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1.
Nano Lett ; 23(1): 291-297, 2023 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-36563295

RESUMEN

Electrochemical conversion of CO2 into high-value-added chemicals has been considered a promising route to achieve carbon neutrality and mitigate the global greenhouse effect. However, the lack of highly efficient electrocatalysts has limited its practical application. Herein, we propose an ultrafast and green electric explosion method to batch-scale prepare spherical indium (In) nanocrystals (NCs) with abundant metal defects toward high selective electrocatalytic CO2 reduction (CO2RR) to HCOOH. During the electric explosion synthesis process, the Ar atmosphere plays a significant role in forming the spherical In NCs with abundant metal defects instead of highly crystalline In2O3 NCs formed under an air atmosphere. Analysis results reveal that the In NCs possess ultrafast catalytic kinetics and reduced onset potential, which is ascribed to the formation of rich metal defects serving as effective catalytic sites for converting CO2 into HCOOH. This work provides a feasible strategy to massively produce efficient In-based electrocatalysts for electrocatalytic CO2-to-formate conversion.

2.
Environ Sci Technol ; 56(14): 10299-10307, 2022 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-35767694

RESUMEN

The electrochemical nitrate reduction reaction (NITRR), which converts nitrate to ammonia, is promising for artificial ammonia synthesis at mild conditions. However, the lack of favorable electrocatalysts has hampered its large-scale applications. Herein, we report the batch-scale synthesis of three-dimensional (3D) porous Cu@Cu2O microspheres (Cu@Cu2O MSs) composed of fine Cu@Cu2O nanoparticles (NPs) using a convenient electric explosion method with outstanding activity and stability for the electrochemical reduction of nitrate to ammonia. Density functional theory (DFT) calculations revealed that the Cu2O (111) facets could facilitate the formation of *NO3H and *NO2H intermediates and suppress the hydrogen evolution reaction (HER), resulting in high selectivity for the NITRR. Moreover, the 3D porous structure of Cu@Cu2O MSs facilitates electrolyte penetration and increases the localized concentration of reactive species for the NITRR. As expected, the obtained Cu@Cu2O MSs exhibited an ultrahigh NH3 production rate of 327.6 mmol·h-1·g-1cat. (which is superior to that of the Haber-Bosch process with a typical NH3 yield <200 mmol h-1g-1cat.), a maximum Faradaic efficiency of 80.57%, and remarkable stability for the NITRR under ambient conditions. Quantitative 15N isotope labeling experiments indicated that the synthesized ammonia originated from the electrochemical reduction of nitrate. Achieving the batch-scale and low-cost production of high-performance Cu@Cu2O MSs electrocatalysts using the electric explosion method is promising for the large-scale realization of selective electrochemical reduction of nitrate toward artificial ammonia synthesis.

3.
Soft Matter ; 13(21): 3863-3870, 2017 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-28430268

RESUMEN

Self-folding of a pre-strained shape memory polymer (SMP) sheet was demonstrated using local joule heating. Folding is caused by shrinkage variation across the thickness of the SMP sheet. The folding direction can be controlled by the interfacial interaction between the heater and the SMP sheet. When the heater is placed on the SMP sheet with no constraint (weak interface), the SMP sheet folds toward the heater. Temperature gradient across the SMP thickness gives rise to the shrinkage variation. By contrast, when the heater is fixed to the SMP sheet (strong interface), the SMP sheet can fold away from the heater. In this case shrinkage variation is dictated by the constraining effect of the heater. In either mode, 180 degrees folding can be achieved. The folding angle can be controlled by varying the heater width and folding time. This method is simple and can be used to fold structures with sharp angles in a sequential manner. A variety of structures were folded as demonstrations, including digital numbers 0-9, a cube, a boat, and a crane.

4.
Histol Histopathol ; : 18743, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38639204

RESUMEN

BACKGROUND: Knee osteoarthritis (KOA) is a common chronic degenerative joint disease. 3D printing technology has become one of the important directions of medical development along with individualized precision treatment in orthopedics. OBJECTIVE: To investigate the effect of 3D printing technology-assisted total knee arthroplasty (TKA) on cartilage in rabbits with KOA. METHODS: A rabbit model of KOA was established and treated by TKA or 3D printing-assisted TKA. Four weeks after treatment, radiological evaluation of rabbit knees was performed by X-ray examination, in order to observe the severity of osteoarthritic lesions. Then the knee joints of rabbits were collected for Hematoxylin-eosin, Toluidine blue, and Safranin O-Fast green staining. The expressions of cartilage matrix metabolism-related and apoptosis-related genes were scrutinized by real-time quantitative reverse transcription-polymerase chain reaction, Western blot, and immunohistochemistry. The levels of inflammatory-related factors in the cartilage tissues of rabbits were tested by enzyme-linked immunosorbent assay. RESULTS: In rabbits with KOA, 3D printing technology-assisted TKA alleviated the inflammation and bone remodeling of the knee joint, relieved synovial hyperplasia and inflammatory cell infiltration in the articular cartilage, reduced articular cartilage degradation, suppressed cartilage matrix metabolism, and mitigated the inflammatory response and apoptosis of cartilage cells. CONCLUSION: 3D printing technology-assisted TKA exhibits a good treatment effect in rabbit KOA. This study provides an important basis for the clinical application of 3D printing technology-assisted TKA in KOA treatment.

