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1.
Proc Natl Acad Sci U S A ; 119(1)2022 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-34969860

RESUMEN

Mixed matrix membranes (MMMs) are one of the most promising solutions for energy-efficient gas separation. However, conventional MMM synthesis methods inevitably lead to poor filler-polymer interfacial compatibility, filler agglomeration, and limited loading. Herein, inspired by symbiotic relationships in nature, we designed a universal bottom-up method for in situ nanosized metal organic framework (MOF) assembly within polymer matrices. Consequently, our method eliminating the traditional postsynthetic step significantly enhanced MOF dispersion, interfacial compatibility, and loading to an unprecedented 67.2 wt % in synthesized MMMs. Utilizing experimental techniques and complementary density functional theory (DFT) simulation, we validated that these enhancements synergistically ameliorated CO2 solubility, which was significantly different from other works where MOF typically promoted gas diffusion. Our approach simultaneously improves CO2 permeability and selectivity, and superior carbon capture performance is maintained even during long-term tests; the mechanical strength is retained even with ultrahigh MOF loadings. This symbiosis-inspired de novo strategy can potentially pave the way for next-generation MMMs that can fully exploit the unique characteristics of both MOFs and matrices.

2.
Opt Express ; 32(4): 5011-5021, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38439238

RESUMEN

Semiconductor disk lasers can produce high output power and good beam quality simultaneously. The high intracavity circulating power of about hundreds of watts, along with the flexibility of tailorable emitting wavelengths, make it an attractive light source for obtaining ultraviolet (UV) radiation from near-infrared lasers through nonlinear frequency conversion. This work reports a frequency tripled 327 nm semiconductor disk laser with record output power and wavelength tuning range by using a type-I phase-matched LiB3O5 (LBO) crystal and a type-I phase-matched ß-BaB2O4 (BBO) crystal as the frequency-doubling and -tripling crystals respectively. Thanks to the obviously larger nonlinear coefficient of the type-I phase-matched BBO compared to the commonly used type-II phase-matched LBO, as well as the small spot size specifically designed at the crystal location, the maximum output power of UV lasers reaches 538 mW, corresponding to an optical-to-optical conversion efficiency from pump to UV laser of about 1.14%. A wavelength tuning range of about 8.6 nm and good power stability with a standard deviation of about 0.94 are also achieved.

3.
Phys Rev Lett ; 132(1): 010602, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38242678

RESUMEN

As a hybrid of artificial intelligence and quantum computing, quantum neural networks (QNNs) have gained significant attention as a promising application on near-term, noisy intermediate-scale quantum devices. Conventional QNNs are described by parametrized quantum circuits, which perform unitary operations and measurements on quantum states. In this Letter, we propose a novel approach to enhance the expressivity of QNNs by incorporating randomness into quantum circuits. Specifically, we introduce a random layer, which contains single-qubit gates sampled from a trainable ensemble pooling. The prediction of QNN is then represented by an ensemble average over a classical function of measurement outcomes. We prove that our approach can accurately approximate arbitrary target operators using Uhlmann's theorem for majorization, which enables observable learning. Our proposal is demonstrated with extensive numerical experiments, including observable learning, Rényi entropy measurement, and image recognition. We find the expressivity of QNNs is enhanced by introducing randomness for multiple learning tasks, which could have broad application in quantum machine learning.

