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1.
Ann Palliat Med ; 10(1): 495-500, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33545780

RESUMO

BACKGROUND: The purpose of this study is to investigate the optimal surgical options for different kinds of advanced hip tuberculosis, which are still controversial. METHODS: We reviewed seven advanced hip tuberculosis patients received operations from November 2014 to September 2018. All patients received anti-tubercular chemotherapy at least 2 weeks preoperatively and twelve months postoperatively. One active case with sinus tract of seven patients underwent three-stage operations including two debridements/cement spacer implantations and one total hip arthroplasty, while the other six cases received one = stage arthroplasty surgery. All patients are followed up based on Harris score, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR) and X-ray. RESULTS: The mean follow-up time was 41.6 months, while no reactivation was detected. The average Harris score increased from 40.0 preoperatively to 89.4 at the final follow-up. ESR of 3 active hip tubercular cases decreased from 143.7 mm/L at diagnosis time to 6.7 mm/L at the final follow-up. CRP of 3 active hip tubercular cases decreased from 80.01 mg/L (range, 37.34-136.92 mg/L) at diagnosis time to 1.91 mg/L (range, 1.05-2.57 mg/L) at the final follow-up. The ESR and CRP of all patients had returned to normal level at the final follow-up. No prosthesis dislocation, loosening and neurovascular injury was found. CONCLUSIONS: THA is an effective and safe option for hip tuberculosis. The essentials for good outcome include early diagnosis, regular perioperative anti-tubercular chemotherapy, radical debridement of inflamed tissue and necrotic bone, staged-operation if necessary.

2.
Artigo em Inglês | MEDLINE | ID: mdl-33528347

RESUMO

Strain 11-3T was isolated from the surface seawater along the coast of Xiamen Island, China. Cells were Gram-stain-negative, oxidase- and catalase-positive, short and rod-shaped, nonmotile, 0.5-1.0 µm in width and 1.0-2.0 µm in length. Growth of strain 11-3T was at temperature of 15-37°C (optimum 28-35°C), at pH of 5.0-11.0 (optimum 7.0-9.0) and at salinity range of 0-10 (optimum 0.5-1). Phylogenetic analysis based on the 16S rRNA gene sequence indicated that strain 11-3T belonged to the genus Paracoccus and had the highest similarity with Paracoccus caeni MJ17T (98.1 %), followed by Paracoccus xiamenensis 12-3T (97.1 %), Paracoccus zeaxanthinifaciens ATCC 21588T (97.1 %), Paracoccus aestuarii DSM 19484T (97.0 %), Paracoccus liaowanqingii 2251T (97.0 %), Paracoccus fistulariae KCTC 22803T (97.0 %) and other species of the genus Paracoccus (95.2-96.8 %). The DNA-DNA hybridization values between strain 11-3T and the selected strains (P. caeni MJ17T, P. xiamenensis 12-3T, P. zeaxanthinifaciens ATCC 21588T, P. aestuarii DSM 19484T and P. liaowanqingii 2251T) were 19.4, 19.5, 21.6, 19.3 and 19.8 %, respectively. Corresponding, their ANI values were 77.53, 75.61, 75.36, 75.73 and 75.33 %, respectively. The major fatty acid was summed feature 8 (C18:1 ω6c/ω7c). The major respiratory quinone was Q10. The polar lipids included phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylglycerol (PG), diphosphatidylglycerol (DPG), unidentified glycolipid (GL) and unidentified aminolipid (AL). The DNA G+C content of strain 11-3T was 60.1 %. Based on results of the phylogenetic analysis, phenotypic and chemotaxonomic characteristics, strain 11-3T represents a novel species of the genus Paracoccus, for which the name Paracoccus amoyensis sp. nov. is proposed. The type strain is 11-3T (=MCCC 1A16380T=KCTC 72689T).

