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In recent years, nitrogen vacancy (NV) centers have shown great potential for application in quantum sensor research due to their high sensitivity to magnetic fields and excellent spatial resolution. However, in practical applications, it is necessary to eliminate environmental requirements and bulky instruments brought by the optical detection of magnetic resonance (ODMR) measurement method.. In this paper, we propose an efficient portable magnetometer with a miniature confocal system (CSPM) to resist background noise and improve integration. The confocal system can automatically focus, and the volume is limited to 11 cm3. Moreover, a fiber optic flange, an antenna and a homemade integrated photodetector are integrated in the magnetometer to achieve the actual sensitivity of sub-40 nT/Hz1/2. In the experimental process of optimizing system parameters, we discovered the important influence of beam focusing or microwave uniform operation on the detection signal and proposed specific optimization methods, which have guiding significance for future integrated design. Through comparative experiments with an integration scheme that does not use uniform operation, we found that the CSPM reduces the system noise by 4.2 times and that the signal-to-noise ratio (SNR) increases by 6.2 dB.

To identify large fluctuations of parameters in the process of gasification, a control chart pattern recognition method based on optimized radial basis function neural network (RBFNN) is proposed in this paper to conduct pattern recognition of the parameters of gasification process. The proposed method is described in four aspects, feature description, feature extraction, classifier and algorithm learning and training. The initial data is described from shape features and statistical features to reduce the dimension of the data. The optimal characteristic set is selected by the association rule mining algorithm to reduce the complexity of the model. The performance of neural network is affected by the learning method. With RBFNN as a classifier, a learning method based on Bees algorithm is therefore put forward and then training recognition is compared between the proposed method and the traditional method. The results show that the proposed method has higher recognition rate and simpler structure than the traditional method, and it is very effective in monitoring and identifying abnormal fluctuations of gasification process parameters.

BaF2 crystal is well known for its short fluorescent decay time for its fast component. In measuring the time profile of $\gamma $ -ray flux density, it is important to suppress the contribution from the slow component in the BaF2 crystal. A multiple reflection and multiple-path (MRMP) short-wavelength pass filter is manufactured to achieve this goal, which can filter the slow component by wavelength selection. To accurately investigate the time profile of the fast component in the BaF2 crystal, $\gamma $ -ray source is used. The experimental results show that this filter reduces the slow scintillation light emitted from the BaF2 crystal by 99.7% with a detection efficiency of $\approx 0.11$ electrons/ $\gamma $ for the fast component. The rise time, full-width at half-maximum (FWHM), and duration time for the fast component in a BaF2 detector are 0.31, 1.12, and 2.92 ns, respectively. The fast fluorescent component of the BaF2 crystal is short enough for subnanosecond pulse radiation detection.

This study is focused on robust modeling, analysis and optimization of entrained flow co-gasification of petcoke with coal, which is very important to the stable operation of this process as well as downstream processes. Unlike general robust modeling method that traditional Taguchi's crossed array design is applied, combined array design was used in this study. Then based on the exiting general experiments and the constructed robust models, a systematic investigation was conducted into the effects exerted by oxygen and steam concentrations (OC and SC) not only on the mean but also on the variance of H2, CO and (H2 + CO) production. Finally, the co-gasification process was robustly optimized. The result reveals that the average production of H2, as well as that of (H2 + CO), rises with OC increasing but declines with SC increasing. Moreover, higher OC inhibits the fluctuations in H2 and (H2 + CO) production, while higher SC makes their fluctuations more notable. The robust optimization solutions of OC and SC are observed to be 1.56% and 50%, respectively.

Objectives To investigate the relationship between coronary artery calcification and calcium deposition in cardiomyocytes. Methods Patients who underwent valve replacement plus surgical ablation for atrial fibrillation, together with left atrial appendage resection, were included. Coronary artery calcification (CAC) score was evaluated prior to surgery using dual-source computed tomography. Samples of left atrial appendage tissue were collected to analyse the following indicators: calcium deposition, alkaline phosphatase activity, calcium content, protein levels of runt-related transcription factor 2 (Runx2), osteopontin and β-catenin, and mRNA levels of osteopontin, endothelin and ghrelin. Relationships between CAC score and various indicators were analysed by univariate logistic or linear regression. Results Out of tissue from eight patients, CAC score was not correlated with cardiomyocyte calcification (odds ratio [OR] 0.984 and OR 0.983; von Kossa or alizarin red staining, respectively). CAC score showed an inverse linear correlation with Runx2 protein (β = –0.75), but was not correlated with osteopontin (β = –0.52) or β-catenin protein (β = –0.56), mRNA levels of osteopontin, endothelin and ghrelin (β = 0.13, 0.02, and 0.02, respectively), alkaline phosphatase activity (β = 0.56), or calcium content (β = –0.22). Conclusions Coronary artery calcification was not correlated with calcium deposition in cardiomyocytes.

In the context of global warming and rising sea levels, as urbanization continues to increase, the risk situation of urban systems facing floods has become more severe. Therefore, we constructed a vulnerability assessment model for urban flood disasters in Jiangsu Province, focusing on using GIS technology to classify the land use of each city in Jiangsu Province for supervised learning. We also established a flood disaster vulnerability model to evaluate the Vulnerability of 13 cities in Jiangsu Province. Evaluation and analysis of the changes in land use vulnerability use flood disasters in Jiangsu Province from 2000 to 2020. The results show that from 2000 to 2020, the Vulnerability to flooding disasters is on the rise as a whole. Yancheng has the lowest average Vulnerability to flooding disasters due to the low population density and high greening rate in the built-up area. On the other hand, Nantong City has the most heightened average flood vulnerability due to excessive population density. The low greening rate in built-up areas has led to a worsening of flood vulnerability. Suggestions have been made to reduce the Vulnerability of urban floods in Jiangsu Province, such as vigorously developing the local economy, reasonably adjusting the rate of urbanization, and building drainage infrastructure.

