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1.
Int J Biol Macromol ; 264(Pt 2): 130574, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38453125

RESUMEN

The prevalent use of disposable plastic tableware presents notable environmental and health risks. An alternative, polylactic acid (PLA), often does not meet usage requirements due to its low crystallization rate. This research introduces an amide-based nucleating agent, BRE-T-100, developed through a straightforward method to enhance the heat resistance and crystallization rate of PLA. This study systematically investigates the impact of BRE-T-100 and other nucleating agents on the properties of PLA composites. The incorporation of 0.8 % BRE-T-100 increases the crystallization temperature of PLA from 109.6 °C to 131.9 °C. Further, the total crystallization time of PLA composites at 120 °C is reduced to <60 s, while maintaining good transparency. BRE-T-100 exhibits superior comprehensive properties compared to talcum, TMC-200, and TMC-300 and is nearly on par with LAK-301. Its application as a nucleating agent in PLA-based disposable tableware shows promise.


Asunto(s)
Amidas , Calor , Poliésteres/química , Temperatura
2.
Mol Ecol Resour ; 24(5): e13950, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38567644

RESUMEN

Lignin, as an abundant organic carbon, plays a vital role in the global carbon cycle. However, our understanding of the global lignin-degrading microbiome remains elusive. The greatest barrier has been absence of a comprehensive and accurate functional gene database. Here, we first developed a curated functional gene database (LCdb) for metagenomic profiling of lignin degrading microbial consortia. Via the LCdb, we draw a clear picture describing the global biogeography of communities with lignin-degrading potential. They exhibit clear niche differentiation at the levels of taxonomy and functional traits. The terrestrial microbiomes showed the highest diversity, yet the lowest correlations. In particular, there were few correlations between genes involved in aerobic and anaerobic degradation pathways, showing a clear functional redundancy property. In contrast, enhanced correlations, especially closer inter-connections between anaerobic and aerobic groups, were observed in aquatic consortia in response to the lower diversity. Specifically, dypB and dypA, are widespread on Earth, indicating their essential roles in lignin depolymerization. Estuarine and marine consortia featured the laccase and mnsod genes, respectively. Notably, the roles of archaea in lignin degradation were revealed in marine ecosystems. Environmental factors strongly influenced functional traits, but weakly shaped taxonomic groups. Null mode analysis further verified that composition of functional traits was deterministic, while taxonomic composition was highly stochastic, demonstrating that the environment selects functional genes rather than taxonomic groups. Our study not only develops a useful tool to study lignin degrading microbial communities via metagenome sequencing but also advances our understanding of ecological traits of these global microbiomes.


Asunto(s)
Ecosistema , Lignina , Metagenómica , Microbiota , Lignina/metabolismo , Microbiota/genética , Microbiota/fisiología , Metagenómica/métodos , Archaea/genética , Archaea/clasificación , Archaea/metabolismo , Bacterias/clasificación , Bacterias/genética , Bacterias/metabolismo , Bacterias/aislamiento & purificación , Consorcios Microbianos/genética , Consorcios Microbianos/fisiología , Metagenoma
3.
Arab J Gastroenterol ; 24(4): 218-222, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37684149

RESUMEN

BACKGROUND AND STUDY AIMS: Balloon-occluded retrograde transvenous obliteration-assisted endoscopic cyanoacrylate injection (E-BRTO) temporarily treats gastric fundic varices draining through gastrorenal shunts (GRS) occluding the GRS with a balloon, then endoscopically injecting cyanoacrylate. We retrospectively examined the safety, feasibility, and efficacy of E-BRTO. PATIENTS AND METHODS: We enrolled 85 patients with hepatic cirrhosis plus gastric fundic varices with GRS; 34 underwent E-BRTO. The 51 patients who refused all secondary prophylactic treatments served as controls. RESULTS: Finally, 33 of the 34 patients underwent successful E-BRTO without major adverse events. Gastric varices were eradicated from all 33 patients in the E-BRTO group; the average follow-up time was 161.0 (74.0) weeks (mean [SD]). Four end-point events (12%) were recorded during the follow-up period. In the control group, 33 patients (65%) suffered repeat variceal bleeding, resulting in seven deaths. The cumulative rebleeding rates of the E-BRTO group on the 6th, 24th, 48th, 96th, 144th, 192nd, 240th, and 288th week were 0%, 3%, 9%, 9%, 13%, 13%, 13%, and 13%, while the cumulative rebleeding rates of the control group in the same period were 10%, 20%, 35%, 46%, 55%, 65%, 76%, and 76%. CONCLUSIONS: E-BRTO was safe, feasible, and well tolerated by patients with hepatic cirrhosis plus gastric fundic varices with GRS. Over the long-term follow-up period, the E-BRTO group demonstrated a lower rate of repeat bleeding than the control group.


