Publications by authors named "Jiangwei Li"

63 Publications

The relationship between abnormal Core binding factor-β expression in human cartilage and osteoarthritis.

BMC Musculoskelet Disord 2021 Feb 11;22(1):174. Epub 2021 Feb 11.

Department of Orthopaedics, The Affiliated Hospital of Guizhou Medical University, Guiyang, China.

Background: This study aimed to investigate the effect of abnormal Core binding factor-β expression on proliferation, differentiation and apoptosis of chondrocytes, and elucidate the relationship between Core binding factor-β and osteoarthritis-related markers and degenerative joint disease.

Methods: Cartilage tissues, from healthy subjects and patients with osteoarthritis, were collected for histology and expression of Core binding factor-β, MMP-13, IL-1β, COMP, and YKL-40. Human articular chondrocytes were cultured in vitro, and a viral vector was constructed to regulate cellular Core binding factor-β expression. Cellular proliferation and apoptosis were observed, and osteoarthritis-related inflammatory factor expression and cartilage metabolite synthesis assayed.

Results: Human osteoarthritis lesions had disordered cartilage structure and cellular arrangement, and increased emptying of cartilage lacunae. Normal cell counts were significantly reduced, cartilage extracellular matrix was obviously damaged, and type II collagen expression was significantly decreased. Core binding factor-β was highly expressed in the osteoarthritis cartilage (p < 0.001), and MMP-13, IL-1β, COMP and YKL-40 expression were greater than found in normal cartilage (p < 0.001). Cellular proliferation in the Core binding factor-β high-expression group was reduced and the total apoptosis rate was increased (p < 0.05), while the opposite was found in the Core binding factor-β inhibition group (p < 0.01). Compared with normal chondrocytes, high Core binding factor-β expression (Osteoarthritis and CBFB/pCDH groups) was associated with significantly increased MMP13, IL-1β, COMP and YKL-40 protein expression (p < 0.01), while Core binding factor-β inhibition (CBFB/pLKO.1 group) was associated with significantly decreased COMP, MMP13, IL-1β and YKL-40 expression in osteoarthritis cells (p < 0.001).

Conclusions: Abnormal Core binding factor-β expression might play an upstream regulatory role in mediating abnormal chondrocyte apoptosis and the inflammatory response. On inhibiting Core binding factor-β expression, a delay in cartilage degeneration was expected.

Trial Registration: The study was registered for clinical trials in ChiCTR: ChiCTR1800017066 (Reg. Date-2018/7/10).
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http://dx.doi.org/10.1186/s12891-021-04043-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7879671PMC
February 2021

sp. nov., a bisphenol A-degrading bacterium isolated from seawater.

Int J Syst Evol Microbiol 2021 Feb;71(2)

Water Innovation, Low Carbon and Environmental Sustainability Research Center, National Taiwan University, Taipei 10617, Taiwan, ROC.

A bisphenol A-degrading bacterium, designated as strain H4, was isolated from surface seawater, which was sampled from the Jiulong River estuary in southeast PR China. Strain H4 is Gram-stain-negative, aerobic, short rod-shaped, lacking bacteriochlorophyll a, motile with multifibrillar stalklike fascicle structures and capable of degrading bisphenol A. Growth of strain H4 was observed at 24-45 °C (optimum, 32 °C), at pH 5.5-9 (optimum, pH 7.0) and in 0-7 % NaCl (optimum, 2 %; w/v) . The 16S rRNA gene sequence of strain H4 showed highest similarity to Ery9 (98.7 %), (98.3 %), PQ-2 (98.1 %) and GM-16 (97.6 %), followed by E4A9 (96.7 %) and Ery22 (96.0 %). Phylogenetic analysis revealed that strain H4 fell within a clade comprising the type strains of species and formed a phyletic line with them that was distinct from other members of the family . The sole respiratory quinone was quinone 10 (Q-10). The predominant fatty acids (>5 % of the total fatty acids) of strain H4 were summed feature 8 (C6 and/or C7), summed feature 3 (C6 and/or C7), C6 and C2-OH. The genomic DNA G+C content was 62.8 mol%. In the polar lipid profile, phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, two unidentified phospholipids, two sphingoglycolipids and three unknown lipids were the major compounds. Based on the genotypic and phenotypic data, strain H4 represents a novel species of the genus , for which the name sp. nov. is proposed. The type strain is H4 (=DSM 102182=MCCC1 K02301).
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http://dx.doi.org/10.1099/ijsem.0.004658DOI Listing
February 2021

Enhanced Photocurrent of All-Inorganic Two-Dimensional Perovskite CsPbICl via Pressure-Regulated Excitonic Features.

J Am Chem Soc 2021 Feb 19;143(6):2545-2551. Epub 2021 Jan 19.

Center for High Pressure Science and Technology Advanced Research (HPSTAR), Shanghai 201203, China.

Pressure processing is efficient to regulate the structural and physical properties of two-dimensional (2D) halide perovskites which have been emerging for advanced photovoltaic and light-emitting applications. Increasing numbers of studies have reported pressure-induced and/or enhanced emission properties in the 2D halide perovskites. However, no research has focused on their photoresponse properties under pressure tuning. It is also unclear how structural change affects their excitonic features, which govern the optoelectronic properties of the halide perovskites. Herein, we report significantly enhanced photocurrents in the all-inorganic 2D perovskite CsPbICl, achieving over 3 orders of magnitude increase at the industrially achievable level of 2 GPa in comparison with its initial photocurrent. Lattice compression effectively regulates the excitonic features of CsPbICl, reducing the exciton binding energy considerably from 133 meV at ambient conditions to 78 meV at 2.1 GPa. Impressively, such a reduced exciton binding energy of 2D CsPbICl is comparable to the values of typical 3D perovskites (MAPbBr and MAPbI), facilitating the dissociating of excitons into free carriers and enhancing the photocurrent. Further pressurization leads to a layer-sliding-induced phase transition and an anomalous negative linear compression, which has not been observed so far in other halide perovskites. Our findings reveal the dramatically enhanced photocurrents in the 2D halide perovskite by regulating its excitonic features and, more broadly, provide new insights into materials design toward extraordinary properties.
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http://dx.doi.org/10.1021/jacs.0c11730DOI Listing
February 2021

Investigation of Interface Thermal Resistance between Polymer and Mold Insert in Micro-Injection Molding by Non-Equilibrium Molecular Dynamics.