The capsid protein purity of adeno-associated virus (AAV) is considered a critical quality attribute of AAV-based gene therapy products. However, the analytical methods currently available to monitor the viral capsid proteins, which are present in extremely low concentrations, have limited sensitivity and robustness, thus limiting their general applicability. As a result, there is an urgent need to develop robust separation methods with highly sensitive detection. In this article, we describe the first denaturation and fluorescence labeling procedure for AAV capsid proteins using the pyrylium dye Chromeo™ P503, enabling the establishment of the first capillary electrophoresis-sodium dodecyl sulfate (CE-SDS) method combined with laser-induced fluorescence (LIF) detection for AAV. Upon optimization using a quality-by-design approach, the newly developed method features a simple and robust one-step sample preparation workflow resulting in consistently labeled and denatured viral protein samples, which can subsequently be separated and quantified by CE-LIF. The method has been validated to be accurate and precise with a linear range of 50-150% of the nominal concentration of 2.0 × 10

Aim: This study sought to investigate the relationship between galectin-3 (Gal-3), myocardial fibrosis (MF) and outcomes in acute heart failure. Materials & methods: The single-nucleotide polymorphisms (SNPs) of LGALS3 at rs4644 and rs4652, plasma Gal-3 level, MF and major adverse events (MAEs) were obtained. Results: There was no significant difference in MAEs when categorizing patients by the LGALS3 SNPs at rs4644 and rs4652. The circulating Gal-3 was related to the degree of MF (p < 0.001). Plasma Gal-3 level and MF can predict an increased risk of MAEs (p < 0.001, p = 0.023, respectively). Conclusion: Not the SNPs of LGALS3 but Gal-3 and MF can predict MAEs in acute heart failure at 1 year of follow-up.

Objective This study was performed to assess the prevalence of nonalcoholic fatty liver (NAFL) in patients with symptomatic congestive heart failure (CHF) and compare the clinical features with those of patients without NAFL. Methods In total, 102 patients with CHF were divided into NAFL and non-NAFL groups according to their hepatic ultrasonography findings. All patients underwent transthoracic echocardiography and cardiac magnetic resonance examination. Follow-up was performed for major cardiovascular events (MACE) and readmission due to heart failure at 1, 3, 6, and 12 months after the index hospitalization. Results NAFL was detected in 37 of 102 patients (36.27%). Compared with the non-NAFL group, patients with NAFL were younger, had a higher body mass index and left ventricular (LV) mass index, and had more severe fibrosis. MACE and readmission occurred in 15 patients in the NAFL group and 29 patients in the non-NAFL group, without a significant difference. Linear regression analysis revealed that after adjusting for confounders, NAFL was independently associated with the LV fibrosis size and the ratio of the LV fibrosis size to the LV mass index. Conclusions NAFL is present in more than one-third of patients with CHF and is associated with the severity of LV fibrosis.

Due to the parameters’ complex variation in gasification process, traditional monitoring method detecting the observed data directly may case missing alarm. This paper proposed a real-time identification model with high accuracy using Kalman filter and control chart jointly. The observed data is divided into state value and deviation value using Kalman filter, then they are separately monitored by control char. Simulation experiments on gasifier temperature monitoring in three typical fluctuation modes and field application on H2 and CO monitoring for a gasifier under there different starting condition were carried out. The proposed method respectively identified 4, 6 and 2 alarms in simulation experiments, and identified 10, 3, 12, 68, 2 and 4 alarms in filed application. Besides, the proposed method also accurately identified the presented the preset sinusoidal fluctuations and upward shift when monitoring temperature and 4 systematic variations and 23 special variations when monitoring H2 and CO. The performance of the proposed method is significantly more accuracy than that of traditional methods. So the integrated application of control chart and Kalman filter in gasification process parameter monitoring has the advantages of high sensitivity of outlier alarm, high identification of variation and high applicability of multimode fluctuations under various conditions.

In this Letter, we propose an integrated two-dimensional magnetometer module based on nitrogen vacancy centers in diamond. The sensor has a constructed area of 7.12 cm2 and exhibits a magnetic-field sensitivity of approximately 25.12 nT/Hz1/2. By placing anti-microwave shield nets optimizing interference distance, the integrated scheme eliminates the effects of microwave interference on the amplifier. We propose the fixed-frequency optical detection of magnetic resonance, which is used to measure the relation between the magnetic field and the photoluminescence by scanning the magnetic field. Without relying on the lock-in technique, we developed an algorithm for analyzing the magnetic noise based on the PL noise analysis.

