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1.
Dalton Trans ; 53(25): 10686-10692, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38864507

RESUMEN

By introducing the d0 metal cation Mo6+ into phosphates, two new molybdophosphates, K2MgMoP2O10 and K3Mg2MoP3O14, were synthesized by spontaneous crystallization, and their structures were determined by single-crystal X-ray diffraction. K2MgMoP2O10 shows a two-dimensional layer composed of the uncommon eight-membered ring [Mo2P2O16] formed by [MoO6] and [PO4], while K3Mg2MoP3O14 shows isolated [MoP3O14] clusters composed of [MoO5] and [PO4]. K2MgMoP2O10 and K3Mg2MoP3O14 have UV cut-off wavelengths of 277 and 271 nm, respectively, which are significantly shorter than those of most recently published molybdophosphates. To the best of our acknowledge, K2MgMoP2O10 exhibits the largest birefringence (a calculated value of 0.187 at 546 nm) among reported alkali metal or alkaline earth metal molybdophosphates, which provides a way to explore new birefringent materials. First-principles analysis of the electronic structure shows that the large birefringence of K2MgMoP2O10 mainly originates from the [MoO6] units.

2.
Inorg Chem ; 63(1): 272-279, 2024 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-38099743

RESUMEN

A new borophosphate, K2RbB8PO16 (KRBPO) was synthesized. It exhibits a bilayer structure consisting of two B-O layers with an 18-membered ring (18-MR) joined by [PO4], which is composed of the π-conjugated group [BO3] and non-π-conjugated groups [BO4] and [PO4]. The UV-vis-NIR diffuse reflectance spectroscopy shows that the cutoff edge is less than 200 nm. The calculation indicates that KRBPO exhibits moderate birefringence of 0.057@1064 nm, and the source of birefringence is mainly from the [BO3] groups.

3.
Dalton Trans ; 52(45): 16920-16926, 2023 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-37927065

RESUMEN

Two new selenites, K2Zn3Se4O12 (compound 1) and K4Zn3V4Se2O19 (compound 2), have been successfully synthesized by solid-state reactions in vacuum tubes. Compound 1 consists of a three-dimensional (3D) framework with [SeO3] triangular pyramids and [ZnO4] tetrahedra in the monoclinic space group P21/c (No. 14). Compound 1's cut-off edge is below 344 nm, based on its UV-Vis-NIR diffuse reflectance studies, and theoretical calculations indicate a birefringence of around 0.043 at 1064 nm. The two-dimensional layer of compound 2, in contrast, is made up of [SeO3] triangular pyramids, [ZnO4] tetrahedra, and [V4O13] tetrahedra. It crystallizes in the monoclinic space group C2/c (No. 15). Its UV-Vis-NIR diffuse reflectance studies demonstrate that the compound's cut-off edge is lower than 330 nm.

4.
Cell Mol Biol (Noisy-le-grand) ; 69(7): 158-163, 2023 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-37715390

RESUMEN

The formation of hypertrophic scar and keloid is considered to be a very complex pathological process. Our previous studies have shown that miR-15a-5p is an important miRNA in HTS tissues, and its expression level is significantly increased. Therefore, the potential mechanism of action of miR-15a-5p in scarring arouses our interest. This study preliminarily investigated the expression level of miR-15a-5p in HTS tissue and normal skin tissue and further explored the molecular mechanism. The results of this study once again confirmed that the expression level of miR-15a-5p was increased in HTS tissues and cells, and the closely related mRNA and protein levels of MyD88 and TGF-ß were also highly expressed. The relative expression levels of fibrosis-related indicators in HTsFb cells were up-regulated, such as collagen-Ⅰ, collagen-III and α-SMA. We constructed the HTS cell model and BALB/c nude animal model, and down-regulating miR-15a-5p, the HTsFb cells proliferation was inhibited, and qRT-PCR results showed that the fibrosis index mRNA was also reduced, and significantly reduce the pathological state of scar tissue. In conclusion, miR-15a-5p may participate in the formation and development of HTS through TLR/MyD88 signaling pathway and TGF-ß1 signaling pathway.


Asunto(s)
Cicatriz Hipertrófica , Queloide , MicroARNs , Animales , Ratones , Cicatriz Hipertrófica/genética , Queloide/genética , Receptor Toll-Like 4/genética , Factor 88 de Diferenciación Mieloide/genética , Proteínas Adaptadoras Transductoras de Señales , Ratones Desnudos , MicroARNs/genética , ARN Mensajero/genética
5.
J Plast Reconstr Aesthet Surg ; 75(10): 3743-3750, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36050219

RESUMEN

BACKGROUND: Extensive and complex contractures in the anterior knee area can pose a significant challenge for reconstruction due to insufficient skin and soft tissue coverage and poor cosmetic and functional outcomes using traditional methods. We presented our experience with pre-expanded muscle-sparing latissimus dorsi (LD) free flap as an alternative option for large-scale anterior knee reconstruction. METHODS: From January 2016 to December 2020, we applied this surgical technique in six patients with large postburn or post-traumatic contractures of the anterior knee. After tissue expansion of several months, the expanded muscle-sparing LD free flap was harvested and transferred to resurface the lesions. Operative procedures, postoperative complications, and long-term outcomes were evaluated. RESULTS: A total of six patients aged 7 to 32 years (mean: 20 years) were reconstructed successfully without any major complication. The flap ranged from 20 × 8 cm to 40 × 16 cm. All donor sites were primarily closed. Follow-up (range: 12 to 24 months) evaluation showed satisfactory results in both cosmetic and functional aspects. CONCLUSIONS: Pre-expanded muscle-sparing LD free flap is a reliable and effective choice for extensive anterior knee contracture reconstruction with satisfactory esthetic and functional outcome. It can provide substantial amount of soft tissue coverage with minimal complications and donor-site morbidity. Furthermore, it offers a good basis for next-step orthopedic surgery, such as total knee arthroplasty (TKA).