5.
Nanoscale ; 14(17): 6671, 2022 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-35475460

RESUMEN

Correction for 'Soft electrothermal actuators using silver nanowire heaters' by Shanshan Yao et al., Nanoscale, 2017, 9, 3797-3805, https://doi.org/10.1039/C6NR09270E.

6.
Sci Adv ; 7(19)2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33952522

RESUMEN

Morphing structures are often engineered with stresses introduced into a flat sheet by leveraging structural anisotropy or compositional heterogeneity. Here, we identify a simple and universal diffusion-based mechanism to enable a transient morphing effect in structures with parametric surface grooves, which can be realized with a single material and fabricated using low-cost manufacturing methods (e.g., stamping, molding, and casting). We demonstrate from quantitative experiments and multiphysics simulations that parametric surface grooving can induce temporary asynchronous swelling or deswelling and can transform flat objects into designed, three-dimensional shapes. By tuning the grooving pattern, we can achieve both zero (e.g., helices) and nonzero (e.g., saddles) Gaussian curvature geometries. This mechanism allows us to demonstrate approaches that could improve the efficiency of certain food manufacturing processes and facilitate the sustainable packaging of food, for instance, by creating morphing pasta that can be flat-packed to reduce the air space in the packaging.

7.
ACS Macro Lett ; 9(8): 1119-1129, 2020 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-35653212

RESUMEN

Additive manufacturing (AM) with high-performance polymers (HPPs) represents simultaneously one of the most desirable and challenging feats in the AM arena. The very properties that make HPPs so attractive in a broad range of applications also make them nearly impossible to process using common AM equipment. Furthermore, when AM is achieved, it often brings the caveat of compromised mechanical properties of the final parts, in comparison with those made via injection molding. The demand to have advanced fabrication methods, rapid prototyping, and customization of parts while maintaining high performance in the finished products has inspired creative innovations that integrate chemical synthesis, materials science, mechanical engineering, and other fields into a multidisciplinary approach to advance AM with the seemingly "unprintable" HPPs. In this Viewpoint, we summarize several standout developments in the area and offer our perspective on future directions and challenges.

8.
Genet Mol Biol ; 32(1): 69-74, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21637648

RESUMEN

Several quantitative trait loci (QTL) for important reproductive traits (ovulation rate) have been identified on the porcine chromosome 15 (SSC15). To assist in the selection of positional candidate swine genes for these QTL on SSC15, twenty-one genes had already been assigned to SSC15 in a previous study in our lab, by using the radiation hybrid panel IMpRH. Further polymorphism studies were carried out on these positional candidate genes with four breeds of pigs (Duroc, Erhualian, Dahuabai and Landrace) harboring significant differences in reproduction traits. A total of nineteen polymorphisms were found in 21 genes. Among these, seven in six genes were used for association studies, whereby NRP2 polymorphism was found to be significantly (p < 0.05) associated with litter-size traits. NRP2 might be a candidate gene for pig-litter size based on its chromosome location (Du et al., 2006), significant association with litter-size traits and relationships with Sema and the VEGF super families.

9.
Nanoscale ; 9(11): 3797-3805, 2017 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-28134386

RESUMEN

Low-voltage and extremely flexible electrothermal bimorph actuators were fabricated in a simple, efficient and scalable process. The bimorph actuators were made of flexible silver nanowire (AgNW) based heaters, which exhibited a fast heating rate of 18 °C s-1 and stable heating performance with large bending. The actuators offered the largest bending angle (720°) or curvature (2.6 cm-1) at a very low actuation voltage (0.2 V sq-1 or 4.5 V) among all types of bimorph actuators that have been reported to date. The actuators can be designed and fabricated in different configurations that can achieve complex patterns and shapes upon actuation. Two applications of this type of soft actuators were demonstrated towards biomimetic robotics - a crawling robot that can walk spontaneously on ratchet surfaces and a soft gripper that is capable of manipulating lightweight and delicate objects.

