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1,3-Dienes are common scaffolds in biologically active natural products as well as building blocks for chemical synthesis. Developing efficient methods for the synthesis of diverse 1,3-dienes from simple starting materials is therefore highly desirable. Herein, we report a Pd(II)-catalyzed sequential dehydrogenation reaction of free aliphatic acids via β-methylene C–H activation, which enables one-step synthesis of diverse E,E-1,3-dienes. Free aliphatic acids of varying complexities, including the antiasthmatic drug seratrodast, were found to be compatible with the reported protocol. Considering the high lability of 1,3-dienes and lack of protecting strategies, dehydrogenation of aliphatic acids to reveal 1,3-dienes at the late stage of synthesis offers an appealing strategy for the synthesis of complex molecules containing such motifs.

Enolate alkylation and conjugate addition into an α,β-unsaturated system have served as long-standing strategic disconnections for the installation of α- or β-substituents on carbonyl-containing compounds. At the onset of our efforts to develop C–H activation reactions for organic synthesis, we set our eye toward developing asymmetric β-C–H activation reactions of aliphatic acids with the perspective that this bond-forming event could serve as a more flexible retrosynthetic surrogate for both canonical carbonyl-related asymmetric transformations.

Retrospective review.

Pd(II)-catalyzed nondirected C–H functionalization of heteroarenes is a significant challenge for the following reasons: poor reactivity of electron-deficient heterocycles and the unproductive coordination of Lewis basic nitrogen atoms. Existing methodologies using palladium catalysis often employ a large excess of heterocycle substrates to overcome these hurdles. Despite recent advances in nondirected functionalization of arenes that allow them to be used as limiting reagents, the reaction conditions are incompatible with electron-deficient heteroarenes. Herein we report a dual-ligand catalyst that enables Pd(II)-catalyzed nondirected C–H olefination of heteroarenes without using a large excess of substrate. In general, the use of 1–2 equiv of substrates was sufficient to obtain synthetically useful yields. The reactivity was rationalized by the synergy between two types of ligands: a bidentate pyridine–pyridone ligand promotes C–H cleavage; the monodentate heterocycle substrate acts as a second ligand to form a cationic Pd(II) complex that has high affinity for arenes. The proposed dual-ligand cooperation is supported by a combination of X-ray, kinetics, and control experiments.

Local concentrations of mutations are well known in human cancers. However, their three-dimensional spatial relationships in the encoded protein have yet to be systematically explored. We developed a computational tool, HotSpot3D, to identify such spatial hotspots (clusters) and to interpret the potential function of variants within them. We applied HotSpot3D to >4,400 TCGA tumors across 19 cancer types, discovering >6,000 intra- and intermolecular clusters, some of which showed tumor and/or tissue specificity. In addition, we identified 369 rare mutations in genes including TP53, PTEN, VHL, EGFR, and FBXW7 and 99 medium-recurrence mutations in genes such as RUNX1, MTOR, CA3, PI3, and PTPN11, all mapping within clusters having potential functional implications. As a proof of concept, we validated our predictions in EGFR using high-throughput phosphorylation data and cell-line-based experimental evaluation. Finally, mutation–drug cluster and network analysis predicted over 800 promising candidates for druggable mutations, raising new possibilities for designing personalized treatments for patients carrying specific mutations.

The sub-seismic faults are below the limit of seismic resolution, and present in 3D seismic data. In general, the sub-seismic faults are providing cross-stratigraphic pathways for fluid expulsion in the tight reservoir. A workflow to analyze sub-seismic faults prediction over different scales is described in this paper. This requires very detailed fault detection in order to bridge the information gap between seismic data and sub-seismic faults. Based on the seismic signal singular value analysis, we made predictions about the sub-seismic faults. We interpreted fault in seismic, and seismic attributes volumes at scales above dozens meters. The seismic signal singular value was performed on a detailed interpreted 3D volume to predict the sub-seismic fault, at a scale below seismic resolution. The modeling results show that considerable seismic signal singular value is observed less than 20 m from the seismic volume. We linked the real data volume from the modeled parameters, and used the singular value as a proxy for sub-seismic faults. With this method we can predict the sub-seismic faults combined with structure in areas. Furthermore, knowing other geological data we can predict the possible leakage and overflow when drilling horizontal well and reduce drilling risk.