3.
BMC Musculoskelet Disord ; 22(1): 62, 2021 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-33430863

RESUMO

BACKGROUND: Recent research has suggested that cardiotrophin-like cytokine factor 1 (CLCF1) may be an important regulator of bone homeostasis. Furthermore, a whole gene chip analysis suggested that the expression levels of CLCF1 in the peripheral blood mononuclear cells (PBMCs) were downregulated in postmenopausal women with osteoporosis. This study aimed to assess whether the expression levels of CLCF1 in PBMCs can reflect the severity of bone mass loss and the related fracture risk. METHODS: In all, 360 postmenopausal women, aged 50 to 80 years, were included in the study. A survey to evaluate the participants' health status, measurement of bone mineral density (BMD), routine blood test, and CLCF1 expression level test were performed. RESULTS: Based on the participants' bone health, 27 (7.5%), 165 (45.83%), and 168 (46.67%) participants were divided into the normal, osteopenia, and osteoporosis groups, respectively. CLCF1 protein levels in the normal and osteopenia groups were higher than those in the osteoporosis group. While the CLCF1 mRNA level was positively associated with the BMD of total femur (r = 0.169, p = 0.011) and lumbar spine (r = 0.176, p = 0.001), the protein level was positively associated with the BMD of the lumbar spine (r = 0.261, p < 0.001), femoral neck (r = 0.236, p = 0.001), greater trochanter (r = 0.228, p = 0.001), and Ward's triangle (r = 0.149, p = 0.036). Both the mRNA and protein levels were negatively associated with osteoporosis development (r = - 0.085, p = 0.011 and r = - 0.173, p = 0.014, respectively). The association between CLCF1 protein level and fracture risk was not significant after adjusting for BMD. CONCLUSIONS: To our knowledge, this is the first clinical study to show that CLCF1 expression levels in the PBMCs of postmenopausal women can reflect the amount of bone mass or the severity of bone mass loss.

4.
Int J Syst Evol Microbiol ; 70(10): 5488-5496, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32886593

RESUMO

A novel Gram-stain-negative, non-motile, strictly aerobic, rod-shaped bacterium was isolated from deep-sea hydrothermal sulfide in the northwest Indian Ocean Ridge and designated as strain IOP_32T. Strain IOP_32T could grow at 4-40 °C (optimum, 37 °C), pH 5-9 (optimum, pH 7-8) and salinity of 0-12 % NaCl (w/v; optimum, 2-3 %). The 16S rRNA gene sequence of strain IOP_32T is most similar to Bizionia fulviae EM7T, Bizionia berychis RA3-3-1T, Bizionia paragorgiae KMM 6029T and Oceanihabitans sediminis S9_10T with 95.5-95.3 % similarity. The phylogenomic analysis indicated that strain IOP_32T forms a distinct lineage with Flaviramulus ichthyoenteri Th78T within the family Flavobacteriaceae. The average nucleotide identity, average amino acid identity and percentage of conserved protein values between strain IOP_32T and the type strains of close genera were 72.3-78.5 %, 67.4-76.9 % and 56.3-61.6 %, respectively. The major cellular fatty acid was anteiso-C15 : 0. The respiratory quinone was MK-6. The polar lipids were mainly composed of phosphatidylethanolamine, an unidentified aminophospholipid and five unidentified polar lipids. Strain IOP_32T is significantly different from related genera, which is reflected by the wide adaptability to temperature and salinity levels, the composition of phospholipids and fatty acids, and the results of phylogenetic analyses. The phenotypic properties and phylogenetic data suggest that the lineage represents a novel genus and species within the family Flavobacteriaceae, for which the name Wocania indica gen. sp. nov. is proposed, with the type strain IOP_32T (=MCCC 1A14017 T=KCTC 62660 T). We also propose the reclassification of Flaviramulus ichthyoenteri as Wocania ichthyoenteri comb. nov. (Th78T=DSM 26285T=JCM 18634T=KCTC 32142T).