4.
Sleep Breath ; 28(2): 1019-1033, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38147286

RESUMEN

OBJECTIVE: Sleep disorders such as insomnia, apnea, and restless leg syndrome can negatively affect a person's overall health and may cause hypertension, heart failure, and coronary heart disease. Likewise, periodontitis, a gum disease, can lead to both physical and psychological health issues, exerting a considerable effect on one's overall well-being-periodontitis stands as a primary cause of tooth loss. Nevertheless, there has been insufficient research on the correlation between the amount of sleep individuals get and the occurrence of periodontitis/tooth loss among Americans. Therefore, this study aimed to assess the influence of sleep length on periodontitis in the American population. METHODS: Periodontitis severity was classified (none, mild, moderate, and severe) using American Periodontal Association criteria. Sleep duration was assessed by self-reported data and categorized into three groups (deficient, adequate, and excessive). Tooth loss was assessed by the oral examination. To establish a connection between the duration of sleep and periodontitis/tooth loss, a weighted multivariable logistic regression analysis was employed. A GAM analysis and smooth curve fitting assessment were conducted to identify non-linear relationships. Subgroup, interaction, and mediation analyses were also performed. RESULTS: The prevalence of tooth loss was significantly high, affecting 96.4% of the individuals, whereas 46.6% of the study sample experienced moderate to severe periodontitis. The average age of participants was 52.7 years. After adjusting for potential confounding factors, the analysis of weighted multivariable logistic regression revealed a significant association between sleep insufficiency and moderate/severe periodontitis (OR 1.15, 95% CI 1.01-1.30, P = 0.0298), as well as tooth loss (OR 1.16, 95% CI 1.01-1.33, P = 0.0371). Additionally, the research showed a correlation between the length of sleep and periodontitis that followed a U-shaped pattern. In addition, the analysis of mediation revealed that high blood pressure explained 7.0% (95% CI 4.0% to 12.9%; P < 0.0001) of the link between the amount of sleep and the likelihood of losing teeth. CONCLUSION: Sleep duration was independently correlated with moderate/severe periodontitis/tooth loss and had a non-linear relationship.


Asunto(s)
Encuestas Nutricionales , Periodontitis , Pérdida de Diente , Humanos , Pérdida de Diente/epidemiología , Femenino , Masculino , Periodontitis/epidemiología , Periodontitis/diagnóstico , Persona de Mediana Edad , Adulto , Estados Unidos/epidemiología , Anciano , Sueño/fisiología , Trastornos del Sueño-Vigilia/epidemiología , Trastornos del Sueño-Vigilia/diagnóstico , Factores de Tiempo , Duración del Sueño
5.
J Med Virol ; 95(5): e28784, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37219044

RESUMEN

Several studies have shown a possible correlation between gut microbiota and COVID-19. However, the cause-and-effect relationship between the two has not been investigated. We conducted a two-sample Mendelian randomization study (MR) study using publicly available GWAS data. Inverse variance weighted (IVW) analysis was the main MR analysis technique and was supplemented with other sensitivity analyses. Forty-two bacterial genera were associated with COVID-19 susceptibility, hospitalization, and severity in the IVW method. Among these gut microbiota, five gut microbiota (genus unknowngenus [id.1000005472], family unknownfamily [id.1000005471], genus Tyzzerella3, order MollicutesRF9.id.11579, and phylum Actinobacteria) were significantly associated with COVID-19 hospitalization and severity. Three gut microbiota (class Negativicutes, order Selenomonadales, and class Actinobacteria) were significantly associated with COVID-19 hospitalization and susceptibility, while two microbiota (class Negativicutes and order Selenomonadales) were significantly associated with COVID-19 hospitalization and severity, and susceptibility. Sensitivity analysis did not detect any heterogeneity and horizontal pleiotropy. Our findings demonstrated that several microorganisms were causally linked to COVID-19, and improved our understanding of the relationship between gut microbiota and COVID-19 pathology.


Asunto(s)
COVID-19 , Microbioma Gastrointestinal , Microbiota , Humanos , Microbioma Gastrointestinal/genética , Análisis de la Aleatorización Mendeliana , Suplementos Dietéticos , Estudio de Asociación del Genoma Completo , Polimorfismo de Nucleótido Simple
6.
Phys Rev Lett ; 130(21): 210601, 2023 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-37295121