Polymers (Basel) 2020 Oct 19;12(10). Epub 2020 Oct 19.

Department of Mechanical Engineering, Faculty of Engineering, National University of Singapore, Singapore 117575, Singapore.

Micro-injection molding has attracted a wide range of research interests to fabricate polymer products with nanostructures for its advantages of cheap and fast production. The heat transfer between the polymer and the mold insert is important to the performance of products. In this study, the interface thermal resistance (ITR) between the polypropylene (PP) layer and the nickel (Ni) mold insert layer in micro-injection molding was studied by using the method of non-equilibrium molecular dynamics (NEMD) simulation. The relationships among the ITR, the temperature, the packing pressure, the interface morphology, and the interface interaction were investigated. The simulation results showed that the ITR decreased obviously with the increase of the temperature, the packing pressure and the interface interaction. Both rectangle and triangle interface morphologies could enhance the heat transfer compared with the smooth interface. Moreover, the ITR of triangle interface was higher than that of rectangle interface. Based on the analysis of phonon density of states (DOS) for PP-Ni system, it was found that the mismatch between the phonon DOS of the PP atoms and Ni atoms was the main cause of the interface resistance. The frequency distribution of phonon DOS also affected the interface resistance.
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http://dx.doi.org/10.3390/polym12102409DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7603370PMC
October 2020

Distinct mechanisms underlying the assembly of microeukaryotic generalists and specialists in an anthropogenically impacted river.

Sci Total Environ 2020 Dec 7;748:141434. Epub 2020 Aug 7.

CAS Key Laboratory of Urban pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China. Electronic address:

Microeukaryotic communities are sensitive to environmental changes; and are considered essential for microbial food webs and biogeochemical cycles. Therefore, understanding the community responses of microeukaryotes to environmental changes is of great ecological significance. Very little is known about the assembly mechanisms underlying the microeukaryotic communities, especially for the key ecological groups (e.g., habitat generalists/specialists) in the riverine ecosystems. Here, we employed 18S rDNA amplicon sequencing to study the assembly processes governing the microeukaryotic communities and their habitat generalists and specialists across three hydrological seasons in a subtropical river in China. The results showed that deterministic and stochastic processes jointly shaped the microeukaryotic communities, where the relative importance of stochastic processes decreased in the following order: wet > normal > dry seasons. However, deterministic processes played more important role in shaping the microeukaryotic communities than those of prokaryotes. Meanwhile, stochastic and deterministic processes were responsible for structuring the microeukaryotic habitat generalists and specialists, respectively. Generally, the pure effects of physicochemical factors on the microeukaryotic communities and their key ecological groups were ~ 1.7 folds than those of the micropollutants. However, several micropollutants (e.g., acetaminophen, benzophenone-3, bisphenol A, sulfadiazine, triclocarban and triclosan) were found to have a strong effect on the habitat specialists. Altogether, we suggested that the ecological responses of the riverine microeukaryotes to micropollutants may vary among species due to the intrinsic differences in their environmental plasticity.
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http://dx.doi.org/10.1016/j.scitotenv.2020.141434DOI Listing
December 2020

Development of a quantitative method to evaluate the printability of filaments for fused deposition modeling 3D printing.

Int J Pharm 2020 Oct 12;588:119760. Epub 2020 Aug 12.

Pharmaceutical Development, Biogen, Cambridge, MA, USA. Electronic address:

Lack of a conventional quantitative characterization method for filament printability has been recognized as a critical barrier to fused deposition modeling (FDM) 3D printing application. In this study, a small molecule drug, indomethacin, was utilized as a model compound. Polymers with various solubility were mixed with model drug and extruded into filaments using hot melt extrusion method. Thirty-two filaments with or without indomethacin were evaluated by texture analyzer to study the correlation between mechanical properties and the printability. Three different texture analysis methods were utilized and compared, and a parameter "toughness" calculated by stiffness test was identified to quantitatively describe the printability of filaments in the FDM 3D printer. The toughness threshold value of printable filament was defined as a process window of certain FDM printing. This study provides a quantitative way to evaluate and predict filament printability, and it has great potential to be applied to FDM filament development and quality control in the pharmaceutical industry.
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http://dx.doi.org/10.1016/j.ijpharm.2020.119760DOI Listing
October 2020

A Highly Efficient and Stable Blue-Emitting Cs Cu Cl I with a 1D Chain Structure.

Adv Mater 2020 Sep 6;32(37):e2002945. Epub 2020 Aug 6.

Materials Research Center for Element Strategy, Tokyo Institute of Technology, Mailbox SE-1, 4259 Nagatsuta, Midori-ku, Yokohama, 226-8503, Japan.

In the field of photonics, alkali copper(I) halides attract considerable attention as lead-free emitters. The intrinsic quantum confinement effects originating from low-dimensional electronic structure lead to high photoluminescence quantum yields (PLQYs). Among them, Cs Cu I is the most promising candidate, satisfying both high PLQY and air stability. In this study, a strategy to explore a new material meeting these requirements through the use of the mixed-anions of I and Cl is proposed. The expectation is maintained that the large difference in ionic radii between them likely results in the formation of a novel compound. Consequently, Cs Cu Cl I with a 1D zigzag chain structure is discovered. This material exhibits blue emission (≈462 nm) with a near-unity quantum yield of 95%. An electronic structure calculation reveals that the localized nature of the valence band maximum is crucial in obtaining efficient self-trapped exciton emission. Moreover, the iodine-bridged 1D connectivity significantly enhances the chemical stability of Cs Cu Cl I , compared with the pure chloride phase. The present findings provide a new perspective for developing air-stable alkali copper(I) halides with highly efficient luminescence.
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http://dx.doi.org/10.1002/adma.202002945DOI Listing
September 2020

Homogeneous selection drives antibiotic resistome in two adjacent sub-watersheds, China.

