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1.
Sci Adv ; 7(35)2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34446433

RESUMEN

To achieve the goals of the post-2020 global biodiversity framework, we must identify representative targets that effectively protect biodiversity and can be implemented at a national level. We developed a framework to identify synergies between biodiversity and carbon across the Asian region and proposed a stepwise approach based on scalable priorities at regional, biome, and national levels that can complement potential Convention on Biological Diversity targets of protecting 30% land in the post-2020 global biodiversity framework. Our targets show that 30% of Asian land could effectively protect over 70% of all assessed species relative to only 11% now (based on analysis of 8932 terrestrial vertebrates), in addition to 2.3 to 3.6 hundred billion metric tons of carbon. Funding mechanisms are needed to ensure such targets to support biodiversity-carbon mutually beneficial solutions at the national level while reflecting broader priorities, especially in hyperdiverse countries where priorities exceed 30% of land.

2.
Biosci Rep ; 40(6)2020 06 26.
Artículo en Inglés | MEDLINE | ID: mdl-32588903

RESUMEN

BACKGROUND: The evidence for an association between the adiponectin gene (ADIPOQ) polymorphism rs182052 and cancer risk is inconsistent. We performed a meta-analysis to obtain more precise conclusions. METHODS: The PubMed, Embase, and Web of Science databases were searched until July 11, 2019. And seven epidemiology studies were retrieved, including 4,929 cases and 5,625 controls. Odds ratios (ORs) and the corresponding 95% confidence intervals (CIs) were calculated to evaluate the strength of the association. RESULTS: The meta-analysis demonstrated that rs182052 significantly increased the risk of cancer under the allele, homozygote, dominant, and recessive models, based on an overall analysis (A vs. G: OR, 1.09, 95% CI, 1.03-1.15, P=0.003; AA vs. GG: OR, 1.20, 95% CI, 1.07-1.34, P=0.002; AA+GA vs. GG: OR, 1.12, 95% CI, 1.03-1.22, P=0.010; AA vs. GA+GG: OR, 1.12, 95% CI, 1.01-1.23, P=0.025). In the stratified analysis by ethnicity, rs182052 significantly increased the cancer risk in both Asian and Caucasian populations under one or several genetic models. In the stratified analysis by cancer type, rs182052 significantly increased the risk of renal cell carcinoma (RCC) under the five models. CONCLUSIONS: Meta-analysis based on present studies suggests that rs182052 can increase the cancer risk.


Asunto(s)
Adiponectina/genética , Neoplasias/genética , Polimorfismo de Nucleótido Simple , Estudios de Casos y Controles , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Humanos , Neoplasias/diagnóstico , Neoplasias/etnología , Medición de Riesgo , Factores de Riesgo
3.
BMC Cancer ; 19(1): 1123, 2019 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-31744467

RESUMEN

BACKGROUND: The rs2057482 polymorphism in the hypoxia inducible factor 1 subunit alpha (HIF1A) gene has been reported to be associated with a risk of several types of cancer, but this association has not yet been definitively confirmed. We performed this meta-analysis to determine whether rs2057482 is associated with overall cancer risk. METHODS: The PubMed, Embase, and Web of Science databases were searched for the potential studies about the association between the rs2057482 and cancer risk. The data of genotype frequencies in cases with cancer and controls were extracted from the selected studies. Odds ratios (ORs) and the corresponding 95% confidence intervals (CIs) were calculated to determine the strength of the associations. RESULTS: The meta-analysis showed an association between the rs2057482 polymorphism and overall cancer risk. However, a stratified analysis of ethnicity did not show any significant association between rs2057482 and cancer risk in the Asian population. CONCLUSIONS: The rs2057482 polymorphism was associated with decreased overall cancer risk, based on the currently available studies. However, this conclusion needs verification by further well-designed epidemiology studies that examine different cancer types and more subjects.


Asunto(s)
Alelos , Predisposición Genética a la Enfermedad , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Neoplasias/genética , Polimorfismo de Nucleótido Simple , Estudios de Asociación Genética , Genotipo , Humanos , Oportunidad Relativa , Sesgo de Publicación
4.
ACS Appl Mater Interfaces ; 8(29): 18891-903, 2016 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-27362728

