Advanced BIFs with Co, B, N, and S for Electrocatalytic Oxygen Reduction and Oxygen Evolution Reactions.

In this work, a new alkaline-stable boron imidazolate framework (BIF-90) was rationally designed and successfully synthesized by solvothermal reaction. Due to its potential electrocatalytic active sites (Co, B, N, and S) and chemical stabilities, BIF-90 was explored as a bifunctional electrocatalyst toward electrochemical oxygen reactions, namely, oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). This work will open new avenues toward the design of stable, cheap, and more active BIFs as bifunctional catalysts.

Active Sites In Situ Implanted Hybrid Zeolitic Imidazolate Frameworks for a Water Oxidation Catalyst.

Metal-organic frameworks (MOFs) have been a focus of research because of their unique porous structure, but they are usually not directly for electrocatalysis. Herein, we prepared a special class of Fe/Zn/Mo-based trimetallic hybrid zeolitic imidazolate frameworks by in situ solvothermal synthesis that have the potential to act directly as highly efficient oxygen evolution reaction electrocatalysts. This work provides a foundation for the preparation of multimetal MOFs and expands the investigation of electrocatalysts.

Co-Heteroatom-Based MOFs for Bifunctional Electrocatalysts for Oxygen and Hydrogen Evolution Reactions.

Herein, a Co(II) heteroatom metal-organic framework was successfully post-modified via unsaturated coordinated S precisely capturing Ni2+ on the surface of the porous structure. The newly pristine bimetallic MOFs have increasing active edge sites (Ni(II) and S), boosting electrocatalytic activity toward oxygen evolution reaction and hydrogen evolution reaction.

Highway Freight Transportation Diversity of Cities Based on Radiation Models.

Using a unique data set containing about 15.06 million truck transportation records in five months, we investigate the highway freight transportation diversity of 338 Chinese cities based on the truck transportation probability pij from one city to another. The transportation probabilities are calculated from the radiation model based on the geographic distance and its cost-based version based on the driving distance as the proxy of cost. For each model, we consider both the population and the gross domestic product (GDP), and find quantitatively very similar results. We find that the transportation probabilities have nice power-law tails with the tail exponents close to 0.5 for all the models. The two transportation probabilities in each model fall around the diagonal pij=pji but are often not the same. In addition, the corresponding transportation probabilities calculated from the raw radiation model and the cost-based radiation model also fluctuate around the diagonal pijgeo=pijcost. We calculate four sets of highway truck transportation diversity according to the four sets of transportation probabilities that are found to be close to each other for each city pair. It is found that the population, the gross domestic product, the in-flux, and the out-flux scale as power laws with respect to the transportation diversity in the raw and cost-based radiation models. It implies that a more developed city usually has higher diversity in highway truck transportation, which reflects the fact that a more developed city usually has a more diverse economic structure.

Well-Aligned Ni-Heteroatom (N, S) MOF Arrays Enhanced Electrocatalytic Oxygen Evolution Reaction.

A two-dimensional Ni-heteroatom-based metal-organic framework (MOF) array was directly grown on C paper (Ni-MOF-A/CP) via one-pot solvothermal reaction. According to the strategy for MOF self-assembly on C paper, Ni-MOFs were also synthesized on Ni foam (Ni-MOF/NF) with different sizes and morphologies. The newly resulting MOFs with ternary (Ni, S, and N) active sites exhibited enhanced activity toward oxygen evolution reaction [e.g., Ni-MOF-A/CP: E(5 mA cm-2) = 333 mV and a low Tafel slope of 80 mV dec-1].

Selective Synthesis of Single-Handed Helical Polymers from Achiral Monomer and a Mechanism Study on Helix-Sense-Selective Polymerization.

Inspired by the exquisite helices in Nature, fabrication of helical materials with controlled handedness has attracted considerable attention. Herein, we report on precis synthesis of single left- and right-handed helical polyisocyanides through living polymerization of achiral monomers using chiral palladium catalysts under helix-sense-selective manner. Mechanism study revealed that the yielded helices with opposite handedness showed different activity of the living chain end. The helix with unfavored handedness was self-terminated, while the one with favored handedness showed high activity and could undergo chain propagation to form a high molecular weight polymer with maintained single-handed helicity.

