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Granular lost circulation materials (LCMs) are used to control fluid loss in naturally fractured thief zones. Rapid and automated identification of their optimal particle size distribution (PSD) is highly desirable. This paper proposes a PSD selection method for LCMs based on a PSD representation algorithm and the Monte Carlo method. The PSD representation algorithm describes the cumulative and compositional PSD curves of LCMs according to a piecewise cubic Hermite interpolation algorithm. Comparison with measured PSD data shows that the representation algorithm is more accurate than other commonly used PSD models in describing both homogeneous and mixed LCMs, and the relative errors are all within 10%. The Monte Carlo method is adopted to simulate LCMs with various compositions and select ones with PSDs that meet a proposed selection criterion. Experiments show that the PSD curves of the LCMs were all within the upper and lower bounds specified by the selection criterion. Plugging experiments show that LCMs with the recommended compositions can effectively enter fractures, and the fluid loss is less than 200 mL for half an hour under the pressure difference of 7 MPa. The proposed selection method can be used for the rapid and automatic design of granular LCMs used in fractured thief zones. • Common particle size distribution models are not suitable for complex systems. • Hermite interpolation is effective in describing the particle size distribution. • New selection method for particle size distribution are proposed and validated. • The selected lost circulation materials effectively reduce the fluid loss. [ABSTRACT FROM AUTHOR]

RBM39, also known as splicing factor HCC1.4, acts as a transcriptional coactivator for the steroid nuclear receptors JUN/AP-1, ESR1/ER-α and ESR2/ER-β. RBM39 is involved in the regulation of the transcriptional responses of these steroid nuclear receptors and promotes transcriptional initiation. In this paper, we report that RBM39 interacts with the nonreceptor tyrosine kinase c-Abl. Both the Src homology (SH) 2 and SH3 domains of c-Abl interact with RBM39. The major tyrosine phosphorylation sites on RBM39 that are phosphorylated by c-Abl are Y95 and Y99, as demonstrated by liquid chromatography coupled with tandem mass spectrometry (LC/MS/MS) and mutational analysis. c-Abl was shown boost the transcriptional coactivation activity of RBM39 for ERα and PRβ in a tyrosine kinase-dependent manner. The results suggest that mammalian c-Abl plays an important role in steroid hormone receptor-mediated transcription by regulating RBM39. [ABSTRACT FROM AUTHOR]

In the present work we address a simple, rapid and quantitative analytical method for detection of different proteins present in biological samples. For this, we proposed the model of titration of double protein (TDP) and its relevant leverage theory relied on the retardation signal of chip moving reaction boundary electrophoresis (MRBE). The leverage principle showed that the product of the first protein content and its absolute retardation signal is equal to that of the second protein content and its absolute one. To manifest the model, we achieved theoretical self-evidence for the demonstration of the leverage principle at first. Then relevant experiments were conducted on the TDP-MRBE chip. The results revealed that (i) there was a leverage principle of retardation signal within the TDP of two pure proteins, and (ii) a lever also existed within these two complex protein samples, evidently demonstrating the validity of TDP model and leverage theory in MRBE chip. It was also showed that the proposed technique could provide a rapid and simple quantitative analysis of two protein samples in a mixture. Finally, we successfully applied the developed technique for the quantification of soymilk in adulterated infant formula. The TDP-MRBE opens up a new window for the detection of adulteration ratio of the poor food (milk) in blended high quality one. [ABSTRACT FROM AUTHOR]

The effects of CaCO 3 on thermal and combustion characteristics of solid propellants composed of the novel green energetic material 5AT/Sr(NO 3 ) 2 are examined. Thermogravimetry–derivative thermogravimetry (TG–DTG), thermocouple measurements and closed bomb calorimetry are all employed to study the reaction mechanisms obtained when using CaCO 3 as a cooling additive. In this manner, the combustion temperatures, burning rates, pressure exponents, thermal behaviors and non-isothermal reaction kinetics of solid propellant specimens are assessed. The combustion of the 5AT/Sr(NO 3 ) 2 propellant with added CaCO 3 can be divided into two regions. The initial region is dominated by condensed phase reactions and exhibits a lower decomposition temperature, lower activation energy and higher burning rate. These results demonstrate that the addition of CaCO 3 increases the reactivity of the propellant. The latter region is primarily associated with gas phase reactions, and the decomposition temperature and activation energy all appear to be elevated in this region, although the exhaust gas temperature and burning rate are greatly reduced. The pressure exponent is also reduced significantly in this stage, providing evidence for increased combustion stability. The thermal characteristics of the decomposition reaction as observed microscopically indicate significant synergistic effects of the CaCO 3 on the burning behavior. CaCO 3 addition has been shown to generate a significant cooling effect and the combination of this compound with 5AT/Sr(NO 3 ) 2 results in a propellant with excellent thermal behavior and steady combustion. This propellant formulation is safe, scalable and inexpensive and therefore CaCO 3 appears to be an ideal agent for the modification of the gas generation performance of solid propellants. [ABSTRACT FROM AUTHOR]

Background Graves’ disease (GD) is recognized as a most frequent form of autoimmune thyroid disease, but the etiology underlying GD still remains unclear. Among the thyroid-specific and immune-modulating genes involved in susceptibility to GD, FCRL3 polymorphisms have been demonstrated to be associated with GD in independent studies. However, considering the limited sample size and statistical power of previous studies, there is no study analyzing this relationship systematically. Therefore, this investigation was aimed to perform a case-control study in a Chinese population and a meta-analysis including relevant studies was carried out to confirm a potential correlation between SNPs investigated and risk of GD. Methods and materials Seven single nucleotide polymorphisms (SNPs) were selected in this case-control study involved with 671 GD patients and 706 controls. Later, a meta-analysis including seven case-control studies related to GD susceptibility and FCRL3 polymorphisms was carried out. T -test and chi-square test were utilized to find if difference in clinical variables existed between case and control subjects. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to assess the association between GD susceptibility and FCRL3 polymorphisms. Results Three polymorphisms, namely, FCRL3_3 C, FCRL3_5 C and FCRL3_6 A, were significantly associated with increased risk of GD in terms of a Chinese Han population in both dominant model [OR = 1.33 (95% CI: 1.04–1.69), OR = 1.34 (95% CI: 1.05–1.70) and OR = 1.36 (95% CI: 1.07–1.75), respectively] and allelic model [OR = 1.27 (95% CI: 1.10–1.48), OR = 1.28 (95% CI: 1.11–1.49) and OR = 1.23 (95% CI: 1.06–1.43), respectively]. Further meta-analyses indicated that the effects of FCRL3_3 C, FCRL3_5 C and FCRL3_6 A on susceptibility to GD varied between Asians and Caucasians. Conclusions This case-control analysis demonstrated that FCRL3_3 , FCRL3_5 and FCRL3_6 polymorphisms were associated with significantly elevated risk of GD in a Chinese population. Furthermore, the following meta-analysis confirmed that FCRL3_3 , FCRL3_5 and FCRL3_6 polymorphisms could increase susceptibility to GD only in Asians, rather than in Caucasians. [ABSTRACT FROM AUTHOR]

