropsychiatric symptoms caused by nitrous oxide abuse were recruited for this study. The study was carried out in the withdrawal phase of N2O abuse. A 925-1110 MBq 99mTc-ECD was administered intravenously. SPECT/CT images were collected with a low-energy and high-resolution collimator. The region uptake statistics of different brain regions of interest between patients with N2O abuse and normal people of the databases for younger subjects from the Scenium DB Comparison software were calculated automatically. Results: The clinical manifestations of the 16 patients with neuropsychiatric symptoms were mood lability, anxiety, hallucination, delusion, agitation, confusion, and other psychiatric symptoms. In addition, 15 of the patients also complained of memory decline; 14 patients manifested numbness or paresthesia; 14 patients developed limb weakness, and their motor impairments were more severe in the lower limbs than in the upper limbs; and eight patients had urinary and defecation disturbances. In the neuropsychological examination, the BPRS score was 54.69 ± 11.48, the HAMD score was 30.00 ± 11.06, the HAMA score was 18.06 ± 5.77, the MMSE score was 28.06 ± 2.29, and the MoCA score was 25.06 ± 3.40. SPECT showed hypoperfusion in the frontal and temporal lobes, which is consistent with the clinical findings. Conclusion: This was the first study to demonstrate the obvious effect of N2O abuse on CBF in patients with neuropsychiatric symptoms. CBF perfusion imaging is helpful to detect the changes in the local brain functional activity in patients with N2O abuse.

10.
Melanoma Res ; 32(6): 419-427, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36094494

RESUMEN

LS-007, an inhibitor of cyclin-dependent kinase 9 (CDK9), exhibits potential antitumor activity against chronic lymphocytic leukemia and ovarian cancer, but its effect on melanoma and tumor microenvironment (TME) has not been reported yet. This study aimed to investigate the role of LS-007 in B16F10 melanoma and relevant mechanisms. LS-007 significantly inhibited viability and induced apoptosis of B16F10 cells in a dose-dependent manner, which were accompanied with the increased ratio of Bax to Bcl-2 and decreased Mcl-1 mRNA level. Western blot analysis showed that LS-007 increased the expression of cleaved caspase-3 and poly ADP-ribose polymerase (PARP). Furthermore, flow cytometry analysis and qRT-PCR results showed that LS-007 treatment resulted in cell cycle arrest by changing cell cycle-related gene expression. Notably, in vivo evaluation showed that LS-007 significantly decreased the weight and volume of tumor and the expression of Ki67, promoted the expression of iNOS and inhibited the expression of CD206, suggesting that LS-007 might inhibit tumor growth by suppressing polarization of macrophages into tumor-associated macrophages (TAMs) in the TME. The increase in M1/M2 treated with LS-007 detected by flow cytometry hinted that macrophages were polarized towards an antitumor phenotype. In addition, LS-007 induced higher apoptotic rate of B16F10 cells when co-cultured B16F10 with BMDMs. LS-007 has inhibitory effects on B16F10 cells in vivo and in vitro via inducing apoptosis, cell cycle arrest, and changing macrophage function in the TME.


Asunto(s)
Melanoma , Neoplasias Cutáneas , Humanos , Melanoma/patología , Línea Celular Tumoral , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/metabolismo , Apoptosis , Puntos de Control del Ciclo Celular , Macrófagos/metabolismo , Ciclo Celular , Microambiente Tumoral
11.
Waste Manag ; 149: 114-123, 2022 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-35728475

RESUMEN

With the implementation of municipal solid wastes (MSW) source segregation collection policy, the combustible waste components are suitable for pyrolysis treatment to recover value-added energy such as gas or oil. In this research, the volatile compounds from MSW pyrolysis were reformed by the char obtained from the same process and the high-temperature flue gas (HTFG) of 1200 °C was supplying as heating resource and gasifying agent in a tailor-made experimental set-up. The final yields and properties of the syngas, char, and oil after reforming were investigated. Experimental studies showed that the composition of HTFG had a significant influence on the products. As the HTFG being CO2 and its flowrate increased from 0 to 4 L/min/(kgMSW), the energy share in the gas first increased from 8.29 to 15.1 MJ/(kgMSW) with a higher heat value (HHV) of 19.9 MJ/Nm3, then it decreased slightly with a further increase in the flowrate. However, as the HTFG was H2O or the model flue gas (consisting of CO2, H2O, O2 and N2), the higher flowrate always increased the energy share and cold gasification efficiency (CGE) in the gas products. Both CO2 and H2O participated the volatiles' reforming reactions and enhanced char gasification; while the volatiles' reforming inhibited char gasification. When the flowrate of the model flue gas increased from 0 to 12.04 L/min/(kgMSW), the oil and char yields decreased and the CGE increased to more than 75%, which was much higher than that from direct air gasification of MSW; moreover, the gas products had much higher HHVs. This research provides a guidance for producing high-quality syngas from the MSW.