RESUMEN

The task of testing whether two uncharacterized quantum devices behave in the same way is crucial for benchmarking near-term quantum computers and quantum simulators, but has so far remained open for continuous variable quantum systems. In this Letter, we develop a machine learning algorithm for comparing unknown continuous variable states using limited and noisy data. The algorithm works on non-Gaussian quantum states for which similarity testing could not be achieved with previous techniques. Our approach is based on a convolutional neural network that assesses the similarity of quantum states based on a lower-dimensional state representation built from measurement data. The network can be trained off-line with classically simulated data from a fiducial set of states sharing structural similarities with the states to be tested, with experimental data generated by measurements on the fiducial states, or with a combination of simulated and experimental data. We test the performance of the model on noisy cat states and states generated by arbitrary selective number-dependent phase gates. Our network can also be applied to the problem of comparing continuous variable states across different experimental platforms, with different sets of achievable measurements, and to the problem of experimentally testing whether two states are equivalent up to Gaussian unitary transformations.


Asunto(s)
Algoritmos , Redes Neurales de la Computación , Aprendizaje Automático
7.
BMC Oral Health ; 23(1): 918, 2023 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-38001472

RESUMEN

OBJECTIVE: The muscle quality index (MQI) is a measurement of muscle quality that is directly related to overall health. There has been little study on the relationship between the muscle quality index and periodontitis in American people beyond 30 years. Therefore, this study aimed to explore the link between periodontitis and Muscle quality index (MQI) in older Americans. METHODS: Three thousand two hundred fifty-eight individuals (aged 30 to 59) who participated in the National Health and Nutrition Examination Survey (NHANES) 2011-2014 were considered eligible for the cross-sectional investigation. A hand dynamometer was used to determine the handgrip strength (HGS). Dual-energy X-ray absorptiometry was employed to calculate ASM (DXA). MQIArm was calculated by dividing the dominant hand's HGS by the dominant arm's ASM (in kg/kg). MQIApp was calculated by dividing the dominant hand's HGS by the ASM (in kg/kg). MQItotal was calculated by dividing the sum of the dominant and non-dominant hands by the ASM (in kg/kg). To investigate the link between muscle quality index and periodontal disease, the weighted multivariable logistic regression models were used. Using generalized additive models, it was determined if a nonlinear connection existed. Then, we developed a two-piece linear regression model and calculated the inflection point using a recursive approach. A mediation study was performed to determine how much of the impact of MQItotal on periodontitis was mediated by potential variables. RESULTS: Three thousand two hundred fifty-eight participants from the United States were enrolled. The OR (95% CI) for the relationship between MQItotal and periodontitis in the regression model with fully adjusted variables was 0.69 (0.53-0.91), for the connection between MQIArm and periodontitis was 0.90 (0.84-0.97), and for the association between MQIApp and periodontitis was 0.49 (0.30-0.80). MQItotal and periodontitis were shown to have a J-shaped relationship with a change point of 3.64. Before the change point, the OR (95% CI) was 0.69 (0.58, 0.82). In the analysis of drinking and married status, the interaction was statistically significant. Analysis of mediation showed that alcohol use was responsible for 0.4% (0.10 to 1.2) of the effect of MQItotal on periodontitis. CONCLUSION: In American adults aged over 30, the Muscle Quality Index (MQI) exhibited an independent negative correlation with moderate to severe periodontitis, demonstrating a J-shaped relationship. Furthermore, alcohol consumption may act as a mediator in the association between MQI and periodontitis.


Asunto(s)
Enfermedades Periodontales , Periodontitis , Adulto , Humanos , Estados Unidos/epidemiología , Anciano , Estudios Transversales , Encuestas Nutricionales , Análisis de Mediación , Fuerza de la Mano , Enfermedades Periodontales/complicaciones , Periodontitis/complicaciones , Músculos
8.
Angew Chem Int Ed Engl ; 62(18): e202300167, 2023 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-36882908

