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A new and expedient photocatalytic protocol for the construction of quinolin-2(1H)-ones via Markovnikov-type sulfonylation/6-endo-trig cyclization/selective C(O)–CF3 bond cleavage starting from N-alkyl-N-(2-ethynylphenyl)-2,2,2-trifluoroacetamides and sulfinic acids has been developed. It is as an unprecedented protocol for the preparation of 4-sulfonylquinoline-2(1H)-ones with high efficiency, mild reaction conditions, acceptable yields and a wide range of substrates. [ABSTRACT FROM AUTHOR]

From a theoretical investigation of the sediment concentration distribution in sediment-laden flows, a relationship between the profile of sediment concentration and the intensity of vertical fluctuation of particles was established and indirectly verified using experimental data obtained in a vertical rectangular duct flow. It is shown that sediment suspension and the profile of sediment concentration are significantly influenced by the particle fluctuation. This leads to a new explanation for the mechanism of two patterns of sediment concentration profiles. DOI: 10.1061/(ASCE)0733-9399(2007)133:6(601) CE Database subject headings: Sediment concentration; Turbulent diffusion; Sediment transport.

Sorafenib was the first systemic therapy approved by the Food and Drug Administration to treat advanced hepatocellular carcinoma (HCC). However, sorafenib therapy is frequently accompanied by drug resistance. We aimed to explore the mechanisms of sorafenib resistance and provide feasible solutions to increase the response to sorafenib in patients with advanced HCC. The expression profile of discoidin domain receptor 2 (DDR2) in HCC tissues and cells was detected using quantitative real‐time PCR (qPCR) and western blotting assays. The effects of DDR2 on sorafenib resistance were examined using 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide, colony formation, TdT‐mediated dUTP nick end labeling, and flow cytometry assays. The effect of DDR2 on the nuclear factor kappa B (NF‐κB) signaling pathway was evaluated by luciferase reporter, immunofluorescence, qPCR and flow cytometry assays. We demonstrated that DDR2 expression was dramatically upregulated in sorafenib‐resistant HCC tissues relative to sensitive tissues. Downregulation of DDR2 sensitized HCC cell lines to sorafenib cytotoxicity. Further analysis showed that DDR2 could increase the nuclear location of REL proto‐oncogene, a NF‐κB subunit, to mediate NF‐κB signaling. Blocking NF‐κB signaling using the NF‐κB signaling inhibitor, bardoxolone methyl, increased the response of HCC cells to sorafenib. Further analysis showed that DNA amplification of DDR2 is an important mechanism leading to DDR2 overexpression in HCC. Our results demonstrated that DDR2 is a potential therapeutic target in patients with HCC, and targeting DDR2 represents a promising approach to increase sorafenib sensitivity in patients with HCC. [ABSTRACT FROM AUTHOR]

In view of the problems surrounding the research and application of carbon materials, the process of choosing a carbon source is still not perfect. There are few studies concentrating on the establishment of structure–property relationships based on the choice of carbon source. In this regard, our present work contributes the design of an organic precursor that is expected to allow the controllable construction of the carbon material, thus regulating its functionality. A highly π-conjugated Schiff base moiety with alternating imine groups (C＝N) and benzene rings was incorporated into the main chain of a mesoporous polymer. For comparison, a bisphenol-A-type moiety was employed in the main chain of another mesoporous polymer. Using the mesoporous polymers as organic precursors for porous carbon sources, the formation of mesoporous carbon can be attributed to the presence of the highly π-conjugated Schiff base moiety due to its self-supporting effect and char-forming ability, which are absent in the bisphenol-A-type moiety. However, we are not only concerned with the contribution from the chemical structure of the designed precursor to the controllable construction of mesoporous carbon, but also concerned with its regulation of the electrochemical performance of the resulting material. Through characterization using cyclic voltammetry (CV), galvanostatic charge–discharge profiles, and electrochemical impedance spectroscopy (EIS), this kind of mesoporous carbon has been found to have excellent charge storage and transportation abilities and shows potential for application in the electrodes of electrochemical capacitors. [ABSTRACT FROM AUTHOR]