A novel modified chitosan adsorbent (GL-SBCS) was synthesized by covalently grafting a Schiff base-chitosan (SBCS) onto the surface of l -monoguluronic acid. Physico-chemical investigation on the adsorption of congo red, an anionic azo dye by GL-SBCS has been carried out. The effect of different weight contents of chitosan in GL-SBCS composite, adsorbent dosage, initial pH and contract time were studied in detail using batch adsorption. Results showed that GL-SBCS exhibited better than normal CS and l -monoguluronic acid. Further investigation demonstrated that the adsorption pattern fitted well with the Langmuir model ( R 2 > 0.99) but less-satisfied the Freundlich model. Both ionic interaction as well as physical forces is responsible for binding of congo red with GL-SBCS as determined by zeta potential measurement Both sodium chloride and sodium dodecyl sulfate significantly influenced the adsorption process. SBCS would be a good method and resource to increase absorption efficiency for the removal of anionic dyes in a wastewater treatment process. [ABSTRACT FROM AUTHOR]

The traditional recycling free-flow isoelectric focusing (RFFIEF) suffered from complex structure, tedious operations and poor extensibility as well as high cost. To address these issues, a novel reciprocating free-flow isoelectric focusing device (ReFFIEF) was developed for proteins or peptides pre-fractionation. In the new device, a reciprocating background flow was for the first time introduced into free flow electrophoresis (FFE) system. The gas cushion injector (GCI) used in the previous continuous free-flow electrophoresis (CFFE) was redesigned for the reciprocating background flow. With the GCI, the reciprocating background flow could be achieved between the GCI, separation chamber and transient self-balance collector (tSBC). In a run, process fluid flowed to and from, forming a stable reciprocating fluid flow in the separation chamber. A pH gradient was created within the separation chamber, and at the same time proteins were focused repeatedly when passing through the chamber under perpendicular electric field. The ReFFIEF procedure was optimized for fractionations of three model proteins, and the optimized method was further used for pre-fractionation of model human serum samples. As compared with the traditional RFFIEF devices developed about 25 years ago, the new ReFFIEF system showed several merits, such as simple design and structure, user-friendly operation and easy to extend as well as low cost. [ABSTRACT FROM AUTHOR]

Specific biomarkers are urgently needed for the detection and progression of oral cancer. The objective of this study was to discover cancer biomarkers from oral epithelium through utilizing high throughput quantitative proteomics approaches. Morphologically malignant, epithelial dysplasia, and adjacent normal epithelial tissues were laser capture microdissected (LCM) from 19 patients and used for proteomics analysis. Total proteins from each group were extracted, digested and then labelled with corresponding isobaric tags for relative and absolute quantitation (iTRAQ). Labelled peptides from each sample were combined and analyzed by liquid chromatography-mass spectrometry (LC-MS/MS) for protein identification and quantification. In total, 500 proteins were identified and 425 of them were quantified. When compared with adjacent normal oral epithelium, 17 and 15 proteins were consistently up-regulated or down-regulated in malignant and epithelial dysplasia, respectively. Half of these candidate biomarkers were discovered for oral cancer for the first time. Cornulin was initially confirmed in tissue protein extracts and was further validated in tissue microarray. Its presence in the saliva of oral cancer patients was also explored. Myoglobin and S100A8 were pre-validated by tissue microarray. These data demonstrated that the proteomic biomarkers discovered through this strategy are potential targets for oral cancer detection and salivary diagnostics. [ABSTRACT FROM AUTHOR]

Negative bias temperature instability (NBTI) has become a serious reliability issue, and the interface traps and oxide charges play an important role in the degradation process. In this paper, we study the recovery of NBTI systemically under different conditions in the P-type metal–oxide–semiconductor field effect transistor (PMOSFET), explain the various recovery phenomena, and find the possible processes of the recovery. [ABSTRACT FROM AUTHOR]

Herein, a novel strategy was developed to separate and prepare target protein from complex sample by free-flow electrophoresis (FFE), which mainly based on the charge-to-mass ratio ( C / M ) analysis of proteins. The C / M values of three model proteins, namely Cytochrome C (Cyt C), myoglobin (Mb) and bovine serum albumin (BSA) were analyzed under different pH and the separation of these proteins was predicted by CLC Protein Workbench software. Series of experiments were performed to validate the proposed method. The obtained data showed high accordance with our prediction. In addition, the chamber buffer (CB) of FFE system was optimized to improve the resolution of separation. Meanwhile, in order to evaluate the analytical performance of the proposed method, Cyt C was extracted from swine heart and further separated by FFE based on C / M analysis. Results showed that Cyt C was completely separated from the crude sample and a purity of 96.9% was achieved. The activity of prepared Cyt C was 98.3%, which indicate that the proposed method is promising in a wide variety of research areas where the native properties of proteins should be maintained for downstream analysis. [ABSTRACT FROM AUTHOR]

Routine native immobilized pH gradient isoelectric focusing (IPG-IEF) and two-dimensional gel electrophoresis (2DE) are still suffering from unfortunate reproducibility, poor resolution (caused by protein precipitation) and instability in characterization of intact protein isoforms and posttranslational modifications. Based on the concept of moving reaction boundary (MRB), we firstly proposed a tunable non-IPG-IEF system to address these issues. By choosing proper pairs of catholyte and anolyte, we could achieve desired cathodic and anodic migrating pH gradients in non-IPG-IEF system, effectively eliminating protein precipitation and uncertainty of quantitation existing in routine IEF and 2DE, and enhancing the resolution and sensitivity of IEF. Then, an adjustable 2DE system was developed by combining non-IPG-IEF with polyacrylamide gel electrophoresis (PAGE). The improved 2DE was evaluated by testing model proteins and colon cancer cell lysates. The experiments revealed that (i) a tunable pH gradient could be designed via MRB; (ii) up to 1.65 fold improvement of resolution was achieved via non-IPG-IEF; (iii) the sensitivity of developed techniques was increased up to 2.7 folds; and (iv) up to about 16.4% more protein spots could be observed via the adjustable 2DE as compared with routine one. The developed techniques might contribute to complex proteome research, especially for screening of biological marker and analysis of extreme acidic/alkaline proteins. [ABSTRACT FROM AUTHOR]