RESUMEN

Biological proton channels play important roles in the delicate metabolism process, and have led to great interest in mimicking selective proton transport. Herein, we designed a bioinspired proton transport membrane by incorporating flexible 14-crown-4 (14C4) units into rigid frameworks of polyimine films by an interfacial Schiff base reaction. The Young's modulus of the membrane reaches about 8.2 GPa. The 14C4 units could grab water, thereby forming hydrogen bond-water networks and acting as jumping sites to lower the energy barrier of proton transport. The molecular chains present a vertical orientation to the membrane, and the ions travel between the quasi-planar molecular sheets. Furthermore, the 14C4 moieties could bond alkali ions through host-guest interactions. Thus, the ion conductance follows H+ ≫K+ >Na+ >Li+ , and an ultrahigh selectivity of H+ /Li+ (ca. 215) is obtained. This study provides an effective avenue for developing ion-selective membranes by embedding macrocycle motifs with inherent cavities.

9.
Angew Chem Int Ed Engl ; 62(1): e202212120, 2023 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-36329000

RESUMEN

Biological ion channels existing in organisms are critical for many biological processes. Inspired by biological ion channels, the heterogeneous electrospinning nanofiber membranes (HENM) with functional ion channels are constructed by electrospinning technology. The HENM successfully realizes ion-gating effects, which can be used for tunable energy conversions. Introduction of pyridine and carboxylic acid groups into the HENM plays an important role in generating unique and stable ion transport behaviors, in which gates become alternative states of open and close, responding to symmetric/asymmetric pH stimulations. Then we used the HENM to convert osmotic energy into electric energy which reach a maximum value up to 12.34 W m-2 and the output power density of HENM-based system could be regulated by ion-gating effects. The properties of the HENM provide widespread potentials in application of smart nanofluidic devices, energy conversion, and water treatment.


Asunto(s)
Nanofibras , Nanotecnología , Transporte Iónico , Canales Iónicos/química , Concentración de Iones de Hidrógeno
10.
Angew Chem Int Ed Engl ; 62(23): e202302938, 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-37029469

RESUMEN

Nanofluidic reverse electrodialysis provides an attractive way to harvest osmotic energy. However, most attention was paid to monotonous membrane structure optimization to promote selective ion transport, while the role of external fields and relevant mechanisms are rarely explored. Here, we demonstrate a Kevlar-toughened tungsten disulfide (WS2 ) composite membrane with bioinspired serosa-mimetic structures as an efficient osmotic energy generator coupling light. As a result, the output power could be up to 16.43 W m-2 under irradiation, outperforming traditional two-dimensional (2D) membranes. Both the experiment and simulation uncover that the generated photothermal and photoelectronic effects could synergistically promote the confined ion transport process. In addition, this membrane also possesses great anti-fouling properties, endowing its practical application. This work paves new avenues for sustainable power generation by coupling solar energy.

11.
J Am Chem Soc ; 144(25): 11168-11177, 2022 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-35658470

RESUMEN

Coulombic efficiency (CE) and cycle life of metal anodes (lithium, sodium, zinc) are limited by dendritic growth and side reactions in rechargeable metal batteries. Here, we proposed a concept for constructing an anion concentration gradient (ACG)-assisted solid-electrolyte interphase (SEI) for ultrahigh ionic conductivity on metal anodes, in which the SEI layer is fabricated through an in situ chemical reaction of the sulfonic acid polymer and zinc (Zn) metal. Owing to the driving force of the sulfonate concentration gradient and high bulky sulfonate concentration, a promoted Zn2+ ionic conductivity and inhibited anion diffusion in the SEI layer are realized, resulting in a significant suppression of dendrite growth and side reaction. The presence of ACG-SEI on the Zn metal enables stable Zn plating/stripping over 2000 h at a high current density of 20 mA cm-2 and a capacity of 5 mAh cm-2 in Zn/Zn symmetric cells, and moreover an improved cycling stability is also observed in Zn/MnO2 full cells and Zn/AC supercapacitors. The SEI layer containing anion concentration gradients for stable cycling of a metal anode sheds a new light on the fundamental understanding of cation plating/stripping on metal electrodes and technical advances of rechargeable metal batteries with remarkable performance under practical conditions.