In the entrained flow coal gasification process, the gas production is critically affected by the operating temperature (OT) and coal ash melting point (AMP), and the AMP is one of key factors for the determinations of OT. Considering the fact that coal is a typical nonhomogeneous substance and the coal ash composition varies from batch to batch, this paper proposes the application of the Markov Chain (MC) method in simulation of the random AMP series and the stochastic optimization of OT based on MC simulation for entrained flow coal gasification. The purpose of this paper is to provide a more accurate optimal OT decision method for entrained flow coal gasification practice. In this paper, the AMP was regarded as a random variable, and the random process method, Markov Chain, was used to describe the random AMP series of feed coal. Firstly, the MC simulation model about AMP was founded according to an actual sample data, 200 sets of AMP data from an industrial gasification plant under three simulation schemes (the sample data were individually divided into 16, eight and four state groups,). The comparisons between the simulation results and the actual values show that the founded MC simulation model descries the AMP series very well. Then, a stochastic programming model based on MC simulation for OT optimization was developed. Finally, this stochastic programming optimization model was optimized by genetic algorithm (GA). Comparing with the conventional OT optimization method, the proposed stochastic OT optimization model integrated MC simulation can ascertain a more accurate OT for guiding the coal gasification practice.

Oxidative stress (OS) has been thought to play a main role in the etiopathogenesis of recurrent aphthous stomatitis (RAS), which is one of the most common oral mucosal diseases characterized by recurrent and painful oral ulcers. The aim of this investigation was to evaluate the enzymatic antioxidants status in patients with RAS in the active stage and remission stage.Ninety-seven patients with idiopathic minor RAS and 102 race-, age- and gender-matched healthy individuals were recruited. All these subjects were allocated to three groups: RAS patients with active lesion (group A); the same patients in group A in the remission stage of RAS (group B); and healthy individuals without RAS (group C). Following an overnight fast, blood samples were obtained. The serum levels of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSHPx) were measured by the spectrophotometric method. Independent-samples t-test and paired t-test were performed for statistical evaluation.The serum levels of SOD, GSHPx, and CAT (83.9 ± 17.1 U/ml, 6687.2 ± 2629.2 U/ml, 1789.7 ± 593.8 U/l) were found to be significantly lower in group A as compared to those of group B (99.8 ± 11.1 U/ml, 9364.1 ± 1607.9 U/ml, 2789.1 ± 1113.4 U/l; P0.05) or group C (97.3 ± 12.1 U/ml, 9246.2 ± 2376.1 U/ml, 2819.0 ± 914.8 U/l; P0.05). No significant differences were found between group B and group C with respect to any one of these enzymatic antioxidants (P0.05).Our results indicate that enzymatic antioxidant defense system is impaired in RAS patients with active lesion and seems to play a crucial role in its pathogenesis.

Background: Recurrent aphthous stomatitis (RAS) is one of the most common inflammatory ulcerative conditions of oral cavity with uncertain etiology. Several studies have reported that oxidative stress may be associated with RAS. The aim of this study was to compare the serum levels of total antioxidant status (TAS), nitric oxide (NO) and nitric oxide synthase (NOS) in minor RAS (MiRAS) patients with healthy individuals and determine the possible association of MiRAS with the 3 physiological parameters mentioned above. Methods: Ninety patients with idiopathic MiRAS and 90 race-, age- and sex-matched healthy individuals were included in this study. All these subjects were allocated to 3 groups: MiRAS patients in the active stage (Group A); the same MiRAS patients in Group A in the inactive stage (Group B); healthy individuals without MiRAS (Group C). Serum levels of TAS, NO and NOS were determined by the spectrophotometric method. Independent sample t test and paired t test were performed for statistical evaluation. Results: Serum TAS level of Group A was significantly decreased than that of Group C, whereas the serum level of NO was significantly higher in Group A as compared to Group C (P .05). Conclusions: MiRAS is associated with decreased TAS and increased NO levels, but NOS may not play an important role in the aetiopathogenesis.

Decapod crustaceans are important animal models for neurobiologists due to their relatively simple nervous systems with well-defined neural circuits and extensive neuromodulation by a diverse set of signaling peptides. However, biochemical characterization of these endogenous neuropeptides is often challenging due to limited sequence information about these neuropeptide genes and the encoded preprohormones. By taking advantage of sequence homology in neuropeptides observed in related species using a home-built crustacean neuropeptide database, we developed a semi-automated sequencing strategy to characterize the neuropeptidome of Panulirus interruptus, an important aquaculture species, with few known neuropeptide preprohormone sequences. Our streamlined process searched the high mass accuracy and high-resolution data acquired on a LTQ-Orbitrap with a flexible algorithm in ProSight that allows for sequence discrepancy from reported sequences in our database, resulting in the detection of 32 neuropeptides, including 19 novel ones. We further improved the overall coverage to 51 neuropeptides with our multidimensional platform that employed multiple analytical techniques including dimethylation-assisted fragmentation, de novo sequencing using nanoliquid chromatog raphy-electrospray ionization-quadrupole-time-of-flight (nanoLC–ESI–Q-TOF), direct tissue analysis, and mass spectrometry imaging on matrix-assisted laser desorption/ionization (MALDI)-TOF/TOF. The high discovery rate from this unsequenced model organism demonstrated the utility of our neuropeptide discovery pipeline and highlighted the advantage of utilizing multiple sequencing strategies. Collectively, our study expands the catalog of crustacean neuropeptides and more importantly presents an approach that can be adapted to exploring neuropeptidome from species that possess limited sequence information.

