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Polysulfides are easily dissolved in the electrolyte of Li-S batteries after long cycles. Sn atom modification electrodes are beneficial for improving cycling stabilities of Li-S batteries. However, the influence of Sn atoms on the structure and electrochemical performance of SnO2/C composite materials is not explored. Sn/SnO2/C composite materials are developed as sulfur carriers in Li-S batteries in our work. In addition, the cycling stability mechanism of Sn/SnO2/C/S composite electrodes is also elucidated. Results show that introduced Sn/SnO2/C/S composite electrodes display good cycling stability (420.1 mAh·g-1 at 1C after 1000 cycles) in Li-S batteries. The sulfur load of Sn/SnO2/C/S composite electrodes is 80 wt % (2 mg-1·cm-2). The introduction of Sn into Sn/SnO2/C/S composite electrodes plays three roles. The first role is to enhance the structural stability of SnO2. The second role is to help adsorb active sulfur ions. The last role is to promote the electron transportation ability during the initial discharging/charging process. Sn/SnO2/C/S composite electrodes are beneficial for inhibiting the dissolution of polysulfides in electrolytes after long cycles.
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We proposed a new strategy for CO2 hydrogenation to prepare light olefins by introducing Zn into GaZrOx to construct ZnGaZrOx ternary oxides, which was combined with SAPO-34 to prepare a high-performance ZnGaZrOx/SAPO-34 tandem catalyst for CO2 hydrogenation to light olefins. By optimizing the Zn doping content, the ratio and mode of the two-phase composite, and the process conditions, the 3.5 %ZnGaZrOx/SAPO-34 tandem catalyst showed excellent catalytic performance and good high-temperature inhibition of the reverse water-gas shift (RWGS) reaction. The catalyst achieved 26.6 % CO2 conversion, 82.1 % C2 =-C4 = selectivity and 11.8 % light olefins yield. The ZnGaZrOx formed by introducing an appropriate amount of Zn into GaZrOx significantly enhanced the spillover H2 effect and also induced the generation of abundant oxygen vacancies to effectively promote the activation of CO2. Importantly, the RWGS reaction was also significantly suppressed at high temperatures, with the CO selectivity being only 46.1 % at 390 °C.
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Self-assembling peptides are valuable building blocks to fabricate supramolecular biomaterials, which have broad applications from biomedicine to biotechnology. However, limited choices to induce different globular proteins into hydrogels hinder these designs. Here, an easy-to-implement and tunable self-assembling strategy, which employs Ure2 amyloidogenic peptide, are described to induce any target proteins to assemble into supramolecular hydrogels alone or in combination with notable compositional control. Furthermore, the collective effect of nanoscale interactions among amyloid nanofibrils and partially disordered elastomeric polypeptides are investigated. This led to many useful macroscopic material properties simultaneously emerging from one pure protein material, i.e. strong adhesion to any substrates under wet conditions, rapidly self--assembling into robust and porous hydrogels, adaptation to remodeling processes, strongly promoting cell adhesion, proliferation and differentiation. Moreover, he demonstrated this supramolecular material's robust performance in vitro and vivo for tissue engineering, cosmetic and hemostasis applications and exhibited superior performance compared to corresponding commercial counterparts. To the best of his knowledge, few pure protein-based materials could meet such seemingly mutually exclusive properties simultaneously. Such versatility renders this novel supramolecular nanomaterial as next-generation functional protein-based materials, and he demonstrated the sequence level modulation of structural order and disorder as an untapped principle to design new proteins.
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Proteínas Amiloidogénicas , Proteínas de Insectos , Nanoestructuras , Péptidos/química , Nanoestructuras/química , Amiloide/química , Materiales Biocompatibles/química , Hidrogeles/químicaRESUMEN
Glycosylation can enhance the solubility and stability of flavonoids. The main limitation of the glycosylation process is low intracellular uridine diphosphate glucose (UDPG) availability. This study aimed to create a glycosylation platform strain in Escherichia coli BL21(DE3) by multiple metabolic engineering of the UDPG supply. Glycosyltransferase TcCGT1 was introduced to synthesize vitexin and orientin from apigenin and luteolin, respectively. To further expand this glycosylation platform strain, not only were UDP rhamnose and UDP galactose synthesis pathways constructed, but rhamnosyltransferase (GtfC) and galactosyltransferase (PhUGT) were also introduced, respectively. In a 5 L bioreactor with apigenin, luteolin, kaempferol, and quercetin as glycosyl acceptors, vitexin, orientin, afzelin, quercitrin, hyperoside, and trifolin glycosylation products reached 17.2, 36.5, 5.2, 14.1, 6.4, and 11.4 g/L, respectively, the highest titers reported to date for all. The platform strain has great potential for large-scale production of glycosylated flavonoids.