12.
Small ; 17(28): e2101099, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34121315

RESUMEN

The asymmetric ion transport in the nanoconfined space, similar to that of natural ion channels, has attracted broad interest in sensor, energy conversion, and other related fields. Among these systems, the surface charge plays an important role in regulating ion transport behaviors. Herein, this surface charge-regulated asymmetric ion transport behavior is systematically explored in the nanoconfined space and the influence on the performance of nanofluidic energy conversion system. The ion transport behaviors in the nanoconfined space are classified into pure diffusion, electrical double layer, and the polarization controlled state. The asymmetric solution environment or surface charge distribution induces asymmetric ion transport behavior which is largely controlled by the low concentration side. The ion-selectivity and the energy conversion performance can be effectively enhanced by improving the local apparent surface charge (more active sites and higher charge strength) or introducing a selective layer with dense surface charge on the low concentration side. These material design concepts for asymmetric ion transport are further supported by both simulation and experiment. The results provide a significant comprehension for ion behaviors in nanoconfined space and the development of high-performance energy storage and conversion systems.

13.
Phys Rev Lett ; 126(24): 240503, 2021 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-34213942

RESUMEN

Continuous-variable quantum information, encoded into infinite-dimensional quantum systems, is a promising platform for the realization of many quantum information protocols, including quantum computation, quantum metrology, quantum cryptography, and quantum communication. To successfully demonstrate these protocols, an essential step is the certification of multimode continuous-variable quantum states and quantum devices. This problem is well studied under the assumption that multiple uses of the same device result in identical and independently distributed (i.i.d.) operations. However, in realistic scenarios, identical and independent state preparation and calls to the quantum devices cannot be generally guaranteed. Important instances include adversarial scenarios and instances of time-dependent and correlated noise. In this Letter, we propose the first set of reliable protocols for verifying multimode continuous-variable entangled states and devices in these non-i.i.d scenarios. Although not fully universal, these protocols are applicable to Gaussian quantum states, non-Gaussian hypergraph states, as well as amplification, attenuation, and purification of noisy coherent states.

14.
J Cell Physiol ; 234(9): 15836-15846, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30740675

RESUMEN

BACKGROUND: Previous studies have shown that alternative splicing (AS) plays a key role in carcinogenesis and prognosis of cancer. However, systematic profiles of AS signatures in head and neck cancer (HNC) have not yet been reported. METHODS: In this study, AS data, RNA-Seq data, and corresponding clinicopathological information of 489 HNC patients were downloaded from The Cancer Genome Atlas. Univariate and multivariate Cox regression analyses were performed to screen for survival-associated AS events. Functional and pathway enrichment analysis was also performed. The prognostic models and splicing networks were constructed using integrated bioinformatics analysis tools. RESULTS: Among the 42,849 alternating splicing events identified in 10,121 genes, 5,165 survival-associated AS events in 2,419 genes were observed in univariate Cox regression analysis. Among the seven types, alternate terminator events were the most powerful prognostic factors. Multivariate Cox analysis was then used to screen for the AS genes with prognostic value. Four candidate genes (TPM1, CLASRP, PRRC1, and DNASE1L1) were found to be independent prognostic factors for HNC patients. A prognostic prediction model was built based on the four genes. The area under the receiver operating characteristic risk score curve for predicting the survival status of HNC patients was 0.704. In addition, splicing interaction network indicated that the splicing factors have significant functions in HNC. CONCLUSION: A comprehensive analysis of AS events in HNC was performed. A powerful prognostic predictor for HNC patients was established based on AS events could.