Mass spectrometry (MS) coupled to sample preparation and separation techniques has become a primary tool for proteomics studies. However, due to sample complexity, it is often challenging to achieve fast and efficient sample preparation prior to MS analysis. In recent decades, monolithic materials have been developed not only as chromatographic media, but also as efficient solid supports for immobilizing multiple types of affinity reagents. Herein, the N-acryloxysuccinimide-co-acrylamide-co-N,N'-methylenebisacrylamide (NAS-AAm-Bis) monolith was fabricated within silanized 200 μm i.d. fused-silica capillaries and was used as an immobilized enzyme reactor (IMER). The column was conjugated with trypsin/Lys-C and Lys-N enzymes to allow enzymatic digestions to occur while protein mixture was loaded onto the IMER column followed by MS-based proteomics analysis. Similar MS signal and protein sequence coverage were observed using protein standard bovine serum albumin (BSA) compared to in-solution digestion. Furthermore, mouse serum, yeast, and human cell lysate samples were also subjected to enzymatic digestion by both IMER (in seconds to minutes) and conventional in solution digestion (overnight) for comparison in large-scale proteomics studies. Comparable protein identification results obtained by the two methods highlighted the potential of employing NAS-based IMER column for fast and highly efficient sample preparation for MS analysis in proteomics studies.

Effect of TiO 2 -SiO 2 -SnO x sol-gel coating burnt at 300 °C on the cpTi-porcelain bond strength was investigated in this study. Before the porcelain was fused, the phase, surface morphology, and static water contact angle of the intermediate layer were evaluated. The cpTi-porcelain bond strength was measured using the three-point flexure test according to ISO 9693 standard. The surface morphology of titanium surface debonded from porcelain was evaluated with a scanning electron microscope. Statistical analysis was made with an independent samples t test. No rutile phase was found in the tested specimen coated with TiO 2 -SiO 2 -SnO x sol-gel coating. The cpTi-porcelain bond strength of coated group (35.7±2.65 MPa) was significantly higher than that of noncoated group (31.7±3.52 MPa). Statistical difference of static water contact angle was found between the two groups. The surface morphology of the intermediate layer was compact and homogeneous with visible cracks. Sn element was found in the titanium surface after the porcelain was debonded, which indicated that the fracture mode of titanium-porcelain system might have been changed. The results show that the TiO 2 -SiO 2 -SnO x sol-gel coating burnt at 300 °C can improve the bond strength of titanium to porcelain.

ZnO-based scintillators are particularly well suited for use as ultrafast pulsed radiation detectors which have shown broad application prospects in various fields such as the inertial confinement fusion (ICF) diagnosis, the nuclear reaction mechanism, etc. Using the hydro-thermal method, a ZnO single-crystal doped with Scandium (ZnO:Sc) sample was prepared. As a new ZnO-based scintillator, the scintillation characteristics of ZnO:Sc have not been reported previously. In this paper, optical and scintillation characteristics of ZnO:Sc single-crystal were studied. Also a scintillation detector based on ZnO:Sc was designed. Excited by the alpha-particle, the rise time of ZnO:Sc detectors was from 162.5 to 170.7 ps, and the fall time was from 300.4 to 328.8 ps.

Coupling CE-based separation techniques to MS creates a powerful platform for analysis of a wide range of biomolecules from complex samples because it combines the high separation efficiency of CE and the sensitivity and selectivity of MS detection. ESI and MALDI, as the most common soft ionization techniques employed for CE and MS coupling, offer distinct advantages for biomolecular characterization. This review is focused primarily on technological advances in combining CE and chip-based CE with ESI and MALDI-MS detection in the past five years. Selected applications in the analyses of metabolites, peptides, and proteins with recently developed CE-MS platforms are also highlighted.

A semi-automated analytical platform featuring the coupling of monolithic reversed-phase liquid chromatography (RPLC) to matrix-assisted laser desorption/ionization mass spectrometric imaging (MALDI MSI) has been developed and evaluated. This is the first time that LC separation is readily coupled to MS imaging detection for the analysis of complex peptide mixtures both qualitatively and quantitatively. Methacrylate-based monolithic column with C12 functional groups is fabricated for fast RPLC separation. The LC flow and matrix flow are collected on a commercially available MALDI plate which is mechanically controlled and analyzed with MALDI MSI subsequently. Both tryptic peptides digested from bovine serum albumin (BSA) and endogenous neuropeptides extracted from the blue crab Callinectes sapidus are analyzed with this novel LC-MSI platform. Compared with regular offline LC fractionation coupled with MALDI MS detection, LC-MSI exhibits significantly increased MS signal intensity due to retaining of temporal resolution from separation dimension via continuous sampling, which results in increased number of peptides detected and accurate quantitation. In addition, imaging signals enable improved data analysis based on either mass-to-charge ratio or retention time, which is extremely beneficial for the analysis of complex analytes. These findings have demonstrated the potential of employing LC-MSI platform for enhanced proteomics and peptidomics studies.

Herein we report the first attempt of coupling multidimensional separations to matrix-assisted laser desorption/ionization (MALDI) mass spectrometric imaging detection. Complex neuropeptide mixtures extracted from crustaceans were first fractionated by reversed-phase liquid chromatography (RPLC), and then subjected to a capillary electrophoresis-mass spectrometric imaging platform. With a specific focus on orcokinin family neuropeptides, we demonstrated that these trace-level analytes from complex neural tissue samples can be fully separated from chemical noise and interfering components and visualized as mass spectrometric imaging signals. A total of 19 putative orcokinins were detected, with highly efficient separations within the family being achieved for the first time. The results indicate that two-dimensional separation coupling to mass spectrometric imaging can serve as a novel and powerful tool in proteomics and peptidomics studies.