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Apigenina , Uridina Difosfato Glucosa , Glicosilación , Uridina Difosfato Glucosa/metabolismo , Apigenina/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Luteolina/metabolismo , Flavonoides/metabolismoRESUMEN
BACKGROUND: Blastocystis is one of the important zoonotic parasites which can infect humans and various animals worldwide and has become a growing global public health concern. The study aims to obtain the data of Blastocystis infection and the information of the genetic characteristic. METHODS: In the present study, 489 fecal samples were collected from diarrhea outpatients in Ningbo, Zhejiang province, and were examined the presence of Blastocystis by polymerase chain reaction combined with sequencing. RESULTS: A total of 10 samples (2.04%, 10/489) were positive for Blastocystis with no significant difference among sex and age groups, respectively. Eight samples were successfully sequenced, and five zoonotic ST3 and three zoonotic ST1 with two new sequences were identified. CONCLUSIONS: We first demonstrated the occurrence of Blastocystis infection in diarrhea outpatients in Ningbo, with two zoonotic subtypes (ST1 and ST3) and two new sequences being characterized. Meanwhile, mixed infection of Blastocystis and E. bieneusi was found which indicates the importance of investigation of multiple parasites. Finally, more extensive studies will be needed to better understand the transmission of Blastocystis at human-animal-environment interface and provide evidence for the development of one health strategies for the prevention and control of such diseases.
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Infecciones por Blastocystis , Blastocystis , Animales , Humanos , Infecciones por Blastocystis/epidemiología , Infecciones por Blastocystis/parasitología , Pacientes Ambulatorios , Variación Genética , Blastocystis/genética , China/epidemiología , Heces/parasitología , Diarrea/epidemiología , Prevalencia , FilogeniaRESUMEN
Enterocytozoon bieneusi, Cryptosporidium spp. and Cyclospora cayetanensis are three important zoonotic pathogens which were a major cause of foodborne or waterborne intestinal diseases in humans and animals. However, very little data about occurrence and genotypes of the three parasites in Ningbo in the south wing of the Yangtze River Delta, China, which is important for a tourist city. In the present study, molecular characterization of E. bieneusi, C. cayetanensis and Cryptosporidium spp. in fecal samples from 489 diarrheal outpatients were carried out. As a result, a total of 35 (7.16%, 35/489) and three (0.61%, 3/489) samples were positive for E. bieneusi and C. cayetanensis respectively. No Cryptosporidium-positive sample or mixed-infections were detected. Four known E. bieneusi genotypes (Type IV, D, I and CHN4) and 8 novel genotypes (NBH1-NBH8) were identified with type IV was the dominant genotype (n = 14), followed by genotypes D (n = 5), NBH8 (n = 5) and NBH7 (n = 3). The remaining genotypes were found in one sample each, and these genotypes were belonged to the previously described high-potential zoonotic group 1. One novel sequence named NBC315, and the other two sequences (NBC30 and NBC370) identical with the reported sequence were detected. Therefore, the existence and importance of zoonotic potential of E. bieneusi and C. cayetanensis in diarrheal outpatients in Ningbo indicates the public health threats, and more investigations should be carried out in human populations, animals and other environmental sources from the One Health perspective.
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Criptosporidiosis , Cyclospora , Enterocytozoon , Animales , Humanos , Enterocytozoon/genética , Cyclospora/genética , Pacientes Ambulatorios , China/epidemiología , Genotipo , Diarrea/epidemiología , Heces/parasitología , Filogenia , Criptosporidiosis/epidemiología , Criptosporidiosis/parasitología , PrevalenciaRESUMEN
Miniaturized and high-power-density 3D electronic devices pose new challenges on thermal management. Indeed, prompt heat dissipation in electrically insulating packaging is currently limited by the thermal conductivity achieved by thermal interface materials (TIMs) and by their capability to direct the heat toward heat sinks. Here, high thermal conductivity boron nitride (BN)-based composites that are able to conduct heat intentionally toward specific areas by locally orienting magnetically functionalized BN microplatelets are created using magnetically assisted slip casting. The obtained thermal conductivity along the direction of alignment is unusually high, up to 12.1 W m-1 K-1 , thanks to the high concentration of 62.6 vol% of BN in the composite, the low concentration in polymeric binder, and the high degree of alignment. The BN composites have a low density of 1.3 g cm-3 , a high stiffness of 442.3 MPa, and are electrically insulating. Uniquely, the approach is demonstrated with proof-of-concept composites having locally graded orientations of BN microplatelets to direct the heat away from two vertically stacked heat sources. Rationally designing the microstructure of TIMs to direct heat strategically provides a promising solution for efficient thermal management in 3D integrated electronics.