J Hazard Mater 2020 11 23;398:122820. Epub 2020 May 23.

CAS Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China; Graduate Institute of Environmental Engineering, National Taiwan University, Taipei 106, Taiwan. Electronic address:

Rivers are a significant reservoir of antibiotic resistance genes (ARGs), yet the biogeographic pattern of riverine ARGs and its underlying driving forces remain poorly understood. Here, we used metagenomic approach to investigate the spatio-temporal variation of ARGs in two adjacent sub-watersheds viz. North River (NR) and West River (WR), China. The results demonstrated that Bacitracin (22.8 % of the total ARGs), multidrug (20.7 %), sulfonamide (15.2 %) and tetracycline (10.9 %) were the dominant ARG types. SourceTracker analysis indicated that sewage treatment plants as the main source of ARGs, while animal feces mainly contributed in spreading the ARGs in the upstream of NR. Random forest and network analyses confirmed that NR was under the influence of fecal pollution. PCoA analysis demonstrated that the composition of ARGs changed along with the anthropogenic gradients, while the Raup-Crick null model showed that homogenizing selection mediated by class 1 integron intI1 resulted in stable ARG communities at whole watershed scale. Structural equation models revealed that microbial community, grassland and several non-antibiotic micropollutants may also play certain roles in influencing the distribution of ARGs. Overall, the observed deterministic formation of ARGs in riverine systems calls effective management strategies to mitigate the risks of antibiotic resistance on public health.
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http://dx.doi.org/10.1016/j.jhazmat.2020.122820DOI Listing
November 2020

Corrigendum to "Splenic serum from portal hypertensive patients enhances liver stem cell proliferation and self-renewal via the IGF-II/ERK signaling pathway" [Dig. Liver Dis. 52 (2020) 205-213].

Dig Liver Dis 2020 Apr 6;52(4):472. Epub 2020 Mar 6.

National & Local Joint Engineering Research Center of Biodiagnosis and Biotherapy, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China; Shaanxi Provincial Clinical Research Center for Hepatic & Splenic Diseases, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China. Electronic address:

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http://dx.doi.org/10.1016/j.dld.2020.01.001DOI Listing
April 2020

Assessment of DNA Susceptibility to Denaturation as a Marker of Chromatin Structure.

Curr Protoc Cytom 2019 12;91(1):e65

Brander Cancer Research Institute, New York Medical College, Valhalla, New York.

The susceptibility of DNA in situ to denaturation is modulated by its interactions with histone and nonhistone proteins, as well as with other chromatin components related to the maintenance of the 3D nuclear structure. Measurement of DNA proclivity to denature by cytometry provides insight into chromatin structure and thus can be used to recognize cells in different phases of the cell cycle, including mitosis, quiescence (G ), and apoptosis, as well as to identify the effects of drugs that modify chromatin structure. Particularly useful is the method's ability to detect chromatin changes in sperm cells related to DNA fragmentation and infertility. This article presents a flow cytometric procedure for assessing DNA denaturation based on application of the metachromatic property of acridine orange (AO) to differentially stain single- versus double-stranded DNA. This approach circumvents limitations of biochemical methods of examining DNA denaturation, in particular the fact that the latter destroy higher orders of chromatin structure and that, being applied to bulk cell populations, they cannot detect heterogeneity of individual cells. Because the metachromatic properties of AO have also found application in other cytometric procedures, such as differential staining of RNA versus DNA and assessment of lysosomal proton pump including autophagy, to avert confusion between these approaches and the use of this dye in the DNA denaturation assay, these AO applications are briefly outlined in this unit as well. © 2019 by John Wiley & Sons, Inc. Basic Protocol: Differential staining of single- versus double-stranded DNA with acridine orange.
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http://dx.doi.org/10.1002/cpcy.65DOI Listing
December 2019

Ring1 promotes the transformation of hepatic progenitor cells into cancer stem cells through the Wnt/β-catenin signaling pathway.

J Cell Biochem 2019 Nov 7. Epub 2019 Nov 7.

National & Local Joint Engineering Research Center of Biodiagnosis and Biotherapy, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.

The proliferation of hepatic progenitor cells (HPCs) is observed in reactive conditions of the liver and primary liver cancers. Ring1 as a member of polycomb-group proteins which play vital roles in carcinogenesis and stem cell self-renewal was increased in HCC patients and promoted proliferation and survival of cancer cell by degrading p53. However, the mechanisms of Ring1 driving the progression of hepatocarcinogenesis have not been elucidated. In this study, forced expression Ring1 and Ring1 siRNA lentiviral vectors were utilized to stably overexpression and silence Ring1 in HPC cell line (WB-F344), respectively. Our finding indicated that overexpression of Ring1 in HPCs promoted colony formation, cell multiplication, and invasion in vitro, conversely depletion of Ring1 repressed the biological functions of HPCs relative to controls. The expression of β-catenin was upregulated in the HPCs with overexpression of Ring1, and the correlation analysis also showed that β-catenin and Ring1 had a significant correlation in the liver cancer tissues and adjacent tissues. The activation of the Wnt/β-catenin signaling pathway significantly increased the expression of liver cancer stem cells related (LCSCs)-related molecular markers CD90 and EpCAM, which led to the transformation of HPCs into LCSCs. Most importantly, the injection of HPCs with overexpressed Ring1 into the subcutaneous of nude mice leads to the formation of poorly differentiated HCC neoplasm. Our findings elucidate that overexpression of Ring1 the activated Wnt/β-catenin signaling pathway and drove the transformation of HPCs into cancer stem cell-like cells, suggesting Ring1 has extraordinary potential in early diagnosis of HCC.
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http://dx.doi.org/10.1002/jcb.29496DOI Listing
November 2019

Rh-Catalyzed Regioselective Dialkylation of Cage B-H bonds in o-Carboranes: Oxidative Heck Reactions via an Enol Isomerization.

Org Lett 2019 Oct 25;21(19):8018-8021. Epub 2019 Sep 25.