RESUMEN

In our quest to make various chemical processes sustainable, the development of facile synthetic routes and inexpensive catalysts can play a central role. Herein we report the synthesis of monodisperse, polyaniline (PANI)-derived mesoporous carbon nanoparticles (PAMCs) that can serve as efficient metal-free electrocatalysts for the hydrogen peroxide reduction reaction (HPRR) as well as the oxygen reduction reaction (ORR) in fuel cells. The materials are synthesized by polymerization of aniline with the aid of (NH4)2S2O8 as oxidant and colloidal silica nanoparticles as templates, then carbonization of the resulting PANI/silica composite material at different high temperatures, and finally removal of the silica templates from the carbonized products. The PAMC materials that are synthesized under optimized synthetic conditions possess monodisperse mesoporous carbon nanoparticles with an average size of 128 ± 12 nm and an average pore size of ca. 12 nm. Compared with Co3O4, a commonly used electrocatalyst for HPRR, these materials show much better catalytic activity for this reaction. In addition, unlike Co3O4, the PAMCs remain relatively stable during the reaction, under both basic and acidic conditions. The nanoparticles also show good electrocatalytic activity toward ORR. Based on the experimental results, PAMCs' excellent electrocatalytic activity is attributed partly to their heteroatom dopants and/or intrinsic defect sites created by vacancies in their structures and partly to their high porosity and surface area. The reported synthetic method is equally applicable to other polymeric precursors (e.g., polypyrrole (PPY)), which also produces monodisperse, mesoporous carbon nanoparticles in the same way. The resulting materials are potentially useful not only for electrocatalysis of HPRR and ORR in fuel cells but also for other applications where high surface area, small sized, nanostructured carbon materials are generally useful for (e.g., adsorption, supercapacitors, etc.).

5.
Dalton Trans ; 44(25): 11592-600, 2015 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-26041579

RESUMEN

Layered double hydroxide has been used in a variety of areas, including but not limited to catalysis, energy storage, drug or gene delivery, water treatment, etc. Herein, we report a new simple hydrothermal method to prepare a high surface area flower-like Ni-Fe layered double hydroxide (LDH) assembled by nanosheets by using nickel alkoxide and FeSO4 as the only starting materials. It is free of alkaline solution and other additives for directing or supporting in the synthesis procedure. The formation mechanism of this flower-like LDH formed by ultrathin nanosheets is also discussed. Moreover, the as-obtained LDH material shows increased electrocatalytic activity and stability toward WOR in alkaline media compared with the materials prepared without a Ni alkoxide precursor or Fe precursor, namely α-Fe2O3 and Ni(OH)2, respectively. In addition, the electrocatalytic activity is demonstrated to be related to the molar ratio of Fe and Ni in the final Ni-Fe material, and the best activity is achieved when the ratio reaches 0.52 : 1. The phase compositions of the resulting Ni-Fe(x) are discussed. Furthermore, the Ni-Fe LDH material reported herein might be employed as a promising noble-metal-free water oxidation catalyst to replace the IrOx material-the state-of-the-art water oxidation catalyst.

6.
Chem Commun (Camb) ; 50(21): 2755-7, 2014 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-24480810

RESUMEN

Stable reduced TiO2 rutile nanorods with well-defined facets were prepared by a solvothermal route in the presence of Zn powder. The oxygen vacancy in the TiO2 nanorods, which can be tuned by the amount of Zn, results in a narrow band gap and visible-light photocatalytic activity.


Asunto(s)
Nanotubos/química , Titanio/química , Catálisis , Luz , Microscopía Electrónica de Transmisión , Nanotubos/efectos de la radiación , Nanotubos/ultraestructura , Oxígeno/química , Procesos Fotoquímicos , Titanio/efectos de la radiación , Zinc/química
7.
Chem Commun (Camb) ; 49(84): 9788-90, 2013 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-24026044

RESUMEN

A synthetic route to prepare nanoporous Sr-rich strontium titanate (Sr : Ti ≈ 1.03) with a high surface area is reported. The as-obtained porous nanomaterial serves as a stable and superior photocatalyst for H2 evolution.

8.
Dalton Trans ; 42(40): 14357-60, 2013 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-23999901

RESUMEN

Wurtzite ZnO microspheres composed of radially aligned porous nanorods are prepared via a simple thermal treatment of a "pre-synthesized" zinc monoglycerolate precursor. The as-prepared hierarchical nanomaterial can serve as a highly sensitive sensing material for ethanol detection.

9.
Chem Commun (Camb) ; 49(54): 6087-9, 2013 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-23727666

RESUMEN

Graphene oxide nanoribbons (GONR) with regular edges have been prepared by a facile hydrothermal method. The relatively high yield and convenient preparation of GONR eventually make graphene nanoribbons (GNR) accessible in the field of composite materials where bulk quantities of nanoribbons are required.