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Malonyl-CoA is an important building block for microbial synthesis of numerous pharmaceutically interesting or fatty acid-derived compounds including polyketides, flavonoids, phenylpropanoids and fatty acids. However, the tightly regulated intracellular malonyl-CoA availability often impedes overall product formation. Here, in order to unleash this tightly cellular behavior, we present evolution: dual dynamic regulations-based approaches to write artificial robust and dynamic function into intricate cellular background. Firstly, a conserved core domain based evolutionary principles were incorporated into genome mining to explore the biosynthetic diversities of discrete acetyl-CoA carboxylase (ACC) families, as malonyl-CoA is solely derived from carboxylation of acetyl-CoA by ACC in most organisms. A comprehensive phylogenomic and further experimental analysis, which included genomes of 50 strains throughout representative species, was performed to recapitulate the evolutionary history and reveal that previously unnoticed ACC families from Salmonella enterica exhibited the highest activities among all the candidates. A set of orthogonal and bi-functional quorum-sensing (QS)-based regulation tools were further designed and connected with T7 RNA polymerase as genetic amplifier to achieve dual dynamic control in a high dynamic range, which allowed us to efficiently activate and repress different sets of genes dynamically and independently. These genetic circuits were then combined with ACC of S. enterica and CRISPRi system to reprogram central metabolism that rewired the tightly regulated malonyl-CoA pathway to a robust and autonomous behavior, leading to a 29-fold increase of malony-CoA availability. We applied this dual regulation tool to successfully synthesizing malonyl-CoA-derived compound (2S)-naringenin, and achieved the highest production (1073.8 mg/L) reported to date associate with dramatic decreases of by-product formation. Notably, the whole fermentation presents as an autonomous behavior, totally eliminating human supervision and inducer supplementation. Hence, the constructed evolution: dual dynamic regulations-based approaches pave the way to develop an economically viable and scalable procedure for microbial production of malonyl-CoA derived compounds.
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Malonil Coenzima A , Policétidos , Acetilcoenzima A/genética , Acetil-CoA Carboxilasa , Ingeniería MetabólicaRESUMEN
Orientin and vitexin are flavone 8-C-glycosides that exhibit many biological characteristics. This study aimed to establish a two-enzyme-coupled catalytic strategy to enhance the biosynthesis of orientin and vitexin from apigenin and luteolin, respectively. The C-glucosyltransferase (TcCGT1) gene from Trollius chinensis was cloned and expressed in Escherichia coli BL21(DE3). The optimal activity of TcCGT1 was achieved at pH 9.0 and 37 °C. TcCGT1 was relatively stable over the pH range of 7.0-10.0 at a temperature lower than 45 °C. The coupled catalytic strategy of TcCGT1 and different sucrose synthases was adopted to enhance the production of orientin and vitexin. By optimizing the coupling reaction conditions, orientin and vitexin production successfully achieved 2324.4 and 5524.1 mg/L with a yield of 91.4 and 89.3% (mol/mol), respectively. The coupled catalytic strategy proposed in this study might serve as a promising candidate for the large-scale production of orientin and vitexin in the future.
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Apigenina , Luteolina , Catálisis , Flavonoides , Glucósidos , Glucosiltransferasas/genética , GlicosiltransferasasRESUMEN
Graphitic carbon nitride (g-C3N4) has emerged as a most promising photocatalyst, non-toxicity and low density, but it is plagued by low activity due to the small specific surface area and poor quantum efficiency. Morphological engineering and coupling with other materials to form hybrids have proven to be effective strategies for enabling high photocatalytic performances. Here, neodymium oxide (Nd2O3) coupled tubular g-C3N4 composites had been facilely synthesized by a solvent evaporation and high-temperature calcination method to realize efficient photocatalytic activity of hydrogen production and NO removal. A series of characterizations, such as XRD, ESR, in-situ DRIFTS, etc., were used to analyze the physical and chemical properties of the bifunctional photocatalyst, which demonstrated that the composite material had more active sites and a faster electron transfer rate. The optimal sample (1 wt% Nd2O3/CN-T) had a H2 generation rate of 4355.34 µmol·g-1·h-1, which was 9.46 times than that of original g-C3N4 obtained through heating melamine (CN-M). In addition, the NO removal rate was also 32.32% higher than that of original CN-M. On the basis of the above photocatalytic experimental results and characterizations, a possible mechanism or pathway was proposed and illustrated. This work could provide a feasible strategy to fabricate tubular g-C3N4-based composites with rare earth metal oxides (dual-factor regulation) to simultaneously enhance photocatalytic hydrogen production and NO removal efficiently (double application).
