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Cu-catalyzed C–H late-stage functionalization were employed to modify 5-nitrofuran drugs. Compound 1 and 18 were the most active among all compounds, and the cell cytotoxicity assays were conducted.

Quadrotors possess traits such as under-actuation, nonlinearity, and strong coupling. Quaternions are primarily used for attitude calculations in drones, with error quaternions seldom being employed directly in the control of specific quadcopter drones. This paper focuses on the low tracking accuracy and weak anti-interference ability of quadcopter drones in trajectory-tracking control. By establishing the quadcopter quaternion model, a controller based on quaternion error is designed through a combination of fractional-order PID control with S-plane control. Trajectory-tracking experiments demonstrate that, in comparison with fractional-order PID, this method exhibits strong wind disturbance resistance and high tracking accuracy.

Purpose: The most common genetic lesions in pancreatic ductal adenocarcinoma (PDAC) have been identified. However, significant gaps still exist in our understanding of how such genetic alterations act in concert to induce PDAC development. In this study, we investigated the mechanism of tumorigenic transformation in the immortalized human pancreatic ductal epithelial (HPDE) cell line by sequentially introducing PDAC signature alterations into this cell line.Experimental Design: The phenotype for stable expression of mutant K-ras, Her2, p16/p14shRNA, and Smad4shRNA in HPDE cells was examined by assays for cell proliferation, migration, invasion, soft agar, and orthotopic tumorigenesis. The mechanisms of tumorigenic transformation were further explored by gene expression profiling and pathway analyses.Results: The transformed cells exhibited enhanced proliferation, migration, and invasion, displayed anchorage-independent growth in soft agar, and grew orthotopic tumors with some histopathologic features of PDAC. We found that Smad4 played key roles in the tumorigenic transformation of HPDE cells. We further found that MDM2 and Bmi-1 were overexpressed in the tumorigenic HPDE cells and that Bmi-1 overexpression was regulated by Smad4. Ingenuity Pathway Analysis software analysis of microarray data revealed that dysregulation of integrin-linked kinase signaling and the cell cycle were the most significant changes involved in tumorigenic transformation. Altogether, this cell culture model closely recapitulated human pancreatic carcinogenesis from gene lesions, activation of specific signaling pathways, and some histopathologic features.Conclusion: The combination of activated K-ras and Her2 with inactivated p16/p14 and Smad4 was sufficient and essential to transform HPDE cells, thus revealing the potential tumorigenic mechanism. Clin Cancer Res; 19(3); 549–59. ©2012 AACR.

PDF file - 169K, Supplementary Fig. 2. Cell migration and invasion abilities of HPDE cells with expression of mutant K-ras, Her2, p16/p14shRNA, and Smad4shRNA.

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PDF file - 77K, Supplementary Table 1. Summary of cell proliferation, migration, and invasion; anchorageindependent growth; and tumor incidence in NOD/SCID mice in various HPDE cell lines.

PDF file - 74K, Supplementary Table 2. The most significant changes in gene expression for cell line HPDE/Kras/ Her2/p16p14shRNA/Smad4shRNA versus cell line HPDE/K-ras/Her2/p16p14shRNA in cDNA microarray analysis.

PDF file - 96K, Supplementary Fig. 3. Confirmation of gene expression change of BMP7 and GRB10 in cDNA microarray analysis.

Supplementary Tables 1-2 from TrkBT1 Induces Liver Metastasis of Pancreatic Cancer Cells by Sequestering Rho GDP Dissociation Inhibitor and Promoting RhoA Activation

Supplementary Figure 2 from TrkBT1 Induces Liver Metastasis of Pancreatic Cancer Cells by Sequestering Rho GDP Dissociation Inhibitor and Promoting RhoA Activation

Supplementary Figure 1 from TrkBT1 Induces Liver Metastasis of Pancreatic Cancer Cells by Sequestering Rho GDP Dissociation Inhibitor and Promoting RhoA Activation

Supplementary Figure 3 from TrkBT1 Induces Liver Metastasis of Pancreatic Cancer Cells by Sequestering Rho GDP Dissociation Inhibitor and Promoting RhoA Activation