Asunto(s)
Eliminación de Residuos , Residuos Sólidos , Dióxido de Carbono , Gases , Calefacción , Calor , Temperatura
12.
Int J Nanomedicine ; 16: 5675-5692, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34456564

RESUMEN

PURPOSE: Since immune cells in the tumor microenvironment (TME) can affect the development and progression of tumors, strategies modulating immune cells are considered to have an important therapeutic effect. As a TLR7/8 agonist, R848 effectively activates the innate immune cells to exert an anti-tumor effect. Mn2+ has been reported to strongly promote the maturation of antigen-presenting cells (APCs), thereby enhancing the cytotoxicity of CD8+ T cells. Thus, we tried to investigate whether chitosan-poly(acrylic acid) nanoparticles (CS-PAA NPs) loaded with R848 and MnCl2 (R-M@CS-PAA NPs) could exert an anti-tumor effect by regulating the function of immune cells. METHODS: R-M@CS-PAA NPs were prepared, and their basic characteristics, anti-tumor effect, and potential mechanisms were explored both in vitro and in vivo. RESULTS: R-M@CS-PAA NPs easily released MnCl2 and R848 at low pH. In B16F10 mouse melanoma model, R-M@CS-PAA NPs exerted the most significant anti-melanoma effect compared with the control group and CS-PAA NPs loaded with R848 or MnCl2 alone. FITC-labeled R-M@CS-PAA NPs were displayed to be accumulated at the tumor site. R-M@CS-PAA NPs significantly increased the infiltration of M1 macrophages and CD8+ T cells but reduced the number of suppressive immune cells in the TME. Moreover, in vitro experiments showed that R-M@CS-PAA NPs polarized macrophages into the M1 phenotype to inhibit the proliferation of B16F10 cells. R-M@CS-PAA NPs also enhanced the killing function of CD8+ T cells to B16F10 cells. Of note, R-M@CS-PAA NPs not only promoted the maturation of APCs such as dendritic cells and macrophages by STING and NF-кB pathways, but also enhanced the ability of dendritic cells to present ovalbumin to OT-I CD8+ T cells to enhance the cytotoxicity of OT-I CD8+ T cells to ovalbumin-expressing B16F10 cells. CONCLUSION: These data indicate that the administration of R-M@CS-PAA NPs is an effective therapeutic strategy against melanoma.


Asunto(s)
Quitosano , Melanoma , Nanopartículas , Resinas Acrílicas , Animales , Linfocitos T CD8-positivos , Células Dendríticas , Macrófagos , Ratones , Microambiente Tumoral
13.
Waste Manag ; 106: 77-87, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-32199229

RESUMEN

A technology of sewage sludge (SS) pyrolysis coupled with self-supplied steam reforming of the volatile is developed to utilize the latent heat of the steam vapor released in the SS drying & pyrolysis process. An integrated reactor consisting of a vertical free-falling pyrolysis section and a horizontal screw-moved reforming section is designed for this purpose. The performance of the reactor shows that by changing the moving speed of the char in the reforming section, high quality syngas with an H2/CO ratio of 4.37 and a percentage of H2 + CO up to 66.58 vol% can be obtained at approximately 570-600 °C for the dry SS. There is an optimum moving speed of the screw for producing the highest volume of the syngas. A higher moving speed of the screw also results in a higher concentration of the aromatic compounds in the final pyrolysis oil. When the initial moisture content of SS increases from 0 to 65.50%, the H2/CO ratio and H2/CO2 ratio in the syngas increase from 4.37 to 30.87 and from 2.1 to 2.6 correspondingly, and the final oil yield decreases from 24.03 wt% to 14.16 wt%. Moreover, the total energy recovery efficiency decreases from 88.85% to 61.92%, while the energy portion of syngas shows a peak of 44.18% of the total energy input when the initial moisture content is 41.26%. The integrated reactor also provides a good opportunity for adding a catalyst such as dolomite to make the process more effective. The technology developed in this paper provides an approach to deal with SS with a relatively high moisture content.