State Key Laboratory of Fluorine & Nitrogen Chemicals , Xi'an Modern Chemistry Research Institute , Xi'an 710065 , China.

In the presence of a carboxylic acid directing group, Rh-catalyzed regioselective directed dialkylation of B(4,5)-H bonds in carboranes and oxidative coupling with allylic alcohols is reported. This strategy constructs a series of 4,5-dialkylated -carboranes in good yields with excellent regioselectivity. A possible catalytic cycle is proposed that involves a tandem sequence of Rh-catalyzed cage B-H activation, alkene insertion, selective β-H elimination, enol isomerization, and decarboxylation.
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http://dx.doi.org/10.1021/acs.orglett.9b03009DOI Listing
October 2019

Splenic serum from portal hypertensive patients enhances liver stem cell proliferation and self-renewal via the IGF-II/ERK signaling pathway.

Dig Liver Dis 2020 02 5;52(2):205-213. Epub 2019 Sep 5.

National & Local Joint Engineering Research Center of Biodiagnosis and Biotherapy, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China; Shaanxi Provincial Clinical Research Center for Hepatic & Splenic Diseases, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China. Electronic address:

Background: Hypersplenism is a serious complication of portal hypertension (PH) and can affect the prognosis of liver disease. Liver stem cells (LSCs) are involved in liver regeneration and hepatocarcinogenesis after liver cirrhosis.

Aim: To explore the effects and mechanism of the spleen on the proliferation and differentiation of LSCs in PH due to liver cirrhosis.

Methods: Fetal liver stem cells (FLSCs) were treated with splenic serum from liver cirrhosis patients with hypersplenism and control serum from healthy volunteers, and the proliferation, self-renewal, and IGF-II/ERK signaling pathway of FLSCs were then evaluated.

Results: We found that splenic serum from PH patients promoted FLSC proliferation, colony formation, and Ki-67 expression in vitro. Splenic serum from PH also enhanced FLSC spheroid formation in vitro. Mechanistically, we determined that insulin-like growth factor (IGF)-II concentration was elevated in splenic serum from PH patients and could promote FLSC proliferation and self-renewal. Furthermore, both IGF-II and splenic serum from PH patients enhanced ERK signaling activation through IGF-I receptor (IGF-I R) in FLSCs. Consistently, blocking IGF-I R or ERK signaling could attenuate the effects of splenic serum from PH patients on FLSCs.

Conclusions: The spleen in PH patients promotes FLSC proliferation and self-renewal through the IGF-II/ERK signaling pathway.
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http://dx.doi.org/10.1016/j.dld.2019.07.014DOI Listing
February 2020

Concurrent detection of lysosome and tissue transglutaminase activation in relation to cell cycle position during apoptosis induced by different anticancer drugs.

Cytometry A 2019 06 13;95(6):683-690. Epub 2018 Nov 13.

Department of Pathology, New York Medical College, Brander Cancer Research Institute, Valhalla, New York.

Described is the new cytometric approach do detect either stimulation or a collapse of lysosomal proton pump (lysosomes rupture) combined with activation of transglutaminase 2 (TG2) during induction of apoptosis. Apoptosis of human lymphoblastoid TK6 cells was induced by combination of 2-deoxyglucose with the isoquinoline alkaloid berberine, by DNA topoisomerase I inhibitor camptothecin, its analog topotecan, topoisomerase II inhibitors etoposide or mitoxantrone, as well as by the cytotoxic anticancer ribonuclease ranpirnase (onconase). Activity of the proton pump of lysosomes was assessed by measuring entrapment and accumulation of the basic fluorochrome acridine orange (AO) resulting in its metachromatic red luminescence (F ) within these organelles. Activation of TG2 was detected in the same cell subpopulation by the evidence of crosslinking of cytoplasmic proteins revealed by the increased intensity of the side light scatter (SSC) as well as following cell lysis by detergent, by its red fluorescence after staining by sulforhodamine 101. Because at low AO concentration nuclear DNA of the lysed cells was stoichiometrically stained green (F ) its quantity provided information on effects of the drug treatments on cell cycle in relation to activation of TG2. The data reveal that activation of lysosomal proton pump was evident in subpopulations of cells treated with 2-deoxyglucose plus berberine, topotecan, etoposide and mitoxantrone but not with ranpirnase. The collapse of lysosomal proton pump possibly reporting rupture of these organelles was observed in definite cell subpopulations after treatment with each of the studied drugs. Because regardless of the inducer of apoptosis TG2 activation invariably was correlated with lysosomes rupture it is likely that it was triggered by calcium ions or protons released from the ruptured lysosomes. This new methodological approach offers the means to investigate mechanisms and factors affecting autophagic lysosomes proton pump activity vis-à-vis TG2 activation that are common in several pathological states. © 2019 International Society for Advancement of Cytometry.
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http://dx.doi.org/10.1002/cyto.a.23652DOI Listing
June 2019

CsPbICl, All-Inorganic Two-Dimensional Ruddlesden-Popper Mixed Halide Perovskite with Optoelectronic Response.

J Am Chem Soc 2018 09 22;140(35):11085-11090. Epub 2018 Aug 22.

Department of Chemistry , Northwestern University , Evanston , Illinois 60208 , United States.

The two-dimensional Ruddlesden-Popper (RP) phases are an important class of halide perovskites with versatile optoelectronic properties. So far, only organic-inorganic hybrid RP phases involving long organic spacers were reported in this class. Here, we report an all-inorganic RP phase lead halide perovskite, CsPbICl (1, I4/ mmm space group; a = 5.6385(8) Å, c = 18.879(4) Å), synthesized by a solid-state method. The compound exhibits a band gap of E ∼ 3.04 eV and photoconductivity. We find an anomalous band gap evolution in CsPbSn ICl solid solutions. Our combined density functional theory and experimental study supports the thermodynamically stable nature of 1 as a unique ordered phase in the CsPbX (X = Cl, Br, I) system. The calculations suggest that 1 is a direct bandgap semiconductor with relatively small effective carrier mass along the in-plane direction, consistent with the experimentally observed in-plane UV-light photoresponse. We also demonstrate that 1 is promising for radiation detection capable of α-particle counting. Moreover, 1 shows markedly ambient and thermal stability.
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http://dx.doi.org/10.1021/jacs.8b06046DOI Listing
September 2018

Spleen Regulates Hematopoietic Stem/Progenitor Cell Functions Through Regulation of EGF in Cirrhotic Hypersplenism.

