Publications by authors named "Chun-feng Song"

Article Synopsis
  • The study investigates morphological variations and identifies a specific plant species by examining herbarium specimens and conducting field research in its type locality.
  • Findings indicate that a plant species originally from Nanchuan County, Chongqing, is actually the same as another species, which is found in various regions of China and Vietnam.
  • The research highlights key characteristics of leaves, inflorescences, and fruits that support this classification, proposing that one species should be considered a synonym of the other and clarifying its geographical distribution.
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Background: Tribe Oenantheae consists mainly of aquatic species within the Apioideae. The unique morphology and habitat distinguish this group from other Apioideae groups. However, the genomic information of these group species has not been widely developed, and the molecular mechanisms of adaptive evolution remain unclear.

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Article Synopsis
  • - The study investigates the phylogeny and evolution of the Hydrocotyle genus, which consists of about 170 species and is important for understanding the evolution of the Apiales group, by analyzing ten representative species for their genetic and morphological diversity.
  • - Plastome analysis reveals that the structure and gene order are generally conserved in Hydrocotyle, identifying 14 hotspot regions that could serve as DNA barcodes for further phylogenetic studies and highlighting the ycf15 gene as a potential identifying marker.
  • - Phylogenetic analysis identified three distinct clades within the genus, with evidence of rapid speciation, and detected six genes under positive selection, indicating adaptive evolution while maintaining a level of conservatism in certain
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was an important medicinal plant. The complete plastid genome of this species was reported for the first time. The full length of the complete chloroplast genome is 153,302 bp, with a typical quadripartite organization: a large single-copy (LSC) region of 84,417 bp, a small single-copy (SSC) region of 18,767 bp, and a pair inverted repeat regions (IR and IR) with 25,059 bp for each.

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Roundworm parasite infections are a major cause of human and livestock disease worldwide and a threat to global food security. Disease control currently relies on anthelmintic drugs to which roundworms are becoming increasingly resistant. An alternative approach is control by vaccination and 'hidden antigens', components of the worm gut not encountered by the infected host, have been exploited to produce Barbervax, the first commercial vaccine for a gut dwelling nematode of any host.

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The quality of bitumen directly affects road performance and road life. Traditional analytical methods-for wax content, softening point and penetration of bitumen are tedious and time-consuming. A new fast method, with which the three properties can be determined at same time, is proposed in this paper.

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A new method using reflection NIR technology was developed to determine the alcoholysis degree and volatile matter of Poly-vinyl alcohol (PVA). 120 samples were used in this research. NIR spectra of the sample were scanned by the spectrometer from 1 000 to 1 800 nm.

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A new analytical method of analyzing dimethyl ether (DME) content in liquefied petroleum gas (LPG) is proposed in this paper. An unsolved problem about quick detection of the composition of LPG has been settled with this method. A set of precise preparation apparatus for DME/ LPG solution and a set of quickly analytical system of LPG based on near infrared technology were designed.

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A new rapid quantitative method for the determination of oxygenates and the compounds not included in the national standard in gasoline using near-infrared spectroscopy is raised by this paper. This method combine near-infrared spectroscopy with oblique projection. This experiment choose four different types of gasoline, including reconcile gasoline, FCC refined gasoline, reformed gasoline and desulfurizing gasoline.

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A rapid discrimination method of edible oils, KL-BP model, was proposed by attenuated total reflectance infrared spectroscopy. The model extracts the characteristic of classification from source data by KL and reduces data dimension at the same time. Then the neural network model is constructed by the new data which as the input of the model.

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In the spectral analysis, a large-scale application of the traditional multivariate analysis methods has been limited by both high cost and poor applicability of the calibration models. A new multivariate analysis method was proposed for multicomponent systems in the present paper. Determining MTBE content in gasoline solution by infrared spectroscopy was studied.

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A new method is proposed for the fast determination of the induction period of gasoline using Fourier transform attenuated total reflection infrared spectroscopy (ATR-FTIR). A dedicated analysis system with the function of spectral measurement, data processing, display and storage was designed and integrated using a Fourier transform infrared spectrometer module and chemometric software. The sample presentation accessory designed which has advantages of constant optical path, convenient sample injection and cleaning is composed of a nine times reflection attenuated total reflectance (ATR) crystal of zinc selenide (ZnSe) coated with a diamond film and a stainless steel lid with sealing device.

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In the present paper, a new correction method of baseline drift of discrete spectrum is proposed by combination of cubic spline interpolation and first order derivative. A fitting spectrum is constructed by cubic spline interpolation, using the datum in discrete spectrum as interpolation nodes. The fitting spectrum is differentiable.

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A new method of near-infrared (NIR) diffuse reflectance spectroscopy is proposed to rapidly determine the degree of polymerization (DP) of natural cellulose (cotton and wood) pulp produced by a new clean pulping process. One hundred and ninety five samples were collected and their DP data were determined by standard method GB/T 9107-1999. The spectroscopy measurement method of the samples was studied and their near-infrared diffuse reflectance spectra were collected.