Herein, we report an immobilized pH gradient (IPG) capillary isoelectric focusing-matrix-assisted laser desorption/ionization mass spectrometry (CIEF-MALDI MS) platform designed for the separation of complex neuropeptides. This platform features a poly(glycidyl methacrylate-divinylbenzene) (GMA-DVB)-based monolithic column for CIEF separation. Different from regular CIEF, carrier ampholytes are preimmobilized on the monolithic surface instead of being added to the sample. An off-line coupling of IPG-CIEF to MALDI MS has been established. Comparison with regular CIEF and optimizations are performed with bovine serum albumin tryptic peptides and extracted neuropeptide mixtures from crustacean Callinectes sapidus. It has been demonstrated that the separation of complex peptide mixtures in neutral and basic pH ranges can be achieved in less than 10 min with comparable separation efficiency with regular CIEF, while the MS signal is significantly enhanced when employing IPG-CIEF. Enhanced neuropeptide detection is also observed after coupling IPG-CIEF with MALDI MS.

Herein we report a highly efficient and reliable membrane-assisted capillary isoelectric focusing (MA-CIEF) system being coupled with MALDI-FTMS for the analysis of complex neuropeptide mixtures. The new interface consists of two membrane-coated joints made near each end of the capillary for applying high voltage, while the capillary ends were placed in the two reservoirs which were filled with anolyte (acid) and catholyte (base) to provide pH difference. Optimizations of CIEF conditions and comparison with conventional CIEF were carried out by using bovine serum albumin (BSA) tryptic peptides. It was shown that the MA-CIEF could provide more efficient, reliable and faster separation with improved sequence coverage when coupled to MALDI-FTMS. Analyses of orcokinin family neuropeptides from crabs Cancer borealis and Callinectes sapidus brain extracts have been conducted using the established MA-CIEF/MALDI-FTMS platform. Increased number of neuropeptides was observed with significantly enhanced MS signal in comparison with direct analysis by MALDI FTMS. The results highlighted the potential of MA-CIEF as an efficient fractionation tool for coupling to MALDI MS for neuropeptide analysis.

The effects of TiO 2 –SiO 2 sol–gel coating with different firing temperatures (300 °C, 500 °C, and 750 °C) on the cpTi–porcelain bond strength were investigated in the present study. Prior to applying the low-fusing dental titanium porcelain, the phase, surface morphology, surface roughness and static water contact angle of the intermediate layer were evaluated. The cpTi–porcelain bond strength was measured using the three-point flexure test according to ISO 9693 standard. Statistical analyses were made using one-way ANOVA and Dunnett- t test. Significantly higher bond strength of TiO 2 –SiO 2 /750 °C (specimens coated with TiO 2 –SiO 2 sol–gel coating and fired at 750 °C for 1 h) when compared to the control group was observed ( p 2 –SiO 2 sol–gel coating. The surface morphology of the intermediate layer was apparently different with different firing temperatures. It was found that the static water contact angle of TiO 2 –SiO 2 /750 °C significantly decreased ( p a of TiO 2 –SiO 2 /500 °C and TiO 2 –SiO 2 /750 °C in comparison to that of the control group was observed ( p > 0.05). The results show that the TiO 2 –SiO 2 sol–gel coating fired at 750 °C for 1 h can notably improve the cpTi–porcelain bond strength and may be suitable for clinical use.

Herein we describe a sensitive and straightforward off-line capillary electrophoresis (CE) matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) interface in conjunction with stable isotopic labeling (SIL) technique for comparative neuropeptidomic analysis in crustacean model organisms. Two SIL schemes, including a binary H/D formaldehyde labeling technique and novel, laboratory-developed multiplexed dimethylated leucine-based isobaric tagging reagents, have been evaluated in these proof-of-concept experiments. We employ these isotopic labeling techniques in conjunction with CE-MALDI-MS for quantitative peptidomic analyses of the pericardial organs isolated from two crustacean species, the European green crab Carcinus maenas and the blue crab Callinectes sapidus. Isotopically labeled peptide pairs are found to co-migrate in CE fractions and quantitative changes in relative abundances of peptide pairs are obtained by comparing peak intensities of respective peptide pairs. Several neuropeptide families exhibit changes in response to salinity stress, suggesting potential physiological functions of these signaling peptides.

Guan Xin II decoction (GX II) is a widely used traditional Chinese medicine (TCM) formula for the treatment of coronary heart diseases. However, the comprehensive chemical analysis of the formulated GX II is not clarified yet. An HPLC-DAD-ESI-MS n method was established to analyze GX II and its five component herbs, respectively. A total of 57 compounds, including phenolic acids, glycosides, flavonoids, and alkaloids were identified or tentatively characterized on the basis of their mass spectra or by comparison with reference standards. This is the first time that the chemical composition of GX II was elucidated by LC/MS. The established method will be used for quality control and pharmacokinetic studies of GX II. GX II:Guan Xin II, Guan Xin Er Hao (in Chinese) TCM:traditional Chinese medicine

A liquid chromatography-diode array detection-electrospray ionization ion trap mass spectrometry (LC-DAD-ESI-MS(n)) method was established for the analysis of danshensu, caffeic acid, ferulic acid and isoferulic acid in rat plasma, bile, urine and feces after oral administration or intravenous injection. Liquid-liquid extraction was employed for the preparation of biosamples, and the chromatographic separation was carried out using an Agilent Zorbax Extend C(18) reversed phase column and acetonitrile-0.1% formic acid as the mobile phase. Totally nineteen metabolites were detected and identified as prototype, methylated, hydroxylated, sulfated and glucuronized conjugates. The metabolism of the individual phenolic acids in biosamples was investigated, and the metabolic pathway was proposed. By comparing the metabolism of different compounds which shared similar structures, we were able to find that methylation was the main pathway of danshensu metabolism, and the double bond on the side chain was critical for the drug excretion via bile and the formation of glucuronized conjugates. The results proved that the established method was simple, sensitive and reliable, which could be used to detect and identify the structures of metabolites and to better understand their in vivo metabolism.