The Donghe Sandstone formation (DS fm. for simplicity) presents an excellent thin condensate gas reservoir in LG34 well area, Tarim Basin. Unfortunately, drilling results show that the reservoir is thin, deeply buried (below 5000m) and mix lithologies. Pre-stack inversion and fluid identification is implemented in this area. The feasibility and validity of pre-stack inversion for this kind of reservoir is tested, since that application of pre-stack inversion in this area is for the first time. A new rock physics model is used for estimating rock velocities and elastic attributes, and cross-plots of Poisson's ratio (σ) again LambdaRho (λρ) is found to be more favorable for lithofacies identification. Then, pre-stack inversion which uses seismic data with careful amplitude processing is performed to predict the reservoir. The inversion results agree and tie with most wells, suggesting that the pre-stack inversion is viable process for this complex lithological reservoir prediction in the area.

Fractured reservoirs always show anisotropic amplitude features, i.e. the reflection amplitude of seismic waves varies with offset and azimuth (AVOZ). A noise attenuation fracture inversion algorithm is presented for fracture detection based on P-wave AVOZ. The conventional inversion method always fails when applied to limited azimuth data because of the existence of noise. In our inversion algorithm, special attention is paid to suppressing the noise during inversion, to overcome the limitation of the conventional inversion method on limited azimuth data. Numerical models are employed to illustrate the effectiveness of the method. The inversion algorithm is then applied to Tazhong 45 area field data which is acquired under limited azimuth distribution. Compared with cores and fullbore formation microimage (FMI), the inverted results (fracture density and orientation) are reasonable, suggesting that the inversion algorithm is feasible for fracture prediction in the Tarim Basin.

The carbonate reservoirs in the Tarim Basin are characterized by low matrix-porosity, heterogeneity and anisotropy, which make it difficult to predict and evaluate these reservoirs. The reservoir formations in Lundong area experienced a series of diagenesis and tectonic evolution stages. And secondary storage spaces such as fractures and dissolution caves were developed while nearly all the primary pores have disappeared. Based on a summary of different types of storage spaces and their responses in conventional logs, FMI and full waveform sonic logs which are sensitive to different reservoirs, the comprehensive probability index (CPI) method is applied to evaluating the reservoirs and a standard of reservoir classification is established. By comparing the evaluation results with actual well-logging results, the method has proven to be practical for formation evaluation of carbonate reservoirs, especially for the fractured carbonate reservoirs. In reservoir fluid identification, the multivariate stepwise discriminant analysis (MSDA) method is introduced. Combining the CPI method and MSDA method, comprehensive formation evaluation has been performed for fractured and caved carbonate reservoirs in the Tarim Basin. Additionally, on the basis of secondary pore inversion results, another new method of formation evaluation is also proposed in the discussion part of this paper. Through detailed application result analysis, the method shows a promising capability for formation evaluation of complex carbonate reservoirs dominated by various secondary pores such as holes, caves, and cracks.

Conventional seismic exploration method based on post-stack data usually fails to identify the distribution of fractured and caved carbonate reservoirs in the Tarim Basin, so the rich pre-stack information should be applied to the prediction of carbonate reservoirs. Amplitude-preserved seismic data processing is the foundation. In this paper, according to the feature of desert seismic data (including weak reflection, fast attenuation of high frequency components, strong coherent noises, low S/N and resolution), a set of amplitude-preserved processing techniques is applied and a reasonable processing flow is formed to obtain the high quality data. After implementing a set of pre-stack amplitude-preserved processing, we test and define the kernel parameters of amplitude-preserved Kirchhoff PSTM (pre-stack time migration) and subsequent gathers processing, in order to obtain the amplitude-preserved gathers used to the isotropic pre-stack inversion for the identification of caved reservoirs. The AVO characteristics of obtained gathers fit well with the synthetic gathers from logging data, and it proves that the processing above is amplitude-preserved. The azimuthal processing techniques, including azimuth division and binning enlargement, are implemented for amplitude-preserved azimuthal gathers with the uniform fold. They can be used in the anisotropic inversion to detect effective fractures. The processing techniques and flows are applied to the field seismic data, and are proved available for providing the amplitude-preserved gathers for carbonate reservoir prediction in the Tarim Basin.