Dig Dis Sci 2018 07 3;63(7):1860-1867. Epub 2018 May 3.

National and Local Joint Engineering Research Center of Biodiagnosis and Biotherapy, The Second Affiliated Hospital of Xi'an Jiaotong University, No. 157 Xiwu Road, Xi'an, 710004, Shaanxi Province, China.

Background: Hematopoietic abnormality is a common cause of cirrhotic hypersplenism (CH) complications and death; it causes serious adverse effects and is associated with bleeding, anemia, infection in CH patients. However, the underlying mechanism is unclear.

Aims: We aimed to investigate the effects of the spleen on hematopoiesis and hematopoietic stem/progenitor cells (HSPCs) in CH patients.

Methods: Eleven CH patients were enrolled to assess the effects of the spleen on HSPC functions. Hematopoietic changes were examined by flow cytometry analysis. HSPC functions were detected with colony-forming assays and in vitro cell cultures. Enzyme-linked immunosorbent assay (ELISA) was used to test the concentration of epithelial growth factor (EGF).

Results: The number of HSPCs was decreased in CH patients and was rescued after splenectomy. Serum from CH patients dysregulated HSPCs function, and serum from splenectomy patients restored the dysregulated HSPC function in vitro. The concentration of EGF was decreased in CH patients and was restored to normal level after splenectomy. EGF rescued the dysregulated HSPCs function in vitro.

Conclusions: The spleen can regulate the functions of HSPCs in CH patients by regulating EGF signaling. EGF may be a therapeutic target for CH treatment.
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http://dx.doi.org/10.1007/s10620-018-5091-7DOI Listing
July 2018

Strong impact of anthropogenic contamination on the co-occurrence patterns of a riverine microbial community.

Environ Microbiol 2017 Dec 7;19(12):4993-5009. Epub 2017 Dec 7.

CAS Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment Chinese Academy of Sciences, Xiamen 361021, China.

Although the health of rivers is threatened by multiple anthropogenic stressors with increasing frequency, it remains an open question how riverine microbial communities respond to emerging micropollutants. Here, by using 16S rDNA amplicon sequencing of 60 water samples collected during different hydrological seasons, we investigated the spatio-temporal variation and the co-occurrence patterns of microbial communities in the anthropogenically impacted Jiulong River in China. The results indicated that the riverine microbial co-occurrence network had a nonrandom, modular structure, which was mainly shaped by the taxonomic relatedness of co-occurring species. Fecal indicator bacteria may survive for prolonged periods of time in river water, but they formed an independent module which had fewer interactions with typical freshwater bacteria. Multivariate analysis demonstrated that nutrients and micropollutants [i.e., pharmaceuticals and personal care products (PPCPs)] exerted combined effects in shaping α- and β-diversity of riverine microbial communities. Remarkably, we showed that a hitherto unrecognized disruptive effect of PPCPs on the abundance variations of central species and module communities was stronger than the influence of physicochemical factors, suggesting the key role played by micropollutants for the microbial co-occurrence relationships in lotic ecosystems. Overall, our findings provide novel insights into community assembly in aquatic environments experiencing anthropogenic stresses.
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http://dx.doi.org/10.1111/1462-2920.13942DOI Listing
December 2017

Seasonal and spatial variations of prokaryoplankton communities in a salinity-influenced watershed, China.

FEMS Microbiol Ecol 2017 08;93(8)

CAS Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, P. R. China.

Prokaryotes represent the largest biodiversity pool and drive the biogeochemical cycles in fluvial environments. However, the mechanisms underlying the assembly of prokaryotic communities are largely unexplored at taxonomic and functional levels, simultaneously. Here, we investigated the spatio-seasonal distribution of prokaryoplankton communities in a salinity-influenced watershed, China using 16S rRNA gene amplicon sequencing. The OTUs were divided into core and satellite, based on a statistical approach. Our results indicated that the core taxa accounted for 87.4% of all the communities, predominantly including Betaproteobacteria, Actinobacteria and Thaumarchaeota. Whereas 10 of 22 metabolic phenotypes annotated using METAGENassist had significantly higher relative abundances in the core than satellite communities. Temporal variations in the composition of ammonia-oxidizing prokaryotes could be attributed to the seasonal nutrient concentrations. Multivariate statistical analysis indicated that environmental filtering rather than dispersal limitation is the primary mechanism driving the assembly of the whole, core and satellite communities at both taxonomic and functional levels. Network analysis revealed that the mutualistic interactions might also have certain roles in the assembly of the core taxonomic community. However, taxonomic community fluctuations can only partially reflect the functional community variations. Collectively, this study significantly advanced our understanding of the biogeographic pattern of the fluvial prokaryotic communities.
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http://dx.doi.org/10.1093/femsec/fix093DOI Listing
August 2017

Single-cell RNA sequencing reveals an altered gene expression pattern as a result of CRISPR/cas9-mediated deletion of Gene 33/Mig6 and chronic exposure to hexavalent chromium in human lung epithelial cells.

Toxicol Appl Pharmacol 2017 09 5;330:30-39. Epub 2017 Jul 5.