We propose an implementation scheme for a TYPE-I M-LVDS receiver based on TIA/EIA-899 standard. A novel common-mode voltage shift circuits Is designed to realize an input common-mode range that Is beyond the rail of the power voltage, which can simplify the post stage circuit, thus saving area and power consumption. The pre-amplifier in the receiver can provide a fixed magnification for input signals, and the hysteresis comparator brings hysteresis effect to the system. The chip Is fabricated in GSMC 0. 18 ！m 1P6M CMOS technology, and the test results indicate that the receiver has an input common-mod range of --1. 4 V〜3. 8 V, a signaling rate greater than 250 Mbps, and a typical hysteresis voltage is 28 mV. [ABSTRACT FROM AUTHOR]

A concise and efficient one-pot synthesis of functionalized [1,8]naphthyridine derivatives via a three-component domino reaction of glutaraldehyde, malononitrile, and β-ketoamides, under catalyst-free conditions in an environmentally friendly medium (ethanol) is described. The main advantages of this protocol are short reaction times, practical simplicity, high yields, catalyst-free conditions, cheap and benign solvents, and high regio- and stereo-selectivities. [ABSTRACT FROM AUTHOR]

To solve the problems of that composite base bleed propellant grain (CBBPG) is crushed and unstably combusts during launching, a protection strategy is proposed by directly installing a magnesium combustible liner ( MCL) with temporary strength protection and auxiliary combustion in the inner hole of CBBPG. The FEM analysis model of CBBPG' s launching process in extreme working conditions is established by using ABAQUS, and the dynamic shooting contrast verification test is done. The simulation results show that MCL can effectively prevent CBBPG from excessively deforming during launching. At the same time, the test results show that the average velocity of the projectiles with MCL is increased by 4. 97 m/s, and the combustion consistency and combustion stability of CBBPG are both improved. [ABSTRACT FROM AUTHOR]

Drugs that can protect against organ damage are urgently needed, especially for diseases such as sepsis and brain stroke. We discovered that terazosin (TZ), a widely marketed α1-adrenergic receptor antagonist, alleviated organ damage and improved survival in rodent models of stroke and sepsis. Through combined studies of enzymology and X-ray crystallography, we discovered that TZ binds a new target, phosphoglycerate kinase 1 (Pgk1), and activates its enzymatic activity, probably through 2,4-diamino-6,7-dimethoxyisoquinoline′s ability to promote ATP release from Pgk1. Mechanistically, the ATP generated from Pgk1 may enhance the chaperone activity of Hsp90, an ATPase known to associate with Pgk1. Upon activation, Hsp90 promotes multistress resistance. Our studies demonstrate that TZ has a new protein target, Pgk1, and reveal its corresponding biological effect. As a clinical drug, TZ may be quickly translated into treatments for diseases including stroke and sepsis. [ABSTRACT FROM AUTHOR]

With a given free-flow electrophoresis device, reasonable conditions (electric field strength, carrier buffer conductivity, and flow rate) are crucial for an optimized separation. However, there has been no experimental study on how to choose reasonable general conditions for a free-flow electrophoresis device with a thermoelectric cooler in view of Joule heat generation. Herein, comparative experiments were carried out to propose the selection procedure of general conditions in this study. The experimental results demonstrated that appropriate conditions were (i) <67 V/cm electric field strength; (ii) lower than 1.3 mS/cm carrier buffer conductivity (Tris-HCl: 20 mM Tris was titrated by HCl to pH 8.0); and (iii) higher than 3.6 mL/min carrier buffer flow rate. Furthermore, under inappropriate conditions (e.g. 400 V voltage and 40 mM Tris-HCl carrier buffer), the free-flow electrophoresis separation would be destroyed by bubbles caused by more Joule heating. Additionally, a series of applications under the appropriate conditions were performed with samples of model dyes, proteins (bovine serum albumin, myoglobin, and cytochrome c), and cells ( Escherichia coli, Streptococcus thermophilus, and Saccharomyces cerevisiae). The separation results showed that under the appropriate conditions, separation efficiency was obviously better than that in the previous experiments with randomly or empirically selected conditions. [ABSTRACT FROM AUTHOR]

At embryonic stages, Olig3 is initially expressed in the dorsal-most region of the spinal cord, but later in the ventral marginal zone as well. Previous studies indicated that Olig3 controlled the patterning of dorsal spinal cord and loss of Olig3 function led to the re-specification of dI2 and dI3 neurons into dI4 interneurons. However, the role of Olig3 in regulating the development of ventral spinal cord has remained unknown. BrdU labeling demonstrated that ventral Olig3 was expressed in the post-mitotic neurons and Olig3+ cells seen at late embryonic stages were born at the earlier stage but remained in the marginal zone throughout embryogenesis. Loss-of-function and gain-of-function experiment indicated that Nkx2.2 regulated the expression of Olig3 in V3 interneurons. However, Olig3 mutation didn’t apparently affect the generation and migration of ventral neurons. These findings suggest that Olig3 plays different roles in regulating the development of dorsal and ventral spinal cord. [ABSTRACT FROM AUTHOR]

The spindle assembly checkpoint kinase Mps1 is highly expressed in several types of cancers, but its cellular involvement in tumorigenesis is less defined. Herein, we confirm that Mps1 is overexpressed in colon cancer tissues. Further, we find that forced expression of Mps1 in the colon cancer cell line SW480 enables cells to become resistant to both Mps1 inhibition-induced checkpoint depletion and cell death. Overexpression of Mps1 also increases genome instability in tumor cells owing to a weakened spindle assembly checkpoint. Collectively, our findings suggest that high levels of Mps1 contribute to tumorigenesis by attenuating the spindle assembly checkpoint. [ABSTRACT FROM AUTHOR]