Precise Synthesis of π-Conjugated Block Copolymers and Polymerization-Induced Chiral Self-Assembly toward Helical Nanofibers with Circularly Polarized Luminescence.

Precise synthesis and efficient self-assembly of semiconducting polymers are of great interest. Herein, we report the controlled synthesis of π-conjugated poly(phenyl isocyanide)-b-poly(phenyleneethylene) (PPI-b-PPE) copolymers via chain extension of ethynyl 4-iodobenzene initiated by Pd(II)-terminated helical poly(phenyl isocyanide) (PPI). The in-situ-generated block copolymers self-assembled into various supramolecular architectures depending on the PPE length. The helical PPI segment induced the block copolymers with an appropriate PPE length self-assemble into helical nanofibers with a controlled size and defined helicity. Interestingly, the chiral assemblies of the block copolymers exhibit intense optical activity and emit clear circularly polarized luminescence.

Identification of differentially expressed genes in gills of tiger puffer (Takifugu rubripes) in response to low-salinity stress.

Salinity is an important abiotic factor for aquatic organisms. In fish, changes in salinity affect physiological responses and alter the immune system. Takifugu rubripes is an important economic marine fish, and mechanisms of T. rubripes adaptation to salinity changes need to be further documented. In this study, a transcriptome sequencing technique was used to analyse genes that were differentially expressed in the T. rubripes gill after low-salinity stress for 30 d, and differential gene expression was further validated by quantitative real-time PCR (qPCR). After assembly, 385 differentially expressed genes (DEGs) were identified, including 182 upregulated genes and 203 downregulated genes. The DEGs were assigned to Gene Ontology (GO) classes with a total of 1647 functional terms. Most DEGs were assigned to biological process (984; 59.8%) followed by molecular function (445; 27.0%) and cellular component (218; 13.2%). Further KEGG analysis allocated 385 DEGs to 95 KEGG pathways. After q-value correction, 7 pathways (Glycolysis/Gluconeogenesis; Biosynthesis of amino acids; Carbon metabolism; Fructose and mannose metabolism; Pentose phosphate pathway; Metabolism of xenobiotics by cytochrome P450; and Glycine, serine and threonine metabolism) remained significant. qPCR results indicated that the transcripts of six selected genes sharply increased after 30 d of low-salinity stress. Low-salinity stress obviously increased SLC39A6, SLC5A9, NKAα1, CYP1A1, CYP1B1, and GSTA expression. In contrast, the genes encoding Aldoaa, GPI, FBP2 and GAPDH exhibited downregulation. In addition, three solute carrier (SLC) genes selected from the DEGs were further studied for differential expression patterns after low-salinity exposure, and the results showed that the SLCs were upregulated in T. rubripes after 72 h of low-salinity exposure. This investigation provides data for understanding the molecular mechanisms of fish responses to low-salinity stress and provides a reference for rationally setting salinity levels in aquaculture.

Multifractal analysis of financial markets: a review.

Multifractality is ubiquitously observed in complex natural and socioeconomic systems. Multifractal analysis provides powerful tools to understand the complex nonlinear nature of time series in diverse fields. Inspired by its striking analogy with hydrodynamic turbulence, from which the idea of multifractality originated, multifractal analysis of financial markets has bloomed, forming one of the main directions of econophysics. We review the multifractal analysis methods and multifractal models adopted in or invented for financial time series and their subtle properties, which are applicable to time series in other disciplines. We survey the cumulating evidence for the presence of multifractality in financial time series in different markets and at different time periods and discuss the sources of multifractality. The usefulness of multifractal analysis in quantifying market inefficiency, in supporting risk management and in developing other applications is presented. We finally discuss open problems and further directions of multifractal analysis.

Ultrathin Ni(ii)-based coordination polymer nanosheets as a co-catalyst for promoting photocatalytic H2-production.