Assuntos
Flavobacteriaceae/classificação , Fontes Hidrotermais/microbiologia , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Flavobacteriaceae/isolamento & purificação , Oceano Índico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
5.
Int J Syst Evol Microbiol ; 70(9): 4960-4965, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32762800

RESUMO

A Gram-stain-negative, motile, aerobic and heterotrophic bacterium, designated as GYS_M3HT, was isolated from marine coastal sediment sampled at Xiamen Island. Cells were rod-shaped with one polar flagellum and weakly positive for oxidase and catalase. Growth of the strain occurred at pH 6-9 (optimum, pH 7-8), at 15-37 °C (optimum, 28 °C) and with NaCl concentrations of 1.0-6.0 % (optimum, 2.0 %). It had highest 16S rRNA similarity (97.7 %) to Ketobacter alkanivorans GI5T, followed by the members of the genus Alcanivorax (lower than 91.2 %). The results of phylogenetic analysis indicated that it belonged to the genus Ketobacter within the family Alcanivoracaceae. In addition, the average nucleotide identity and digital DNA-DNA hybridization values between strain GYS_M3HT and K. alkanivorans GI5T were 71.4 and 19.7 %, respectively, indicating that strain GYS_M3HT belonged to a novel species. Its genome consisted of 5 318 758 bp, with a genomic DNA G+C content of 50.0 mol%. The respiratory quinone was Q-8 and the dominant fatty acids were identified as iso-C15 : 0 (25.4 %), C16 : 1 ω6c/C16 : 1 ω7c (14.4 %) and iso-C13 : 0 (7.2 %). The main polar lipids were phosphatidylethanolamine and phosphatidylglycerol. Therefore, based on phenotypic, chemotaxonomic and phylogenetic results, strain GYS_M3HT represents a novel species within the genus Ketobacter, for which the name Ketobacter nezhaii sp. nov. is proposed, with the type strain GYS_M3HT (=MCCC 1A13808T=KCTC 72247T).


Assuntos
Alcanivoraceae/classificação , Sedimentos Geológicos/microbiologia , Filogenia , Alcanivoraceae/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Ilhas , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/química
6.
Medicine (Baltimore) ; 99(28): e20906, 2020 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-32664083

RESUMO

Osteoporosis (OP) is a metabolic bone disease that can cause structural changes in bone marrow cavity. Bone marrow is the hematopoietic organ of adults. Accumulating evidence has shown a close connection between bone marrow hematopoietic function and bone formation. Some studies have revealed that OP is associated with hematopoiesis. However, the relationship is not definite.This study aimed to evaluate the association between peripheral blood cell counts (white blood cells [WBC], red blood cells [RBC], platelets [PLT]), hemoglobin [HGB], and bone mineral density [BMD]) in a sample of Chinese postmenopausal women. This is a retrospective study involving 673 postmenopausal women cases. The BMD of lumbar spine and left hip joint were measured by dual-energy X-ray absorptiometry. The levels of blood cell counts and HGB were measured and analyzed.The study results showed the WBC, RBC, PLT, and HGB levels of postmenopausal women in the OP group were all higher than those in the non-osteoporosis group. Spearman linear trend analysis and partial correlation analysis demonstrated that BMD was negatively correlated with WBC, RBC, PLT, and HGB in postmenopausal women.Due to the differences between different countries and races, and there are few studies on the association of BMD with peripheral blood cell counts and HGB in Chinese Postmenopausal Women. Therefore, more large sample studies are needed.


Assuntos
Grupo com Ancestrais do Continente Asiático/etnologia , Contagem de Células Sanguíneas/métodos , Densidade Óssea/fisiologia , Hemoglobinas/análise , Pós-Menopausa/sangue , Absorciometria de Fóton/métodos , Idoso , Contagem de Células Sanguíneas/tendências , Doenças Ósseas Metabólicas/diagnóstico , Doenças Ósseas Metabólicas/epidemiologia , Doenças Ósseas Metabólicas/fisiopatologia , Estudos de Casos e Controles , Feminino , Hematopoese/fisiologia , Articulação do Quadril/diagnóstico por imagem , Articulação do Quadril/fisiopatologia , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/fisiopatologia , Pessoa de Meia-Idade , Osteogênese/fisiologia , Osteoporose/diagnóstico , Osteoporose/epidemiologia , Osteoporose/fisiopatologia , Estudos Retrospectivos
7.
Int J Syst Evol Microbiol ; 70(7): 4186-4192, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32538740

