55 research outputs found

    The Effects of Firm Relational Capital on Export Performance: The Moderating Effects of Technological Turbulence

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    Recent studies recognize that relational capital helps manufacturing firms in Global value chains (GVCs) enhance their competitiveness in global markets. However, prior research does not provide a conclusive account of the impact of relational capital on export performance, particularly in developing countries. Drawing on a learning-based perspective and contingency approach, this study fills these gaps by linking relational capital and firm performance with a focus on manufacturing firms in developing countries that participate in GVCs. Specifically, we propose that the relational capital of these firms will have a stronger positive impact on their export performance when the technological turbulence is lower, and vice versa. Overall, this research extends the literature on knowledge transfer, interfirm relational capital, and business performance in a developing-country context

    Progress of regional oceanography study associated with western boundary current in the South China Sea

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    Recent progress of physical oceanography in the South China Sea (SCS) associated with the western boundary current (WBC) and eddies is reviewed in this paper. It includes Argo observations of the WBC, eddy detection in the WBC based on satellite images, cross-continental shelf exchange in the WBC, eddy-current interaction, interannual variability of the WBC, air-sea interaction, the SCS throughflow (SCSTF), among others. The WBC in the SCS is strong, and its structure, variability and dynamic processes on seasonal and interannual time scales are yet to be fully understood. In this paper, we summarize progresses on the variability of the WBC, eddy-current interaction, air-sea interaction, and the SCSTF achieved in the past few years. Firstly, using the drifting buoy observations, we point out that the WBC becomes stronger and narrower after it reaches the central Vietnam coast. The pos-sible mechanisms influencing the ocean circulation in the northern SCS are discussed, and the dynamic mechanisms that induce the countercurrent in the region of northern branch of WBC in winter are also studied quantitatively using momentum balance. The geostropic component of the WBC was diagnosed using the ship observation along 18°N, and we found that the WBC changed significantly on interannual time scale. Secondly, using the ship observations, two anti-cyclonic eddies in the winter of 2003/2004 in the northern SCS, and three anti-cyclonic eddies in the summer of 2007 along 18°N were studied. The results show that the two anti-cyclonic eddies can propagate southwestward along the continental shelf at the speed of first Rossby wave (~0.1 m s1) in winter, and the interaction between the three anti-cyclonic eddies in summer and the WBC in the SCS is preliminarily revealed. Eddies on the continental shelf of northern SCS propagated southeastward with a maximum speed of 0.09 m s-1, and those to the east of Vietnam coast had the largest kinetic energy, both of which imply strong interaction between eddy activity and WBC in the SCS. Thirdly, strong intraseasonal variability (ISV) of sea surface temperature (SST) near the WBC regions was found, and the ISV signal of SST in winter weakens the ISV signal of latent heat flux by 20%. Fourthly, the long-term change of SCSTF volume transport and its connection with the ocean circulation in the Pacific were discussed

    Multi-scale convolutional recurrent neural network for psychiatric disorder identification in resting-state EEG

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    BackgroundAccurate classification based on affordable objective neuroimaging biomarkers are important steps toward designing individualized treatment.MethodsIn this work, we investigated a deep learning classification model, multi-scale convolutional recurrent neural network (MCRNN), to explore psychiatric disorder-related biomarkers by leveraging the spatiotemporal information of resting-state EEG (rsEEG) using a multiple psychiatric disorder database containing 327 individuals diagnosed with schizophrenia, bipolar, major depressive disorders, and healthy controls. All subjects were mapped to a shared low-dimensional subspace for intuitively interpreting the inter-relationship and separation of psychiatric disorders.ResultsPsychiatric disorders were identified using rsEEG with high accuracy ranged from 78.6 to 91.3% in patient vs. controls two-class classification, and 68.2% in four-class classification. The control-to-schizophrenia trajectory interpretated by the model was consistent with the disease severity in clinical observation.ConclusionThe MsRNN demonstrated a capability in extracting discriminative rsEEG biomarkers for psychiatric disorder classification, indicating its potential to facilitate our understanding of psychiatric disorders and monitoring interventions

    Pharmacokinetic evaluation of the PNC disassembler metarrestin in wild-type and Pdx1-Cre;LSL-KrasG12D/+;Tp53R172H/+ (KPC) mice, a genetically engineered model of pancreatic cancer

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    This work is licensed under a Creative Commons Attribution 4.0 International License.Purpose Metarrestin is a first-in-class small molecule clinical candidate capable of disrupting the perinucleolar compartment, a subnuclear structure unique to metastatic cancer cells. This study aims to define the pharmacokinetic (PK) profile of metarrestin and the pharmacokinetic/pharmacodynamic relationship of metarrestin-regulated markers. Methods PK studies included the administration of single or multiple dose of metarrestin at 3, 10, or 25 mg/kg via intravenous (IV) injection, gavage (PO) or with chow to wild-type C57BL/6 mice and KPC mice bearing autochthonous pancreatic tumors. Metarrestin concentrations were analyzed by UPLC–MS/MS. Pharmacodynamic assays included mRNA expression profiling by RNA-seq and qRT-PCR for KPC mice. Results Metarrestin had a moderate plasma clearance of 48 mL/min/kg and a large volume of distribution of 17 L/kg at 3 mg/kg IV in C57BL/6 mice. The oral bioavailability after single-dose (SD) treatment was > 80%. In KPC mice treated with SD 25 mg/kg PO, plasma AUC0–∞ of 14400 ng h/mL, Cmax of 810 ng/mL and half-life (t1/2) of 8.5 h were observed. At 24 h after SD of 25 mg/kg PO, the intratumor concentration of metarrestin was high with a mean value of 6.2 ”g/g tissue (or 13 ”M), well above the cell-based IC50 of 0.4 ”M. At multiple dose (MD) 25 mg/kg/day PO in KPC mice, mean tissue/plasma AUC0–24h ratio for tumor, spleen and liver was 37, 30 and 31, respectively. There was a good linear relationship of dosage to AUC0–24h and C24h. AUC0–24h MD to AUC0–24h SD ratios ranged from two for liver to five for tumor indicating additional accumulation in tumors. Dose-dependent normalization of FOXA1 and FOXO6 mRNA expression was observed in KPC tumors. Conclusions Metarrestin is an effective therapeutic candidate with a favorable PK profile achieving excellent intratumor tissue levels in a disease with known poor drug delivery.Intramural Research Program (IRP) of the NIHNational Cancer InstituteCenter for Cancer Research (ZIA BC 011267