Bone marrow mesenchymal stem cells (BMSCs) are multipotent stem cells. Finding methods to improve the osteogenic potential of these cells is a key factor in bone tissue engineering. Platelet-rich plasma (PRP) contains powerful growth factors that produce changes in a variety of cell types. The purpose of this study was to explore the effects of PRP on the osteogenic differentiation of BMSCs in vitro. Rabbit BMSCs were harvested and cultured in vitro in control media or in media enhanced with PRP. BMSCs began to attach 12-24 hours after seeding. A MTT assay demonstrated that PRP-induced BMSCs grew rapidly compared with the control group. The PRP group also showed strongly positive staining of alkaline phosphatase and mineralized nodules whereas the control group showed negative staining. However, the alkaline phosphatase activity and the mRNA level of the osteogenic markers (osteocalcin and osteopontin) remained higher in the PRP group. These results confirmed that PRP could enhance the proliferation of BMSCs and effectively promote the osteogenic differentiation of BMSCs in vitro. [ABSTRACT FROM AUTHOR]

The title compounds (III) and (V) are efficiently obtained by cascade reaction of isatins with enaminones. [ABSTRACT FROM AUTHOR]

The influence of PMOSFET gate length on the parameter degradation relations under negative bias temperature instability (NBTI) stress is studied. The threshold voltage degradation increases with reducing the gate length. By calculating the relations between the threshold voltage and the linear/saturation drain current, we obtain their correlation coefficients. Comparing the test result with the calculated linear/saturation current value, we obtain the ratio factors. The ratio factors decrease differently when the gate length diminishes. When the gate length reduces to some degree, the linear ratio factor decreases from greater than 1 to nearly 1, but the saturation factor decreases from greater than 1 to smaller than 1. This results from the influence of mobility and the velocity saturation effect. Moreover, due to the un-uniform distribution of potential damages along the channel, the descending slopes of the curve are different. [ABSTRACT FROM AUTHOR]

• The detonation behaviors in annular tubes with circular obstacles was investigated experimentally. • Smoked foil technique was adopted to record the cellular pattern evolution. • The diffraction-retonation of detonation wave was analyzed in detail. • Special vertical bands was observed, and the formation mechanism of which was analyzed. Experiments were performed to investigate the detonation behaviors of stoichiometric hydrogen-oxygen mixtures (at sub-atmospherical pressures) in annular tubes with circular obstacles. The annular tube was 1000 mm long and 48 mm in diameter (D). The circular obstacles were with the diameters of 37.20 mm and 30.36 mm, corresponding to the BR = 0.57, 0.36 (BR : blockage ratio), respectively. Two types of obstacle spacing S was set in the test, which are S = D and S = 2 D. The detonation velocities were obtained based on the time of arrival of the wave front monitored by pressure transducers. Smoked foils were used to register the detonation cellular evolution though the test section. The results showed that the propagation limit in this test was 2 ω / λ ≈ 1 (ω indicates the channel width, λ represents the cell width), which was consistent with the previous results in round tubes with orifice plates. The obstacle spacing presented no noticeable effect on detonation propagation limit. However, it played a significant role on detonation velocity. What is more, larger flow blockage for BR = 0.57 caused the more violent velocity fluctuation and higher propagation limit than in smaller blocking ratio. The process of diffraction-retonation for interaction between wave front and obstacle was analyzed in detail. In further, special vertical bands with periodic variation characteristic were observed between two adjacent obstacles. The vertical bands were spaced as same as the obstacle spacing and attached very fine cells which were caused by the head-on collision of the detonation wave propagating in the compressed region with high temperature and pressure. [ABSTRACT FROM AUTHOR]

[Display omitted] • Uniaxial compression strength is suited as design index based on rutting resistance. • Asphalt mix from proposed method has more coarse aggregate and lower asphalt dosage. • Design system is built by combining uniaxial compression strength with design method. • Rutting resistance of asphalt mix can be enhanced by using established design system. The objective of this study is to establish a design system oriented towards the rutting resistance of paving asphalt mixture. To achieve this goal, a series of experiments and analyses were conducted, including the selection of design parameter, the establishment of design method and the verification of design system. Test results indicated that in comparison with uniaxial penetration strength (UPS) and Marshall stability (MS), uniaxial compression strength (UCS) had a higher sensitivity to asphalt content and was thus suitable as a design parameter. Correlation analysis showed that linear correlation between UCS and dynamic stability was more significant with Pearson correlation coefficient (PCC) exceeding 0.8 for various types of asphalt mix, exhibiting an accurate characterization to the anti-rutting ability of asphalt mix. Moreover, 2.94 MPa was proposed as the design critical value based on fitting equation. Compared to conventional design method, the asphalt mixture from proposed method possessed a better high-temperature performance, especially under severe in-service condition where flow number increased by 27.5% to 37.1% in repeated load permanent deformation (RLPD) test and impression depth decreased by 18.3% to 19.7% in Hamburg wheel tracking (HWT) test. This research provided a new idea for anti-rutting technology innovation of asphalt pavement in civil airport field from the aspect of paving materials design. [ABSTRACT FROM AUTHOR]

