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ABSTRACT In this study, a synthetic microbial consortium containing exoelectrogen Shewanella oneidensis MR-1 and riboflavin-producing strain, Bacillus subtilis RH33, was rationally designed and successfully constructed, enabling a stable, multiple cycles of microbial fuel cells (MFCs) operation for more than 500 h. The maximum power density of MFCs with this synthetic microbial consortium was 277.4 mW/m2, which was 4.9 times of that with MR-1 (56.9 mW/m2) and 40.2 times of RH33 (6.9 mW/m2), separately. At the same time, the Coulombic efficiency of the synthetic microbial consortium (5.6%) was higher than MR-1 (4.1%) and RH33 (2.3%). Regardless the high concentration of riboflavin produced by RH33, the power density of RH33 was rather low. The low bioelectricity generation can be ascribed to the low efficiency of RH33 in utilizing riboflavin for extracellular electron transfer (EET). In the synthetic microbial consortium of MR-1 and RH33, it was found that both mediated and direct electron transfer efficiencies were enhanced. By exchanging the anolyte of MR-1 and RH33, it was confirmed that the improved MFC performance with the synthetic microbial consortium was because MR-1 could efficiently utilize the high concentration of riboflavin produced by RH33. Biotechnol. Bioeng. 2017;114: 526-532. © 2016 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

ABSTRACT Electroactive biofilms play essential roles in determining the power output of microbial fuel cells (MFCs). To engineer the electroacitve biofilm formation of Shewanella oneidensis MR-1, a model exoelectrogen, we herein heterologously overexpressed a c-di-GMP biosynthesis gene ydeH in S. oneidensis MR-1, constructing a mutant strain in which the expression of ydeH is under the control of IPTG-inducible promoter, and a strain in which ydeH is under the control of a constitutive promoter. Such engineered Shewanella strains had significantly enhanced biofilm formation and bioelectricity generation. The MFCs inoculated with these engineered strains accomplished a maximum power density of 167.6 ± 3.6 mW/m2, which was ∼ 2.8 times of that achieved by the wild-type MR-1 (61.0 ± 1.9 mW/m2). In addition, the engineered strains in the bioelectrochemical system at poised potential of 0.2 V vs. saturated calomel electrode (SCE) generated a stable current density of 1100 mA/m2, ∼ 3.4 times of that by wild-type MR-1 (320 mA/m2). Biotechnol. Bioeng. 2015;112: 2051-2059. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Micro-/nano-structured spherical intergrown LiMn2O4–LiNi0.5Mn1.5O4 (LMO–LNMO I, LiNi0.25Mn1.75O4) particles as a cathode material have been synthesized by an impregnation method with highly reactive chestnut-like MnO2 nano-spheres as a manganese source and structural template. The LMO–LNMO I consisted of aggregates of nano-sized particles with a well-defined cubic spinel structure. The electrochemical performance and thermostability of LMO–LNMO I are better than those of a simple mechanical mixture of LiMn2O4 and LiNi0.5Mn1.5O4 (LMO–LNMO M), and much better than those of individual LiMn2O4 and LiNi0.5Mn1.5O4 monomers. Within this special structure, LNMO acts as a skeleton to stabilize the structure of LMO and enables more lithium ions in LMO to participate in the charge–discharge process along with those in LNMO, leading to high specific discharge capacities. In addition, this material exhibits excellent cycle stabilities at room temperature (25 °C) as well as at elevated temperature. It presented a discharge capacity of 130 mA h g−1, with 96.2% capacity retention after 100 cycles at 25 °C at 1 C. When the temperature and rate are increased to 55 °C and 5 C, it still delivers a discharge capacity of 131 mA h g−1, with a capacity retention of 95% after 100 cycles. Being synthesized by a special impregnation method, LMO–LNMO I shows a more homogeneous ion mixing of Ni and Mn in the structure at the atomic level with a more enhanced thermostability due to its high Mn content compared to LNMO. The structural stability and high electrical conductivity of LMO–LNMO I are responsible for the excellent electrochemical performance and outstanding thermal stability. [ABSTRACT FROM AUTHOR]

The microbial fuel cell (MFC), is a promising environmental biotechnology for harvesting electricity energy from organic wastes. However, low bacterial membrane permeability of electron shuttles is a limiting factor that restricts the electron shuttle-mediated extracellular electron transfer (EET) from bacteria to electrodes, thus the electricity power output of MFCs. To this end, we heterologously expressed a porin protein OprF from Pseudomonas aeruginosa PAO1 into Escherichia coli, which dramatically increased its membrane permeability, delivering a much higher current output in MFCs than its parental strain (BL21). We found that the oprF-expression strain showed more efficient EET than its parental strain. More strikingly, the enhanced membrane permeability also rendered the oprF-expression strain an efficient usage of riboflavin as the electron shuttle, whereas its parental strain was incapable of. Our results substantiated that membrane permeability is crucial for the efficient EET, and indicated that the expression of synthetic porins could be an efficient strategy to enhance bioelectricity generation by microorganisms (including electrogenic bacteria) in MFCs. Biotechnol. Bioeng. 2013; 110: 408-416. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