Asunto(s)
Contractura , Colgajos Tisulares Libres , Procedimientos de Cirugía Plástica , Músculos Superficiales de la Espalda , Contractura/etiología , Contractura/cirugía , Humanos , Procedimientos de Cirugía Plástica/métodos , Músculos Superficiales de la Espalda/trasplante , Expansión de Tejido , Resultado del Tratamiento
6.
Sci Total Environ ; 838(Pt 4): 156560, 2022 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-35690212

RESUMEN

The performances and reaction kinetics of the bamboo shoot leaves (BSL) pyrolysis were characterized integrating thermogravimetry, Fourier transform infrared spectroscopy, and pyrolysis-gas chromatography/mass spectrometry analyses. The high volatiles and low ash, N, and S contents of BSL rendered its pyrolysis suitable for bio-oil generation. The main mass loss of BSL pyrolysis occurred in the devolatilization stage between 200 and 550 °C. The peak temperatures of pseudo-hemicellulose, cellulose and lignin pyrolysis in BSL were 248.04, 322.65 and 383.51 °C, respectively, while their average activation energies estimated by Starink method were 144.29, 175.79 and 243.02 kJ/mol, respectively. The one-dimensional diffusion mechanism (f (α) = 1/(2α)) best elucidated the hemicellulose reaction. The cellulose (f (α) = 0.74 (1 - α)[-ln (1 - α)]-13/37) and lignin (f (α) = 0.35 (1 - α)[-ln (1 - α)]-13/7) reactions were best described by the nucleation mechanisms. The estimated kinetic triplets accurately predicted the pyrolysis process. 619.3 °C and 5 °C/min were determined as the optimal pyrolytic temperature and heating rate. The C-containing gases were dominant among the non-condensable gases evolved from the pyrolysis. The NOx precursors (NH3 and HCN) were found more important than NO emission in pollution control. 2,3-dihydrobenzofuran, (1-methylcyclopropyl) methanol, heptanal, acetic acid, and furfurals were the main pyrolytic by-products. BSL-derived biochar is a relatively pure carbon-rich material with extremely low N and S content. The BSL pyrolysis yielded a promising performance, as well as value-added by-products to be utilized in the fields of bioenergy, fragrance, and pharmaceuticals.


Asunto(s)
Lignina , Pirólisis , Biomasa , Celulosa , Gases/química , Cinética
7.
Appl Microbiol Biotechnol ; 100(9): 4161-75, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26711281

RESUMEN

Both planktonic and sediment bacterial assemblages are the important components of freshwater lake ecosystems. However, their spatiotemporal shift and the driving forces remain still elusive. Eutrotrophic Dianchi Lake and mesotrophic Erhai Lake are the largest two freshwater lakes on the Yunnan Plateau (southwestern China). The present study investigated the spatiotemporal shift in both planktonic and sediment bacterial populations in these two plateau freshwater lakes at different trophic status. For either lake, both water and sediment samples were collected from six sampling locations in spring and summer. Bacterioplankton community abundance in Dianchi Lake generally far outnumbered that in Erhai Lake. Sediment bacterial communities in Erhai Lake were found to have higher richness and diversity than those in Dianchi Lake. Sediments had higher bacterial community richness and diversity than waters. The change patterns for both planktonic and sediment bacterial communities were lake-specific and season-specific. Either planktonic or sediment bacterial community structure showed a distinct difference between in Dianchi Lake and in Erhai Lake, and an evident structure difference was also found between planktonic and sediment bacterial communities in either of these two lakes. Planktonic bacterial communities in both Dianchi Lake and Erhai Lake mainly included Proteobacteria (mainly Alpha-, Beta-, and Gammaproteobacteria), Bacteroidetes, Actinobacteria, Cyanobacteria, and Firmicutes, while sediment bacterial communities were mainly represented by Proteobacteria (mainly Beta- and Deltaproteobacteria), Bacteroidetes, Chlorobi, Nitrospirae, Acidobacteria, and Chloroflexi. Trophic status could play important roles in shaping both planktonic and sediment bacterial communities in freshwater lakes.


Asunto(s)
Bacterias/clasificación , Bacterias/aislamiento & purificación , Biota , Agua Dulce/microbiología , Lagos/microbiología , China , Sedimentos Geológicos/microbiología , Plancton/microbiología , Estaciones del Año , Análisis Espacio-Temporal
8.
J Environ Sci (China) ; 23 Suppl: S138-41, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25084576

RESUMEN

Aluminum electroplating layer on Q235 steel in AlCl3-NaCl-KCl molten salt was obtained, and the rule of its nucleation and growth were investigated. The results showed that aluminum electroplating layer formed through nucleating and growing of aluminum particles, and thickened by delaminating growth pattern. At low current density, the morphology of aluminum particles took on flake-like, while at high current density they changed to spherical. The thickness of plating layer increases with increasing current density and electroplating time. The relationship between the plating thickness (δ) and electroplating time (t) or current density (i) can be expressed as δ = 0.28f(137), and δ = 1.1i(1-39).


Asunto(s)
Aluminio/química , Galvanoplastia/métodos , Acero/química , Electricidad , Microscopía Electrónica de Rastreo , Factores de Tiempo
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