The major storage space types in the carbonate reservoir in the Ordovician in the TZ45 area are secondary dissolution caves. For the prediction of caved carbonate reservoir, post-stack methods are commonly used in the oilfield at present since pre-stack inversion is always limited by poor seismic data quality and insufficient logging data. In this paper, based on amplitude preserved seismic data processing and rock-physics analysis, pre-stack inversion is employed to predict the caved carbonate reservoir in TZ45 area by seriously controlling the quality of inversion procedures. These procedures mainly include angle-gather conversion, partial stack, wavelet estimation, low-frequency model building and inversion residual analysis. The amplitude-preserved data processing method can achieve high quality data based on the principle that they are very consistent with the synthetics. Besides, the foundation of pre-stack inversion and reservoir prediction criterion can be established by the connection between reservoir property and seismic reflection through rock-physics analysis. Finally, the inversion result is consistent with drilling wells in most cases. It is concluded that integrated with amplitude-preserved processing and rock-physics, pre-stack inversion can be effectively applied in the caved carbonate reservoir prediction.

The carbonate reservoirs in the Tarim Basin are characterized by anisotropy and strong heterogeneity. Combined with an integrated analysis of data from seismic, geology, and drilling results, a series of attributes which are suitable for fractured and caved carbonate reservoir prediction is discussed, including amplitude, coherence analysis, spectra decomposition, seismic absorption attenuation analysis and impedance inversion. Moreover, 3-D optimization of these attributes is achieved by integration of multivariate discriminant analysis and principle component analysis, where the logging data are taken as training samples. Using the optimized results, the spatial distribution and configuration features of the caved reservoirs can be chara cterized in detail. This technique not only improves the understanding of the spatial distribution of current reservoirs but also provides a significant basis for the discovery and production of carbonate reservoirs in the Tarim Basin.

Secondary storage spaces with very complex geometries are well developed in Ordovician carbonate reservoirs in the Tarim Basin, which is taken as a study case in this paper. It is still not clear how the secondary storage space shape influences the P- & S-wave velocities (or elastic properties) in complex carbonate reservoirs. In this paper, three classical rock physics models (Wyllie timeaverage equation, Gassmann equation and the Kuster-Toksöz model) are comparably analyzed for their construction principles and actual velocity prediction results, aiming at determining the most favourable rock physics model to consider the influence of secondary storage space shape. Then relationships between the P- & S-wave velocities in carbonate reservoirs and geometric shapes of secondary storage spaces are discussed from different aspects based on actual well data by employing the favourable rock physics model. To explain the influence of secondary storage space shape on VP-VSrelationship, it is analyzed for the differences of S-wave velocities between derived from common empirical relationships (including Castagna’s mud rock line and Greenberg-Castagna VP-VSrelationship) and predicted by the rock physics model. We advocate that VP-VSrelationship for complex carbonate reservoirs should be built for different storage space types. For the carbonate reservoirs in the Tarim Basin, the VP-VSrelationships for f ractured, fractured-cavernous, and fractured-hole-vuggy reservoirs are respectively built on the basis of velocity prediction and secondary storage space type determination. Through the discussion above, it is expected that the velocity prediction and the VP-VSrelationships for complex carbonate reservoirs should fully consider the influence of secondary storage space shape, thus providing more reasonable constraints for prestack inversion, further building a foundation for realizing carbonate reservoir prediction and fluid prediction.

Fractured reservoirs are an important target for oil and gas exploration in the Tarim Basin and the prediction of this type of reservoir is challenging. Due to the complicated fracture system in the Tarim Basin, the conventional AVO inversion method based on HTI theory to predict fracture development will result in some errors. Thus, an integrated research concept for fractured reservoir prediction is put forward in this paper. Seismic modeling plays a bridging role in this concept, and the establishment of an anisotropic fracture model by Discrete Fracture Network (DFN) is the key part. Because the fracture system in the Tarim Basin shows complex anisotropic characteristics, it is vital to build an effective anisotropic model. Based on geological, well logging and seismic data, an effective anisotropic model of complex fracture systems can be set up with the DFN method. The effective elastic coefficients, and the input data for seismic modeling can be calculated. Then seismic modeling based on this model is performed, and the seismic response characteristics are analyzed. The modeling results can be used in the following AVO inversion for fracture detection.