An ICI (insulator-conductor-insulator) gamma-ray detector designed for measurement of fast rising, high intensity pulsed gamma-ray fluxes has been developed. Like vacuum Compton diode (VCD) and dielectric Compton diode (DCD) devices, the ICI detector operates by utilization of the Compton effect. It has a very fast time response (rise time is less than 1 ns), a large linearity and a wide dynamic range. It is designed to measure intense and rapidly changing gamma-ray fluxes in highly mixed neutron-gamma radiation fields. Its sensitivity to 1.25 MeV gamma rays is about 1.8 x 10-20, for the 50 mm collimation diameter, which is relatively high compared with VCD and DCD devices. The simulated gamma-ray sensitivity agrees well with the experimental value. The gamma-to-neutron sensitivity ratio is about three orders of magnitudes for neutron energies below 14.1 MeV and 1.25 MeV gamma rays. Compared to existing VCD and DCD devices, the ICI detector requires no vacuum and power supply in operation, and also minimally attenuates a collimated gamma-ray beam due to its overall thickness of 3 mm in beam path.

To evaluate the influence of TiO(2)-SiO(2)-SnOx nano-coatings with different firing temperatures on the bond strength of low-fusing dental porcelain to pure titanium.The surface of pure titanium was coated uniformly with TiO(2)-SiO(2)-SnOx nano-coatings by solution-gelatin (Sol-Gel) technology and then fired at 300 °C (group A) or 750 °C (group B) for 1 h. The specimens without any coatings were the control group (group C). There were 10 specimens in each group. Dental porcelain was sintered on the surface of titanium specimens. Surface roughness and contact angle of the coatings were also detected. The titanium-porcelain bond strength was investigated according to YY 0621-2008 standards using three-point flexure bond test. The phase composition of the TiO(2)-SiO(2)-SnOx nano-coatings was characterized by X-ray diffraction(XRD). The interface of titanium-porcelain and TiO(2)-SiO(2)-SnOx nano-coatings were observed using scanning electron microscope (SEM).No rutile phase was found in these specimens of group A and group B. The surface roughness of group A, B, C was (0.97 ± 0.06), (0.99 ± 0.03), (0.96 ± 0.07) µm, respectively. No significant difference was found among the three groups. Compared with that of group C (64.37° ± 3.01°), contact angles detected in group A (52.04° ± 3.15°) and group B (85.27° ± 4.17°) were significantly different (P0.05). The bond strength of titanium-porcelain in group A [(35.66 ± 2.65) MPa] was significantly increased compared with those in group B [(26.18 ± 2.22) MPa] and group C [(31.66 ± 3.52) MPa]. SEM photomicrographs of titanium-porcelain interface morphology of the specimens before porcelain sintering showed that TiO(2)-SiO(2)-SnOx nano-coatings in group A were compact and homogeneous with petty cracks and those in group B was loose and arranged disorderly.TiO(2)-SiO(2)-SnOx nano-coating fired at 300 °C is significantly effective in improving the titanium-porcelain bond strength.

Statement of problem The passive film on the surface of titanium can be destroyed by immersion in a fluoridated acidic medium. Coating with titanium nitride (TiN) may improve the corrosion resistance of titanium. Purpose The purpose of this in vitro study was to investigate the effect of duplex treatment with plasma nitriding and TiN coating on the corrosion resistance of cast titanium. Material and methods Cast titanium was treated with plasma nitriding and TiN coating. The corrosion resistance of the duplex-treated titanium in fluoride-containing artificial saliva was then investigated through electrochemical and immersion tests. The corroded surface was characterized by scanning electron microscopy (SEM) with energy-dispersive spectroscopy surface scan analysis. The data were analyzed using ANOVA (α=.05) Results Duplex treatment generated a dense and uniform TiN film with a thickness of 4.5 μm. Compared with untreated titanium, the duplex-treated titanium displayed higher corrosion potential (E corr ) values ( P .001) and lower corrosion current density (I corr ) values ( P .001). SEM results showed that the surface of untreated titanium was more heavily corroded than that of duplex-treated titanium. Surface scan analysis of duplex-treated titanium that had been immersed in artificial saliva containing 2 g/L fluoride revealed fluorine on the titanium surface, whereas fluorine was not observed on the surface of untreated titanium after immersion in fluoride-containing artificial saliva. The concentration of titanium ions released from the treated titanium was less than the amount released from untreated titanium ( P .001). Conclusions Duplex treatment by plasma nitriding and TiN coating significantly improved the corrosion resistance of cast titanium in a fluoride-containing environment.

A series of cross-linked network polysiloxanes containing oligoethylene oxide units, (OCH 2 CH 2 ) n , as internal free chains have been synthesized by performing hydrosilylation of partially PEO-substituted polysiloxane precursor with α, ω-diallyl terminated poly(ethylene glycol). The polymer electrolytes were formed by complexing with LiN(CF 3 SO 2 ) 2 electrolyte salt and exhibited superior conductive property. The σ RT of the network polymer electrolytes is in the range of 2.50×10 −5 to 1.62×10 −4 S/cm and depends on the cross-linking density (in terms of Si–H amount of the siloxane precursor), repeating unit number of internal oligoethylene oxide and chain length of the cross-linker. The significant enhancement of the conductivity was observed when low molecular weight dimethyl poly(ethylene glycol) was added as plasticizer. The temperature dependence of the ionic conductivity was also studied, following the Vogel–Tamman–Fulcher (VTF) equation.