10.
Dalton Trans ; 42(13): 4365-8, 2013 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-23420351

RESUMEN

Porous anatase TiO(2) microspheres composed of {010}-faceted nanobelts were synthesized through simple thermal treatment of a titanium glycerolate precursor. The as-prepared TiO(2) nanomaterial was shown to serve as an efficient photocatalyst for H(2) evolution, and its activity was more than twice that of the benchmark P25 TiO(2).

11.
Dalton Trans ; 41(32): 9773-80, 2012 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-22767327

RESUMEN

A W-containing inorganic-organic nanohybrid with a plate-like morphology has been successfully prepared through a nonaqueous synthetic route using WCl(6) as the tungsten source and benzyl alcohol as the solvent. The as-prepared hybrid nanomaterial was used directly as an efficient precursor for the formation of WO(3) nanoplates via a simple thermal treatment process. The as-obtained WO(3) material maintains the plate-like morphology of the precursor and possesses a unique uneven surface structure. It is noted that the use of a inorganic-organic hybrid precursor is essential for the creation of an uneven surface on the WO(3) nanoplates, which exhibit high sensitivity and selectivity for the detection of acetone vapour at a relatively low operating temperature (200 °C). The excellent sensing performance of the WO(3) nanomaterial is attributed to its unique uneven surface structure besides the small particle size and ultrathin morphology.

12.
Inorg Chem ; 50(18): 9106-13, 2011 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-21830761

RESUMEN

ZnS-CHA (CHA = cyclohexylamine) nanocomposite, a unique inorganic-organic hybrid semiconductor, has been prepared from a mild solvothermal reaction system. This material contains 2 nm-sized ZnS nanoparticles, and is photoactive toward UV light (≤300 nm). Under UV-irradiation, the ZnS-CHA nanocomposite is transformed to crystalline zinc hydroxysulfate nanosheets. The driving force of the light-driven transformation reaction is the photogeneration of charges (electrons and holes) in the ZnS nanoparticles, and these photogenerated charges interact with the CHA molecules and the inorganic S(2-) species, leading to decomposition of the organic component and self-oxidation of the inorganic ZnS nanoparticles to form zinc hydroxysulfate. Through simple thermal treatment, the as-formed zinc hydroxysulfate nanosheets are converted to ultrathin ZnO nanosheets with a porous feature, which exhibit high sensitivity and fast response and recovery for ethanol detection when used as an electrical sensing material.

13.
Shanghai Kou Qiang Yi Xue ; 17(4): 447-8, 2008 Aug.
Artículo en Chino | MEDLINE | ID: mdl-18784893

RESUMEN

A female patient, aged 59 years old, underwent immediate implantation of the abutment tooth attached by a magnet in an overdenture. The tooth recovered to normal three months later. A denture was remade and the tooth was still attached by a magnet at the same time. The overdenture fixed well 20 months later, and the tooth was normal. Results of X-ray examination was negative.


Asunto(s)
Pilares Dentales , Prótesis de Recubrimiento , Femenino , Humanos , Imanes , Persona de Mediana Edad
14.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 41(9): 559-62, 2006 Sep.
Artículo en Chino | MEDLINE | ID: mdl-17129432

RESUMEN

OBJECTIVE: This in vitro study was to evaluate the micro-tensile bond strength (microTBS) of three adhesives to sclerotic dentin in non-carious cervical lesions. METHODS: The maxillary premolars extracted due to periodontitis and with non-carious cervical lesions were collected. The non-carious, natural cervical sclerotic lesions were bonded with a total-etching adhesive Scotchbond Multi-Purpose, a two-step self-etching adhesive Contax, and an all-in-one self-etching adhesive Adper Prompt L-Pop. Artificially prepared wedge-shaped lesions were also made in sound premolars and bonded with the same adhesives as the controls. MicroTBS of these three adhesives was measured. RESULTS: MicroTBS of Scotchbond and Contax to sclerotic dentin was significantly lower than to normal dentin. But microTBS of Adper Prompt L-Pop to normal dentin was significantly lower than to sclerotic dentin. MicroTBS to sclerotic dentin was Scotchbond 46.805 MPa, Adper Prompt L-Pop 39.045 MPa, and Contax 29.852 MPa. CONCLUSIONS: In sclerotic dentin the microTBS was decreased because of the inferior micro-morphology of resin tags. Adhesives with low pH value might bond to sclerotic dentin effectively.