Asunto(s)
Oclusión con Balón , Várices Esofágicas y Gástricas , Várices , Humanos , Várices Esofágicas y Gástricas/complicaciones , Várices Esofágicas y Gástricas/terapia , Cianoacrilatos , Hemorragia Gastrointestinal/etiología , Hemorragia Gastrointestinal/terapia , Estudios Retrospectivos , Resultado del Tratamiento , Oclusión con Balón/efectos adversos , Oclusión con Balón/métodos , Cirrosis Hepática/etiología , Várices/complicaciones , Várices/terapia
4.
J Colloid Interface Sci ; 606(Pt 2): 1205-1218, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34492459

RESUMEN

Flexible polyurethane foam (FPUF) is the most commonly used polyurethane, but its highly flammable characteristics makes it ignite easily and release a lot of heat and toxic gases. Here, the effect of different forms of copper salt modified graphene (rGO@CuO, rGO@Cu2O and rGO@CSOH) on improving the fire protection efficiency and mechanical property of FPUF is explored. Hybrid FPUF is characterized by thermogravimetric analysis (TGA), cone calorimeter, thermogravimetric analysis/Fourier transform infrared spectroscopy (TG-IR), tension, compression, and falling ball rebound testing. Compared with pure FPUF, the FPUF/rGO@CSOH show a significant decreasement in reducing the heat release of FPUF, the PHRR and THR are reduced by 36.9% and 29.4%, respectively. While the FPUF/rGO@Cu2O demonstrate excellent smoke and toxic gases suppression in FPUF, the PSPR and TSR are reduced by 24.6% and 51.9%, and the COP and COY are also reduced by 51.9% and 55.3%, respectively. After adding the copper salt hybrid, the buffering performance of FPUF did not change. Fortunately, the tensile and compressive strength increase obviously. The flame retardant and smoke suppression mechanism of hybrid FPUF has also been studied. This article gives a effective strategy for the preparation of FPUF with outstanding mechanical property, flame retardant and smoke suppression properties.


Asunto(s)
Retardadores de Llama , Grafito , Cobre , Poliuretanos
5.
Zhonghua Wai Ke Za Zhi ; 44(14): 952-5, 2006 Jul 15.
Artículo en Zh | MEDLINE | ID: mdl-17074202

RESUMEN

OBJECTIVE: To observe the feasibility of a segment thoracic esophagus replaced by using a nitinol alloy composite artificial esophagus. METHODS: A nitinol alloy composite artificial esophagus was made of a nitinol tube coated with a silicone membrane with a dacron flange 1 cm proximal to each end. There were ten pigs for the models of experimental animal. The models of experimental animal were established by excised a segment of 7 cm long thoracic esophagus and replaced with the graft. In accordance with the different anastomosis connective way 10 pigs were divided into group I and group II, every group had 5 pigs. In group I monolayer end-to-end anastomosis was used with this prosthesis. In group II monolayer end-to-end anastomosis was used with this prosthesis and above the site of anastomosis adding dacron strip fixed. After operation the operate animals were observed for eating and health. Esophagography and flexible esophagoscopy were performed once a month at the first, second, and third postoperatively month. Three pigs of the grafted prostheses sloughed out spontaneously at different postoperatively period were killed for autopsy and pathologic examination of the neoesophagus. RESULTS: All pigs had no leakage at the site of anastomosis and survived over 6 months. The longest survival was 20 months. Seven of 10 pigs the grafted prostheses sloughed out spontaneously at 2 to 6 months after the operation (4 in group I and 3 in group II). The grafted prostheses sloughed out spontaneously less than 3 months after operation, marked neoesophageal stenosis in the grafted portion was recognized (3 in group I). They displayed serious difficulty in eating. But the prostheses sloughed out spontaneously more than 3 months after operation, neoesophageal stenosis was increased slightly and the stenosis was only temporary and gradually resolved. (1 in group I, 3 in group II) They lived in good health and without difficulty in eating. Three of 10 pigs the grafted prosthesis still stayed in the grafted place over 10 months (1 in group I, 2 in group II). The neoesophageal had no stenosis. They were perfectly well in eating. CONCLUSIONS: A segment excised pig esophagus replaced with a nitinol alloy composite artificial esophagus is feasible and takes a better result.


Asunto(s)
Aleaciones , Órganos Artificiales , Esófago , Implantes Experimentales , Elastómeros de Silicona , Titanio , Animales , Materiales Biocompatibles , Esofagectomía , Femenino , Masculino , Diseño de Prótesis , Implantación de Prótesis , Porcinos , Factores de Tiempo
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