饮料中35种添加剂的超高效液相色谱/四级杆-飞行时间质谱筛查法

目的:建立超高效液相色谱-四级杆-飞行时间质谱(ultra performance liquid chromatography coupled with quadrupole-time of flight mass spectrometry,UPLC-Q-TOF MS)快速检测饮料中35种添加剂(3种防腐剂、5种甜味剂和27种色素)的分析方法。方法:样品用乙腈-水(8∶2)提取后,采用XBridge Peptide BEH C18色谱柱(100 mm×2.1 mm,3.5μm)分离,以乙腈-0.025%甲酸水溶液(含10 mmol/L的甲酸铵)为流动相,梯度洗脱,Q-TOF MS电喷雾正、负离子模式分析检测。在全扫描采集模式下,以准分子离子峰的峰面积定量,以化合物的色谱保留时间和精确质量数定性。在Target MS/MS采集模式下,通过碎片离子的精确质量数进一步确证化合物。结果:35种添加剂在0.002~100 mg/kg范围内具有较好的线性关系,相关系数均大于0.99,其定量限为0.01~10 mg/kg,添加回收率在70.5%~110.6%范围内,相对标准偏差(RSD)均小于2.8%~11.5%(n=6)。结论:该方法简便、快速、灵敏,适用于饮料中多类添加剂的同时检测。

Auditory attention model based on Chirplet for cross-corpus speech emotion recognition

To solve the problem of mismatching features in an experimental database, which is a key technique in the field of cross-corpus speech emotion recognition, an auditory attention model based on Chirplet is proposed for feature extraction.First, in order to extract the spectra features, the auditory attention model is employed for variational emotion features detection. Then, the selective attention mechanism model is proposed to extract the salient gist features which showtheir relation to the expected performance in cross-corpus testing.Furthermore, the Chirplet time-frequency atoms are introduced to the model. By forming a complete atom database, the Chirplet can improve the spectrum feature extraction including the amount of information. Samples from multiple databases have the characteristics of multiple components. Hereby, the Chirplet expands the scale of the feature vector in the timefrequency domain. Experimental results show that, compared to the traditional feature model, the proposed feature extraction approach with the prototypical classifier has significant improvement in cross-corpus speech recognition. In addition, the proposed method has better robustness to the inconsistent sources of the training set and the testing set.

食品中多种兽药残留的同时筛查检测

建立了食品中7类兽药残留的定性筛查检测方法。样品采用QuEChERS方法进行前处理(乙腈提取,Al_2O_3吸附剂净化),采用超高效液相色谱-四级杆-飞行时间质谱仪(UPLC-Q-TOFMS)检测,以化合物的色谱保留时间和精确质量数定性,在TargetMS/MS采集模式下,通过碎片离子的精确质量数进一步确证化合物。该方法简便、快速、灵敏,适用于食品中多种兽药残留的同时定性筛查。

谷物食品中红木素和降红木素的快速筛查方法的建立

该实验建立了超高效液相色谱-四级杆-飞行时间质谱(UPLC-Q-TOF/MS)快速筛查谷物食品中红木素和降红木素的分析方法。样品用5%醋酸乙腈溶液提取后,采用ZORBAX SB-C18色谱柱分离,以乙腈-0.1%甲酸水溶液(含5 mmol/L乙酸铵)为流动相,梯度洗脱,UPLC-Q-TOF/MS电喷雾正离子模式分析检测。以准分子离子峰的峰面积定量,以化合物的色谱保留时间、精确质量数及碎片离子的精确质量数定性。结果表明,红木素和降红木素分别在1.0~70 mg/kg、0.5~70 mg/kg范围内具有较好的线性关系,相关系数(R)均大于0.99,其定量限分别为1.0 mg/kg、0.5 mg/kg,样品的加标回收率在71.5%~110.6%范围内,相对标准偏差(RSD)均不高于10.2%。该方法简便、快速、准确性高,适用于批量谷物食品的快速筛查。

Low polar volatile constituents from Isodon excisa by GC-MS

An attempt had been made to isolate and identify the low polar volatile constituents from Isodon excisa. The dried plants were heat extracted with ethanol and then extracted with petroleum ether. The constituents were isolated and analyzed by GC-MS and then we retrieved them on NIST08 mass spectrometry database to determine their structures. Finally, successful results were achieved, 111 compounds were obtained and identified. 105 of them were reported for the first time in lsodon excisa and 22 of them were first found in natural products. Thus, the main constituents of it were found to be Sitosterol （33.28%）, 3-Amino-4-pyrazolecarbonitrile （9.55%）