Department of Pathology, School of Medicine, New York Medical College, Valhalla, NY 10595, United States. Electronic address:

Gene 33 (Mig6, ERRFI1) is an adaptor protein with multiple cellular functions. We recently reported that depletion of this protein promotes lung epithelial cell transformation induced by hexavalent chromium [Cr(VI)]. However, the early molecular events that mediate this process are not clear. In the present study, we used single-cell RNA sequencing to compare gene expression profiles between BEAS-2B lung epithelial cells chronically exposed to a sublethal dose of Cr(VI) with or without CRISPR/cas9-mediated deletion of Gene 33. Our data reveal 83 differentially expressed genes. The most notable changes are genes associated with cell adhesion, oxidative stresses, protein ubiquitination, epithelial-mesenchymal transition/metastasis, and WNT signaling. Up-regulation of some neuro-specific genes is also evident, particularly ubiquitin carboxyl-terminal hydrolase L1 (UCHL1), a deubiquitinase and potential biomarker for lung cancer. Gene 33 deletion and/or Cr(VI) exposure did not cause discernable changes in cell morphology. However, Gene 33 deletion led to a modest but significant reduction of cells in the G2/M phase of the cell cycle regardless of Cr(VI) exposure. Gene 33 deletion also significantly reduced cell proliferation. Interestingly, Cr(VI) exposure eliminated the difference in cell proliferation between the two genotypes. Gene 33 deletion also significantly elevated cell migration. Our data indicate that combined Gene 33 deletion and chronic Cr(VI) exposure produces a gene expression pattern and a phenotype resemble those of the transformed lung epithelial cells. Given the known association of UCHL1 with lung cancer, we propose that UCHL1 is an important player in the early stage of lung epithelial cell transformation and tumorigenesis.
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http://dx.doi.org/10.1016/j.taap.2017.07.003DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5562372PMC
September 2017

Mechanism and optimization for plasma electrolytic liquefaction of sawdust.

Bioresour Technol 2017 Oct 24;241:545-551. Epub 2017 May 24.

Department of Physics, College of Physical Science and Technology, Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, Institute of Electromagnetics and Acoustics, Xiamen University, Xiamen 361005, China.

In this work, plasma electrolytic technology was successfully employed to achieve fast liquefaction of sawdust when polyethylene glycol 200 (PEG 200) and glycerol were used as liquefacient in the presence of the catalyst sulfuric acid. Results showed that H ions could heat the solution effectively during the plasma electrolytic liquefaction (PEL) process. The influence of some key parameters including liquefaction time, catalyst percentage, liquefacient/sawdust mass ratio, and PEG 200/glycerol molar ratio on the liquefaction yield were investigated. Based on the results of single factor experiments, response surface methodology (RSM) was applied to optimize the liquefaction process. Under the optimal conditions that is liquefaction time of 5.10min, catalyst percentage of 1.05%, liquefacient/sawdust mass ratio of 7.12/1 and PEG 200/glycerol molar ratio of 1.40/1, the liquefaction yield reached 99.48%. Hence, it could be concluded that PEL has good application potential for biomass fast liquefaction.
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http://dx.doi.org/10.1016/j.biortech.2017.05.132DOI Listing
October 2017

ATM Activation and H2AX Phosphorylation Induced by Genotoxic Agents Assessed by Flow- and Laser Scanning Cytometry.

Methods Mol Biol 2017 ;1599:183-196

Department of Pathology, Brander Cancer Research Institute, New York Medical College, Basic Sciences Building, 15 Dana Road, Valhalla, NY, 10595, USA.

Activation of Ataxia Telangiectasia Mediated protein kinase (ATM) by its phosphorylation on serine 1981 and phosphorylation of histone H2AX on serine 139 (γH2AX) are the key events reporting DNA damage, primarily formation of DNA double strand breaks. These events are detected immunocytochemically in individual cells using phospho-specific Abs. The protocols are presented that describe the methodology of immunofluorescent labeling of cells in conjunction with specific staining of cellular DNA. Flow- and imaging-cytometry, the latter exemplified as laser scanning cytometry, is used to quantify intensity of cellular fluorescence reporting activation of ATM and induction of γH2AX with respect to cellular DNA content, which in turn reports the cell cycle phase. Different protocols are presented for analysis of cells either grown in suspension or attached to surface of culture vessels. Examples of ATM activation and H2AX phosphorylation in response to DNA damage in leukemic HL-60 cells by DNA topoisomerase I inhibitor topotecan, and in lung carcinoma A549 cells by hydrogen peroxide, are presented.
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http://dx.doi.org/10.1007/978-1-4939-6955-5_14DOI Listing
February 2018

A camel anti-lysozyme CDR3 only domain antibody selected from phage display VHH library acts as potent lysozyme inhibitor.

Acta Biochim Biophys Sin (Shanghai) 2017 Jun;49(6):513-519

Xinjiang Key Laboratory of Biological Resources and Genetic Engineering, College of Life Science and Technology, Xinjiang University, Urumqi 830046, China.

Mimetics of antibody-binding sites represent particularly interesting targets, however they are difficult to identify. In most cases, naturally derived CDR3 peptides show a much lower activity and affinity. In this study, we identified a CDR3 domain antibody with framework 3 (FR3) and FR4 in the flank by screening a lysozyme-immunized phage display VHH library. This antibody has a potent enzyme inhibiting activity and high thermal stability. With sequence alignment and site-directed mutagenic analysis, we found that the cysteine residue at amino acid position 88 in FR3 might play a key role in maintaining the stability of the CDR3 antibody. The small-sized CDR3 domain antibody might act as a new scaffold for affinity transfer, hence making a useful contribution to the understanding of antigen-antibody interactions.
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http://dx.doi.org/10.1093/abbs/gmx037DOI Listing
June 2017

Stable α/δ phase junction of formamidinium lead iodide perovskites for enhanced near-infrared emission.

Chem Sci 2017 Jan 15;8(1):800-805. Epub 2016 Sep 15.