RESUMO

A Gram-stain-negative, facultative anaerobic, red-pigmented, rod-shaped and non-motile strain (RC1_OXG_1FT) was isolated from deep sea water of the Indian Ocean. It was able to grow at pH 5-8 (optimum, pH 7), at 5-37 °C (optimum, 30 °C), and at salinity (% NaCl, w/v) of 0.5-5 % (optimum, 1-2 %). Catalase- and oxidase-positive. It had highest 16S rRNA gene similarity (96.7 %) to 'Sunxiuqinia dokdonensis' DH1T, followed by Sunxiuqinia faeciviva JAM-BA0302T (96.6 %), Sunxiuqinia elliptica CGMCC 1.9156T (96.2 %), Sunxiuqinia rutila HG677T (96.0 %) and species (less than 92.3 %) of other genera. It belongs to the genus Sunxiuqinia within the phylum Bacteroidetes, based on the phylogenetic analysis. The results of digital DNA-DNA hybridization and average nucleotide identity analyses indicated that the strain belonged to a novel species. Its genome size is 5,250, 885 bp, with DNA G+C content of 40.5 mol%. Genome analysis revealed that the strain possessed many genes involved in polysaccharide degradation, especially hemicellulose degradation, indicating that the strain could maintain its normal metabolism by using recalcitrant organic matter in the oligotrophic deep sea environment. Its principal fatty acids were anteiso-C15 : 0 and iso-C15 : 0 and the major polar lipids were phosphatidylethanolamine, two unidentified glycolipids, three unidentified phospholipids and two unidentified polar lipids. The isoprenoid quinone was MK-7. Based on the phenotypic, chemotaxonomic and genotypic data, the strain represents a novel species within the genus Sunxiuqinia, for which the name Sunxiuqinia indica sp. nov. is proposed. The type strain is RC1_OXG_1FT (=MCCC 1A13858T=KCTC 62805T).


Assuntos
Bacteroidetes/classificação , Filogenia , Água do Mar/microbiologia , Técnicas de Tipagem Bacteriana , Bacteroidetes/isolamento & purificação , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Oceano Índico , Hibridização de Ácido Nucleico , Fosfolipídeos/química , Pigmentação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
8.
Int J Syst Evol Microbiol ; 70(7): 4372-4377, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32579095

RESUMO

A Gram-strain-negative, rod-shaped, aerobic bacterium, designated 216_PA32_1T, was isolated from deep-sea sediment of the Pacific Ocean. Cells of strain 216_PA32_1T were non-motile, oxidase-positive and catalase-negative. The strain could grow at temperatures of 10-45 °C (optimum, 32-35 °C), at pH 5.0-10.0 (optimum, 6.0-7.0) and at salinities of 0-10% (optimum, 2-8%). The principal fatty acid (>10 %) was summed feature 8 (C18:1 ω6c/ω7c). The sole respiratory quinone was Q10 (100 %). The polar lipids included phosphatidylethanolamine, phosphatidylcholine, phosphatidylglycerol, phosphatidylmonomethylethanolamine, two unidentified phospholipids and five unidentified aminolipids. The G+C content of the chromosomal DNA was 66.3 mol%. According to the 16S rRNA gene similarity, strain 216_PA32_1T showed the highest sequence similarity to Pseudooceanicola nitratireducens JLT 1210T (97.3 %), followed by Pseudooceanicola nanhaiensis SS011B1-20T (97.1 %). Phylogenetic trees indicated that strain 216_PA32_1T clustered with strain P. nanhaiensis SS011B1-20T. The average nucleotide identity and the DNA-DNA hybridization values between strain 216_PA32_1T and all species of the genus Pseudooceanicola were below 79.5 and 20.6%, respectively. A combination of the phylogenetic, phenotypic, chemotaxonomic and genomic evidence demonstrated that strain 216_PA32_1T represents a novel species of the genus Pseudooceanicola, for which the name Pseudooceanicola pacificus sp. nov. is proposed. The type strain is 216_PA32_1T (=MCCC 1A14128T=KCTC 72688T).