[Display omitted] • The δ7Li compositions imply the surface runoff should be the major source of Li in Xinmin bauxite deposit. • Illite and kaolinite are the main host minerals of Li in Xinmin bauxite deposit, and chlorite are not. • The enrichment of Li occurred at the primary bauxitic materials formation stage. Most bauxites in China can be classified as the paleoweathering crust sedimentary type (PCS type) and are normally enriched with lithium (Li). However, the source, host minerals, and enrichment mechanism of Li in bauxites are poorly understood. This study takes the Xinmin bauxite deposit, a typical PCS type in northern Guizhou, China, as a case to trace the Li source and its enrichment using Li isotopes. The Xinmin bauxite deposit is a typical PCS type deposit with high Li contents (average = 756 × 10−6) and heavy Li isotopic compositions (δ7Li) (average = 0.83‰). The Hanjiadian Formation's silty shale (S 1–2 hj) and the Huanglong Formation's limestone (C 2 h) are the parent rocks of the Xinmin bauxite deposit. The Dazhuyuan Formation (P 1 d), as bauxite-bearing rocks of the Xinmin bauxite deposit, was formed via diagenesis from the parent rocks' weathering products. According to the Li isotope fractionation mechanism under chemical weathering, the Dazhuyuan Formation (P 1 d) should have a lighter δ7Li than parent rocks. However, the δ7Li of the Dazhuyuan Formation (P 1 d) is heavier than that of parent rocks, indicating that the Dazhuyuan Formation's original δ7Li was altered by adding external-source Li characterized by heavy δ7Li. Considering the sedimentary environment and Li isotopes, this study proposes that the Li carried by surface runoff characterized by heavy δ7Li is the main source of Li in the Xinmin bauxite deposit. The correlations between clay minerals vs. Li contents and δ7Li show that illite and kaolinite may be the major host minerals of Li in the Xinmin bauxite deposit. Furthermore, the positive correlations of Li vs. Na 2 O and MgO indicate that smectite is another possible Li host mineral. Combined with the formation process of a PCS type bauxite deposit, this study proposes that Li enrichment occurs during the primary bauxitic material formation stage. During this stage, the Li carried by surface runoff converged into the coastal restricted basin where the primary bauxitic materials were deposited. After small-scale transgression, retention water formed in the basin with the rise in the groundwater table. The retained water evaporated under a hot and dry climate, and Li carried by surface runoff accumulated in the basin and was finally adsorbed by clay minerals such as illite, kaolinite, and smectite in the primary bauxitic materials. This mechanism can significantly increase Li contents and δ7Li in the PCS type bauxite deposit. Additionally, this mechanism implies that the migration process of Li in surface runoff during the formation of primary bauxitic materials determined the present Li contents and δ7Li of a PCS type bauxite deposit, mainly controlled by the sedimentary environment and hydrologic and climatic conditions at that time. [ABSTRACT FROM AUTHOR]

Two novel aporphine related alkaloids, fissitungfines A ( 1 ) and B ( 2 ), together with two known biogenetically related alkaloids, nornuciferine ( 3 ) and annonaine ( 4 ), were isolated from the stems of Fissistigma tungfangense . Fissitungfines A ( 1 ) and B ( 2 ) were a new type of aporphine related alkaloids, possessing an unprecedented skeleton in which one six-membered carbocyclic ring in classic aporphine alkaloid was replaced by one six-membered lactone ring. Their structures were elucidated on the basis of spectroscopic data. A plausible biogenetic pathway for this new type of aporphine related alkaloid is also proposed. [ABSTRACT FROM AUTHOR]

Uneven flow in free-flow electrophoresis (FFE) with a gravity-induced fraction collector caused by air bubbles in outlets and/or imbalance of the surface tension of collecting tubes would result in a poor separation. To solve these issues, this work describes a novel collector for FFE. The collector is composed of a self-balance unit, multisoft pipe flow controller, fraction collector, and vacuum pump. A negative pressure induced continuous air flow rapidly flowed through the self-balance unit, taking the background electrolyte and samples into the fraction collector. The developed collector has the following advantages: (i) supplying a stable and harmonious hydrodynamic environment in the separation chamber for FFE separation, (ii) effectively preventing background electrolyte and sample flow-back at the outlet of the chamber and improving the resolution, (iii) increasing the preparative scale of the separation, and (iv) simplifying the operation. In addition, the cost of the FFE device was reduced without using a multichannel peristaltic pump for sample collection. Finally, comparative FFE experiments on dyes, proteins, and cells were carried out. It is evident that the new developed collector could overcome the problems inherent in the previous gravity-induced self-balance collector. [ABSTRACT FROM AUTHOR]

Herein, a simple assembly was designed via a capillary and a funnel-like cap to achieve liquid–gas compound pendant drop (CPD) microextraction with great convenience. Due to the increased contact area and adhesion force between the capillary tip and the drop, the proposed method provides considerable flexibility in producing CPDs with different air bubble sizes. Four pesticides were chosen as model analytes to evaluate the proposed method. By using a 1 μL chlorobenzene droplet containing a 1 μL air bubble at a stirring rate of 700 rpm, a 70 to 135-fold enrichment of pesticides was obtained within 3.4 minutes. As compared with a typical SDME, the proposed method showed a 2-fold increase of enrichment factors and a 4-fold decrease of extraction time. Improvement of the extraction efficiency could be ascribed to the increased surface area of the droplet, and the thin film phenomena further improved the extraction kinetics through effective agitation. The results indicate that CPD microextraction could serve as a promising sample pretreatment method for automated high-throughput analyses in a wide variety of research areas. [ABSTRACT FROM AUTHOR]

Abstract: The chemoselective reduction of several structurally diverse compounds containing carbonyl groups was achieved in the presence of low-valent titanium reagents. This novel synthetic method provides easy access to highly selective reduction of carbonyl groups, and possesses several advantages including one-step procedure, convenient manipulation, good to excellent yields, and short reaction times. [Copyright &y& Elsevier]

Highlights: [•] Thermoelectric coolers and ceramic plate combined as temperature control system for stable long-term run of FFE for the first time. [•] Simple fastening structure designed for easy assembly of FFE device with good anti-leakage ability within 3min. [•] Simple and rapid method for exhausting air bubble in FFE within 5s. [•] An electroconductive membrane with about 90% efficiency of voltage usage in FFE. [ABSTRACT FROM AUTHOR]

Abstract: A simple capillary array IEF device was developed for high resolution and micropreparative separation of trace amounts of proteins. Based on quasi-chip-scale manufacturing, the specific capillaries (600μm i.d., 1200μm o.d. and 20mm length) were integrated with the miniaturized polymethyl-methacrylate electrode trays. Electroosmotic flow was suppressed effectively by modified cross-linked polyacrylamide coating, and instability of IEF was addressed using the designed concentration of electrolytes via moving reaction boundary theory. As a prototyping, the resolution, reproducibility, throughput, speed and linearity of pH gradient were systemically evaluated with model proteins. The results revealed the following advantages: (i) the reproducibility of array was assessed as RSD values of 0.95% (intra-day) and 2.88% (inter-day); (ii) IEF could be completed in 20min with up to 400V/cm electric field; (iii) high resolution separation of model proteins achieved in 20mm length column; (iv) multi-units with 48 micro-columns can be easily integrated to obtain high throughput; and (v) good linearity of pH gradient (R=0.9989). More importantly, utility of the device was tested by using hemoglobins sample from human red blood cell. HbA0 and HbA1c with only ΔpI 0.03 have been successfully separated by the developed method. [Copyright &y& Elsevier]