Key Lab of Organic Optoelectronics and Molecular Engineering of Ministry of Education , Department of Chemistry , Tsinghua University , Beijing 100084 , PR. China . Email:

Although formamidinium lead iodide (FAPbI) perovskite has shown great promise in the field of perovskite-based optoelectronic devices, it suffers the complications of a structural phase transition from a black perovskite phase (α-FAPbI) to a yellow non-perovskite phase (δ-FAPbI). Generally, it is pivotal to avoid δ-FAPbI since only α-FAPbI is desirable for photoelectric conversion and near-infrared (NIR) emission. However, herein, we firstly exploited the undesirable δ-FAPbI to enable structurally stable, pure FAPbI films with a controllable α/δ phase junction at low annealing temperature (60 °C) through stoichiometrically modified precursors (FAI/PbI = 1.1-1.5). The α/δ phase junction contributes to a striking stabilization of the perovskite phase of FAPbI at low temperature and significantly enhanced NIR emission at 780 nm, which is markedly different from pure α-FAPbI (815 nm). In particular, the optimal α/δ phase junction with FAI/PbI = 1.2 exhibited preferable long-term stability against humidity and high PLQY of 6.9%, nearly 10-fold higher than that of pure α-FAPbI (0.7%). The present study opens a new approach to realize highly stable and efficient emitting perovskite materials by utilizing the phase junctions.
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http://dx.doi.org/10.1039/c6sc03542fDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5301192PMC
January 2017

An Origami Perovskite Photodetector with Spatial Recognition Ability.

ACS Appl Mater Interfaces 2017 Mar 20;9(12):10921-10928. Epub 2017 Mar 20.

Department of Chemistry, Tsinghua University , Beijing, 100084, China.

Flexible photodetectors are attracting substantial attention because of their promising applications in bendable display and smart clothes which cannot be fulfilled by the existing rigid counterparts. In this work, we demonstrate a newly designed photodetector constructed on the common printing paper. Pencil trace was applied as the graphite electrode. With such a simple and convenient method, the as-prepared photodetector exhibited a satisfactory responsivity of 4.4 mA/W, on/off current ratio of 32, coupled with a high response speed of <10 ms. It also demonstrated excellent mechanical flexibility and durability. Most inspiringly, by an ingenious origami, we created the first perovskite photodetector with a 3D configuration. The cubic photodetector array displayed an excellent spatial recognition ability which could not be achieved in all the previously reported 2D photodetectors. Such a fusion of materials science and the art of origami provides a robust strategy for the design of low-cost flexible electronics, especially for the applications in 3D configurations.
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http://dx.doi.org/10.1021/acsami.7b02213DOI Listing
March 2017

Synergistic Effect of Atmospheric-pressure Plasma and TiO Photocatalysis on Inactivation of Escherichia coli Cells in Aqueous Media.

Sci Rep 2016 12 22;6:39552. Epub 2016 Dec 22.

School of Chemistry, Physics and Mechanical Engineering, Queensland University of Technology, Brisbane, Queensland 4000, Australia.

Atmospheric-pressure plasma and TiO photocatalysis have been widely investigated separately for the management and reduction of microorganisms in aqueous solutions. In this paper, the two methods were combined in order to achieve a more profound understanding of their interactions in disinfection of water contaminated by Escherichia coli. Under water discharges carried out by microplasma jet arrays can result in a rapid inactivation of E. coli cells. The inactivation efficiency is largely dependent on the feed gases used, the plasma treatment time, and the discharge power. Compared to atmospheric-pressure N, He and air microplasma arrays, O microplasma had the highest activity against E. coli cells in aqueous solution, and showed >99.9% bacterial inactivation efficiency within 4 min. Addition of TiO photocatalytic film to the plasma discharge reactor significantly enhanced the inactivation efficiency of the O microplasma system, decreasing the time required to achieve 99.9% killing of E. coli cells to 1 min. This may be attributed to the enhancement of ROS generation due to high catalytic activity and stability of the TiO photocatalyst in the combined plasma-TiO systems. Present work demonstrated the synergistic effect of the two agents, which can be correlated in order to maximize treatment efficiency.
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http://dx.doi.org/10.1038/srep39552DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5177875PMC
December 2016

DNA Damage Response Resulting from Replication Stress Induced by Synchronization of Cells by Inhibitors of DNA Replication: Analysis by Flow Cytometry.

Methods Mol Biol 2017 ;1524:107-119

Department of Pathology, Brander Cancer Research Institute, New York Medical College, 40 Sunshine Cottage Road, Valhalla, NY, 10595, USA.

Cell synchronization is often achieved by transient inhibition of DNA replication. When cultured in the presence of such inhibitors as hydroxyurea, aphidicolin or excess of thymidine the cells that become arrested at the entrance to S-phase upon release from the block initiate progression through S then G and M. However, exposure to these inhibitors at concentrations commonly used to synchronize cells leads to activation of ATR and ATM protein kinases as well as phosphorylation of Ser139 of histone H2AX. This observation of DNA damage signaling implies that synchronization of cells by these inhibitors is inducing replication stress. Thus, a caution should be exercised while interpreting data obtained with use of cells synchronized this way since they do not represent unperturbed cell populations in a natural metabolic state. This chapter critically outlines virtues and vices of most cell synchronization methods. It also presents the protocol describing an assessment of phosphorylation of Ser139 on H2AX and activation of ATM in cells treated with aphidicolin, as a demonstrative of one of several DNA replication inhibitors that are being used for cell synchronization. Phosphorylation of Ser139H2AX and Ser1981ATM in individual cells is detected immunocytochemically with phospho-specific Abs and intensity of immunofluorescence is measured by flow cytometry. Concurrent measurement of cellular DNA content followed by multiparameter analysis allows one to correlate the extent of phosphorylation of these proteins in response to aphidicolin with the cell cycle phase.
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http://dx.doi.org/10.1007/978-1-4939-6603-5_7DOI Listing
January 2018

Synergy of 2-deoxy-D-glucose combined with berberine in inducing the lysosome/autophagy and transglutaminase activation-facilitated apoptosis.

Apoptosis 2017 Feb;22(2):229-238

Department of Pathology, Brander Cancer Research Institute, New York Medical College, BSB 438, Valhalla, NY, 10595, USA.