Assuntos
Sedimentos Geológicos/microbiologia , Filogenia , Rhodobacteraceae/classificação , Água do Mar/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Oceano Pacífico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Rhodobacteraceae/isolamento & purificação , Análise de Sequência de DNA
9.
Int J Syst Evol Microbiol ; 70(5): 3483-3490, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32369004

RESUMO

Two Gram-stain-negative, short rod-shaped and non-flagellated strains, designated 17-4AT and L52-1-41, were isolated from the surface seawater of the Indian Ocean and South China Sea, respectively. The 16S rRNA genes of the two strains shared sequence similarity of 99.45 %. Strain 17-4AT shared the highest 16S rRNA gene similarity of 98.02 % with Pusillimonas caeni EBR-8-1T, followed by Pusillimonas noertemannii BN9T (97.47 %), Pusillimonas soli MJ07T (96.93 %), Parapusillimonas granuli Ch07T (96.68 %), Pusillimonas ginsengisoli DCY25T (96.65 %), Eoetvoesia caeni PB3-7BT (96.63 %), Paracandidimonas caeni 24T (96.34 %), Castellaniella defragrans 54PinT (96.28 %) and Pusillimonas harenae B201T (96.05 %). L52-1-41 shared the highest 16S rRNA gene similarity of 97.74 % with Pusillimonas caeni EBR-8-1T, followed by Pusillimonas noertemannii BN9T (97.47 %), Pusillimonas soli MJ07T (96.65 %), Parapusillimonas granuli Ch07T (96.41 %), Pusillimonas ginsengisoli DCY25T (96.37 %), Eoetvoesia caeni PB3-7BT (96.35 %), Pusillimonas harenae B201T (96.28 %), and Paracandidimonas caeni 24T (96.06 %). The results of phylogenetic analyses indicated that 17-4AT and L52-1-41 formed a stable, distinct and highly supported lineage affiliated to the genus Pusillimonas. The results of the digital DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) analyses indicated that they represented a single species. They featured similar genomic DNA G+C contents of 53.2-53.4 mol%. Activities of catalase and oxidase were negative for both strains. The fatty acids patterns of 17-4AT and L52-1-41 were most similar, mostly comprised of C16 : 0, C17 : 0cyclo, C18 : 0, C18 : 1ω9c and summed feature 8 (C18 : 1ω7c and/or C18 : 1 ω6c). The major polar lipids of the two strains were phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and unidentified aminolipids. The respiratory quinone of the two strains was Q-8. Hence, on the basis of the phenotypic, chemotaxonomic and genotypic data presented in this study, we proposed the classification of both strains as representatives of a novel species named Pusillimonas maritima sp. nov., with the type strain 17-4AT (=MCCC 1A12670T=KCTC 62121T=NBRC 113794T), and another strain L52-1-41 (=MCCC 1A05046=KCTC 52313).


Assuntos
Alcaligenaceae/classificação , Filogenia , Água do Mar/química , Alcaligenaceae/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Oceano Índico , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/química
10.
Int J Syst Evol Microbiol ; 70(1): 373-379, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31613738

RESUMO

A novel alphaproteobacterium, strain WS11T, was isolated from a deep-sea sediment sample collected from the New Britain Trench. The full-length 16S rRNA gene of strain WS11T had the highest sequence similarity of 97.6 % to Rhizobium subbaraonis JC85T, followed by Mycoplana ramosa DSM 7292T (96.9 %) and Rhizobium azooxidifex Po 20/26T (96.8 %). Phylogenetic analysis of concatenated 16S rRNA, atpD and recA gene sequences showed that strain WS11T was deeply separated from the species within the family Rhizobiaceae. Phylogenomic analysis based on the whole-genome protein sequences showed that strain WS11T formed an independent monophyletic branch in the family Rhizobiaceae, paralleled with the species in the families Brucellaceae and Phyllobacteriaceae within the order Rhizobiales. Cells were Gram-stain-negative, oxidase- and catalase-positive, and aerobic short rods (1.5-2.4×0.9-1.0 µm). Growth was observed at salinities ranging from 0 to 5% (optimum, 1 %), from pH 6.5 to 9 (optimum, pH 7) and at temperatures between 20 and 30 °C (optimum, 28 °C). Strain WS11T was piezotolerant, growing optimally at 0.1 MPa (range 0.1-70 MPa). The main fatty acid was summed feature 8 (C18 : 1 ω7c/C18  : 1 ω 6c). The sole respiratory quinone was ubiquinone-10 (Q-10). The predominant polar lipids were phosphatidylcholine, two unidentified aminophospholipids and an unidentified phospholipid. The genome size was about 4.36 Mbp and the G+C content was 62.3 mol%. The combined genotypic and phenotypic data show that strain WS11T represents a novel species of a novel genus in the family Rhizobiaceae, for which the name Georhizobium profundi gen. nov., sp. nov. is proposed (type strain WS11T=MCCC 1K03498T=KCTC 62439T).