PURPOSE: To detect the status of centrosome and its relationship with the proliferation of ameloblastomas (AB),and investigate the biological effect of centrosome aberration in AB. METHODS: Immunofluorescence and immunohistochemical staining were used to detect the status of centrosome, the nuclear DNA content and the expression of ki-67 in 101 cases of AB, 5 cases of ameloblastic carcinoma, 10 cases of normal oral epithelium and 10 cases of oral squamous cell carcinomas (OSCC). The data were analyzed with SPSS11.0 software package. RESULTS: (1) 29.7% of AB and 70.0% OSCC showed centrosome aberration, while abnormal oral epithelium showed centrosome abnormalities (χ2=165.905, P=0.000).(2) The nuclear DNA content in AB group (15420.37) was significantly higher than that in normal oral epithelium group,but lower than that in OSCC group (F=10.222, P=0.000). (3) Compared with normal oral epithelium, the nuclear DNA content in both AB and OSCC abnormal centrosome groups were significantly different (F=40.901, P=0.000 and F=7.863, P=0.023, respectively), while the two groups had no significant difference (F=10.222, P=0.000). (4) The average of ki-67 was 3.41 and its expression showed an increasing tendency with the recurrence and canceration of AB (F=4.344, P=0.017).(5) Centrome aberration in AB was associated with ki-67 expression (r=0.341, P=0.006) and had no relation with nuclear DNA content (r=0.156, P=0.218). CONCLUSION: Centrosome aberration, associated with the increase of nuclear DNA content, is responsible for the genomic instability observed in parts of ABs. Supported by National Natural Science Foundation of China (Grant No.30672332). [ABSTRACT FROM AUTHOR]

Aim: To report outcomes of endoscopy-assisted vitrectomy (EAV) in patients with chronic hypotony following severe ocular trauma or vitrectomy., Methods: This was a retrospective, noncomparative case series. Ciliary bodies were evaluated using ultrasound biomicroscopy pre-operatively and direct visualisation intraoperatively. All selected individuals (seven patients/seven eyes) underwent EAV. Removal of ciliary membrane and traction, gas/silicone oil tamponade (GT/SOT), and scleral buckling (SB) were performed in selected eyes. Outcome measurements mainly included intraocular pressure (IOP) and best-corrected visual acuity (BCVA)., Results: Seven eyes from 7 male aphakic patients with a mean age of 45 (range, 20-68)y were included in this study; the average follow-up time was 12 (9-15)mo. GT was performed in 2 eyes; membrane peeling (MP) and SOT in 2 eyes; and MP, SOT, and SB in 3 eyes. The mean pre- and post-operative IOP were 4.5 (range, 4.0±0.11 to 4.8±0.2) mm Hg and 9.9 (range, 5.6±0.17 to 12.1±0.2) mm Hg at 52wk (12mo), respectively. BCVA improved in six eyes; one eye still showed light perception, and no bulbi phthisis was observed., Conclusion: Endoscopy offers improved judgment and recognition and has an improved prognosis for chronic hypotony. Therefore, endoscopy can be an effective and promising operative technique for chronic traumatic hypotony management., (International Journal of Ophthalmology Press.)

Singlet oxygen ( 1 O 2 ) is a promising reactive species for the selective degradation of organic pollutants. However, it is difficult to generate 1 O 2 from H 2 O 2 activation with high efficiency and selectivity. In this work, a graphene-supported highly dispersed cobalt catalyst with abundant Co-N x active sites (Co-N-graphene) was synthesized for activating H 2 O 2 . The Co-N-graphene catalyzed H 2 O 2 reaction system selectively catalyzed 1 O 2 production associated with the superoxide radical (O 2 ˙ - ) as the critical intermediate, as proven by scavenger experiments, electron spin resonance (ESR) spin trapping and a kinetic solvent isotope effect study. This resulted in excellent degradation efficiency towards the model organic pollutant methylene blue (MB), with an outstanding pseudo-first-order kinetic rate constant of 0.432 min -1 (g L catalyst -1 ) -1 under optimal reaction conditions ( C H 2 O 2 = 400 mM, initial pH = 9). Furthermore, this Co-N-graphene catalyst enabled strong synergy with HCO 3 - in accelerating MB degradation, whereas the scavenger experiment implied that the synergy herein differed significantly from the current Co 2+ -HCO 3 - reaction system, in which contribution of O 2 ˙ - was only validated with a Co-N-graphene catalyst. Therefore, this work developed a novel catalyst for boosting 1 O 2 production from H 2 O 2 activation and will extend the inventory of catalysts for advanced oxidation processes., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