A novel class of light harvesting conjugated block copolymers, with electron-donating conjugated blocks (D) connected to electron-accepting conjugated blocks (A) via non conjugated and flexible bridge chains (B), has been designed, synthesized, and characterized. Specifically, Dis a decyloxy-substituted polyphenylenevinylene (C10−PPV). A1and A2are PPVs with sulfone (SO2) acceptor moieties substituted on every other phenylene unit. A1carries two decyloxy groups on every phenylene unit, while in A2, half of the phenylene units are unsubstituted. The optical energy gaps are 2.24 eV for the donor block (D), 2.33 and 2.45 eV for A1and A2acceptor blocks. LUMO level offsets are 0.24 and 0.16 eV for D/A1and D/A2pairs, respectively. Comparing the photoluminescence from both films and solutions, very large red shifts (71 and 74 nm for A1and A2respectively) were observed in the two acceptor polymers. These red shifts in the emission spectra were more than twice as much as that observed for D(31 nm). The (DBA1B)nand (DBA2B)nblock copolymer films exhibited improved processability and optoelectronic properties when compared with the corresponding films composed of donor/acceptor blends. Atomic force microscopic (AFM) studies of D, A1, and A2films were also undertaken to observe the degree of aggregation in the films. The results indicate the tendency of intermolecular aggregation increases as A2> D> A1. AFM topological images revealed that large aggregates of several hundreds of nanometers formed in donor/acceptor blend films, while in block copolymer films, domain sizes were similar to individual block sizes which are 1 order of magnitude smaller than in the blend.

Donor‐ or acceptor‐substituted polythiophenes have many potential applications in optoelectronics. Fluorinated polythiophenes are particularly attractive because of the presence of fluorine, which can withdraw electrons and also improve polymer chemical stability. Because of the promising future of these polymers, there has been much interest in identifying favorable synthetic routes to new fluorinated monomers and polymers. In this study, the monomer had an electron‐withdrawing fluorinated ester and was derived from 3‐thiophene carboxylic acid and 2,2,3,3,4,4,4‐heptafluoro‐1‐butanol. The synthesis of an n‐type fluorinated and terminal‐functionalized polythiophene was accomplished with the Ullmann coupling reaction. A polymer soluble in tetrahydrofuran was obtained with a molecular weight of approximately 15,000 g/mol. In solution, it exhibited a band gap of 2.4 eV, and the photoluminescent excitation and emission maxima were 370 nm and 555 nm, respectively. All peaks were bathochromically shifted when they were measured in the solid state. The glass‐transition and decomposition (in air) temperatures were 129 and 493 °C, respectively. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 4280–4287, 2005

The synthesis, processing, and characterization of new crosslinked functional polymer thin films derived from fumaryl chloride and maleic anhydride is presented. Experimental data demonstrated that this is a versatile, convenient, and cost-effective method of fabricating ultrastructure crosslinked and functional polymer thin films for potential nonlinear optical (NLO) or other applications where molecular orientation is required. The unsaturated and processable polyester thin films are capable of crosslinking in air to form a hardened lattice under a variety of conditions, including both thermal and photoinitiated crosslinking. The thermal stability of the second harmonic (SHG) signal for a crosslinked NLO thin film was stable at temperatures up to 150°C, which is in contrast to uncrosslinked polymers whose SHG signals typically decreased over 50% below 100°C. Because of the lack of NH/OH groups and their vibrational overtones in the polymer, these crosslinked polyester systems have a great potential for low optical loss applications at 1550 nm communication wavelength. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 317–322, 2004

Electrically conductive semi-IPNs based on polyaniline and crosslinked polyvinylacetate were prepared. Polyaniline successfully percolated through the crosslinked PVAc networks and the resulting semi-IPNs show a continuous network morphology. The conductivity of the semi-IPN increases with increasing content of polyaniline and increasing acidity used during the polymerization of the polyaniline. The conductivity of the semi-IPN is 0.13 S/cm, with the highest polyaniline content of 19.3 wt %. The depression of polyaniline with temperature change is smallest followed by the depression of semi-IPN of the polyaniline/crosslinked polyvinylacetate, which is considerably smaller than the depression of crosslinked polyvinylacetate. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2287–2293, 2002

Gene fusions represent an important class of somatic alterations in cancer. We systematically investigated fusions in 9,624 tumors across 33 cancer types using multiple fusion calling tools. We identified a total of 25,664 fusions, with a 63% validation rate. Integration of gene expression, copy number, and fusion annotation data revealed that fusions involving oncogenes tend to exhibit increased expression, whereas fusions involving tumor suppressors have the opposite effect. For fusions involving kinases, we found 1,275 with an intact kinase domain, the proportion of which varied significantly across cancer types. Our study suggests that fusions drive the development of 16.5% of cancer cases and function as the sole driver in more than 1% of them. Finally, we identified druggable fusions involving genes such as TMPRSS2, RET, FGFR3, ALK, and ESR1in 6.0% of cases, and we predicted immunogenic peptides, suggesting that fusions may provide leads for targeted drug and immune therapy.