Assuntos
Alphaproteobacteria/classificação , Sedimentos Geológicos/microbiologia , Filogenia , Água do Mar/microbiologia , Alphaproteobacteria/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Oceano Pacífico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/análogos & derivados , Ubiquinona/química
11.
Sci Total Environ ; 659: 499-506, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31096379

RESUMO

Heterotrophic fungus-like marine protists are recognized to contribute significantly to the coastal carbon cycling largely due to their high biomass and ability to decompose recalcitrant organic matter. Yet, little is known about their dynamics at polluted coastal environments in the context of heterotrophic microbial communities. Here, we present the dynamics of these protists relative to their heterotrophic counterparts in three different environments, namely Pearl River Estuary (ZJK), Shenzhen Bay (SZW) and Daya Bay (DYW) along the coastline of South China Sea. ZJK and SZW were characterized by low salinity and high N levels with large variations, unlike DYW. However, the average abundance of fungus-like protists did not differ significantly (P > 0.05) among these environments, except that it increased in August (422 ±â€¯264 cells/mL, P < 0.01) over March, May and October. Correlation analysis revealed association of their abundance to different environmental factors, namely dissolved organic N in ZJK (rho = -0.87); NH4+ (rho = 0.64) and Chl a (rho = 0.73) in SZW; and salinity (rho = 0.46), DO (rho = 0.57) and total P (rho = 0.48) in DYW, suggesting distinct influence of trophic conditions. Analysis of their abundance relative to other heterotrophic protists (HP) shows that fungus-like protists display selective advantage over HP in the environment (DWY) with low N levels. Further, the similar biomass fraction (ZJK: 5.97 ±â€¯6.23%, SZW: 5.97 ±â€¯5.28%, and DYW: 12.1 ±â€¯11.4%; P > 0.05) of fungus-like protists relative to heterotrophic bacteria, suggest their invariable contribution to carbon cycling. Thus, dynamics of fungus-like protists in relation to their heterotrophic counterparts is largely regulated by the trophic conditions of coastal environments.


Assuntos
Fenômenos Fisiológicos Bacterianos , Biomassa , Fungos/fisiologia , Microbiota , Água do Mar/microbiologia , Monitoramento Ambiental , Citometria de Fluxo , Processos Heterotróficos , Hong Kong , Microscopia de Fluorescência
12.
ChemSusChem ; 11(18): 3292-3298, 2018 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-30035375

RESUMO

The design of highly active, stable, and low-cost oxygen reduction reaction (ORR) electrocatalysts to replace platinum-based materials is crucial to the development of renewable energy technologies. Herein, novel 3D edge-enriched Fe3 C@C nanocrystals with a core-shell structure grown on reduced graphene oxide (rGO) networks (Fe3 C@C/rGO) are reported as highly efficient and stable electrocatalysts for the ORR. The rGO nanosheets act as a host and provide vital support for local growth of edge-enriched Fe3 C@C nanocrystals, leading to a large surface area of 263 m2 g-1 and superstable hybrid structure. The unique structural design of the Fe3 C@C/rGO hybrid enables fast mass transport and a substantial number of exposed active edge sites for electrocatalytic reaction. The Fe3 C@C/rGO hybrid exhibits excellent ORR catalytic activity, with a high positive onset potential close to 1.0 V, a Tafel slope of 65 mV dec-1 , and excellent durability with only about 8 % current density decay at 0.8 V after 20 000 s continuous operation, which is superior to that of commercial Pt/C catalyst in an alkaline electrolyte.