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Background: Essential hypertension is a multifactorial disease with high morbidity. The researches on the influence of genes on the disease are still in its infancy, and the mechanism of gene regulation is not clear. MiRNAs are key molecules that regulate the expression control of protein-coding or protein-non-coding RNA. It may be an important biological molecule risk factor for essential hypertension.Methods: A case-control study with 98 EH and 98 non-EH was conducted in our experiment. The candidate miRNAs including miR-10a-5p and miR-497-5p were detected and verified by qRT-PCR.Results: The expression level of miRNA in EH cases was significantly lower than the healthy control (P = 0.005). In addition, the relative expression of miR-10a-5p was closely positive correlated with DBP (r = 0.162, P = 0.023) and SBP (r = 0.223, P = 0.002). After adjusting confound factors, the result of the logistic regression indicated that hypo-expression of miR-10a-5p is a risk factor for EH (OR(95%CI) = 1.676(1.302,2.157), adjusted P < 0.0001). And the ROC analysis shows that the combined line with BMI and miR-10a-5p was a values marker for EH (AUC: 0.728, P < 0.0001).Conclusions: Lower expression of miR-10a-5p, as the key role, is significantly related to the risk of EH and maybe as a potential biomolecule for EH.
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Hipertensión Esencial/genética , MicroARNs/genética , Anciano , Área Bajo la Curva , Biomarcadores , Estudios de Casos y Controles , Femenino , Regulación de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Curva ROC , Factores de RiesgoRESUMEN
The refractive index of blood is a key biophysical parameter, which can reflect the physiological state. We measured the refractive index of whole blood and other components, such as serum, plasma, and hemoglobin, based on internal reflection by using a homemade apparatus in the spectral range of 400 to 750 nm. In addition to the hemoglobin solution, which has a Soret band about 420 nm and two Q-bands between 500 and 600 nm, the measurements of other samples are the normal dispersion curve. The results are approximated by the Cauchy equation and Sellmeier equation, and the correlation coefficients are more than 0.997.
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Análisis Químico de la Sangre/métodos , Refractometría/métodos , Animales , Análisis Químico de la Sangre/instrumentación , Diseño de Equipo , Hemoglobinas/análisis , Humanos , Masculino , Oxígeno/sangre , Conejos , Refractometría/instrumentaciónRESUMEN
Complex refractive index dispersion (CRID) of offset inks is an important spectral property that affects the quality of printing. Due to the strong absorption of offset inks, great difficulty exists when measuring their CRID. In this study, a recently proposed apparatus that can detect the internal reflectance spectra was used to measure the CRID of three strong absorbing offset inks (magenta, yellow, and cyan). Both anomalous dispersion curve and extinction coefficient curve were well determined over the spectral range of 400-750 nm. This study experimentally proves that the apparatus and related method are feasible for the CRID measurement of strong absorbing materials and could serve as a powerful measuring tool for optical parameters.
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BACKGROUND: Essential hypertension (EH) is a high prevalence with multifactorial diseases. Human studies on the impact of genes on this disease are just in the initial stage, the mechanism of gene regulation is still remains unclear. Circular RNAs (circRNAs) as a continuous cycle of covalent closure, RNA molecules added to the 3'-5' end covalently bound by the formation of incidental event. CircRNAs may be an important biomolecule in revealing the molecule regulate mechanisms of EH. METHODS: The circRNAs were selected and validated with qRT-PCR followed. Our experiment was conducted with case-control studies among 200â¯EH participants. The t-test was used to evaluate the different expression of circRNAs and miRNAs, the significance of which was set as pâ¯<â¯0.05. RESULTS: The hsa_circ_0037911 expression level in EH cases were significantly higher than healthy controls (pâ¯=â¯0.005). There was still important significance when adjusted by logistic regression (adjusted pâ¯=â¯0.026). We also found that hsa_circ_0037911 was an effective marker of EH (area under curveâ¯=â¯0.627; pâ¯=â¯0.002). The levels of hsa_circ_0037911 were significantly differences in gender, BMI, smoking and drinking among EH cases. There was a positive correlation between Serum creatinine (Scr) and hsa_circ_0037911. CONCLUSIONS: Our findings suggested that higher expression hsa_circ_0037911 may be key circRNAs for EH development by changing the concentration of Scr and could be a stable biomarker for early diagnosis of EH.