Background The outbreak of coronavirus disease 2019 (COVID-19) has spread worldwide and continues to threaten peoples' health as well as put pressure on the accessibility of medical systems. Early prediction of survival of hospitalized patients will help in the clinical management of COVID-19, but a prediction model that is reliable and valid is still lacking. Methods We retrospectively enrolled 628 confirmed cases of COVID-19 using positive RT-PCR tests for SARS-CoV-2 in Tongji Hospital, Wuhan, China. These patients were randomly grouped into a training (60%) and a validation (40%) cohort. In the training cohort, LASSO regression analysis and multivariate Cox regression analysis were utilized to identify prognostic factors for in-hospital survival of patients with COVID-19. A nomogram based on the 3 variables was built for clinical use. AUCs, concordance indexes (C-index), and calibration curves were used to evaluate the efficiency of the nomogram in both training and validation cohorts. Results Hypertension, higher neutrophil-to-lymphocyte ratio, and increased NT-proBNP values were found to be significantly associated with poorer prognosis in hospitalized patients with COVID-19. The 3 predictors were further used to build a prediction nomogram. The C-indexes of the nomogram in the training and validation cohorts were 0.901 and 0.892, respectively. The AUC in the training cohort was 0.922 for 14-day and 0.919 for 21-day probability of in-hospital survival, while in the validation cohort this was 0.922 and 0.881, respectively. Moreover, the calibration curve for 14- and 21-day survival also showed high coherence between the predicted and actual probability of survival. Conclusions We built a predictive model and constructed a nomogram for predicting in-hospital survival of patients with COVID-19. This model has good performance and might be utilized clinically in management of COVID-19. [ABSTRACT FROM AUTHOR]

Mixed fluid–particle flows are commonly found in nature and exhibit complex particle–particle and particle–fluid interactions. In this paper, a typical small-scale case of immersed granular collapse under the viscous regime is numerically investigated using computational fluid dynamics coupled with the discrete element method (CFD-DEM), which provide particle-scale information of the collapse. The input parameters for the coupled CFD-DEM model are carefully calibrated from experimental results, and the simulation results achieve good agreement with the experiments in terms of the front evolution and final deposition. The collapse processes for different aspect ratios exhibit similarities and propagate in a three-stage mode that includes acceleration, steady propagation, and deceleration. The propagation velocity, runout distance, and the energy evolution of both fluid and particles are presented. The final runout is linearly proportional to the densimetric Froude number in our high-column cases. The transition of particles' motion from vertical to horizontal and the drag of the fluid are found to be responsible for the constant velocity in the steady propagation stage. We also show that a small energy bump during the initial stage is the result of particle destabilization and rearrangement. [ABSTRACT FROM AUTHOR]

The evolution of energy in subaerial and subaqueous granular column collapses is studied. Employing the refractive index matching method and planar laser-induced fluorescence technique, we obtain granular and liquid images simultaneously in a single experiment of subaqueous flow. Particle image velocimetry and particle tracking velocimetry are used to process the data for the fluid and granular phase. We find stepwise decreases in the total kinetic energy of the granular material. The stage of rapidly falling energy corresponds to large transverse changes in the direction of the massive granular particles. Moreover, in this stage, a major fraction of the granular kinetic energy transferred from the granular potential energy is lost or transferred. Interestingly, compared with dry granular flow, the existence of an ambient liquid seems to reduce the total dissipated energy, which may be the reason why previous studies observed similar granular runout distances in subaqueous and dry granular collapses. [ABSTRACT FROM AUTHOR]

This paper investigates the state estimation problem for linear time-invariant systems where sensors and controllers are geographically separated and connected via stationary memoryless uncertain digital communication channels with the information rate limitation. Such channels introduce data packet dropout, stochastic time delay, and data packet reordering. In the TCP/IP model, the transport layer provides a reliable service on top of an unreliable communication channel. However, the performance of such systems is still affected by packet reordering and stochastic time delay. In particular, we present an optimal encoding and decoding scheme to guarantee observability by employing the minimum information rate, and derive a necessary and sufficient condition on the delay distribution and information rate for observability. Illustrative examples are given to demonstrate the effectiveness of the proposed scheme. [ABSTRACT FROM AUTHOR]

Background: Resting-state functional magnetic resonance imaging (fMRI) studies have uncovered the disruptions of functional brain networks in primary insomnia (PI) patients. However, the etiology and pathogenesis underlying this disorder remains ambiguous, and the insomnia related symptoms are influenced by a complex network organization in the brain. The purpose of this study was to explore the abnormal intrinsic functional hubs in PI patients using a voxel-wise degree centrality (DC) analysis and seed-based functional connectivity (FC) approach. Methods: A total of 26 PI patients and 28 healthy controls were enrolled, and they underwent resting-state fMRI. Degree centrality was measured across the whole brain, and group differences in DC were compared. The peak points, which significantly altered DC between the two groups, were defined as the seed regions and were further used to calculate FC of the whole brain. Later, correlation analyses were performed between the changes in brain function and clinical features. Results: Primary insomnia patients showed DC values lower than healthy controls in the left inferior frontal gyrus (IFG) and middle temporal gyrus (MTG) and showed a higher DC value in the right precuneus. The seed-based analyses demonstrated decreased FC between the left MTG and the left posterior cingulate cortex (PCC), and decreased FC was observed between the right precuneus and the right lateral occipital cortex. Reduced DC in the left IFG and decreased FC in the left PCC were positively correlated with the Pittsburgh sleep quality index and the insomnia severity index. Conclusions: This study revealed that PI patients exhibited abnormal intrinsic functional hubs in the left IFG, MTG, and the right precuneus, as well as abnormal seed-based FC in these hubs. These results contribute to better understanding of how brain function influences the symptoms of PI. [ABSTRACT FROM AUTHOR]