13.
Int J Syst Evol Microbiol ; 67(12): 4930-4935, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29043958

RESUMO

A Gram-stain-negative, non-motile, aerobic and heterotrophic strain, designated 1-19bT, was isolated from surface seawater in the Indian Ocean. The cells were ovoid or coccus (0.8-1.0 µm in diameter) with no flagellum. Activities of catalase and oxidase were positive. Growth was observed at salinity of 0.5-10 (%NaCl, w/v) with an optimum of 3-4, at pH 5-10 with an optimum of 7-8, and at 5-37 °C with an optimum of 28-35 °C. It accumulated poly-ß-hydroxybutyrate granules inside the cell. Bacteriochlorophyll a was absent. The respiratory quinone was Q-10 and the dominant fatty acid was summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c). The major polar lipids comprised phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine, diphosphatidylglycerol, an unidentified phospholipid and two unidentified polar lipids. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain 1-19bT belonged to the family Rhodobacteraceae and formed a distinct monophyletic clade with 'Oceaniovalibus guishaninsula' JLT2003 and Pontibaca methylaminivorans GRP21T, exhibiting similarities of 94.7 and 92.2 %, respectively. The genomic DNA G+C content was 64.2 mol%. Based on the phenotypic, chemotaxonomic and genotypic data, strain 1-19bT represents a novel species in a new genus of the family Rhodobacteraceae, for which the name Oceaniglobus indicus gen. nov., sp. nov. is proposed, with the type strain 1-19bT (=MCCC 1A11863T=KCTC 52709T).


Assuntos
Filogenia , Rhodobacteraceae/classificação , Água do Mar/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Hidroxibutiratos/metabolismo , Oceano Índico , Fosfolipídeos/química , Poliésteres/metabolismo , RNA Ribossômico 16S/genética , Rhodobacteraceae/genética , Rhodobacteraceae/isolamento & purificação , Salinidade , Análise de Sequência de DNA , Ubiquinona/análogos & derivados , Ubiquinona/química
14.
Phys Chem Chem Phys ; 19(7): 4956-4961, 2017 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-28155953

RESUMO

The electron transport layer (ETL) plays a critical role in high efficiency perovskite solar cells. In this study, an anodic TiO2 nanotube film was transformed into a TiO2 nanotube network film, which maintained its advantage as an efficient ETL for perovskite solar cells. Compared with the mesoporous TiO2 nanoparticle ETL, the TiO2 nanotube network ETL can increase the efficiency of perovskite solar cells by 26.6%, which is attributed to its superior charge collection property and light trapping ability. The results confirm the importance of optimizing the electron collecting layer and suggest another way to design and fabricate novel perovskite solid state solar cells, potentially by using a TiO2 nanotube network film as an alternative high efficiency electrode.

15.
Nanoscale ; 8(15): 8228-35, 2016 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-27029963

RESUMO

Although lithium-sulfur (Li-S) batteries have attracted much attention due to their high theoretical specific energy and low cost, their practical applications have been severely hindered by poor cycle life, inadequate sulfur utilization, and the insulating nature of sulfur. Here, we report a rationally designed Li-S cathode with a dual-confined configuration formed by confining sulfur in 2D carbon nanosheets with an abundant porous structure followed by 3D graphene aerogel wrapping. The porous carbon nanosheets act as the sulfur host and suppress the diffusion of polysulfide, while the graphene conductive networks anchor the sulfur-adsorbed carbon nanosheets, providing pathways for rapid electron/ion transport and preventing polysulfide dissolution. As a result, the hybrid electrode exhibits superior electrochemical performance, including a large reversible capacity of 1328 mA h g(-1) in the first cycle, excellent cycling stability (maintaining a reversible capacity of 647 mA h g(-1) at 0.2 C after 300 cycles) with nearly 100% Coulombic efficiency, and a high rate capability of 512 mA h g(-1) at 8 C for 30 cycles, which is among the best reported rate capabilities.