Asunto(s)
Aguas del Alcantarillado , Vapor , Gases , Calor , Pirólisis
14.
Waste Manag ; 102: 380-390, 2020 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-31733562

RESUMEN

The gas and oil product derived from municipal solid waste (MSW) pyrolysis was upgraded by utilizing the interaction between the volatile compounds and the char and the mechanism involved is explored. The influences of operation parameters, including interaction temperature, char/volatiles mass ratio (C/V) and gas hourly space velocity (GHSV) of the volatiles on the distribution and property of the upgraded products were investigated. The results showed that the higher interaction temperature, higher C/V and lower GHSV favored the conversion of condensable volatiles into gas products, thus increasing the gas yield in the outlet stream. The highest gas yield (44.14 wt%) was obtained at 700 °C with the natural C/V ratio (0.8) and GHSV, which was twice of the gas yield in the volatiles. The chemical energy portion of gas increased to 8065 kJ/kgMSW from 3209 kJ/kgMSW at this condition. Syngas with H2/CO molar ratio of around 2 can be obtained at 700 °C with C/V ratio of 0.8 or at 600 °C with higher C/V ratios (C/V = 1.5-2.2). Oxygenates and acidity of the reformed oil products decreased; but monoaromatics and light polyaromatics concentration increased greatly. Heavy polycyclic aromatic hydrocarbons (PAHs) in the liquid products were degraded after volatiles/hot char interaction. Suitable conditions can be varied and recommended for obtaining different desired high-quality products based on this process.


Asunto(s)
Pirólisis , Residuos Sólidos , Gases , Calor , Temperatura
15.
Curr Zool ; 64(6): 727-731, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30538732

RESUMEN

In many vertebrates, the brain's right hemisphere which is connected to the left visual field specializes in the processing of information about threats while the left hemisphere which is connected to the right visual field specializes in the processing of information about conspecifics. This is referred to as hemispheric lateralization. But individuals that are too predictable in their response to predators could have reduced survival and we may expect selection for somewhat unpredictable responses. We studied hemispheric lateralization in yellow-bellied marmots Marmota flaviventer, a social rodent that falls prey to a variety of terrestrial and aerial predators. We first asked if they have lateralized responses to a predatory threat. We then asked if the eye that they used to assess risk influenced their perceptions of risk. We recorded the direction marmots were initially looking and then walked toward them until they fled. We recorded the distance that they responded to our experimental approach by looking, the eye with which they looked at us, and the distance at which they fled (i.e., flight initiation distance; FID). We found that marmots had no eye preference with which they looked at an approaching threat. Furthermore, the population was not comprised of individuals that responded in consistent ways. However, we found that marmots that looked at the approaching person with their left eye had larger FIDs suggesting that risk assessment was influenced by the eye used to monitor the threat. These findings are consistent with selection to make prey less predictable for their predators, despite underlying lateralization.

16.
Environ Technol ; 38(13-14): 1689-1695, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27776447

RESUMEN

In this study, the municipal solid waste (MSW) is considered as one kind of energy source in urban planning scheme instead of a trash stream. Considering the characteristics of MSW from different urban functional zones and the current energy supply modes, an evaluation model for waste-to-energy (WtE) method was set up based on the analytical hierarchy process technique. The model consists of three layers: 15 fundamental indices, 4 influencing factors based on fundamental indices and the target functions supported by influencing factors. Taking an urban functional region of a city in north China as the research object, 4 alternatives are compared according to their weights and the sensitivities of the influencing factors are analyzed. The result will provide guide for the disposal method of WtE in new urban district planning and old urban redevelopment.


Asunto(s)
Fuentes Generadoras de Energía , Modelos Teóricos , Eliminación de Residuos/métodos , China , Ciudades , Planificación de Ciudades
17.
Biophys Physicobiol ; 13: 165-171, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27924271

RESUMEN

In mammals, bitter taste is mediated by TAS2Rs, which belong to the family of seven transmembrane G protein-coupled receptors. Since TAS2Rs are directly involved in the interaction between mammals and their dietary sources, it is likely that these genes evolved to reflect species-specific diets during mammalian evolution. Here, we analyzed the amino acids responsible for the difference in sensitivities of TAS2R16s of various primates using a cultured cell expression system. We found that the sensitivity of TAS2R16 varied due to several amino acid residues. Mutation of amino acid residues at E86T, L247M, and V260F in human and langur TAS2R16 for mimicking the macaque TAS2R16 decreased the sensitivity of the receptor in an additive manner, which suggests its contribution to the potency of salicin, possibly via direct interaction. However, mutation of amino acid residues 125 and 133 in human TAS2R16, which are situated in helix 4, to the macaque sequence increased the sensitivity of the receptor. These results suggest the possibility that bitter taste sensitivities evolved independently by replacing specific amino acid residues of TAS2Rs in different primate species to adapt to species-specific food.