Tarim is inferred to have a close connection with East Gondwana during the Ordovician, but the position in East Gondwana remains controversial. In this study, we report 316 detrital zircons U-Pb data from three samples of Ordovician Malieziken Group sedimentary rocks, collected in the Qiate Section, Southwest Tarim, provided new insight into the position of Tarim in East Gondwana. Detrital zircons data indicated the maximum depositional age for the three samples is 489.5 Ma, 478.1 Ma, and 465 Ma, respectively, indicating the Qiate and Kandilike Formation of the Malieziken Group was deposited in Early—Middle Ordovician. The detrital zircons are characterized by two main peaks at ~490 Ma and ~1100 Ma, and three subordinate peaks at ~880 Ma, ~1400 Ma, and ~1650 Ma, suggesting most of the detritus of Malieziken Group from the South Kunlun Terrane (SKT) itself. However, the source of the ~1650 Ma peak is not found in the Tarim block, and the ~1400 Ma and the ~1650 Ma peak are absent in the middle of the three samples, which implied that there is an exotic source. The Paleoproterozoic sediment strata in the Albany–Fraser belt shows dominant peaks at ~1400 Ma and ~1650 Ma may have been transported to SKT and redeposited in the Malieziken Group during the Ordovician. The Malieziken Group shows detrital zircon age patterns resembling those of East Sumatra, Lhasa, and Western Australia which, in combination with the Albany–Fraser belt provenance, enables us to propose that the Tarim block has a close linkage with Western Australia, East Sumatra, and Lhasa in East Gondwana.

Enantioselective C(sp3)–C(sp3) coupling substantially impacts organic synthesis but remains challenging. Cobalt has played an important role in the development of homogeneous organometallic catalysis, but there are few examples of its use in asymmetric cross-coupling. Here we report a cobalt-catalysed enantioselective C(sp3)–C(sp3) coupling reaction, namely, alkene hydroalkylation, to access chiral fluoroalkanes. This reaction represents a catalyst-controlled enantioselective coupling mode in which a tailor-made auxiliary is unnecessary; via this reaction, an aliphatic C–F stereogenic centre can be introduced at the desired position in an alkyl chain. Enantioselective C(sp3)–C(sp3) coupling plays an important role in organic synthesis, but limitations remain. Now, cobalt-catalysed enantioselective C(sp3)–C(sp3) coupling between achiral fluoroalkenes and alkyl halides enables the streamlined and auxiliary-free synthesis of chiral fluoroalkanes.

GRO J1008-57, as a Be/X-ray transient pulsar, is considered to have the highest magnetic field in known neutron star X-ray binary systems. Observational data of the X-ray outbursts in GRO J1008-57 from 2017 to 2020 were collected by the Insight-HXMT satellite. In this work, the spin period of the neutron star in GRO J1008-57 was determined to be about 93.28 seconds in August 2017, 93.22 seconds in February 2018, 93.25 seconds in June 2019 and 93.14 seconds in June 2020. GRO J1008-57 evolved in the spin-up process with a mean rate of − ( 2.10 ± 0.05 ) × 10−4 s/d from 2009 – 2018, and turned into a spin down process with a rate of ( 6.7 ± 0.6 ) × 10−5 s/d from Feb 2018 to June 2019. During the type II outburst of 2020, GRO J1008-57 had the spin-up torque again. During the torque reversals, the pulse profiles and continuum X-ray spectra did not change significantly, and the cyclotron resonant scattering feature around 80 keV was only detected during the outbursts in 2017 and 2020. Based on the observed mean spin-up rate, we estimated the inner accretion disk radius in GRO J1008-57 (about 1 - 2 times of the Alfven radius) by comparing different accretion torque models of magnetic neutron stars. During the spin-down process, the magnetic torque should dominate over the matter accreting inflow torque, and we constrained the surface dipole magnetic field B ≥ 6 × 10 12 G for the neutron star in GRO J1008-57, which is consistent with the magnetic field strength obtained by cyclotron line centroid energy.

Regiodivergent alkene functionalization that produces either regioisomer starting from the same raw materials is desirable. Herein, we report a nickel-catalyzed switchable site-selective alkene hydroalkylation. The selection of reaction temperatures leads to protocols that provide regiodivergent hydroalkylated products starting from a single alkene substrate. This protocol allows the convenient synthesis of α- and β-branched protected amines, both of which are important to the fields of pharmaceutical chemistry and biochemistry. In addition, enantioenriched β-branched alkylamines can be accessed in a catalytic asymmetric variant. Preliminary mechanistic studies indicate that the formation of a more stable nickelacycle provides the driving force of migration. The thermodynamic and kinetic properties of different reduction elimination intermediates are responsible for the switchable site-selectivity.