10.
Am Heart J ; 152(3): 543.e1-5, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16923428

RESUMEN

BACKGROUND: Case-control studies have successfully identified many genetic associations for complex diseases but suffer from lack of reproducibility in the same population. Demonstrating weak genetic effect requires large sample sizes to minimize statistical bias. Based on a study examining 500 myocardial infarction (MI) patients and 500 controls from the genetically isolated Newfoundland population, we previously reported that thrombospondin-4 (THBS-4) 1186G>C variant associates with MI in women. To validate this sex-dependent association with the THBS-4 variant, we analyzed an additional 532 patients and 514 controls from the same population and the combined cohort consisting of 1032 patients and 1014 controls. METHODS: Genotyping of THBS-4 1186G>C was conducted using Taq Man 1186G>C (A3879P) (rs 1866389) genotyping technology on real-time polymerase chain reaction. RESULTS: The genotype distributions of THBS-4 1186G>C in the validation and combined cohorts were similar with those in our initial study, which supports genetic homogeneity in the studied population. The association of the CC genotype with MI in women (odds ratio [OR], 2.96; P = .008) reported in our initial cohort failed to achieve statistical significance in our validation cohort (OR, 1.53; P = .307) but was confirmed in the combined cohort (OR, 2.14; P = .009). In contrast to the results from the initial cohort was a significant association of the CC genotype with later onset MI in the validation (OR, 2.37; P = .029) and combined cohorts (OR, 2.22; P = .011). Moreover, the larger studied population gave statistical power to associate the CC genotype with risk of MI in the total patient population (OR, 1.58; P = .023). CONCLUSION: Homozygosity for the THBS-4 1186C variant is a weak risk factor for MI especially in older women.


Asunto(s)
Alelos , Infarto del Miocardio/genética , Polimorfismo Genético , Caracteres Sexuales , Trombospondinas/genética , Factores de Edad , Arginina/genética , Estudios de Cohortes , Femenino , Variación Genética/genética , Homocigoto , Humanos , Masculino , Persona de Mediana Edad , Prolina/genética , Factores de Riesgo , Tamaño de la Muestra
11.
Domest Anim Endocrinol ; 30(1): 1-16, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15970423

RESUMEN

The polymorphisms of 5' flanking region of chicken prolactin (cPRL) gene were examined in several populations of Chinese native Yuehuang, Taihe Silkie and imported White Leghorn Layer chickens. The 5' flanking regions (2638 bp) from Yuehuang, Taihe Silkie and White Leghorn chickens were subjected to sequencing analysis. Four single nucleotide polymorphisms (SNPs) were identified at position -2425(C/T), -2215(T/C), -2063(G/A) and -1967(A/G). A 24-bp indel (insertion or deletion) and a polyA length polymorphism were also identified. For the 24-bp indel locus, three genotypes (AA, AB and BB) were found in Yuehuang chickens, while only two genotypes were detected in Taihe Silkie (AB and BB) and Leghorn chickens (AA and BB). The genotype frequencies of AA, AB and BB were significantly different among the three breeds. For the polyA locus, although three genotypes (CC, CD and DD) were found, only one genotype (CC) was detected in White Leghorn chickens, while two or three genotypes were observed in Chinese native chickens. We used real-time quantitative PCR and radioimmunology assay to investigate the potential association of the 24-bp indel locus with cPRL mRNA expression, plasma cPRL and brooding behaviors, and observed that chickens with genotype AB, which are of the highest incidence of broodiness, had the highest cPRL mRNA levels, providing the possibility that this polymorphic site might be related to the broodiness in chickens via modulating the transcriptional level of cPRL gene. The dissociation among cPRL gene transcription, mRNA storage and hormone release was also observed.


Asunto(s)
Región de Flanqueo 5'/genética , Pollos/genética , Prolactina/genética , Animales , Secuencia de Bases , Variación Genética/genética , Genotipo , Datos de Secuencia Molecular , Polimorfismo de Nucleótido Simple/genética , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/veterinaria , Alineación de Secuencia
12.
Yi Chuan Xue Bao ; 32(4): 372-7, 2005 Apr.
Artículo en Zh | MEDLINE | ID: mdl-16011028

RESUMEN

Four breeds of chickens (White Leghorn, Yangshan, Taihe Silkies, White Recessive Rocks) with different egg production were applied to screen potential single nucleotide polymorphisms (SNPs) related to reproduction trait in distal part region of prolactin gene based on DNA pooling and sequencing. Eight SNPs (C2402T, T-2192C, C-2161G, C-2134G, C-2062G, G-2040A, A-1944G and C-1884A) were found successfully in the fragment of 1 028 bp at the distal part of 5'flanking region. Moreover,a simple and rapid method to estimate allelic frequencies of SNPs in each breed by calculating the ratio of allele peak heights was introduced here. The accuracies of estimation for the allelic frequencies of C-2402T, C-2161G, C-1884A, C-2062G and G-2040A were verified by comparing with the results of PCR-RFLP or PCR-SSCP.


