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Advancements in liquid chromatography and mass spectrometry over the last decades have led to a significant development in mass spectrometry-based proteome quantification approaches. An increasingly attractive strategy is multiplex isotope labeling, which significantly improves the accuracy, precision and throughput of quantitative proteomics in the data-dependent acquisition mode. Isotope labeling-based approaches can be classified into MS1-based and MS2-based quantification. In this review, we give an overview of approaches based on chemical isotope labeling and discuss their principles, benefits, and limitations with the goal to give insights into fundamental questions and provide a useful reference for choosing a method for quantitative proteomics. As a perspective, we discuss the current possibilities and limitations of multiplex, isotope labeling approaches for the data-independent acquisition mode, which is increasing in popularity.

Terra Nova, 24, 339–350, 2012 Abstract Studies of regional plate-scale processes that may influence the exhumation of ultra-high pressure (UHP) metamorphic rocks are few despite their potential importance. Here, we review and summarize available age constraints along with the Qinling-Dabie Shan orogen, which separates the North China Block (NCB) from the South China Block (SCB). We find that collision-related events in the west and extension-related events in the east, where the large Dabie Shan UHP terrane is located, were contemporaneous. Available palaeomagnetic data indicate clockwise rotation of the SCB relative to the NCB during this time. Previous work indicated that the collision propagated from east to west where indentation of the SCB into the Qinling-Dabie Shan orogen was active in the Hannan Dome area at 165 ± 3 Ma as constrained by new 40Ar/39Ar dates on synkinematic sericite in an indentation-related mylonitic shear zone. While this contraction was occurring in the west, exhumation of the UHP terrane was occurring in the Dabie Shan in the east. We propose that the collision of the SCB with the NCB occurred not only in a scissor-like fashion, as previously suggested, but also involved a later rotation about a pole west of the Dabie Shan during the closure of the Mianlue Ocean. As a consequence of this rotation, extension occurred between the South China Block and North China Block east of the pole of rotation leading to extensional exhumation of the Dabie Shan orogen. This microcontinent-scale rotation of the SCB may have provided an important component in the exhumation of the largest UHP terrane in the world.

“Water level” is used in the estimation of receiver function in frequency-domain to replace the value that is smaller than the level in vertical component, so as to improve the stability of deconvolution. However this will reduce the resolution of receiver function, especially the lower-frequency information which has significant meaning to study the structure of crust and upper mantle. Furthermore, though the effective source function actually has a finite length, the vertical component is often complicated by the later phases and presents strong energy on the seismic records. So it will seriously affect the resolution of receiver function if the long record is used as an effective source function. In order to estimate a stable receiver function with high resolution in frequency-domain, this paper proposes to improve the usage of “water level” and to select an appropriate “water level” and effective source function length by tradeoff method. Its application to the observed data and model indicates that the method in this paper is effective to estimate receiver functions with high stability and resolution in frequency-domain.

The Moho discontinuity is often deformed by complex forces in tectonic zones, which may lead to a dipping Moho locally. In order to obtain accurate crustal Vp/Vs ratio for these regions, this paper proposed a H-κ-θ stacking method to estimate the crustal Vp/Vs and thickness, which considers the responses of a dipping Moho. Both radial and tangential receiver functions were stacked, so that improves the scanning precision. Results of its application to southeastern Tibet indicate that the crustal thickness beneath southeastern Tibet varied notably. The average crustal thickness is about 60 km, 47 km and 43 km in Songpan-Garze fold system, Sichuan basin and Yangtze platform, respectively, with a normal value in Sanjiang fold zone and southeastern Yangtze platform. The crustal Vp/Vs ratio is higher in the region between the Songpan-Garze fold system and Yangtze platform, and is abnormally highest to the west of Sichuan basin (> 1.88). We presume that the eastward crustal material flow was resisted by the Sichuan basin with high strength, and accumulated at west of Sichuan, consequently resulting in the unusual high Vp/Vs anomaly.

Along the line Yanchuan–Baotou–Mandula in the Ordos basin and adjacent Yinshan mountainous area in the north in North China, a wide-angle reflection and refraction seismic sounding has been carried out yielding Pg wave data of high resolution. By the traveltime differential tomographic imaging, traveltime inversion of the Pg wave field is performed to determine velocity distribution of the upper crust, undulation of sedimentary formation and crystalline basement along the profile. And geological interpretation to these features is made. The result shows that the upper crust below the Ordos basin is of a double-layer structure, with a distinct interface between the upper and lower layers. The upper layer is characterized by low velocity and big gradients in vertical direction, while the lower layer has low velocity and changes gently. In the light of the velocity distribution in the upper crust of the study area, it is suggested that the sedimentary formation and crystalline basement undulate in NS direction, generating a series of rising and falling structures. From south to north, they are the depression south to Yulin, Yulin-Daotu swell, listric depression from northern Daotu to the fault on the northern edge of Ordos and secondary structure in it, and Hohhot-Baotou depression and its interior faults. In the north, seismic wave velocity in the upper crust beneath the Yinshan Mountains (Mt.) is obviously higher than that below the areas on the both sides, exhibiting a pattern of longitudinal belt. It reflects the feature of the crystalline basement of this area, which is associated with collage and accretion of several blocks such as the Wula'er Shan Mt., Se'erteng Mt., Hejiao batholith, and Bayan Obo group. Beneath the Yinshan Mt. the upper crust is also of a double-layer structure, though its refraction interface of the basement is not so clear as that below the Ordos basin. Based on the structures of sedimentary formation and undulation of the crystalline basement of the study area, we have discussed the sedimentary features and hydrocarbon prospects of every depression along the profile.