Construction and application of knowledge graph of Treatise on Febrile Diseases

Objective To establish the knowledge graph of“disease-syndrome-symptom-method-formula”in Treatise on Febrile Diseases(Shang Han Lun,《伤寒论》)for reducing the fuzziness and uncertainty of data,and for laying a foundation for later knowledge reasoning and its application.Methods Under the guidance of experts in the classical formula of traditional Chinese medicine(TCM),the method of“top-down as the main,bottom-up as the auxiliary”was adopted to carry out knowledge extraction,knowledge fusion,and knowledge storage from the five aspects of the disease,syndrome,symptom,method,and formula for the original text of Treatise on Febrile Diseases,and so the knowledge graph of Treatise on Febrile Diseases was constructed.On this basis,the knowledge structure query and the knowledge relevance query were realized in a visual manner.Results The knowledge graph of“disease-syndrome-symptom-method-formula”in the Treatise on Febrile Diseases was constructed,containing 6469 entities and 10911 relational triples,on which the query of entities and their relationships can be carried out and the query result can be visualized.Conclusion The knowledge graph of Treatise on Febrile Diseases systematically realizes its digitization of the knowledge system,and improves the completeness and accuracy of the knowledge representation,and the connection between“disease-syndrome-symptom-treatment-formula”,which is conducive to the sharing and reuse of knowledge can be obtained in a clear and efficient way.

Data organization and management of mine typical object spectral libraries

With the development of mining industry,people have obtained profits from it,but they are facing environmental damages.In order to monitor these environmental changes,a spectral library is set up for the spectrum data organization and management of mine typical objects.Most of the spectrum data come from the long-term field measuring in mining area and other spectral libraries.For the data quality control and error detection in the measuring data,an inner precision calculation method is presented and a series of interactive graphical controls are developed for the spectrum visualization and analysis.Through extracting and saving spectrum characters for the mine typical objects,realizs spectrum matching and classification for new measured spectrum samples are realized by using Euclidean distance,Aitchison distance,Pearson correlation coefficient and vector angular cosine methods.Based on the matching result,this work is able to gather dynamically physicochemical environment parameters from the library and gives an early warning for the mine environmental changes.

Assessment of phytoplankton class abundance using fluorescence excitation-emission matrix by parallel factor analysis and nonnegative least squares

The feasibility of using fluorescence excitation-emission matrix(EEM) along with parallel factor analysis(PARAFAC) and nonnegative least squares(NNLS) method for the differentiation of phytoplankton taxonomic groups was investigated. Forty-one phytoplankton species belonging to 28 genera of five divisions were studied. First, the PARAFAC model was applied to EEMs, and 15 fluorescence components were generated. Second, 15 fluorescence components were found to have a strong discriminating capability based on Bayesian discriminant analysis(BDA). Third, all spectra of the fluorescence component compositions for the 41 phytoplankton species were spectrographically sorted into 61 reference spectra using hierarchical cluster analysis(HCA), and then, the reference spectra were used to establish a database. Finally, the phytoplankton taxonomic groups was differentiated by the reference spectra database using the NNLS method. The five phytoplankton groups were differentiated with the correct discrimination ratios(CDRs) of 100% for single-species samples at the division level. The CDRs for the mixtures were above 91% for the dominant phytoplankton species and above 73% for the subdominant phytoplankton species. Sixteen of the 85 field samples collected from the Changjiang River estuary were analyzed by both HPLC-CHEMTAX and the fluorometric technique developed. The results of both methods reveal that Bacillariophyta was the dominant algal group in these 16 samples and that the subdominant algal groups comprised Dinophyta, Chlorophyta and Cryptophyta. The differentiation results by the fluorometric technique were in good agreement with those from HPLC-CHEMTAX. The results indicate that the fluorometric technique could differentiate algal taxonomic groups accurately at the division level.