Utilizing a variety of flow cytometric methods evidence was obtained indicating that a combination of the glucose analog 2-deoxy-D-glucose (2-dG) and the plant alkaloid berberine (BRB) produces synergistic effect in the induction of apoptosis in human lymphoblastoid TK6 cells. The synergistic effect is seen at concentrations of the drugs at which each of them alone shows no cytotoxicity at all. The data suggest that the combination of these drugs, which are known in terms of their overall toxicity, side effects and pharmacokinetics may be considered for further studies as chemopreventive and cancer treatment modalities. Of interest are results indicating that rapamycin, which similarly to BRB, suppresses mTOR signaling, when combined with 2-dG shows no synergistic properties. Metformin, on other hand, requires much higher concentration to show the synergy with 2-dG. Also of interest are the findings pertaining to the methodology of the present study. Specifically, dynamic assessment of cellular viability was performed by using the DRAQ7 cell exclusion fluorochrome present in cultures from 0 to 72 h. Concurrent measurement of lysosomal proton pump using acridine orange as the probe shows activation of lysosomes in the cells treated with 2-dG or BRB alone as well as with the drugs combined. Apoptosis was assessed by measuring DNA fragmentation, cell cycle, activation of caspase-3 and tissue transglutaminase (Tgase). A novel cytometric method was developed based on analysis of lysosomal (acidic vesicles) proton pump in live cells followed by cell lysis with detergent and fluorochrome labeling of proteins and DNA to analyze Tgase activation concurrently with cell cycle, in same population of cells. The data show that the cell subpopulation undergoing apoptosis has increased side (right-angle) light scatter likely due to the presence of the crosslinked (solid state) proteins, the consequence Tgase activation.
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http://dx.doi.org/10.1007/s10495-016-1315-5DOI Listing
February 2017

High Performance of Perovskite Solar Cells via Catalytic Treatment in Two-Step Process: The Case of Solvent Engineering.

ACS Appl Mater Interfaces 2016 Nov 25;8(44):30107-30115. Epub 2016 Oct 25.

Key Lab of Organic Optoelectronics & Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University , Beijing 100084, China.

Currently, the potential mechanism of the solvent-assisted crystallization for mixed cations perovskite thin film (FAMAPbI) prepared via two-step solution-process still remains obscure. Here, we clarified the molecular-competing-reacted process of NHCH═NHI (FAI) and CHNHI (MAI) with PbI(DMSO) complex in dimethyl sulfoxide (DMSO) and diethyl ether (DE) catalytic solvent system in the sequential two-step solution-process. The microscopic dynamics was characterized via the characterizations of in situ photoluminescence spectra. In addition, we found that the thermal stability of the perovskite films suffered from the residual solvent with high boiling point, for example, DMSO. The further DE treatment could promote the volatility process of DMSO and accelerate the crystallization process of perovskite films. The highest PCE over 19% with slight hysteresis effect was eventually obtained with a reproducible FAMAPbI solar cell, which displayed a constant power output within 100 s upon light soaking and stable PCE output within 30 d in the thermal stability test.
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http://dx.doi.org/10.1021/acsami.6b09532DOI Listing
November 2016

Electrochemical Characterization of a Novel Exoelectrogenic Bacterium Strain SCS5, Isolated from a Mediator-Less Microbial Fuel Cell and Phylogenetically Related to Aeromonas jandaei.

Microbes Environ 2016 Sep 9;31(3):213-25. Epub 2016 Jul 9.

Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences.

A facultative anaerobic bacterium, designated as strain SCS5, was isolated from the anodic biofilm of a mediator-less microbial fuel cell using acetate as the electron donor and α-FeOOH as the electron acceptor. The isolate was Gram-negative, motile, and shaped as short rods (0.9-1.3 μm in length and 0.4-0.5 μm in width). A phylogenetic analysis of the 16S rRNA, gyrB, and rpoD genes suggested that strain SCS5 belonged to the Aeromonas genus in the Aeromonadaceae family and exhibited the highest 16S rRNA gene sequence similarity (99.45%) with Aeromonas jandaei ATCC 49568. However, phenotypic, cellular fatty acid profile, and DNA G+C content analyses revealed that there were some distinctions between strain SCS5 and the type strain A. jandaei ATCC 49568. The optimum growth temperature, pH, and NaCl (%) for strain SCS5 were 35°C, 7.0, and 0.5% respectively. The DNA G+C content of strain SCS5 was 59.18%. The isolate SCS5 was capable of reducing insoluble iron oxide (α-FeOOH) and transferring electrons to extracellular material (the carbon electrode). The electrochemical activity of strain SCS5 was corroborated by cyclic voltammetry and a Raman spectroscopic analysis. The cyclic voltammogram of strain SCS5 revealed two pairs of oxidation-reduction peaks under anaerobic and aerobic conditions. In contrast, no redox pair was observed for A. jandaei ATCC 49568. Thus, isolated strain SCS5 is a novel exoelectrogenic bacterium phylogenetically related to A. jandaei, but shows distinct electrochemical activity from its close relative A. jandaei ATCC 49568.
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http://dx.doi.org/10.1264/jsme2.ME15185DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5017797PMC
September 2016

Insight into the CH3NH3PbI3/C interface in hole-conductor-free mesoscopic perovskite solar cells.

Nanoscale 2016 Aug 7;8(29):14163-70. Epub 2016 Jul 7.

Department of Chemistry, Tsinghua University, Beijing 100084, P. R. China.

Perovskite solar cells (PSCs) with hole-conductor-free mesoscopic architecture have shown superb stability and great potential in practical application. The printable carbon counter electrodes take full responsibility of extracting holes from the active CH3NH3PbI3 absorbers. However, an in depth study of the CH3NH3PbI3/C interface properties, such as the structural formation process and the effect of interfacial conditions on hole extraction, is still lacking. Herein, we present, for the first time, an insight into the spatial confinement induced CH3NH3PbI3/C interface formation by in situ photoluminescence observations during the crystallization process of CH3NH3PbI3. The derived reaction kinetics allows a quantitative description of the perovskite formation process. In addition, we found that the interfacial contact between carbon and perovskite was dominant for hole extraction efficiency and associated with the photovoltaic parameter of short circuit current density (JSC). Consequently, we conducted a solvent vapor assisted process of PbI2 diffusion to carefully control the CH3NH3PbI3/C interface with less unreacted PbI2 barrier. The improvement of interface conditions thereby contributes to a high hole extraction proved by the charge extraction resistance and PL lifetime change, resulting in the increased JSC valve.
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http://dx.doi.org/10.1039/c6nr03359hDOI Listing
August 2016