We selected broadband teleseismic waveform data recorded by the Gansu Digital Seismic Network to study the crustal and upper mantle structure beneath the Northeastern Tibetan Plateau. The crustal thickness and VP/VS ratio are estimated by the grid-search method using crustal conversion and multiples, assuming an average P-wave velocity in the crust. Teleseismic P waveform modeling is carried out to investigate the S-wave velocity structure, assuming the fixed VP/VS value inferred from the grid-search method. Our results show that the crust is 50~55km thick beneath Qilian terrane, and about 45 km beneath the Hexi Corridor and Qaidam terrane. The VP/VS ranges from 1.66~1.85, and the Poisson's ratio is about 0.215~0.294. Our results also show that the Moho interface is sharp beneath the Northeastern Tibetan Plateau. Both of the low-to-normal Poisson's ratio and the sharp Moho do not support the argument of significant partial melting in the upper-to-middle crust and underplating beneath the lower crust of the Northeastern Tibetan Plateau. The existence of anticorrelation between VP/VS and the crustal thickness strongly suggests that the crust is mainly composed of felsic mineral in the northeastern Tibetan crust. The seismic evidence may indicate that the thickened crust, mostly in its upper part, is probably due to the successive intracrustal thrusts.

Teleseismic conversion and multiple waves recorded by the INDEPTH III seismic array have been used to investigate the crustal thickness and VP/VS ratios of the central Tibetan Plateau. The comparison with crustal thicknesses obtained from other studies shows good agreement, which suggests that our measurements are reliable. Our results reveal that the crustal thickness is 65±5km beneath central Tibet. On the average, the Moho beneath Qiangtang is 5~6km shallower than that below the Lhasa terrane. A ~10km Moho offset occurs along the BNS, which maybe the result of northward subduction of the Lhasa mantle lid beneath the Qiangtang terrane affected by the India-Asia collision. Due to extensive crustal melting/fluid beneath the central Tibet, the average crust Poission's ratios are high (0.25~0.32). The high Poission's ratio abnormality in the northern Lhasa may be related to the Bong Co-Lhari fault. Another high Poission's ratio abnormality located on the northern Qiangtang terrane (st36~st40) can be related to the crustal partial melting arising from the high heat flux from abnormal upper-mantle beneath the north-central plateau.

Considering the limitation of the implying assumption of the traditional Hilbert transform, that is, the length of time series is infinite, a multi-taper method (MTM) is introduced into the Hilbert transform of three short-time series to construct a complex covariance matrix. Time-varying polarization parameters can be measured by computing the eigenvalues and eigenvectors of the covariance matrix analytically. Based on the polarization characteristics of special wave types and the measured parameters of actual seismic data, some signals can be identified, and then can be separated using some adaptive filters, such as linear-cosine function or Gaussian weighting function filters. Example of actual three-component earthquake data demonstrates that it is available to identify and separate some special seismic responses.

In numerical modeling elastic wave equations, an artificial boundary must be given around the area in which the wave propagation is interesting. Unlike the wave filed within the area, the wave filed on the boundary cannot be calculated using the center difference method, thus the numerical calculation precision is decreased greatly, and as a result reflection is generated. For avoiding the reflection generating on the boundary, the delay boundary conditions method is proposed by this paper. On the basis of the fact that there are the same phase-delay and the same coefficient of amplitude attenuation on equidistant particles in the direction of wave propagation, the phase-delay and the coefficient of amplitude attenuation on the boundary can be calculated using the wave field within the boundary. Thus the precision of the wave field calculation on the boundary is improved and the reflection is removed.

Single-crystalline InSb dendrites were prepared by a sonochemical coreduction route. The result of supplementary experiments shows the experiment was carried out along the coreduction mechanism. It is found that the ultrasonic power, reaction temperature and solvent played crucial roles in the crystallinity and yield of products.

per grid coated with a layer of amorphous carbon. Crystal structures were deter-mined by SAED (using a JEM-200CX TEM), using an accelerating voltage of200 kVand a double-tilt sample holder.Measurements of Raman spectra were performed on a Spex 1403 Ramanspectrometer under a back scattering geometry. A blue line (514.5 nm) of Ar