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1.
Artigo em Inglês | MEDLINE | ID: mdl-37350580

RESUMO

A Gram-stain-negative, aerobic, flagellated, and long rod-shaped bacterium, designated strain SM1973T, was isolated from an intertidal sediment sample collected from the coast of Qingdao, PR China. Strain SM1973T grew at 15-37 °C and with 0-5.5 % NaCl. It reduced nitrate to nitrite and hydrolysed aesculin but did not hydrolyse casein and gelatin. The strain showed the highest 16S rRNA gene sequence similarity (98.2 %) to the type strain of Spartinivicinus ruber. The phylogenetic trees based on the 16S rRNA genes and single-copy orthologous clusters showed that strain SM1973T clustered with S. ruber, forming a separate lineage within the family Zooshikellaceae. The major cellular fatty acids were summed feature 3 (C16 : 1 ω7с and/or C16 : 1 ω6с) and C16 : 0. The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. The main respiratory quinone was ubiquinone-9. The genomic DNA G+C content of strain SM1973T was 40.4 mol%. Based on the polyphasic evidence presented in this paper, strain SM1973T is considered to represent a novel species within the genus Spartinivicinus, for which the name Spartinivicinus marinus sp. nov. is proposed. The type strain is SM1973T (=MCCC 1K04833T=KCTC 72846T).


Assuntos
Ácidos Graxos , Gammaproteobacteria , Ácidos Graxos/química , Fosfolipídeos , Filogenia , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Composição de Bases , Análise de Sequência de DNA , Técnicas de Tipagem Bacteriana , Gammaproteobacteria/genética
2.
Org Lett ; 25(14): 2405-2409, 2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-37014308

RESUMO

A Rh(I)-catalyzed [5 + 2]/[2 + 2] cycloaddition cascade has been developed to afford a complex and highly strained [4-5-6-7] tetracyclic framework in good yields and excellent diastereoselectivities. During this transformation, three rings, three C-C bonds, and four contiguous stereocenters were formed efficiently. Mechanistically, the rare sterically congested multisubstituted cyclobutanes are constructed readily through Michael addition and a Mannich reaction cascade.

3.
Materials (Basel) ; 17(1)2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38203912

RESUMO

Polymeric dielectrics exhibit remarkable dielectric characteristics and wide applicability, rendering them extensively employed within the domain of electrical insulation. Nevertheless, the electrical strength has always been a bottleneck, preventing its further utilization. Nanocomposite materials can effectively improve insulation strength, but uniform doping of nanofillers in engineering applications is a challenge. Consequently, a nanocomposite interfacial coating was meticulously designed to interpose between the electrode and the polymer, which can significantly improve DC breakdown performance. Subsequently, the effects of filler concentration and coating duration on DC breakdown performance, high field conductivity, and trap distribution characteristics were analyzed. The results indicate that the composite coating introduces deep traps between the electrode-polymer interface, which enhances the carrier confinement, resulting in reduced conductivity and enhanced DC breakdown strength. The incorporation of a composite coating at the interface between the electrode and polymer presents novel avenues for enhancing the dielectric insulation of polymers.

4.
Org Lett ; 24(6): 1394-1399, 2022 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-35132855

RESUMO

An efficient copper-catalyzed asymmetric ring-opening reaction of diaryliodonium salts with imides has been developed, affording a wide range of axially chiral 2-imidobiaryl compounds with excellent enantioselectivities and better convertibility. The potential utility of the current method has been supported by the synthesis of two known chiral ligands with better efficiency, which would be of great significance to the development of other catalytic asymmetric reactions.