To explore the medication regularity of Tibetan medicine in the treatment of spleen and stomach diseases, analyze the potential drug targets and interactions of the prescriptions, and reveal the mechanism of Tibetan medicine in the treatment of spleen and stomach diseases. The prescriptions in Tibetan medicine for treatment of spleen and stomach diseases were collected, and Traditional Chinese Medicine Inheritance Support System (TCMISS) was used to analyze the association rules between the herbs and discover the core herbs and new prescriptions. The integrated pharmacology platform V1.0 software was used to construct "herb-compound-target" network and investigate the interactions between various herbs and related pathways of Tibetan medicine Wuwei Shiliu powder in the treatment of spleen and stomach diseases. Among the 216 prescriptions of Tibetan medicine in the treatment of spleen and stomach diseases, pomegranate seed was used at a highest frequency (118 times), followed by white cardamom (107 times) and comatose (107 times). 12 new prescriptions were evolved by using the association rules (support>=34%, confidence>=0.85). 5 242 related drug targets and 20 related pathways were obtained from classic formula Wuwei Shiliu Powder (FDR<0.01). It was proposed that Tibetan medicine treatment for spleen and stomach diseases was mainly based on proliferation of "stomach fire" and the main drugs were for regulating Qi-flowing for strengthening spleen. The mechanism may be associated with regulation of digestive juice secretion, proton pump, mitochondria, regulation of intestinal digestion and immunity, the body's immunity to microorganisms function and other multiple targets and pathways to achieve the joint intervention., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Chinese Pharmaceutical Association.)

Chinese fir plantation is an important part of the subtropical forests in southern China. It has a sustainable natural regeneration ability, which is the foundation of determining community succession direction and maintaining their large area. The main objective of this study was to investigate whether the seed pool was the main restricting factor for the natural regeneration of Chinese fir plantation. Mixed broad leaf-conifer forest and pure plantation of Chinese fir were selected to study the species composition, quantity and seasonal dynamics of all species and dominant species. The results showed that seeds from 21 species belonged to 13 families and 18 genera were collected in the mixed forest, while seeds from 19 species belonged to 12 families and 16 genera were collected from pure forest. Seed rain intensities of all species were 3797 and 3300 seeds·m -2 in mixed forest and pure plantation, respectively. The number of seeds from tree species was absolutely dominant in seed rain (mixed forest 89.1%, pure plantation 86.2%). The number of Chinese fir seeds was the largest, the intact seeds intensities were 825 and 345 seeds·m -2 , respectively. The proportion of all types of seeds in both stands followed the order: the intact seeds > empty or rotten seeds > feeding seeds. The seed rain of both stands had significant seasonal dynamics, both reaching the peak in autumn. The seed rain mainly was intact seeds at the peak of seed-falling. Both mixed forest and pure plantation of Chinese fir had plenty of seeds. The results indicated that the seed rain is not the main factor that restricts natural regeneration in Chinese fir plantations.

Low extracellular electron transfer performance is often a bottleneck in developing high-performance bioelectrochemical systems. Herein, we show that the self-assembly of graphene oxide and Shewanella oneidensis MR-1 formed an electroactive, reduced-graphene-oxide-hybridized, three-dimensional macroporous biofilm, which enabled highly efficient bidirectional electron transfers between Shewanella and electrodes owing to high biomass incorporation and enhanced direct contact-based extracellular electron transfer. This 3D electroactive biofilm delivered a 25-fold increase in the outward current (oxidation current, electron flux from bacteria to electrodes) and 74-fold increase in the inward current (reduction current, electron flux from electrodes to bacteria) over that of the naturally occurring biofilms., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Objective: To investigate the surgical techniques of divided nevus of the eyelids with different locations and sizes., Methods: Retrospective observational case series. Thirty cases (30 eyes) of divided nevus of the eyelids in Zhongshan Ophthalmic Center from July 1997 to November 2006 were retrospectively reviewed. There were three different surgical methods. Excision of the nevus and direct suture after excision in 3 cases. Excision of the nevus and free skin graft transplantation in 5 cases. Excision of the nevus and transfer of skin flap, which included a two stages reconstruction, was performed in 22 cases. The upper or lower eyelid was treated first and another eyelid was treated after three months. Lacrimal punctum and lacrimal canaliculus were excised if they were involved in 8 cases among 22 cases., Results: The mean follow-up time was 60 months (ranging from 2 years to 11 years). Only one case recurred after two years during follow-up and was excised after five years. Pathologic examination indicated malignant transformation. Excision with histopathological control was performed and the nevus did not recur during follow-up time. Recurrence or malignant transformation did not occur in other cases. Aesthetical results of skin flap transplantation were better than skin graft transplantation., Conclusions: The results of two stages reconstruction and transfer of skin flap after excision of the divided nevus are better than free skin graft transplantation. Close observation is required after excision of the divided nevus for early detection of malignant transformation.