16.
Phys Chem Chem Phys ; 18(6): 4643-51, 2016 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-26794602

RESUMO

Band gap opening and modulating are critical in dictating the functionalities of single walled carbon nanotubes (SWCNTs) in a broad array of nano-devices. Using first-principles density functional theory calculations, a class of semiconducting armchair SWCNTs with a distinctive BN line defect are studied, showing a super capacity to open the band gap of (4, 4) SWCNT to as large as 0.86 eV, while the opened band gap are found decreasing with the increasing diameters of SWCNTs. The opened band gap of SWCNTs can also be successfully modulated through both mechanical and electrical approaches by applying compressive uniaxial strain and electric field. This study provides novel insights into the large band gap opening and modulating of SWCNTs and could be useful in facilitating future applications of SWCNTs in electronic, optical and thermoelectric devices.

17.
ACS Appl Mater Interfaces ; 7(15): 7855-62, 2015 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-25826636

RESUMO

A multilayered structural silicon-reduced graphene oxide electrode with superior electrochemical performance was synthesized from bulk Si particles through inexpensive electroless etching and graphene self-encapsulating approach. The prepared composite electrode presents a stable charge-discharge performance with high rate, showing a reversible capacity of 2787 mAh g(-1) at a charging rate of 100 mA g(-1), and a stable capacity over 1000 mAh g(-1) was retained at 1 A g(-1) after 50 cycles with a high columbic efficiency of 99% during the whole cycling process. This superior performance can be attributed to its novel multilayered structure with porous Si particles encapsulated, which can effectively accommodate the large volume change during the lithiation process and provide increased electrical conductivity. This facile low-cost approach offers a promising route to develop an optimized carbon encapsulated Si electrode for future industrial applications.

18.
Chem Commun (Camb) ; 50(48): 6368-71, 2014 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-24801107

RESUMO

Freestanding TiO2 nanotube array films are fabricated and first applied as electrodes in perovskite CH3NH3PbI3 sensitized solar cells. The device demonstrates improved light absorption with more than 90% of light absorbed in the whole visible range and a reduced charge recombination rate, leading to a significant improvement of the photocurrent and efficiency. This study suggests a promising way of improving the conversion efficiency of perovskite solar cells through novel electrodes.

19.
Environ Sci Technol ; 48(5): 3047-55, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24483341

RESUMO

Although silicon nanowires (SiNW) have been widely studied as an ideal material for developing high-capacity lithium ion batteries (LIBs) for electric vehicles (EVs), little is known about the environmental impacts of such a new EV battery pack during its whole life cycle. This paper reports a life cycle assessment (LCA) of a high-capacity LIB pack using SiNW prepared via metal-assisted chemical etching as anode material. The LCA study is conducted based on the average U.S. driving and electricity supply conditions. Nanowastes and nanoparticle emissions from the SiNW synthesis are also characterized and reported. The LCA results show that over 50% of most characterized impacts are generated from the battery operations, while the battery anode with SiNW material contributes to around 15% of global warming potential and 10% of human toxicity potential. Overall the life cycle impacts of this new battery pack are moderately higher than those of conventional LIBs but could be actually comparable when considering the uncertainties and scale-up potential of the technology. These results are encouraging because they not only provide a solid base for sustainable development of next generation LIBs but also confirm that appropriate nanomanufacturing technologies could be used in sustainable product development.


Assuntos
Fontes de Energia Elétrica , Eletricidade , Meio Ambiente , Lítio/química , Veículos Automotores , Nanofios/química , Silício/química , Eletrodos , Íons/química , Nanofios/ultraestrutura , Óxidos/química , Incerteza
20.
ACS Appl Mater Interfaces ; 6(6): 4154-9, 2014 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-24555988

RESUMO

Sulfur nanoparticles wrapped with a conductive graphene framework was synthesized with a high sulfur loading through a scalable one-step process. The graphene-coated sulfur nanostructured composite, when used as cathode for lithium sulfur battery, shows a reversible capacity of 808 mAh g(-1) at a rate of 210 mA g(-1) and an average columbic efficiency of ∼98.3% over 100 cycles. It is found that graphene oxide (GO) with a porous structure offers flexible confinement function that helps prevent the loss of active materials, thus extending the cycling life of the electrode. Moreover, reduced graphene oxide provides a conductive network surrounding the sulfur particles, which facilitates both electron transport and ion transportation. This novel one-step, all-solution-based process is scalable and provides a promising approach for potential industrial applications.

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