Focusing on data imbalance and intraclass variation, an improved pedestrian detection with a cascade of complex peer AdaBoost classifiers is proposed. The series of the AdaBoost classifiers are learned greedily, along with negative example mining. The complexity of classifiers in the cascade is not limited, so more negative examples are used for training. Furthermore, the cascade becomes an ensemble of strong peer classifiers, which treats intraclass variation. To locally train the AdaBoost classifiers with a high detection rate, a refining strategy is used to discard the hardest negative training examples rather than decreasing their thresholds. Using the aggregate channel feature (ACF), the method achieves miss rates of 35% and 14% on the Caltech pedestrian benchmark and Inria pedestrian dataset, respectively, which are lower than that of increasingly complex AdaBoost classifiers, i.e., 44% and 17%, respectively. Using deep features extracted by the region proposal network (RPN), the method achieves a miss rate of 10.06% on the Caltech pedestrian benchmark, which is also lower than 10.53% from the increasingly complex cascade. This study shows that the proposed method can use more negative examples to train the pedestrian detector. It outperforms the existing cascade of increasingly complex classifiers.

Titanium nitride alloy has triggered extensive interests for the actual application in aeronautics and astronautics, especially in the biological window serving as cancer therapy and tumor detection due to broad band absorption. However, developing a facile and reliable method for the manufacture of TiN films is still a propelled and demanding challenge. Here we present a one-step approach to obtain cubic-TiN films using plasma-enhanced chemical vapor deposition (PECVD) for the first time. Large-scale TiN films can be deposited on sophisticated substrate (e.g. flattened and curled shape) with controllable size by our PECVD approach. The chemical composition and structural analysis were conducted by X-ray diffraction, scanning electron microscope, transmission electron microscopy, and X-ray photoelectron spectroscopy. Furthermore, the TiN powders extracted from our films for photothermal effect demonstrated an excellent photothermal conversion efficiency of 47.9% under 808 nm irradiation. Our study not only offers a facile PECVD route to realize the TiN films on sophisticated substrates, but also provides a promising candidate for photothermal therapy in the future.

A new black hole X-ray binary (BHXRB) MAXI J1535-571 was discovered by MAXI during its outburst in 2017. Using observations taken by the first Chinese X-ray satellite, the Hard X-ray Modulation Telescope (dubbed as Insight-HXMT), we perform a joint spectral analysis (2-150 keV) in both energy and time domains. The energy spectra provide the essential input for probing the intrinsic Quasi-Periodic Oscillation (QPO) fractional rms spectra (FRS). Our results show that during the intermediate state, the energy spectra are in general consistent with those reported by Swift/XRT and NuSTAR. However, the QPO FRS become harder and the FRS residuals may suggest the presence of either an additional power-law component in the energy spectrum or a turn-over in the intrinsic QPO FRS at high energies.

We study the 2018 outburst of Aql X-1 via the monitor of all sky X-ray image (MAXI) data. We show that the outburst starting in February 2018 is a member of short-low class in the frame of outburst duration and the peak count rate although the outburst morphology is slightly different from the other fast-rise-exponential-decay (FRED) type outbursts with a milder rising stage. We study the partial accretion in the weak propeller stage of Aql X-1 via the MAXI data of the 2018 outburst. We report on the spectral analysis of 3 observations of Aquila X-1 obtained by Insight – hard X-ray modulation telescope (Insight-HXMT) during the late decay stage of the 2018 outburst. We discuss that the data taken by Insight-HXMT is just after the transition to the weak propeller stage. Our analysis shows the necessity of a comptonization component to take into account the existence of an electron cloud resulting photons partly up-scattered.

For the development of high-performance gas sensors, ultrafast response and high selectivity are critical requirements for many practical applications. An alternative strategy is to employ hierarchical nanostructured materials in gas sensors. In this work, we report newly synthesized TiO2 hexagonal nanosheets with a hierarchical porous structure, which demonstrate an ultrafast gas response and high selectivity toward acetone vapor for the first time. A simple one-step annealing process to prepare hierarchical TiO2 nanosheets derived from layered TiSe2 nanosheet templates is reported. The hierarchical structure interlaced with anatase TiO2 nanosheets showed an open porous characteristic. The average pore size was about 20 nm examined using a high-resolution TEM. The gas sensing properties toward acetone vapor of the novel hierarchical structured TiO2 nanosheets were characterized in detail including optimal operation temperature, sensitivity, selectivity, response/recovery time, and long-term stability. The gas sensing response and recovery times were 0.75 s and 0.5 s, respectively. We attribute these superior response properties to its unique hierarchical pore structure with a high specific surface area. The results show great potential for acetone vapor detection, particularly in dynamic ultrafast monitoring by using the synthesized hierarchical structured TiO2 nanosheets.