The Mesozoic granitoids in the Dabie Orogen are of particular geological interest as indicators for Mesozoic lithospheric evolution because of their close association with porphyry Mo mineralization. Here, we present a study using petrogeochemistry data to constrain the petrogenesis of the Xiaofan granites in the Dabie Mo mineralization belt (DMB), Henan Province, China. Field investigations show that the Xiaofan pluton mainly consists of porphyritic granite. The Xiaofan granites have high SiO2 contents of 74.29 wt%-76.07 wt% (average: 75.18 wt%), Al2O3 contents of 11.66 wt%-12.83 wt% (average: 12.13 wt%), and K2O contents of 5.37 wt%-7.90 wt% (average: 6.86 wt%) and low MgO (0.06 wt%-0.16 wt%), TiO2 (0.09 wt%-0.10 wt%), and P2O5 (0.047 wt%-0.103 wt%) contents. They are enriched in Rb, U, K and Hf but depleted in Ba, Nb, Ta, Sr and Ti. By geochemical and mineralogical features, we propose that the Xiaofan granites belong to A-type type granite and dominantly sourced from the crust. The granites from the Xiaofan Mo deposit may have formed in a post-collision extensional setting. [ABSTRACT FROM AUTHOR]

Background: Insomnia is one of the main symptom correlates of major depressive disorder (MDD), but the neural mechanisms underlying the multifaceted interplay between insomnia and depression are not fully understood. Materials and methods: Patients with MDD and high insomnia (MDD-HI, n = 24), patients with MDD and low insomnia (MDD-LI, n = 37), and healthy controls (HCs, n = 51) were recruited to participate in the present study. The amplitude of low-frequency fluctuations (ALFF) during the resting state were compared among the three groups. results: We observed ALFF differences between the three groups in the right inferior frontal gyrus/anterior insula (IFG/AI), right middle temporal gyrus, left calcarine, and bilateral dorsolateral prefrontal cortex (dlPFC). Further region of interest (ROI) comparisons showed that the increases in the right IFG/AI reflected an abnormality specific to insomnia in MDD, while increases in the bilateral dlPFC reflected an abnormality specific to MDD generally. Increased ALFF in the right IFG/AI was also found to be correlated with sleep disturbance scores when regressing out the influence of the severity of anxiety and depression. conclusion: Our findings suggest that increased resting state ALLF in IFG/AI may be specifically related to hyperarousal state of insomnia in patients with MDD, independently of the effects of anxiety and depression. Background: Insomnia is one of the main symptom correlates of major depressive disorder (MDD), but the neural mechanisms underlying the multifaceted interplay between insomnia and depression are not fully understood. Materials and methods: Patients with MDD and high insomnia (MDD-HI, n = 24), patients with MDD and low insomnia (MDD-LI, n = 37), and healthy controls (HCs, n = 51) were recruited to participate in the present study. The amplitude of low-frequency fluctuations (ALFF) during the resting state were compared among the three groups. results: We observed ALFF differences between the three groups in the right inferior frontal gyrus/anterior insula (IFG/AI), right middle temporal gyrus, left calcarine, and bilateral dorsolateral prefrontal cortex (dlPFC). Further region of interest (ROI) comparisons showed that the increases in the right IFG/AI reflected an abnormality specific to insomnia in MDD, while increases in the bilateral dlPFC reflected an abnormality specific to MDD generally. Increased ALFF in the right IFG/AI was also found to be correlated with sleep disturbance scores when regressing out the influence of the severity of anxiety and depression. conclusion: Our findings suggest that increased resting state ALLF in IFG/AI may be specifically related to hyperarousal state of insomnia in patients with MDD, independently of the effects of anxiety and depression. [ABSTRACT FROM AUTHOR]