Asunto(s)
Pollos/genética , ADN/genética , Polimorfismo de Nucleótido Simple , Prolactina/genética , Región de Flanqueo 5' , Animales , Secuencia de Bases , Pollos/clasificación , ADN/química , Frecuencia de los Genes , Genoma , Genotipo , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Polimorfismo Conformacional Retorcido-Simple , Sitios de Carácter Cuantitativo , Análisis de Secuencia de ADN
13.
Yi Chuan ; 27(2): 208-14, 2005 Mar.
Artículo en Zh | MEDLINE | ID: mdl-15843347

RESUMEN

Four chicken breeds (White Leghorn, Yangshan, Taihe Silkies, White Recessive Rocks) with different reproduction were applied to screen potential SNPs related to laying performance in the 5' flanking region, exon region and partial intron region of chicken prolactin (cPRL) gene. Totally almost 4500 bp were screened rapidly based on DNA pooling and sequencing, and thirteen single nucleotide polymorphisms (SNPs) and two indels (24 bp and 15 bp) were found, including nine SNPs and two indels in the 5' flanking region, one SNP in Exon 2, two SNPs in Exon 5 and one SNP in Intron 2 respectively. Furthermore, 5' flanking region of cPRL gene was analyzed by the website of http://motif.genome.ad.jp/. A possible Evi-1 binding site (score 93) was found in White Leghorn cPRL gene because of the 24 bp insertion, another possible C/EBPbeta binding site (score 94) was found in Yangshan cPRL gene because of the variation of C-2402T. Further studies need to be carried out to verify their effects on the expression of cPRL gene, the broodiness and laying performance of chickens.


Asunto(s)
Pollos/genética , Biología Computacional/métodos , Polimorfismo de Nucleótido Simple , Prolactina/genética , Región de Flanqueo 5' , Animales , Secuencia de Bases , Sitios de Unión/genética , Pollos/clasificación , Análisis Mutacional de ADN , Exones , Mutación INDEL , Intrones , Datos de Secuencia Molecular , Especificidad de la Especie , Factores de Transcripción/metabolismo
15.
Microbiology (Reading) ; 145 ( Pt 5): 1043-1048, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10376819

RESUMEN

Chemical changes of particular Bacillus subtilis spore components were monitored by attenuated total reflection Fourier-transform infrared spectroscopy (ATR/FTIR) during spore germination on a ZnSe internal reflection element. Within minutes of the initiation of spore germination, significant changes in the amount of calcium dipicolinate (DPA-Ca) and proteins were noted in the wild-type strain. The changes in a germination mutant (strain 1G9, gerD) were similar to those in the wild-type strain, but the rates of change were slower. The changes in another germination mutant (strain 1G7, gerA) were very different from those in the first two strains: germination was slow and incomplete, and proteins and DPA-Ca remained unaltered throughout the course of the germination study. This technique thus offers a sensitive and non-destructive method for real-time monitoring of various cellular components during spore germination.


Asunto(s)
Bacillus subtilis/fisiología , Esporas Bacterianas/química , Esporas Bacterianas/fisiología , Bacillus subtilis/genética , Calcio/análisis , Calcio/metabolismo , Mutación , Ácidos Picolínicos/análisis , Ácidos Picolínicos/metabolismo , Espectroscopía Infrarroja por Transformada de Fourier/métodos
16.
Genet. mol. biol ; 32(1): 69-74, 2009. tab
Artículo en Inglés | LILACS | ID: lil-505782

RESUMEN

Several quantitative trait loci (QTL) for important reproductive traits (ovulation rate) have been identified on the porcine chromosome 15 (SSC15). To assist in the selection of positional candidate swine genes for these QTL on SSC15, twenty-one genes had already been assigned to SSC15 in a previous study in our lab, by using the radiation hybrid panel IMpRH. Further polymorphism studies were carried out on these positional candidate genes with four breeds of pigs (Duroc, Erhualian, Dahuabai and Landrace) harboring significant differences in reproduction traits. A total of nineteen polymorphisms were found in 21 genes. Among these, seven in six genes were used for association studies, whereby NRP2 polymorphism was found to be significantly (p < 0.05) associated with litter-size traits. NRP2 might be a candidate gene for pig-litter size based on its chromosome location (Du et al., 2006), significant association with litter-size traits and relationships with Sema and the VEGF super families.


Asunto(s)
Animales , Sitios de Carácter Cuantitativo , Porcinos/genética , Tamaño de la Nidada , Reacción en Cadena de la Polimerasa , Polimorfismo Genético , Polimorfismo de Nucleótido Simple
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