Asunto(s)
Recubrimientos Dentinarios/farmacología , Dentina/efectos de los fármacos , Resistencia a la Tracción/efectos de los fármacos , Abrasión de los Dientes/terapia , Cuello del Diente/patología , Bisfenol A Glicidil Metacrilato/farmacología , Resinas Compuestas/farmacología , Cementos Dentales/farmacología , Dentina/fisiología , Humanos , Técnicas In Vitro , Organofosfatos/farmacología , Cementos de Resina/farmacología
15.
Beijing Da Xue Xue Bao Yi Xue Ban ; 38(2): 204-6, 2006 Apr 18.
Artículo en Chino | MEDLINE | ID: mdl-16617368

RESUMEN

OBJECTIVE: To examine the effect of acid etching time on the bonding interface of non-carious cervical sclerotic dentin. METHODS: Twenty extracted premolars with non-carious cervical lesions were randomly divided into two groups, the lesion surface was conditioned with Scotchbond Multi-Purpose Plus dentin bonding system. The etching time was 15 s and 30 s respectively. The bonding interface ultrastructures were compared with SEM. RESULTS: In sclerotic dentin (15 s), the hybrid layer was visible, with minimal resin tags in the dentinal tubules and, when presented, they were shorter. Doubling the etching time (30 s) resulted in more resin tags with an hybrid layer formation on peritubular dentin. CONCLUSION: Doubling the etching time improved the ultrastructure of sclerotic dentin-resin bonding interface, and could be an efficient way to improve the bonding effect.


Asunto(s)
Grabado Ácido Dental/métodos , Recubrimiento Dental Adhesivo , Dentina Secundaria , Dentina Secundaria/patología , Humanos , Microscopía Electrónica de Rastreo , Factores de Tiempo , Cuello del Diente/patología
16.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 40(3): 230-2, 2005 May.
Artículo en Chino | MEDLINE | ID: mdl-15938888

RESUMEN

OBJECTIVE: To examine, in vitro study, the ultrastructure of resin-infiltrated sclerotic dentine following the application of a two-step self-etching dentin adhesive. METHODS: Non-carious, natural cervical sclerotic lesions were bonded using Contax (DMG Hamburg, Germany), a self-etching dentin adhesive. Artificially prepared wedge-shaped lesions were also made in sound bicuspids and bonded using the same adhesive as controls. By SEM examination, the morphological change of the dentin surface treated by Contax Primer, and the hybrid layer and resin tag in the dentin-resin interface were studied. RESULTS: Most dentinal tubules were occluded by rod-like sclerotic casts in the sclerotic dentin surface. Both hybrid layer and resin tag were observed in sclerotic dentin. The hybrid layer was almost similar to that in the sound dentin, but the resin tags were shorter than those in controls. CONCLUSIONS: Bonding to sclerotic dentin is different from sound dentin and may be compromised by occluded dentin tubules. Based on the present ultrastructural features of hybrid layer and resin tags, the Contax, a self-etching dentin adhesive with a low pH value primer, may have some bonding efficacy to sclerotic dentin.


Asunto(s)
Recubrimientos Dentinarios/farmacología , Dentina/ultraestructura , Cuello del Diente/ultraestructura , Dentina/efectos de los fármacos , Humanos , Microscopía Electrónica de Rastreo , Cuello del Diente/efectos de los fármacos
17.
Beijing Da Xue Xue Bao Yi Xue Ban ; 36(3): 319-21, 2004 Jun 18.
Artículo en Chino | MEDLINE | ID: mdl-15205709

RESUMEN

OBJECTIVE: To examine the ultrastructure of resin-infiltrated sclerotic dentine following the application of a three-step total-etching dentin adhesive. METHODS: Naturally-occurring, non-carious cervical lesions on extracted premolars were bonded using a total-etching dentin adhesive-Scotchbond Multi-purpose. Artificially prepared wedge-shaped lesions were also made in sound premolars and restored using the same adhesive as control. The morphological change of the dentin surface conditioned with the etchant, and the hybrid zone and resin tags in the dentin-resin interface were studied by SEM. RESULTS: Most dentinal tubules were obliterated by rod-like sclerotic casts in the non-carious cervical lesion, and could not be dissolved by Scotchbond Multi-purpose etchant. Both the hybrid zone and resin tags were observed in sclerotic dentin after restoration, although the resin tags were fewer and in lack of communications, the length of resin tags and the thickness of the hybrid zone were almost similar to those of the sound dentin. CONCLUSION: Bonding to sclerotic dentin is different from sound dentin, and may be compromised by the fewer resin tags and communications.


Asunto(s)
Grabado Ácido Dental , Recubrimiento Dental Adhesivo , Dentina Secundaria/ultraestructura , Recubrimientos Dentinarios/química , Humanos , Microscopía Electrónica de Rastreo
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