15.
Macromol Rapid Commun ; 40(17): e1900101, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31364800

RESUMEN

Polyhedral oligomeric silsesquioxane (POSS)-hybrid polymers have been successfully employed as functional inorganic-organic hybrid materials for various applications due to their well-determined structures. The past 6 years has witnessed growing interest in the rational design and synthetic approaches for POSS-hybrid polymers, driven by the adoption of controlled living radial polymerization and click chemistry. This review addresses developments in the precise manipulation of POSS building blocks via atom transfer radical polymerization, reversible addition-fragmentation chain transfer, and click chemistry. Not only are the structures of POSS-hybrid polymers tunable in terms of chemical composition, molecular weight, and polydispersity, but they are also controllable in sequential and hierarchical chain topology. Finally, some representative cutting-edge applications of POSS-hybrid polymers, including biomedical and energy-related materials, fabrication of nanostructures, and functional surface coating materials, are highlighted.


Asunto(s)
Sistemas de Liberación de Medicamentos , Nanoestructuras/química , Compuestos de Organosilicio/química , Polímeros/química , Ingeniería de Tejidos , Polimerizacion
16.
Rapid Commun Mass Spectrom ; 32(2): 105-112, 2018 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-29027292

RESUMEN

RATIONALE: In situ strontium (Sr) isotope analysis of geological samples by laser ablation multiple collector inductively coupled plasma mass spectrometry (LA-MC-ICP-MS) provides useful information about magma mixing, crustal contamination and crystal residence time. Without chemical separation, during Sr isotope analysis with laser ablation, many kinds of interference ions (such as Rb+ and Kr+ ) are on the Sr isotope spectrum. Most previous in situ Sr isotope studies only focused on Sr-enriched minerals (e.g. plagioclase, calcite). Here we established a simple method for in situ Sr isotope analysis of basaltic glass with Rb/Sr ratio less than 0.14 by LA-MC-ICP-MS. METHODS: Seven Faraday cups, on a Neptune Plus MC-ICP-MS instrument, were used to receive the signals on m/z 82, 83, 84, 85, 86, 87 and 88 simultaneously for the Sr isotope analysis of basaltic glass. The isobaric interference of 87 Rb was corrected by the peak stripping method. The instrumental mass fractionation of 87 Sr/86 Sr was corrected to 86 Sr/88 Sr = 0.1194 with an exponential law. Finally, the residual analytical biases of 87 Sr/86 Sr were corrected with a relationship between the deviation of 87 Sr/86 Sr from the reference values and the measured 87 Rb/86 Sr. The validity of the protocol present here was demonstrated by measuring the Sr isotopes of four basaltic glasses, a plagioclase crystal and a piece of modern coral. RESULTS: The measured 87 Sr/86 Sr ratios of all these samples agree within 100 ppm with the reference values. In addition, the Sr isotopes of olivine-hosted melt inclusions from the Emeishan large igneous province (LIP) were measured to show the application of our method to real geological samples. CONCLUSIONS: A simple but accurate approach for in situ Sr isotope measurement by LA-MC-ICP-MS has been established, which should greatly facilitate the wider application of in situ Sr isotope geochemistry, especially to volcanic rock studies.

17.
Org Biomol Chem ; 14(25): 5936-9, 2016 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-27251323

RESUMEN

The KI-catalyzed reaction of acetone with aromatic carboxylic acids is achieved, leading to α-acyloxycarbonyl compounds in good to excellent yields under mild reaction conditions. The present method exhibits good functional-group compatibility. Notably, this reaction system is even suitable for cinnamic acid, 3-phenylpropiolic acid and 4-phenylbutanoic acid. A kinetic isotope effect (KIE) study indicates that C-H cleavage of the acetone is the rate-limiting step in the catalytic cycle.