    Discovery and Optimization of Pyrrolopyrimidine Derivatives as Selective Disruptors of the Perinucleolar Compartment, a Marker of Tumor Progression toward Metastasis

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    This document is the Accepted Manuscript version of a Published Work that appeared in final form in Journal of Medicinal Chemistry, Copyright © 2022 American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/acs.jmedchem.2c00204.The perinucleolar compartment (PNC) is a dynamic subnuclear body found at the periphery of the nucleolus. The PNC is enriched with RNA transcripts and RNA-binding proteins, reflecting different states of genome organization. PNC prevalence positively correlates with cancer progression and metastatic capacity, making it a useful marker for metastatic cancer progression. A high-throughput, high-content assay was developed to identify novel small molecules that selectively reduce PNC prevalence in cancer cells. We identified and further optimized a pyrrolopyrimidine series able to reduce PNC prevalence in PC3M cancer cells at submicromolar concentrations without affecting cell viability. Structure–activity relationship exploration of the structural elements necessary for activity resulted in the discovery of several potent compounds. Analysis of in vitro drug-like properties led to the discovery of the bioavailable analogue, metarrestin, which has shown potent antimetastatic activity with improved survival in rodent models and is currently being evaluated in a first-in-human phase 1 clinical trial

    Development of high temperature acoustic emission sensing system using fiber Bragg grating

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    Abstract In some applications in structural health monitoring (SHM), the acoustic emission (AE) detection technology is used in the high temperature environment. In this paper, a high-temperature-resistant AE sensing system is developed based on the fiber Bragg grating (FBG) sensor. A novel high temperature FBG AE sensor is designed with a high signal-to-noise ratio (SNR) compared with the traditional FBG AE sensor. The output responses of the designed sensors with different sensing fiber lengths also are investigated both theoretically and experimentally. Excellent AE detection results are obtained using the proposed FBG AE sensing system over a temperature range from 25 ℃ to 200 ℃. The experimental results indicate that this FBG AE sensing system can well meet the application requirement in AE detecting areas at high temperature

    Post combustion CO2 capture in power plant using low temperature steam upgraded by double absorption heat transformer

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    In CO2 capture retrofit unit of existing coal-fired power plants, energy level mismatch between extraction steam from turbines and CO2 regeneration process always results in large exergy destruction and low thermal efficiency. Thus, a new CO2 capture system driven by double absorption heat transformer is proposed. Through the absorption heat transformer, low-temperature steam is upgraded into a higher energy level to match the temperature of CO2 regeneration. Also, flue gas heat is partly recovered to preheat the circulating water from CO2 capture process to further decrease system energy penalty. Aspen Plus 11.0 is used to simulate the system and parameters of key processes are validated by experimental values. It is shown that with 90% CO2 capture, the thermal efficiency of the power plant with proposed CO2 capture system is enhanced by 1.25 percentage points compared with traditional method. And the efficiency enhancement of the proposed system has a trend of increase first and then decrease with CO2 capture rate growth. For a 350 MW coal-fired power plant, the optimum CO2 capture rate is 53.65% and the corresponding efficiency enhancement is 2.06 percentage points. Exergy analysis shows that the exergy destruction in CO2 separation and steam condensation process can decrease by 49.5% in the proposed system, and thereby the exergy efficiency is 1.85 percentage points higher than the conventional method. Furthermore, the cost of CO2 avoided and cost of electricity of the proposed system will be reduced by 10.7 /t−CO2and1.9/t-CO2 and 1.9 /MW h, respectively

    Roles of interface engineering in performance optimization of skutterudite‐based thermoelectric materials

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    Abstract Interface engineering has prevailed in the thermoelectric field for decades, and related performance has achieved great progress. Therefore, an in‐depth understanding of the impacts of the interface effect on the thermoelectric transport parameters is of vital importance. In this paper, taking skutterudite‐based thermoelectric materials as typical examples, the formation mechanism and preparation process of various interface types, including 1D dislocations, 2D grain refinement, 3D nanocomposites, and micro‐nanopores, are briefly summarized. In addition, we also systemically highlight recently striking achievements related to interfacial design to reveal the distinctive effect of each interface structure on the transport behavior of carriers and phonons. Finally, existing challenges in the thermoelectric performance optimization achieved by interface engineering are pointed out, and an outlook for further thermoelectric research is presented
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