China's Wetland Databases Based on Remote Sensing Technology

Wetland databases can provide the basic data that necessary for the protection and management of wetlands. A large number of wetland databases have been established in the world as well as in China. In this paper, we review China's wetland databases based on remote sensing(RS) technology after introducing the background theory to the application of RS technology in wetland surveys. A key conclusion is that China's wetland databases are far from sufficient in fulfilling protection and management needs. Our recommendations focus on the use of the hyper-spectral imagery, microwave data, multi-temporal images, and automatic classifications in order to improve the accuracy and efficiency of wetland inventory. Further, attention should also be paid to detect major biophysical features of wetlands and build wetland databases in years after the 1980 s in China. Considering that great gap exists between RS experts and wetland experts, further cooperation between wetland scientists and RS scientists are needed to promote the application of RS in the foundation of wetland databases.

Murine brain tissues with human cytomegalovirus infection: a proteomic study

To establish two-dimensional electrophoresis profiles with high resolution and reproducibility from murine brain tissues by human cytomegalovirus（HCMV） infection and paired murine brain tissues and to identify the differential expression proteins. Methods： Forty Kunming mice were randomly divided into infection group （20） injected with HCMVAD169 and control group （20） injected with saline into their brain. After 30 days, the murine brain tissues by HCMV infection and paired murine brain tissues were separated by two-dimensional gel electrophoresis（2-DE）, analyzed by Image Master 2D software, and identified by peptide mass fingerprint（PMF） and database searching, and make Western blotting analyses the differential expression of individual proteins. Results： Well resolved, reproducible 2-D maps of the above tissues were obtained. Some of the different proteins identified by mass spectrometry（MS） were matched in the SWISS-2D PAGE database, Western blotting analyses were further carried out to verify the differential expression of individual proteins. Conclusion： These data will be valuable for studying the diagnosis of disease at an early stage, mechanisms of pathogenic and the key to the development of anti-HCMV medicine.

Database-Assisted Dynamic Spectrum Access with QoS Guarantees:A Double-Phase Auction Approach

Since FCC's opening for white space(WS) utilization,database-assisted dynamic spectrum access(DSA) has become the de facto solution for the realization of dynamic spectrum sharing(DSS),due to its simplicity and compatibility with commercial off-the-shelf(COTS) devices.It is envisioned that such technology will strongly support the prosperous wireless multimedia networking(WMN) applications with satisfying QoS guarantees in the future.However,how to counter the time-frequency variant property when exploiting the WS spectrum for the provision of these services to secondary users(SUs) still remains a great challenge.In such context,a dynamic secondary access scheme for database-assisted spectrum sharing networks is proposed in this paper.In the beginning,the spectrum requirements of SUs for diverse services are modeled by considering the minimum required service data-rate and spectrum access duration.Afterwards,the spectrum demand evaluation and bidding policy are formulated based on the service classes of SUs.Furthermore,a doublephase(DP) spectrum allocation scheme,which consists of the initial resource allocation phase and resource allocation adjustment phase,is carefully designed for DSA.Finally,extensive simulations are conducted and the results demonstrate that our scheme can increase the spectrum trading revenue and adapt to varying service requirements.

RIPP Works on Crude Formulation Technique to Grapple with Refiners' Tough Problems

Currently ＂The Crude Formulation Technique＂ developed by the SINOPEC Research Institute of Petroleum Processing（RIPP） has passed the technical review sponsored by the Sinopec Corp.This technique by means of adopting the advanced algorithm on the basis of the crude assay data bank and the large crude spectroscopic database can intelligently blend together different kinds of crude oils to obtain multiple crude formulations, the quality of which is quite close to the target crude in a bid to provide technical support to the refining enterprises in the area of crude procurement and sustained property stabilization of crude oils pro-cessed thereby.

Exploration to the disease spectrum of acupoint catgut-embedding therapy

Objective To explore the clinically indicated diseases of acupoint catgut-embedding therapy, and summarize and analyze the disease spectrum of acupoint catgut-embedding therapy. Methods By literature research and data mining technique, the clinical study papers relevant to acupoint catgut-embedding therapy published from 1971 to June 2011 were selected, entered and verified, then the effective information were extracted, and finally, the disease spectrum were summarized. Results Acupoint catgut-embedding therapy is indicated for 103 diseases, involving 6 departments, of which there are 50 internal diseases, which is the most, accounting to 48.54%, and 15 surgical diseases, 12 ENT diseases, 11 gynecological diseases and 11 dermatological diseases, and 4 pediatric diseases, which is the least. Meanwhile, according to the rule of ＂Efficacy acupuncture grading disease spectrum＂, the diseases treated with this therapy were graded preliminarily into grade Ⅰ with 26 diseases, grade Ⅱ with 30 diseases, and grade Ⅲ with 8 diseases. Conclusion Acupoint catgut-embedding therapy can be used widely in clinical treatment with much broader disease spectrum, and it is worthy of being spread and applied.