Abstract: Hemoglobin A1c (HbA1c) has been proven to be a key biomarker for diabetes screening, and glutathiolation of HbA1c (viz., GSS-HbA1c) has been identified. However, the impact of GSS-HbA1c on the measurement of HbA1c for diabetes screening has not been quantitatively assessed yet. To address the issue, the micropreparative capillary isoelectric focusing (cIEF) developed in our previous work was used for the high resolution separation and purification of hemoglobin (Hb) species. The main fractions of HbA0, HbA3 and HbA1c extracted from the developed cIEF were identified by validated Mono S method. The proposed GSS-HbA1c fractions in the cIEF were pooled and identified by electrospray ionization mass spectrometry (ESI-MS). The HbA1c enzyme-linked immunosorbent assay (ELISA) kit was employed for further quantitative analysis of GSS-HbA1c. A total of 34 blood samples with HbA1c levels from 4.2% to 13.4% were assessed via the above comprehensive strategy of IEF-HPLC-MS-ELISA. It was demonstrated that the HbA1c levels detected by cation exchange LC were considerably influenced by the glutathiolation of Hb and the range of detected GSS-HbA1c values was between 0.23% and 0.74%. The results and developed cIEF methods have considerable significances for investigation of diabetes and clinical diagnosis. [Copyright &y& Elsevier]

We developed a novel polyacrylamide gel electrophoresis (PAGE) method to stack and separate human hemoglobins (Hbs) based on the concept of moving reaction boundary (MRB). This differs from the classic isotachophoresis (ITP)-based stacking PAGE in the aspect of buffer composition, including the electrode buffer (pH 8.62 Tris-Gly), sample buffer (pH 6.78 Tris-Gly), and separation buffer (pH 8.52 Tris-Gly). In the MRB-PAGE system, a transient MRB was formed between alkaline electrode buffer and acidic sample buffer, being designed to move toward the anode. Hbs carried partial positive charges in the sample buffer due to its pH below p I values of Hbs, resulting in electromigrating to the cathode. Hbs would carry negative charges quickly when migrated into the alkaline electrode buffer and be transported to the anode until meeting the sample buffer again. Thus, Hbs were stacked within a MRB until the transient MRB reached the separation buffer and then separated by zone electrophoresis with molecular sieve effect of the gel. The experimental results demonstrated that there were three clear and sharp protein zones of Hbs (HbA, HbA, and HbA) in MRB-PAGE, in contrast to only one protein zone (HbA) in ITP-PAGE for large-volume loading (≥15 μl), indicating high stacking efficiency, separation resolution, and good sensitivity of MRB-PAGE. In addition, MRB-PAGE was performed in a conventional slab PAGE device, requiring no special device. Thus, it could be widely used in separation and analysis of diluted protein in a standard laboratory. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

In this paper, a mathematical model was proposed for calculating physico-chemical parameters and simulating the separation process of solutes in free-flow zone electrophoresis (FFZE). Computer software was developed and implemented in a Delphi XE2 environment based on the model, which comprises zone electrophoresis, electrolyte solution, hydrodynamics and diffusion as well as conversion equations. The simulation results reveal that (i) the software is capable of simulating a dynamic process of FFZE properly; (ii) the software can simulate operation parameters (e.g., electric field, flow rate and pH value) for experimental optimization; (iii) the simulator is able to display the final electropherogram of numerous analytes in FFZE; and (iv) the electropherogram of FFZE can be automatically converted to that of capillary zone electrophoresis. In order to verify the rationality and reliability of this software, the relevant experiments were conducted and further compared with the simulations. The comparisons demonstrated the high agreement between the simulations and the experiments as well as those cited from the relevant references. In addition, effective mobility, diffusion coefficient and concentration of solutes can be conveniently gained via the software. The developed mathematical model and designed software have evident significance for the optimization of experimental conditions and basic physico-chemical parameters in FFZE. [ABSTRACT FROM AUTHOR]

In this paper, a general mode and theory of moving chelation boundary based isotachophoresis (MCB-based ITP), together with the concept of decisive metal ion (DMI) having the maximum complexation constant (lg Kmax) with the chelator, were developed from a multi-MCB (mMCB) system. The theoretical deductions were: (i) the reaction boundary velocities in the mMCB system at steady state were equal to each other, resulting in a novel MCB-based ITP separation of metal ions; (ii) the boundary directions and velocities in the system were controlled by the fluxes of chelator and DMI, rather than other metal ions; and (iii) a controllable stacking of metal ions could be simultaneously achieved in the developed system. To demonstrate the deductions, a series of experiments were conducted by using model chelator of EDTA and metal ions of Cu(ii) and Co(ii) due to characteristic colors of blue [Cu–EDTA]2− and pink [Co–EDTA]2− complexes. The experiments demonstrated the correctness of theoretical deductions, indicating the validity of the developed model and theory of ITP. These findings provide guidance for the development of MRB-based ITP separation and stacking of metal ions in biological sample matrix and heavy metal ions in environmental samples. [ABSTRACT FROM AUTHOR]

Abstract: A mild and efficient one-pot protocol for the preparation of 8,13-dihydro-7H-indolo[2′,3′:3,4]pyrido[1,2-b]indazole and 5,6-dihydroindazolo[3,2-a]isoquinoline via the reductive cyclization of nitro-aryl substrates mediated by a low-valent titanium reagent has been developed. The attractive features of the current method include an N–N bond formation and the selective reduction of the C N bond and nitro group, both of which were easily achieved in one-pot by controlling the pH of the reaction mixture. [Copyright &y& Elsevier]

[Display omitted] • Degradation of OG by DBD combined with PS, SPC and Fe(VI) was investigated. • Fe(VI) showed higher degradation efficiency and energy yield in promoting OG degradation. • After adding the oxidant, the synergy factor was greater than 1. • The synergistic mechanism of OG degradation was researched. A coupling technique of introducing an oxidant into dielectric barrier discharge (DBD) plasma was studied to enhance the degradation of Orange G (OG) in aqueous solution. We evaluated the main effect of oxidants on the degradation of OG. Experiments showed that an appropriate amount of oxidant in DBD showed a significant synergistic effect, which improved the degradation efficiency and kinetics of OG. Increasing the voltage was beneficial to promote the degradation of OG. After 10 min of treatment, when the PS, SPC and Fe(VI) were 0.15, 0.10, 0.10 mM and the voltage was 70 V for 100 mg/L OG, the degradation efficiency reached 64.6%, 81.7% and 96.5%, respectively. After adding the oxidant, the synergy factor was greater than 1, and the energy yield got improvement. In addition, the quantitative determination of H 2 O 2 and O 3 and free radical scavenger test explained its mechanism of reaction. The results confirmed that the addition of oxidants could increase the production of active species, and the production of active substances had a significant impact on the removal of OG. The results showed that the addition of Fe(VI) showed higher degradation efficiency and energy yield in promoting OG degradation, while the effect of adding PS was relatively weak. [ABSTRACT FROM AUTHOR]