Matrix-assisted laser desorption/ionization (MALDI) mass spectrometric imaging (MSI) has been employed as a detection method for both capillary electrophoresis (CE)-MALDI and liquid chromatography (LC)-MALDI analyses. Based on our previous studies, here we report a new interface to couple LC with MSI by employing an automated matrix sprayer. The LC trace is directly collected on a ground stainless steel MALDI plate and dried. The matrix is sprayed on the MALDI plate using a programmable matrix sprayer. With the highly uniform matrix layers produced from the sprayer, the MS image signal quality is significantly improved with enhanced signal-to-noise ratios for analyte peaks. With the programmable matrix application and imaging MS data acquisition, the new LC-MSI platform exhibits highly stable and reproducible performance. A total of 87 bovine serum albumin (BSA) tryptic peptides and 295 putative neuropeptides from blue crab pericardial organs have been observed with LC-MSI analysis, exhibiting better performance in terms of peptide coverage than regular LC-MALDI with discrete spot collection and our previously reported LC-MSI interface with the matrix being delivered by a capillary. In addition to relative quantitation with isotopic labeling as we have previously demonstrated, we performed the first absolute quantitation using the new LC-MSI platform and obtained accurate quantitation results for neuropeptides, indicating great potential for quantitative analysis of complex samples.

Barium fluoride (BaF2) is an inorganic scintillation material used for the detection of X/gamma radiation due to its relatively high density, equivalent atomic number, radiation hardness, and high luminescence. BaF2 has a potential capacity to be used in gamma ray timing experiments due to the prompt decay emission components. It is known that the light output from BaF2 has three decay components: two prompt of those at approximately 195 nm and 220 nm with a decay constant around 600-800 ps and a more intense, slow component at approximately 310 nm with a decay constant around 630 ns which hinders fast timing experiments. We report here the development of a fast radiation detector based on a BaF2 scintillation crystal employing a special optical filter device, a multiple reflection multi-path ultraviolet region short-wavelength pass light guides (MRMP-short pass filter) by using selective reflection technique, for which the intensity of the slow component is reduced to less than 1%. The methods used for this study provide a novel way to design radiation detector by utilizing scintillation crystal with several emission bands.

Herein we report a pressure-assisted capillary electrophoresis-mass spectrometric imaging (PACE-MSI) platform for peptide analysis. This new platform has addressed the sample diffusion and peak splitting problems that appeared in our previous groove design, and it enables homogenous deposition of the CE trace for high-throughput MALDI imaging. In the coupling of CE to MSI, individual peaks (m/z) can be visualized as discrete colored image regions and extracted from the MS imaging data, thus eliminating issues with peak overlapping and reducing reliance on an ultra-high mass resolution mass spectrometer. Through a PACE separation, 46 tryptic peptides from bovine serum albumin and 150 putative neuropeptides from the pericardial organs of a model organism blue crab Callinectes sapidus were detected from the MALDI MS imaging traces, enabling four to six-fold increase of peptide coverage as compared with direct MALDI MS analysis. For the first time, quantitation with high accuracy was obtained using PACE-MSI for both digested tryptic peptides and endogenous neuropeptides from complex biological samples in combination with isotopic formaldehyde labeling. Although MSI is typically employed in tissue imaging, we show in this report that, it offers a unique tool for quantitative analysis of complex trace-level analytes with CE separation. These results demonstrate a great potential of the PACE-MSI platform for enhanced quantitative proteomics and neuropeptidomics.

Herein we report the first attempt of coupling multidimensional separations to matrix-assisted laser desorption/ionization (MALDI) mass spectrometric imaging detection. Complex neuropeptide mixtures extracted from crustaceans were first fractionated by reversed-phase liquid chromatography (RPLC), and then subjected to a capillary electrophoresis-mass spectrometric imaging platform. With a specific focus on orcokinin family neuropeptides, we demonstrated that these trace-level analytes from complex neural tissue samples can be fully separated from chemical noise and interfering components and visualized as mass spectrometric imaging signals. A total of 19 putative orcokinins were detected, with highly efficient separations within the family being achieved for the first time. The results indicate that two-dimensional separation coupling to mass spectrometric imaging can serve as a novel and powerful tool in proteomics and peptidomics studies.

The crustacean sinus gland (SG) is a well-defined neuroendocrine site that produces numerous hemolymph-borne agents including the most complex class of endocrine signaling molecules-neuropeptides. Via a multifaceted mass spectrometry (MS) approach, 70 neuropeptides were identified including orcokinins, orcomyotropin, crustacean hyperglycemic hormone (CHH) precursor-related peptides (CPRPs), red pigment concentrating hormone (RPCH), pigment dispersing hormone (PDH), proctolin, RFamides, RYamides, and HL/IGSL/IYRamide. Among them, 15 novel orcokinins, 9 novel CPRPs, 1 novel orcomyotropin, 1 novel Ork/Orcomyotropin-related peptide, and 1 novel PDH were de novo sequenced via collision induced dissociation (CID) from the SG of a model organism Callinectes sapidus. Electron transfer dissociation (ETD) was used for sequencing of intact CPRPs due to their large size and higher charge state. Capillary isoelectric focusing (CIEF) was employed for separation of members of the orcokinin family, which is one of the most abundant neuropeptide families observed in the SG. Collectively, our study represents the most complete characterization of neuropeptides in the SG and provides a foundation for future investigation of the physiological function of neuropeptides in the SG of C. sapidus.