Ni(ii) coordination polymer nanosheets (Ni-CPNS) were prepared via a top-down liquid ultrasonication exfoliation method. For the first time, Ni-CPNS was used as a co-catalyst (Ni-CPNS@CdS) via a mechanical grinding strategy. The optimized Ni-CPNS@CdS catalyst reached a super high visible-light photocatalytic hydrogen production activity of 10 210 µmol h-1 g-1, exceeding that of bare CdS nanoparticles by 1480%. Our work can open new avenues towards the design of stable and cheap CPNS co-catalysts to replace expensive and rare noble metals for photocatalysis processes.

Polymorphisms in the APOBEC3G gene of Chinese rhesus macaques affect resistance to ubiquitination and degradation mediated by HIV-2 Vif.

Animal cells have multiple innate effector mechanisms that inhibit viral replication. For the pathogenic retrovirus human immunodeficiency virus 1 (HIV-1), there are widely expressed restriction factors, such as APOBEC3 proteins, tetherin/BST2, SAMHD1 and MX2, as well as TRIM5α. We previously found that the TRIM5α gene clearly affects SIVmac or HIV-2 replication, but the major determinant of the combinatorial effect caused by multiple host restriction factors is still not fully clear. APOBEC3G (apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like 3G), a host restriction factor that restricts HIV replication by causing cytosine deamination, can be targeted and degraded by the SIV/HIV-1/HIV-2 accessory protein Vif. Although rhesus macaques are widely used in HIV/AIDS research, little is known regarding the impact of APOBEC3G gene polymorphisms on viral Vif-mediated ubiquitin degradation in Chinese-origin rhesus macaques. In this study, we therefore genotyped APOBEC3G in 35 Chinese rhesus macaques. We identified a novel transcript and 27 APOBEC3G polymorphisms, including 20 non-synonymous variants and 7 synonymous mutation sites, of which 10 were novel. According to the predicted structure of the A3G protein, we predicted that the E88K and G212D mutations, both on the surface of the A3G protein, would have a significant effect on Vif-induced A3G degradation. However, an in vitro overexpression assay showed that these mutations did not influence HIV-2-Vif-mediated degradation of APOBEC3G. Unexpectedly, another polymorphism L71R, conferred resistance to Vif-mediated ubiquitin degradation, strongly suggesting that L71R might play an important role in antiviral defense mechanisms.

Ni(ii)-doped anionic metal-organic framework nanowire arrays for enhancing the oxygen evolution reaction.

Herein, an anionic metal-organic framework nanowire array not only directly grew on Cu foam, but also captured Ni(ii) ions at an ultra-small particle level. The hybrid material exhibited high activity with low overpotential (310 mV at 20 mA cm-2 in 1.0 M KOH solution) toward the oxygen evolution reaction (OER) (1 M KOH), with performance comparable to that of the precious metal benchmark. These findings may expand the field of MOFs for scaled-up water electrolysis.

Suppression of Tescalcin inhibits growth and metastasis in renal cell carcinoma via downregulating NHE1 and NF-kB signaling.

BACKGROUND: Renal cell carcinoma (RCC) is the most common form of kidney cancer. Recent studies reported that Tescalcin was overexpressed in various tumor types. However, the status of Tescalcin protein expression in RCC and its biological function is uncertain. This study was designed to investigate the expression of Tescalcin in human RCC and its biological function. METHODS: shRNA transfection was performed to abrogates the expression of Tescalcin. Quantitative real time PCR and western blotting assays were used to determine mRNA and protein expression levels, respectively. The cell viability was analyzed by MTT and colony formation. Cell flow cytometry was used to assess pHi value and cell apoptosis. Cell invasive and migratory ability was measured with modified Boyden chamber assay. Xenograft model was setup to evaluate tumor growth. RESULTS: Tescalcin was overexpressed in RCC tissues compared with matched normal tissues. It was also overexpressed in RCC cell lines relative that of normal cells. Suppression Tescalcin with specific shRNA resulted in the inhibition of cell proliferation, migration, invasion and apoptosis of RCC cells. Additionally, silencing of Tescalcin also caused the inhibition of the tumor growth in nude mice. Mechanistic study showed that Tescalcin regulated cell proliferation, migration and invasion via NHE1/pHi axis as well as AKT/NF-κB signaling pathway. CONCLUSIONS: These findings demonstrate that atopic expression of Tescalcin facilitates the survival, migration and invasion of RCC cells via NHE1/pHi axis as well as AKT/ NF-κB signaling pathway, providing new perspectives for the future study of Tescalcin as a therapeutic target for RCC.