What do we know about parasitic plants and the leaf economic spectrum?

The leaf economic spectrum(LES)quantifes correlations between key leaf traits across vascular plants and distills much of the variation in these traits to a single axis.The LES,remarkable in its near universality,has been extensively researched across a variety of contexts.However,parasitic plants relationship to the LES framework remains relatively unexplored.Because the LES is,in part,driven by physiological tradeoffs in the acquisition of carbon(C),in theory heterotrophy in parasitic plants,which supplants some of the essential functions of leaves,could lead to departures from the LES.Using global leaf trait data from the TRY database,this work assessed the overall representation of parasitic plants in the TRY database,then compared the LES suite of leaf traits in parasitic plants to their non-parasitic counterparts.Despite their unique physiology,parasitic plants did not deviate dramatically from the LES,although there were examples of differences in position on the LES and relationships among traits.Perhaps more importantly,parasitic plants are not well represented in the TRY database,making any conclusions here premature.

AntarcticaLC2000：The new Antarctic land cover database for the year 2000

Antarctica plays a key role in global energy balance and sea level change.It has been conventionally viewed as a whole ice body with high albedo in General Circulation Models or Regional Climate Models and the differences of land cover has usually been overlooked.Land cover in Antarctica is one of the most important drivers of changes in the Earth system.Detailed land cover information over the Antarctic region is necessary as spatial resolution improves in land process models.However,there is a lack of complete Antarctic land cover dataset derived from a consistent data source.To fill this data gap,we have produced a database named Antarctic Land Cover Database for the Year 2000(AntarcticaLC2000) using Landsat Enhanced Thematic Mapper Plus(ETM+) data acquired around 2000 and Moderate Resolution Imaging Spectrometer(MODIS) images acquired in the austral summer of 2003/2004 according to the criteria for the 1:100000-scale.Three land cover types were included in this map,separately,ice-free rocks,blue ice,and snow/firn.This classification legend was determined based on a review of the land cover systems in Antarctica(LCCSA) and an analysis of different land surface types and the potential of satellite data.Image classification was conducted through a combined usage of computer-aided and manual interpretation methods.A total of 4067 validation sample units were collected through visual interpretation in a stratified random sampling manner.An overall accuracy of 92.3%and the Kappa coefficient of 0.836 were achieved.Results show that the areas and percentages of ice-free rocks,blue ice,and snow/firn are 73268.81 km2(0.537%),225937.26 km2(1.656%),and 13345460.41 km2(97.807%),respectively.The comparisons with other different data proved a higher accuracy of our product and a more advantageous data quality.These indicate that AntarcticaLC2000,the new land cover dataset for Antarctica entirely derived from satellite data,is a reliable product for a broad spectrum of applications.

Comprehensive profiling of lysine acetylome in Staphylococcus aureus

The Gram-positive bacterium Staphylococcus aureus(S.aureus)is a wide spread common opportunistic pathogen that causes a wide variety of infectious diseases,from benign skin infections to life-threatening diseases such as the methicillin-resistant Staphylococcus aureus(MRSA)infection.Although emerging evidence suggests that lysine acetylation may play critical roles in bacterial physiology,the atlas of acetylome in S.aureus has not been studied.To comprehensively profile protein lysine acetylation in S.aureus,we used an integrated approach that combined immune affinity peptide enrichment using anti-lysine acetylation antibody,high-pH HPLC fractionation,and HPLC/mass spectrometry analysis.This study led to the identification of 1361 non-redundant acetylation sites on 412 proteins found in a search of S.aureus protein database extracted from the Swiss-Prot database.We further performed bioinformatic analysis to characterize this modification,including gene ontology annotation,protein-protein interaction,and domain analysis of the acetylation sites.We found that the acetylated proteins were enriched in multiple biological pathways,such as ribosomal function and energy metabolism.Our data provides a rich source for functional studies of lysine acetylation in S.aureus.