Objective To establish the normal parameters of fetal lung development at different gestational ages and to study their correlation with gestational age, thereby providing clinicians with a noninvasive method for assessing fetal lung maturity. Methods Two hundred eight cases with pregnancy of 22 to 39 weeks plus 6 days were divided into 18 groups according to gestational age. Ultrasound Doppler was used to measure the relevant parameters of fetal pulmonary development, including right pulmonary left and right diameter, right pulmonary upper and lower diameter, right pulmonary anterior and posterior diameter, right pulmonary area, thoracic area, inner diameter of fetal main pulmonary artery, and Doppler velocity curve parameters of main pulmonary artery: systolic acceleration time (AT), ejection time (ET), AT/ET. Results This study establishes normal parameters of lung development at different gestational weeks, draws scatter plots, correlation, and regression analysis of fetal main pulmonary artery AT, ET, AT/ET, and gestational weeks; selects the optimal equation; and analyzes the correlation among right pulmonary left and right diameter, right pulmonary upper and lower diameter, right pulmonary anterior and posterior diameter, right lung diameter, right lung area, thoracic area, and gestational weeks; and draw growth curve. The diameter of main pulmonary artery, AT, and AT/ET increased with the increase of gestational age and were positively correlated with gestational age (r = 0.948, 0.875, 0.810; P = 0.012). Ejection time had no correlation with gestational weeks. There were significant differences in the diameter of main pulmonary artery, AT, AT/ET between different gestational weeks (F = 240.67, 41.137, 23.067; P = 0.024); left and right diameter of right lung, anterior and posterior diameter of right lung, upper and lower diameter of right lung, chest area and right lung area were positively correlated with gestational weeks, and there were significant differences between different gestational weeks (F = 190.85, 105.74, 34.97, 172.33, 35.33, P = 0.018). Conclusions Ultrasound Doppler can be used as a noninvasive detecting equipment to evaluate the growth of fetal lung, thus providing a basis for the evaluation of fetal lung maturity.

As a major limitation for power scaling of high power narrow linewidth fiber master oscillator power amplifiers (MOPAs), Stimulated Brillouin Scattering (SBS) induced self-pulsing in polarization maintaining (PM) fiber amplifiers is well characterized and analyzed in this paper by comparing different white noise signal (WNS) phase-modulated modes in experiments. It is found that the self-pulsing effect is not observed in the PM-amplifier with single-frequency laser seed injection, and cascaded WNS modulation provides superior self-pulsing suppression than single WNS modulation with similar output linewidth. Moreover, the experimental results indicate that the self-pulsing threshold can hardly be predicted only by the output linewidth or the defined SBS threshold in a WNS phase modulated fiber amplifier system. As self-pulsing is originated from the spectral spikes in WNS modulated system, we theoretically analyzed characteristics of these spikes in different phase-modulation modes. It indicates the spectral peak intensity can be reduced by cascaded modulation, for which self-pulsing can be suppressed. The theoretical predictions agree well with the experimental results. At the same time, in order to suppress the mode instability effect, a plum blossom shaped bending mode selection device is used in this high-power narrow linewidth fiber amplifier system. Finally, a 32 GHz cascaded WNSs modulated, over than 2.5 kW linearly polarized all-fiber amplifier with a slope efficiency of 86.7% is demonstrated. The polarization extinction ratio (PER) is measured larger than 14 dB and the beam quality factor M2 maintains lower than 1.3 in the power scaling process.

An approach for reliable and predictable carbon-carbon or carbon-heteroatom bond formation that produces either regioisomer starting from the same raw materials, also known as a regiodivergent methodology, is highly desirable. Altering the chemical reaction variables, including catalysts, ligands, solvents, or other additives, were the predominant strategy for the implementation of regiodivergent features in metal-catalysed organic synthesis. The achievement of switchable selectivity using quickly and conveniently controlled physical variables constitutes a desirable goal with an intriguing method of attainment. Herein, we report our discovery that temperature-regulated switchable site-selectivity can be achieved in alkene (migratory) functionalization. Judicious selection of reaction temperatures, one of the most easily changed variables, led to protocols that provide the regiodivergent alkylation products starting from a single alkene substrate. This protocol allows for the convenient synthesis of α- and β-branched protected amines, both of which are substantially important to the pharmaceutical chemistry and biochemistry fields. In addition, enantioenriched β-branched alkyl amines could be accessed in a catalytic asymmetric variant manner. This work may inspire more research interests in metal-catalysed regiodivergent reaction discovery using easily changed physical variables.