Forecasting extreme atmospheric events with a recurrence-interval-analysis-based autoregressive conditional duration model.

With most city dwellers in China subjected to air pollution, forecasting extreme air pollution spells is of paramount significance in both scheduling outdoor activities and ameliorating air pollution. In this paper, we integrate the autoregressive conditional duration model (ACD) with the recurrence interval analysis (RIA) and also extend the ACD model to a spatially autoregressive conditional duration (SACD) model by adding a spatially reviewed term to quantitatively explain and predict extreme air pollution recurrence intervals. Using the hourly data of six pollutants and the air quality index (AQI) during 2013-2016 collected from 12 national air quality monitoring stations in Beijing as our test samples, we attest that the spatially reviewed recurrence intervals have some general explanatory power over the recurrence intervals in the neighbouring air quality monitoring stations. We also conduct a one-step forecast using the RIA-ACD(1,1) and RIA-SACD(1,1,1) models and find that 90% of the predicted recurrence intervals are smaller than 72 hours, which justifies the predictive power of the proposed models. When applied to more time lags and neighbouring stations, the models are found to yield results that are consistent with reality, which evinces the feasibility of predicting extreme air pollution events through a recurrence-interval-analysis-based autoregressive conditional duration model. Moreover, the addition of a spatial term has proved effective in enhancing the predictive power.

Transcriptome from Pacific cod liver reveals types of apolipoproteins and expression analysis of AFP-IV, structural analogue with mammalian ApoA-I.

Apolipoproteins (Apos), transporting the lipids through the lymphatic and circulatory systems, are associated with kinds of diseases. Additionally, type IV antifreeze protein (AFP-IV) was related evolutionarily with apolipoproteins. However, the information of Apos in fish was limited. In this study, ApoA-I, ApoA-I-2, ApoA-IV, Apo E, ApoB-100-like and AFP-IV were sequenced from Pacific cod (Gadus macrocephalus) liver transcriptome using Illumina HiSeq 2000, and their 3-D models were constructed based on the most confidence templates ever reported in mammals. Interestingly, the model of G. macrocephalus AFP-IV, named GmAFPIV, is quite similar to the structure of ApoA-I. GmAFPIV includes 689 bases with a complete open reading frame encoding 125 amino acids. Sequence alignment of GmAFPIV showed 30% to 50% similarity with that of other species except Gadus sp. Expression levels of GmAFPIV were found in a decreasing manner in liver, intestine, gill, brain and gonad. Heterologously expression of the GmAFPIV protein was expressed in Escherichia coli and purified to immunize New Zealand rabbits. The survivors of E. coli in 60 µg/mL of GmAFPIV are more than that in the 30 µg/mL group after stored in -20 °C and -80 °C, indicating high concentration of GmAFPIV could protect E. coli avoiding the damage from ice crystal. The subcellular localization of GmAFPIV showed that the green fluorescence was mainly observed in the cytoplasm, indicating GmAFPIV play roles in the cytoplasm. It was concluded that GmAFPIV may function not only as an antifreeze protein but also as an apolipoprotein transporting lipids in fish.

Network meta-analysis of surgical treatment for unstable femoral intertrochanteric fractures.

In this network meta-analysis, we determined the optimal surgical method for treating unstable femoral intertrochanteric fractures. We searched the EMBASE, Cochrane Library and Medline databases for studies evaluating sliding hip screws (SHS), gamma nail (GN) or proximal femoral nail antirotation (PFNA) methods, and included nine randomized controlled trials that met the inclusion criteria. Our analysis showed no differences in the rates of complications between SHS and PFNA relative to GN (p > 0.05). However, the surface under the cumulative ranking curve (SUCRA) score for PFNA (77.6%) was higher than the SUCRA scores for GN (65%) and SHS (7.5%). This suggests PFNA is the better surgical method than GN or SHS for unstable femoral intertrochanteric fractures.