Insomnia is characterized by sensory hypersensitivity and cognitive impairments. Recent work has identified the insula as a central brain region involved in both bottom-up gating of sensory information and top-down cognitive control. However, the specific relationships between insular subregion connectivity and emotional and cognitive functions remain unclear. In this study, resting-state functional magnetic resonance imaging data were obtained from 25 healthy participants with sleep complaints (HPS) and 25 age-, gender- and educational level-matched healthy participants without insomnia complaints (HP). We performed insular subregion (ventral anterior, dorsal anterior and posterior) functional connectivity (FC) analyses, and cognitive function was measured with several validated test procedures (e.g., the Wisconsin Card Sorting Test [WCST], Continuous Performance Test [CPT] and Trail making Test [TMT]). There were no significant differences between the two groups for WCST, CPT and TMT scores. The HPS group showed enhanced connectivity from the right posterior insula (R-PI) to the left postcentral gyrus (L-postCG) compared to HP group. WCST random errors (RE), sleep disturbance scores and HAMA scores correlated with this connectivity measurement in both HP and HPS groups. Our results provide direct evidence that the posterior insula (PI) synchronizes with sensorimotor areas to detect homeostatic changes and suggest that alteration of the latter is related to executive dysfunction in subjects with insomnia. [ABSTRACT FROM AUTHOR]

The Mesozoic granitoids in the Dabie Orogen are of particular geological interest as indicators for Mesozoic lithospheric evolution and because of their close association with porphyry Mo mineralization. Here, we present a study using zircon laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) U–Pb dating, petrogeochemistry, and Hf isotopic data to constrain the timing of the magmatism and petrogenesis of the Xinxian granites in the Dabie Mo mineralization belt (DMB), Henan Province, China. Field investigations combined with previously published data show that the Xinxian pluton mainly consists of four phases. Zircon LA-ICP-MS U–Pb dating yielded ages from 153.4 ± 1.1 Ma for Phase 1 to 146.4 ± 1.6 Ma for Phase 2, 131.6 ± 1.8 Ma for Phase 3, and 125.5 ± 1.5 Ma for Phase 4. The Xinxian granites have high SiO2contents of 74.94–78.70 wt.% (average: 76.63 wt.%), Al2O3contents of 11.59–13.68 wt.% (average: 13.01 wt.%), and K2O contents of 3.85–4.86 wt.% (average: 4.36 wt.%) with Na2O/K2O ratios of 0.78–1.03 (average: 0.92) and low MgO (0.04–0.15 wt.%), TiO2(0.03–0.13 wt.%), and P2O5(0.006–0.07 wt.%) contents. They are enriched in Rb, U, K, and Hf, but depleted in Ba, Nb, Ta, Sr, P, and Ti. The zirconεHf(t) values for Phases 1, 2, 3, and 4 vary as follows: from – 22.8 to – 20.3 withTDM2values from 2682 to 2869 Ma, from – 24.2 to – 21.2 withTDM2values from 2738 to 2925 Ma, from −24.5 to −21.5 withTDM2values from 2722 to 2915 Ma, and from −22.9 to −19.4 withTDM2values from 2421 to 2643 Ma, respectively. By integrating previous geological, geochronological, and geochemical data for the DMB, we propose that the Xinxian pluton was dominantly sourced from the crust. The granites were most likely derived from the partial melting of the Northern Dabie Complex (NDC) with some Yangtze lower crust and Southern Dabie Complex (SDC). The Xinxian pluton may have formed in a post-collision extensional setting. [ABSTRACT FROM AUTHOR]

This paper investigates state estimation for linear time-invariant systems where sensors and controllers are geographically separated and connected via a bandwidth-limited and errorless communication channel with the fixed data rate.All plant states are quantised, coded and converted together into a codeword in our quantisation and coding scheme.We present necessary and sufficient conditions on the fixed data rate for observability of such systems, and further develop the data-rate theorem. It is shown in our results that there exists a quantisation and coding scheme to ensure observability of the system if the fixed data rate is larger than the lower bound given, which is less conservative than the one in the literature. Furthermore, we also examine the role that the disturbances have on the state estimation problem in the case with data-rate limitations. Illustrative examples are given to demonstrate the effectiveness of the proposed method. [ABSTRACT FROM PUBLISHER]

Caffeoylquinic acids (CQAs) are main constituents in many herbal medicines with various biological and pharmacological effects. However, CQAs will degrade or isomerize when affected by temperature, pH, light, etc. In this study, high-performance liquid chromatography with photodiode array detection (HPLC-PDA) and high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) was utilized to study the stability and degradation of CQAs (three mono-acyl CQAs and four di-acyl CQAs) under various ordinary storage conditions (involving different temperatures, solvents, and light irradiation). The results indicated that the stability of CQAs was mainly affected by temperature and light irradiation, while solvents did not affect it in any obvious way under the conditions studied. Mono-acyl CQAs were generally much more stable than di-acyl CQAs under the same conditions. Meanwhile, the chemical structures of 30 degradation products were also characterized by HPLC-MSn, inferring that isomerization, methylation, and hydrolysis were three major degradation pathways. The result provides a meaningful clue for the storage conditions of CQAs standard substances and samples. [ABSTRACT FROM AUTHOR]