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A new actinomycete strain NA4 was isolated from a deep-sea sediment collected from the South China Sea and showed promising antifungal activities against soilborne fungal pathogens. It was identified as Streptomyces cavourensis by morphological, physiological, and phylogenetic analyses based on its 16S rRNA gene sequence. The main antifungal components were isolated and identified from the fermentation culture as bafilomycins B1 and C1.

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A set of rapid analysis system for hydrocarbon composition of heavy oils was designed using attenuated total reflection FTIR spectrometer and chemometrics to determine the hydrocarbon composition of furfural extract oils. Sixty two extract oil samples were collected and their saturates and aromatics content data were determined according to the standard NB/SH/T0509-2010, then the total contents of resins plus asphaltenes were calculated by the subtraction method in the percentage of weight. Based on the partial least squares (PLS), calibration models for saturates, aromatics, and resin+asphaltene contents were established using attenuated total reflection FTIR spectroscopy, with their SEC, 1.

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The side effects in spectral multivariate modeling caused by the uneven distribution of sample numbers in the region of the calibration set and validation set were analyzed, and the "average" phenomenon that samples with small property values are predicted with larger values, and those with large property values are predicted with less values in spectral multivariate calibration is showed in this paper. Considering the distribution feature of spectral space and property space simultaneously, a new method of optimal sample selection named Rank-KS is proposed. Rank-KS aims at improving the uniformity of calibration set and validation set.

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A rapid nondestructive method for identifying intact foods containing trans fatty acids (TFA) using diffuse near infrared spectroscopy (NIR) was proposed in the present paper. The diffuse Fourier transform near infrared (FT-NIR) spectra of intact samples were collected by fiber probe, and the reference data of TFA content were determined by Chinese standard method GB/T 22110-2008 (gas chromatography (GC) method). In this work, all the samples were classified into two categories: foods with TFA and foods without TFA according to the TFA content of the foods.

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The V-ATPase is a membrane-bound protein complex which pumps protons across the membrane to generate a large proton motive force through the coupling of an ATP-driven 3-stroke rotary motor (V1) to a multistroke proton pump (Vo). This is done with near 100% efficiency, which is achieved in part by flexibility within the central rotor axle and stator connections, allowing the system to flex to minimise the free energy loss of conformational changes during catalysis. We have used electron microscopy to reveal distinctive bending along the V-ATPase complex, leading to angular displacement of the V1 domain relative to the Vo domain to a maximum of ~30°.

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A new near infrared diffuse reflectance spectroscopy method is proposed to rapidly detect alpha-cellulose content of natural cellulose (plant fiber: cotton, wood) pulp in a new clean pulping process. One hundred forty two samples were collected and their alpha-cellulose content data were determined by standard method GB/T 9107-1999. The samples were homogenized by grinding pretreatment to improve spectroscopy measurement accuracy.

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A new quantitative method to determine the NH4H2PO4 in ABC powder extinguishing agent and to distinguish between ABC and BC powder extinguishing agents using near infrared diffuse reflectance spectroscopy is proposed. A PLS calibration model for the NH4H2PO4 content in extinguishing agent powder was established, with RMSECV = 2.1, RMSEP = 2.

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In the present paper, the distribution of sugar level within the mini-watermelon was studied, a new sugar characterization method of mini-watermelon using average sugar level, the highest sugar level and the lowest sugar level index is proposed. Feasibility of nondestructive determination of mini-watermenlon sugar level using diffuse reflectance spectroscopy information was investigated by an experiment. PLS models for measuring the 3 sugar levels were established.

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CO(2) capture and storage (CCS) is an important alternative to control greenhouse gas (GHG) effects. In previous work, a novel desublimation CO(2) capture process has been exploited making use of three free piston Stirling coolers (namely, SC-1, SC-2, and SC-3, respectively). Based on the developed system, moisture and CO(2) in the flue gas can condense and desublimate in the prefreezing and main-freezing towers, respectively.

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MLR and PLS models with or without OSC were studied through establishing quantitative calibration models for the peanut oil content in blending edible oils, and for the dimethylsulfoxide concentration in water solution. The cross validation results and the predication results of MLR models, were compared to evaluate the effectiveness of OSC for improving the performance of MLR model. The results show that the SEC or SEP of MLR models using OSC gets smaller.

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Article Synopsis
  • Type I DNA restriction/modification enzymes are crucial molecular machines in most bacteria, playing a key role in genetic engineering by managing the uptake of foreign DNA while modifying host DNA for protection.
  • These enzymes, like EcoKI and EcoR124I, undergo significant structural changes during function, transitioning from an open to a compact form when they bind DNA.
  • The research reveals these enzymes' structures and provides insights into the evolutionary connection between Type I and Type II restriction/modification enzymes through advanced imaging and molecular modeling techniques.
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