Molecular characterization of caspase members and expression response to Nervous Necrosis Virus outbreak in Pacific cod.

Multiple functions of caspases include normal cell turnover, proper development and function of the immune system, hormone-dependent atrophy, embryonic development and chemical-induced cell injury. During artificial propagation of Pacific cod, Gadus macrocephalus, high mortality occurred during early development stages. Here, we performed various analyses on the cDNA and protein sequences of six different G. macrocephalus caspases namely GmCasp3, 6, 7, 8, 9 and 10, and tried to investigate the contributions of caspase family to the development and Nervous Necrosis Virus (NNV) resistance. Sequence analysis of GmCaspase proteins showed that each caspase shared conserved domains like "HG", "QACXG (X for R, G or Q)" and "GSWF" except GmCasp10. Sequence alignment and phylogenetic tree showed that GmCasp8 and GmCasp10 were quite different from those of other fishes. 3-D models indicated that structure of GmCasp3 is very conservative, but GmCasp6, 7, 8, 9 and 10 are less conservative. Tissue distribution analysis showed that six Gmcaspases mRNA transcripts were detected in tissues of intestine, gill, thymus, head-kidney and spleen with different abundance, but Gmcasp7 were not detected in the brain. GmCasp3 transcript was kept at very low level in the early development stages, while the expression levels of GmCasp6, 7, 8, 10 were different at various development stages. GmCasp8 level seemed to be much higher than other caspases in the heads of 65dph and 75dph juveniles. To understand the role of caspases during NNV outbreak, modulation in expression of each Gmcaspases were investigated. The results showed that GmCasp3 transcript level increased significantly when NNV broke out, while GmCasp7, 8, 9 and 10 in cod heads decreased obviously at 69dph and 77dph. The results suggest that caspases in Pacific cod should be diverse in their structure and function, and their unique features and response to NNV outbreak add more evidences for the specificity of immune system in Pacific cod.

Ni(ii)-based coordination polymers for efficient electrocatalytic oxygen evolution reaction.

The exploration of highly efficient, stable and cheap water oxidation electrocatalysts using earth-abundant elements is still a great challenge. Herein, alkaline-stable cationic Ni(ii) coordination polymers (Ni-CPs) were successfully obtained under hydrothermal conditions, which could stabilize the incorporation of Fe(iii) to form Fe-immobilized Fe@Ni-CPs. The newly developed Ni-based CPs were used for the first time as an effective electrocatalyst for the oxygen evolution reaction in strong alkaline media.

Digital gene expression analysis of Takifugu rubripes brain after acute hypoxia exposure using next-generation sequencing.

The adverse effects of hypoxia are confined to biochemical, physiological, developmental and behavioral processes, especially injury of the brain. In this study, a subset of genes in the brain of Takifugu rubripes were analyzed using digital gene expression (DGE) profiles and next-generation sequencing after acute hypoxia. Among 32 differentially expressed genes, 29 were up-regulated and 3 were down-regulated following hypoxia exposure. Using Gene Ontology analysis, it was found that transcription and translation, metabolism, and the stress response were affected by exposure to hypoxia. KEGG analysis revealed that the neuroactive ligand-receptor interaction pathway was significantly enriched in hypoxia-exposed T. rubripes. To further confirm the differential expression of genes, quantitative real-time PCR was performed to test six candidate genes, with the following five genes exhibiting the same expression patterns as the sequencing results: Proto-oncogene c-fos, Kruppel-like factor 2, immediate early response 2, proopiomelanocortin A and rhodopsin. This work is the first to identify and annotate genes in T. rubripes affected by hypoxia stress. This investigation provides data for understanding the molecular mechanism of fish adaptation to hypoxia and provides a reference for rationally setting dissolved oxygen levels in aquaculture.