Abstract: An immobilized pH gradient (IPG) has strong power against instability (e.g., drifting and plateau) existing in classic isoelectric focusing (IEF). However, the relevant mechanism against the instability of pH gradient is still unclear. In this work, the theories of diffusional current and water products in IEF were developed based on the Svensson–Tiselius's differential equation and concept of moving reaction boundary (MRB). Two novel methods of pH gradient mobilization in IPG–IEF and non-IPG–IEF (opposite to IPG–IEF) were developed to unveil stability mechanism of IPG–IEF. The theoretical and experimental results indicated that (i) the drifting of pH gradient in non-IPG–IEF could be effectively controlled by IPG technique due to the existence of equal-fluxes of hydroxyl and hydrogen ions in the IPG–IEF system, (ii) there existed high diffusional current in non-IPG–IEF because of the existence of free carrier ampholyte (CA), but weak current in the IPG–IEF due to the immobilization of CA species in gel matrix, and (iii) the high diffusional current resulted in a great amount of water formation in neutral zone of pH gradient that led to distinct plateau in non-IPG–IEF, conversely the weak diffusional current caused little of water formation and weak plateau of pH gradient in IPG–IEF. These studies have considerable significance to the understanding of mechanism and development of protein IEF separation technique. [Copyright &y& Elsevier]

As two important physico-chemical parameters, the acidic and alkaline residues of protein are of evident significance for the evaluation of protein properties and the design of relevant separation and analysis. However, there is still no electrophoretic method used for the direct detection of free acidic and alkaline residues of protein. Herein, we developed the concepts of moving reaction boundary (MRB) and MRB titration, relevant MRB titration theory, and the method of microdevice electrophoresis for the determination of free acidic and alkaline residues of protein. In the MRB titration, the boundary was created with acid or alkali and target protein immobilized via highly cross-linked polyacrylamide gel (PAG). It was theoretically revealed that the number of free acidic or alkaline residues of protein was as a function of MRB displacement in the electrophoretic titration system. As a proof of concept, seven model proteins were chosen for the determination of acidic or alkaline residues of protein via MRB titration. The results showed that the numbers of free acidic and alkaline residues of proteins detected were in good agreement with those obtained from the relevant amino sequences in the NCBI database, demonstrating the feasibility of the developed concept, theory and technique. The general methodology of MRB titration has potential application for inexpensive, facilitative and informative protein structure analysis of free acidic or alkaline residues of protein. [ABSTRACT FROM AUTHOR]

Highlights: [•] A novel moving reaction boundary model formed with base and immobilized protein. [•] The moving reaction boundary titration developed for protein content assay. [•] Determining protein content via visual boundary displacement signal. [•] Weak influence of non-protein nitrogen reagents on the developed method. [•] Fast and sensitive analytical method as compared with classic Kjeldahl method [Copyright &y& Elsevier]

A novel moving redox reaction boundary (MRRB) model was developed for studying electrophoretic behaviors of analytes involving redox reaction on the principle of moving reaction boundary (MRB). Traditional potassium permanganate method was used to create the boundary model in agarose gel electrophoresis because of the rapid reaction rate associated with MnO4− ions and Fe2+ ions. MRB velocity equation was proposed to describe the general functional relationship between velocity of moving redox reaction boundary (VMRRB) and concentration of reactant, and can be extrapolated to similar MRB techniques. Parameters affecting the redox reaction boundary were investigated in detail. Under the selected conditions, good linear relationship between boundary movement distance and time were obtained. The potential application of MRRB in electromigration redox reaction titration was performed in two different concentration levels. The precision of the VMRRB was studied and the relative standard deviations were below 8.1%, illustrating the good repeatability achieved in this experiment. The proposed MRRB model enriches the MRB theory and also provides a feasible realization of manual control of redox reaction process in electrophoretic analysis. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, a novel mathematical model of stump-like peak was constructed for alternative computer simulation of capillary zone electrophoresis (CZE) by using Haarhoff–Van der Linde (HVL) function. Unlike a classical model of Gaussian peak, the developed model contains both Gaussian and plateau concentration distributions of analytes. Based on the model, the relevant computer software was developed and implemented in Borland Delphi 7 environment. The relevant results revealed that (i) the software could freely simulate the plateau and Gaussian distribution peaks; (ii) the simulator could simulate a dynamic process of CZE properly; and (iii) the program could display the final electropherogram of numerous analytes in CZE. We further conducted the relevant experiments and compared them with the simulations. The comparisons demonstrated the high agreement between the simulation results and the experiments as well as those cited from references. In addition, the software could calculate effective mobility, diffusion coefficient and concentration of analytes based on the physico-chemical parameters input by users. The developed model and software have evident significance for understanding of electrophoretic separation, conditional optimization and basic computation on physico-chemical parameters of analytes in CZE. [Copyright &y& Elsevier]

Abstract: In this paper, a mathematical model and computer simulator were developed for offline sample pretreatment of heavy metal ion based on moving precipitate boundary (MPB) electrophoresis. The simulation indicates that (i) the program can easily accomplish numerical computations, such as the velocities of MPB and elution boundary (EB), and enrichment factor (EF) etc; (ii) the simulator can vividly imitate the dynamics of MPB, EB, precipitate zone, and precipitate-elution; and (iii) the software may simply optimized experimental conditions via the influence factors (e.g., voltage, hydroxyl, hydrogen and metal ions) on the EF. As a proof of concept, copper ion and its precipitate with definite blue color were, respectively chosen as mode heavy metal ion and alkaline precipitate for the relevant experiments of MPB-based sample preconcentration of heavy metal ion in large tube. All of the experimental results manifest the validity of developed mathematical model and the relevant simulation results. The model and simulator advanced herein are of clear significance to the optimization of experimental conditions and understanding of offline MPB- based sample condensation of heavy metal ion. [Copyright &y& Elsevier]