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Hipertensión Esencial/genética , ARN/genética , Adulto , Anciano , Estudios de Casos y Controles , Hipertensión Esencial/epidemiología , Femenino , Regulación de la Expresión Génica , Humanos , Masculino , MicroARNs/genética , Persona de Mediana Edad , ARN Circular , Factores de Riesgo , TranscriptomaRESUMEN
(1) The objective of this study was to assess the risk perceptions, attitudes, knowledge, and behaviors related to typhoon among rural residents in Zhejiang province of China. A cross-sectional study was conducted among rural residents in Zhejiang province, China. Information was collected from 659 participants using a structured questionnaire. Univariate analysis and multivariable analysis were used to analyze the data. Participants were most concerned about property damage, followed by their health and life. Television, short message service (SMS), relatives and friends were the most common information sources. Most people had not been educated with disaster prevention measures. The complementary log-log (CLL) model showed that understanding typhoon warning signal, preparation time, risk perception of health damage and life threat, and fears of typhoon were independent predictors of adoption of coping behaviors. We found that: 1. Residents' risk perception of health and life threat caused by typhoon is inadequate; 2. There is a gap between residents' cognition or knowledge and behavior in rural areas; 3. The government should further make strategies to develop educational activities, in order to eliminate the gap and improve the ability of preparing for typhoon among rural residents.
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Actitud , Tormentas Ciclónicas , Conocimiento , Población Rural , Adaptación Psicológica , Adulto , Anciano , China , Estudios Transversales , Femenino , Estado de Salud , Humanos , Masculino , Persona de Mediana Edad , Percepción , Factores de Riesgo , Adulto JovenRESUMEN
We report the quantitative refractive index (RI) imaging of cocultured cells in their living environment by scanning focused refractive index microscopy (SFRIM). Mouse microglial cells and synovial cells are cocultured on the top surface of a trapezoid prism. The RI imaging of living cells is obtained in a reflection-type method. The RI information is deduced with the simple derivative total internal reflection method, where a complex retrieval algorithm or reconstruction process is unnecessary. The outline of each cell is determined according to the RI value compared with that of the immersion liquid. The cocultured cells can be discriminated in the RI image. The measurement is nondestructive and label-free. The experimental results prove that SFRIM is a promising tool in the field of biological optics.
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Microglía/citología , Microscopía , Imagen Óptica/métodos , Líquido Sinovial/citología , Animales , Técnicas de Cocultivo , Ratones , RefractometríaRESUMEN
We present the application of scanning focused refractive index microscopy in the complex refractive index measurement of turbid media. An extra standard scattering layer is placed in front of the detector to perform scattering transformation on the reflected light. The principle of the scattering transformation is elaborated theoretically. The influence of the sample scattering is deeply and effectively suppressed experimentally. As a proof of the feasibility and accuracy of the proposed method, we demonstrate experimental data of 20% and 30% Intralipid solutions that are commonly used as phantom media for light propagation studies.
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OBJECTIVE: To study and explore the relativity of adults HBV vicinal failure and HLA-DR, T cell subset, trace viruses infection. To accumulate date for formulating preventing adult HBV infection prophylactic-therapeutic measures. METHODS: Select 20 adults randomly who had vaccinated with 10 microgYDV and produced anti-HBS successfully, and another 20 hadn't produced anti-HBs to form two groups-defeated group and contral group. Blood samples from two groups were taken for detecting the level of DR range gene phenotype: T cell subset, white blood cell HLA-DR, HLA-B27, HLA DRB1 * 07, DRB1* 04, DRB1 * 1001, DQB1 * 0401 and so on. RESULTS: The level of CD4(-)/CD8(-) is lower in the infection group than in healthy group. But the average level of HLA-DR and HLA-B27 is higher in the infection group. The differences of HLA DRB1 * 07 gene frequency between two groups were significant (P <0.05), but the levels of CD3, CD4, CD8, CD7, CD4/CD8 and HLA DRB1 * 04, DRB1 * 1001, DQB1 * 0401 were not significant. CONCLUSION: The failure of HBV vaccination on adults may have relation to HLA-DR, HLA-B27, HLA DRB1 * 07, CD4(-)/CD8(-), etc.