5.
Huan Jing Ke Xue ; 42(9): 4341-4349, 2021 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-34414732

RESUMO

Sediment samples were collected from nine sites of three sections, in the intertidal zone of Haizhou bay in July 2018. The abundance and characteristics of microplastics in the sediments (and ragworms within the sediments) were then determined to identify the source of microplastics in ragworms, and to explore the effects of ragworms on microplastics in sediment. The average abundance of microplastics in tidal flat sediments was (0.49±0.17) n·g-1, which was at a high level in domestic offshore environmental studies. Among all the microplastics detected, the most common form and color were fiber and black-gray, respectively, and the materials were mainly polyethylene (PE), polyester (PET), and polystyrene (PS). The detection rate of microplastics in ragworm was 77.78%-86.67%, with an average abundance of (6.68±2.21) n·ind-1; the abundance was significantly correlated with individual mass (r=0.42, P=0.002). The microplastic abundance was significantly higher in ragworms with individual mass over 1.5 g than in those with a mass of<0.5 g or 0.5-1 g (F3=141.029, P=0.000). In ragworms, microplastics were dominated by small black or blue fibers, and the main materials were PE and PET. By analyzing the various characteristics of microplastics with a particle size of 0-3 mm, it was found that the abundance of microplastics in sediments was strongly correlated with that in ragworms (r=0.79,P=0.01); the main form (r=0.90, P=0.035) and the material composition (r=0.73, P=0.024) also showed significant correlation between sediments and ragworms. This indicates that ragworms ingest microplastics in the sedimentary environment and exchange the microplastics with the sediments. Therefore, ragworms can be used as an indicator species of microplastic pollution in sediments.


Assuntos
Microplásticos , Poluentes Químicos da Água , Baías , Monitoramento Ambiental , Sedimentos Geológicos , Plásticos , Poluentes Químicos da Água/análise
6.
Antonie Van Leeuwenhoek ; 114(8): 1293-1305, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34110551

RESUMO

Stingless bees are the main pollinators in tropical and subtropical regions. However, there are only a few studies on the structure and composition of bacteria in the gut and beebread of stingless bees, especially in China. To address this shortage of information, we characterized the microbiota of three common species of stingless bees (Lepidotrigona terminata, Lepidotrigona ventralis and Tetragonula pagdeni) and beebread samples of T. pagdeni. The results showed that the gut of stingless bees contained a set of dominant bacteria, including Acetobacter-like, Snodgrassella, Lactobacillus, Psychrobacter, Pseudomonas, Bifidobacterium and other species. The gut microbiota structures of the three stingless bees were different, and the abundances of bacterial species in the gut varied between communities of the same bee species. The reasons for this are manifold and may include food preference, age and genetic differences. In addition, the abundances of Lactobacillus, Carnimonas, Escherichia-Shigella, Acinetobacter and other species were high in the beebread of stingless bees. In conclusion, our findings reveal the bacteria composition and structure of the gut and beebread of stingless bees in China and deepen our understanding of the dominant bacteria of the gut and beebread of stingless bees.


Assuntos
Microbioma Gastrointestinal , Microbiota , Própole , Animais , Bactérias/genética , Abelhas , China
7.
Zhen Ci Yan Jiu ; 44(9): 677-85, 2019.
Artigo em Chinês | MEDLINE | ID: mdl-31532139