Abstract: Protein recovery from gel electrophoresis plays an important role in functional genomics and proteomics but faces a series of issues (e.g., complex procedure, low recovery, long experimental time). In this study, a monolithic column electroelution (MCE) was developed for protein recovery from gel electrophoresis. With the model proteins of bovine serum albumin (BSA), hemoglobin (Hb), and myoglobin (Mb), the developed device and method were compared with common electroelution procedures in agarose gel electrophoresis (AGE). The comparative experiments revealed that (i) the protein recovery achieved with the developed device was greater than 83%, much higher than the 41% to 50% achieved with the common devices; (ii) the running time to obtain 70% recovery was approximately 15min, evidently shorter than the 240min with the common devices; and (iii) the device and procedure were simple and less time-consuming as compared with those of the common devices. It was observed that the serum protein bands cut from polyacrylamide gel electrophoresis could be transferred into solution in 15 to 30min with 82% yield. The device, along with its relevant procedure, has potential use in protein extraction and proteomics as well as in DNA studies. [Copyright &y& Elsevier]

In China, some forensic cases are caused by barbiturates. Thus, the determination of trace level barbiturates in body fluid is important for the poisoning investigation. In this study, an online large-volume sample stacking (LVSS) with polarity switching in capillary electrophoresis (CE) was applied for the sensitive determination of barbiturates. This technique involves injecting a large volume of sample into a capillary and removing the sample matrix plug out of the capillary by reversing the polarity. Quantitation limit obtained was 0.048, 0.057, 0.039, and 0.015 μg/mL for secobarbital, amobarbital, barbital, and phenobarbital (signal-to-noise ratio = 9). By using LVSS, the stacking was simply achieved at 171.7-, 169.7-, 202.7-, and 169.1-fold for the above four barbiturates. The relative standard deviation values of intraday and interday were <2.11% and 4.69%, respectively. Recoveries were ranged from 83.7 to 105.2%. Finally, the trace analysis method was applied to the analysis of real forensic specimens and has achieved satisfactory results. [ABSTRACT FROM AUTHOR]

A concise and efficient route to new and interesting heterohelicene-like molecules has been developed through the one-pot, cascade reductive coupling reaction of o-hydroxydiimines or o-nitrodiimines and triphosgene in the presence of TiCl4/Sm. Purification of the final products only required a single recrystallization leading to high purity. High diastereoselectivity was also achieved, and two structures of the final products were confirmed by X-ray diffraction analysis. [ABSTRACT FROM AUTHOR]

Based on field and laboratory tests, physical and mechanical properties of 320 surface sediments and 12 gravity cores collected from the Zhejiang-Fujian coastal area were analyzed. The results showed that the fine-grained soil in this area was mainly composed of mud and muddy clay, with a small amount of clayey silt, silty clay and clay. They were generally characterized by high water content, high void ratio, high compressibility, high plasticity, and low shear strength. Furthermore, the factors that caused the poor physical and mechanical properties of the fine-grained soil have been analyzed for microscopic aspects (grain size distribution, mineral component, chemical composition, microstructure and macroscopic aspects (sediment source and hydrodynamic environment). The analytical results revealed that those microscopic and macroscopic factors had important relationships with the physical and mechanical properties of soil. If we can better understand those affecting factors in the forming process of the sediments, it would be beneficial for us in the study of their physical and mechanical properties. [ABSTRACT FROM AUTHOR]

SACE_7040 is presumed to be a member of the TetR family of transcriptional regulators in Saccharopolyspora erythraea, but its biological function is unknown. It was shown that the SACE_7040 gene knockout mutant formed aerial mycelium earlier than its original strain, and this phenotype could be restored by complementation of a single copy of SACE_7040 gene, demonstrating that SACE_7040 is an important regulator of the morphological differentiation of Sac. erythraea. When SACE_7040 gene was disrupted in the bldD mutant, we intriguingly found that the defect in aerial development exhibited by the bldD mutant could be overcome, suggesting a crosstalk between SACE_7040 and BldD in Sac. erythraea morphogenesis. These findings provide novel insights toward the Sac. erythraea developmental biology. [ABSTRACT FROM AUTHOR]

Abstract: We have suggested recently that ATM-Rad3-Related (ATR) DNA damage signaling pathway, which responds to single-strand breaks in DNA, was activated in response to HBV infection. ATR knockdown cells showed decreased HBV DNA yields, implying HBV infection and replication activate and exploit the activated DNA damage response. Host cell proteins may constitute an attractive target for anti-HBV-1 therapeutics, since development of drug resistance against compounds targeting these cellular cofactor proteins is unlikely. In this study, we show that one of the clinically used compounds of ATR and ataxia telangiectasia-mutated (ATM) kinases inhibitor, theophylline (Tp), significantly reduced the yield of HBV DNA, HBsAg and HBeAg in HepG2215 cell culture system, furthermore, Tp could also suppress serum HBV DNA and HBsAg levels in the HBV-transgenic mice. Consistent with this result, immunohistology also showed reduced intensity of HBsAg staining on livers from Tp-treatment group. Taken together, these data indicated the feasibility of therapeutic approaches that target host cell proteins by inhibiting a cellular gene that was required for HBV replication and provided a potential approach for the prevention and treatment of HBV infection. [ABSTRACT FROM AUTHOR]

Abstract: Ganoderic acids (GAs) were bioactive secondary metabolites produced by a traditional mushroom Ganoderma lucidum. We describe a simple and efficient method for the separation and quantitative determination of four GAs, namely Ganoderic acid T (GA-T), Ganoderic acid Mk (GA-Mk), Ganoderic acid Me (GA-Me) and Ganoderic acid S (GA-S) from dried triterpene-enriched extracts of G. lucidum mycelia powder by capillary zone electrophoresis (CZE). Under the optimum conditions, the four GAs reached the baseline separation in 9min with Glycyrrhetinic acid (GTA) as internal standard. The four GAs and internal standard (GTA) were detected at a wavelength 245nm. All calibration curves showed good linearity (r 2 >0.9958) within test ranges. Limit of detection (LOD) and limit of quantification (LOQ) were less than 0.6 and 1.8μg/mL, respectively. The relative standard deviation (R.S.D.) values of precision and recoveries were less than 5% and recoveries ranged from 91.4% to 103.6%. This was the first report on simultaneous determination of the four GAs and the results provided a firm basis for the trace analysis of GAs in dried fermentation mycelia powder of G. lucidum with high accuracy. [ABSTRACT FROM AUTHOR]