In this work, the utilization of matrix-assisted laser desorption/ionization-mass spectrometric imaging (MALDI-MSI) for capillary electrophoresis (CE) analysis of peptides based on a simple and robust off-line interface has been investigated. The interface involves sliding the CE capillary distal end within a machined groove on a MALDI sample plate, which is precoated with a thin layer of matrix for continuous sample deposition. MALDI-MSI by time of flight (TOF)/TOF along the CE track enables high-resolution and high-sensitivity detection of peptides, allowing the reconstruction of a CE electropherogram while providing accurate mass measurements and structural identification of molecules. Neuropeptide standards and their H/D isotopic formaldehyde-labeled derivatives were analyzed using this new platform. Normalized intensity ratios of individual ions extracted from the CE trace were compared to MALDI-MS direct analysis and the theoretical ratios. The CE-MALDI-MSI results show potential for sensitive and quantitative analysis of peptide mixtures spanning a wide dynamic range.

A sensitive LC/MS method was established to investigate the in vivo metabolism of GuanXin II prescription, a five-component Chinese herbal medicine formulation. Rat plasma, bile, urine, and feces were collected and analyzed following oral administration of the water decoction. A total of 50 compounds were identified, including 17 prototypes and 33 metabolites underwent methylation, oxidation, hydrolysis, sulfate conjugation, glucuronide conjugation, and glutathion conjugation. In addition, the component herb of the formulation from which the metabolites were derived was also identified. Among the five component herbs, Rhizoma Chuanxiong, Flos Carthami, and Lignum Dalbergiae Odoriferae were actively metabolized, contributing 26 metabolites and 2 prototypes, while Radix Salviae Miltiorrhizae and Radix Paeoniae Rubra underwent less biotransformation, yielding 7 metabolites and 15 prototypes. This is the first study on the metabolic profile of GuanXin II prescription. The results could be valuable to elucidate the material basis of this formulated Chinese medicine.

A systematic study on pharmacokinetics and tissue distribution of danshensu (one of the major active components from Salvia miltiorrhizae) is conducted using a rapid and sensitive high-performance liquid chromatographic (HPLC) method. Before HPLC analysis, biological samples are pretreated with a liquid-liquid extraction. Separation of danshensu and internal standard is achieved on an Agilent Zorbax C18 column with a mobile phase made up of acetonitrile and 0.05% trifluoracetic acid at a flow rate of 0.8 mL/min. The calibration curves in plasma and tissues are linear in the given concentration ranges, with r2 no less than 0.99. The intra-day and inter-day relative standard deviations in the measurement of quality control samples are less than 15%, and the accuracies are in the range of 86-115%. The recoveries of danshensu in plasma and tissues are among 80% to 118%. Meanwhile, the multi-peaks in pharmacokinetic profiles are observed. The method is successfully applied to the pharmacokinetics and tissue distribution study of danshensu after a single oral administration of 50.0 mg/kg sodium danshensu to rats.

This study was conducted to compare the in vivo metabolites of salvianolic acid B (Sal B) between normal rats and antibiotic-treated rats and to clarify the role of intestinal bacteria on the absorption, metabolism and excretion of Sal B. A valid method using LC-MS(n) analysis was established for identification of rat biliary and fecal metabolites. And isolation of normal rat urinary metabolites by repeated column chromatography was applied in this study. Four biliary metabolites and five fecal metabolites in normal rats were identified on the basis of their MS(n) fragmentation patterns. Meanwhile, two normal rat urinary metabolites were firstly identified on the basis of their NMR and MS data. In contrast, no metabolites were detected in antibiotic-treated rat urine and bile, while the prototype of Sal B was found in antibiotic-treated rat feces. The differences of in vivo metabolites between normal rats and antibiotic-treated rats were proposed for the first time. Furthermore, it was indicated that the intestinal bacteria showed an important role on the absorption, metabolism and excretion of Sal B. This investigation provided scientific evidence to infer the active principles responsible for the pharmacological effects of Sal B.

A method using liquid chromatography-electrospray ionization tandem mass spectrometry (LC-MS/MS) analysis was established for the identification of metabolites in rat after oral administration of protocatechuic aldehyde, a major bioactive phenolic acid in the roots of Salvia miltiorrhiza. Eleven metabolites in rat plasma and urine were firstly identified as protocatechuic aldehyde, protocatechuic acid and their methylated, glucuronized or glycine conjugates on the basis of their MS fragmentation behaviors, while nine of these metabolites (except protocatechuic aldehyde and protocatechuic acid) were detected in rat bile. In addition, the possible metabolic pathway was proposed for the first time. In the phase I metabolism, protocatechuic aldehyde could be oxidized to protocatechuic acid. The conjugates would be formed in rat intestine, liver and kidney and excreted from rat urine and bile. Enthrohepatic circulation played an important role in the metabolism of protocatechuic aldehyde. The results proved that the established method was simple, reliable and sensitive, revealing that it could be used to rapid screen and identify the structures of active components responsible for pharmacological effects of protocatechuic aldehyde and to better understand its in vivo metabolism.