RESUMO

OBJECTIVE: To assess the therapeutic effect and safety of fire needle therapy in the treatment of herpes zoster pain. METHODS: We collected randomized controlled trials about treatment of herpes zoster pain mainly by fire needle therapy (published from the date of establishment of each database to Dec 1 of 2018) from databases of CNKI, Wanfang, VIP, Chinese Biomedical Document Service System (SinoMed), PubMed, Embase, Cochrane Library by using key words of "fire needle" "burnt needle" "red-hot needle" "herpes zoster" "postherpetic neuralgia" and "herpetic neuralgia". Then, we conducted Meta-analysis and sequential analysis about the outcomes of studies met our inclusion criteria using RevMan5.3.5 and TSA0.9.10 Beta softwares and employed GRADE profiler 3.6.1 to grade the quality of evidence. RESULTS: A total of 25 studies including 2 024 patients were brought into the present analysis. Outcomes of the qualitative analysis indicated that the fire needle therapy has a higher effective rate than the western medicine group. Meta-analysis showed that after the treatment mainly with fire needle therapy, 1) the VAS score is evidently lower [WMD=-0.96, 95% CI(-1.22, -0.71), P<0.000 01], 2) the duration of 30% pain relief is obviously shorter [WMD=-1.82, 95% CI (-2.46, -1.18), P<0.000 01], 3) the duration of pain is evidently shorter {fire needle combined with electroacupuncture [WMD=-11.53, 95% CI(-14.57, -8.48), P<0.000 01]; fire needle combined with cupping [WMD=-4.75, 95% CI (-7.99, -1.51), P=0.004]; pure fire needle therapy [WMD=-1.82, 95% CI (-2.46, -1.18), P<0.000 01], and 4) the occurrence rate of post-herpetic neuralgia is considerably lower [RR=0.16, 95% CI (0.09, 0.30), P<0.000 01]. The occurrence and management of adverse events were not mentioned in all the included studies, suggesting no safety problem of the therapy, but the publication bias has not been taken seriously. CONCLUSION: In the treatment of herpes zoster pain, fire needle as the main treatment approach can significantly relieve pain, shorten the pain duration, and reduce the incidence of post-herpetic neuralgia.


Assuntos
Terapia por Acupuntura , Herpes Zoster , Humanos , Neuralgia , Neuralgia Pós-Herpética , Manejo da Dor
8.
Chemistry ; 21(40): 14171-8, 2015 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-26291651

RESUMO

The two-dimensional (2D) metal-organic framework (MOF) [Cd(TPTZ)(H2O)2(HCOOH)(IPA)2]n (1; TPTZ = {4-[4-(1H-1,2,4-triazol-1-yl)phenyl]phenyl}-1H-1,2,4-triazole, IPA = isophthalic acid) has been constructed with the π-electron-rich aromatic ligand TPTZ, auxiliary ligand IPA, and the metal Cd(2+) ion with a d(10) configuration under solvothermal conditions. Complex 1 exhibits a strong ligand-originated photoluminescence emission, which is selectively sensitive toward electron-deficient nitroaromatic compounds, such as nitrobenzene (NB), 1,3-dinitrobenzene (m-DNB), and 1,4-dinitrobenzene (p-DNB), and nitro-aliphatic compounds, such as nitromethane (NM) and tris(hydroxymethyl)nitromethane. This property makes complex 1 a potential fluorescence sensor for these chemicals. Single-crystal X-ray diffraction studies revealed that dinuclear cadmium building units were further bridged by TPTZ ligands to give a four-connected uninodal net with the Schläfli symbol of [4.6(3).4.6(3).6(2).6(4)].

9.
Comput Math Methods Med ; 2014: 857398, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25506389

RESUMO

Variable selection is an important issue in regression and a number of variable selection methods have been proposed involving nonconvex penalty functions. In this paper, we investigate a novel harmonic regularization method, which can approximate nonconvex Lq (1/2 < q < 1) regularizations, to select key risk factors in the Cox's proportional hazards model using microarray gene expression data. The harmonic regularization method can be efficiently solved using our proposed direct path seeking approach, which can produce solutions that closely approximate those for the convex loss function and the nonconvex regularization. Simulation results based on the artificial datasets and four real microarray gene expression datasets, such as real diffuse large B-cell lymphoma (DCBCL), the lung cancer, and the AML datasets, show that the harmonic regularization method can be more accurate for variable selection than existing Lasso series methods.


Assuntos
Análise de Sequência com Séries de Oligonucleotídeos/métodos , Modelos de Riscos Proporcionais , Análise de Sobrevida , Algoritmos , Simulação por Computador , Diagnóstico por Imagem/métodos , Perfilação da Expressão Gênica , Humanos , Leucemia Mieloide Aguda/mortalidade , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Linfoma Difuso de Grandes Células B/mortalidade , Reprodutibilidade dos Testes , Fatores de Risco
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