18.
Int J Syst Evol Microbiol ; 65(Pt 2): 633-638, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25410941

RESUMEN

A Gram-reaction-negative, aerobic, rod-shaped, non-spore-forming, non-motile bacterial strain, designated BUT-6(T), was isolated from activated sludge of a wastewater-treatment facility. The strain grew at 15-35 °C (optimum 30 °C), pH 4.0-10.0 (optimum pH 7.0) and 0-3.0 % (w/v) NaCl (optimum 1.0 %). Phylogenetic analysis based on 16S rRNA sequences showed that strain BUT-6(T) was most closely related to Tahibacter aquaticus PYM5-11(T) (98.6 % similarity). However, the DNA-DNA relatedness between strain BUT-6(T) and T. aquaticus PYM5-11(T) was 47.1 %. The major fatty acids (>10 % of total fatty acids) of strain BUT-6(T) were iso-C15 : 0, iso-C17 : 1ω9c and iso-C17 : 0. The major respiratory quinone was ubiquinone Q-8. The profile of polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylmethylethanolamine, an unidentified aminophospholipid, three unknown aminolipids and unidentified phospholipids. The DNA G+C content of strain BUT-6(T) was 71.7 mol%. On the basis of the data from the polyphasic taxonomic study presented, strain BUT-6(T) is considered to represent a novel species of the genus Tahibacter, for which the name Tahibacter caeni sp. nov. is proposed. The type strain is BUT-6(T) ( = CCTCC AB 2013266(T) = KACC 17139(T)).


Asunto(s)
Filogenia , Aguas del Alcantarillado/microbiología , Xanthomonadaceae/clasificación , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Ácidos Grasos/química , Datos de Secuencia Molecular , Hibridación de Ácido Nucleico , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Ubiquinona/química , Xanthomonadaceae/genética , Xanthomonadaceae/aislamiento & purificación
19.
Int J Syst Evol Microbiol ; 65(10): 3517-3521, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26297219

RESUMEN

A Gram-stain-negative, strictly aerobic, non-spore-forming, motile, rod-shaped bacterium, designated Q-4T, was isolated from a herbicide-contaminated soil sample in Nanyang, Henan province, China. Strain Q-4T grew optimally in the LB medium without NaCl supplement at a pH range of 6.0­7.0 and a temperature of 30 °C. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain Q-4T was most closely related to 'Pedobacter zeaxanthinifaciens' TDMA-5 (97.4 % 16S rRNA gene sequence similarity), followed by Pedobacter xixiisoli S27T (95.8 %). The genomic DNA G+C content of strain Q-4T was 41.8 mol%. MK-7 was the major respiratory quinone. Phosphatidylethanolamine and phosphoaminolipid were the major polar lipids. The major fatty acids were iso-C15 : 0, iso-C17 : 0 3-OH, C16 : 1ω6c and/or C16 : 1ω7c (summed feature 3) and C16 : 1ω7c/C16 : 1ω6c (summed feature 3). Strain Q-4T showed low DNA­DNA relatedness with 'P. zeaxanthinifaciens' TDMA-5 (21.4 ± 0.6 %). Physiological and biochemical characteristics are able to distinguish strain Q-4T from the most closely related species of the genus Pedobacter. On the basis of genotypic and phenotypic data, strain Q-4T is considered to represent a novel species of the genus Pedobacter, for which the name Pedobacter nanyangensis sp. nov. is proposed. The type strain is Q-4T ( = KCTC 42442T = ACCC 19798T).


Asunto(s)
Herbicidas , Pedobacter/clasificación , Filogenia , Microbiología del Suelo , Contaminantes del Suelo , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Ácidos Grasos/química , Datos de Secuencia Molecular , Hibridación de Ácido Nucleico , Pedobacter/genética , Pedobacter/aislamiento & purificación , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/química
20.
J Org Chem ; 80(2): 911-9, 2015 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-25495388

RESUMEN

Silver-catalyzed C(sp(2))-H functionalization/C-O cyclization has been developed. The scalable reaction proceeds at room temperature in an open flask. The present method exhibits good functional-group compatibility because of the mild reaction conditions. Using a AgNO3 catalyst and a (NH4)2S2O8 oxidant in CH2Cl2/H2O solvent, various lactones are obtained in good to excellent yields. A kinetic isotope effect (KIE) study indicates that the reaction may occur via a radical process.


Asunto(s)
Lactonas/química , Nitrato de Plata/química , Plata/química , Catálisis , Ciclización , Cinética , Estructura Molecular , Temperatura
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