18.
Waste Manag ; 58: 241-249, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27596943

RESUMEN

In this research morphological techniques were used to characterize dechlorination process of PVC when it is in the mixed waste plastics and the two important factors influencing this process, namely, the proportion of PVC in the mixed plastics and heating rate adopted in the pyrolysis process were investigated. During the pyrolysis process for the mixed plastics containing PVC, the morphologic characteristics describing PVC dechlorination behaviors were obtained with help of a high-speed infrared camera and image processing tools. At the same time emission of hydrogen chloride (HCl) was detected to find out the start and termination of HCl release. The PVC contents in the mixed plastics varied from 0% to 12% in mass and the heating rate for PVC was changed from 10 to 60°C/min. The morphologic parameters including "bubble ratio" (BR) and "pixel area" (PA) were found to have obvious features matching with PVC dechlorination process therefore can be used to characterize dechlorination of PVC alone and in the mixed plastics. It has been also found that shape of HCl emission curve is independent of PVC proportions in the mixed plastics, but shifts to right side with elevated heating rate; and all of which can be quantitatively reflected in morphologic parameters vs. temperature curves.


Asunto(s)
Plásticos/química , Cloruro de Polivinilo/química , Eliminación de Residuos/métodos , Halogenación , Calor , Ácido Clorhídrico/química , Residuos Sólidos
19.
BMC Cancer ; 16: 693, 2016 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-27577729

RESUMEN

BACKGROUND: To date, no guideline is proposed for elderly nasopharyngeal carcinoma (NPC) due to lack of prospective clinical trials. The present study comparing the survivals and toxicities in elderly NPC patients received either induction chemotherapy followed by radiotherapy(IC + RT) or concurrent chemoradiotherapy (CCRT) was therefore undertaken to provide a more accurate basis for future clinical practice. METHODS: The eligible elderly NPC patients were retrospectively enrolled. Propensity score matching generated a matched cohort (1:2) composed from CCRT and IC + RT groups. The survivals and treatment-induced toxicities were compared between two groups. Multivariable analysis was carried to identify significant prognostic factors. RESULTS: The 5-year overall survival, cancer-specific survival, locoregional failure-free survival, distant failure-free survival for all patients were 58.3 %, 62.7 %, 88.7 %, 83.0 %, respectively. No significant survival differences were found between CCRT and IC + RT groups in the propensity-matched cohort. In comparison with the patients who received IC + RT, patients who underwent CCRT were associated with more severe acute toxicities including leucopenia (30 % vs. 6.8 %, P = 0.005), anemia (20 % vs. 4.1 %, P = 0.027), mucositis (63.3 % vs. 34.2 %, P = 0.007), weight loss (23.4 % vs. 4.1 %, P = 0.009). Basicranial bone involvement was an independent prognostic factor that predicted all-cause death (HR = 0.553, 95 % CI 0.329-0.929; P = 0.025) and cancer specific death (HR = 0.558, 95 % CI 0.321-0.969; P = 0.038) in elderly patients. CONCLUSIONS: In the context of no guideline for elderly NPC, the present study suggested IC + RT should be a preferable modality compared with CCRT, with similar treatment outcomes but less acute toxicities.


Asunto(s)
Carcinoma/tratamiento farmacológico , Carcinoma/radioterapia , Quimioradioterapia/métodos , Neoplasias Nasofaríngeas/tratamiento farmacológico , Neoplasias Nasofaríngeas/radioterapia , Anciano , Anciano de 80 o más Años , Carcinoma/mortalidad , Quimioradioterapia/efectos adversos , Cisplatino/administración & dosificación , Cisplatino/efectos adversos , Supervivencia sin Enfermedad , Femenino , Fluorouracilo/administración & dosificación , Fluorouracilo/efectos adversos , Humanos , Quimioterapia de Inducción/efectos adversos , Quimioterapia de Inducción/métodos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/mortalidad , Puntaje de Propensión , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Resultado del Tratamiento
20.
Waste Manag ; 37: 116-36, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25700606

RESUMEN

Pyrolysis has been examined as an attractive alternative to incineration for municipal solid waste (MSW) disposal that allows energy and resource recovery; however, it has seldom been applied independently with the output of pyrolysis products as end products. This review addresses the state-of-the-art of MSW pyrolysis in regards to its technologies and reactors, products and environmental impacts. In this review, first, the influence of important operating parameters such as final temperature, heating rate (HR) and residence time in the reaction zone on the pyrolysis behaviours and products is reviewed; then the pyrolysis technologies and reactors adopted in literatures and scale-up plants are evaluated. Third, the yields and main properties of the pyrolytic products from individual MSW components, refuse-derived fuel (RDF) made from MSW, and MSW are summarised. In the fourth section, in addition to emissions from pyrolysis processes, such as HCl, SO2 and NH3, contaminants in the products, including PCDD/F and heavy metals, are also reviewed, and available measures for improving the environmental impacts of pyrolysis are surveyed. It can be concluded that the single pyrolysis process is an effective waste-to-energy convertor but is not a guaranteed clean solution for MSW disposal. Based on this information, the prospects of applying pyrolysis technologies to dealing with MSW are evaluated and suggested.

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