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With the advent of artificial intelligence (AI), more and more enterprises have begun developing AI to promote their own competitive advantage and increase their business value. In order to reveal the value-added results of AI implementation, this study adopts an event study methodology to capture the abnormal returns resulting from the announcement of AI implementation. Based on the empirical results of this study, in response to the announcement of AI implementation, we find significant positive abnormal returns on the event day. With respect to the grouping analysis, the results show significant differences in average cumulative abnormal returns between announcements with detailed information and those without detailed information. In addition, our findings present significant differences in average cumulative abnormal returns between IT-companies and non-IT companies on the event day. Ultimately, according to the content analysis, only one characteristic, the frequency of negative words, is modestly and negatively correlated with average cumulative abnormal returns.

Since late 2019, coronavirus disease 2019 (COVID-19) has led to a significant increase in the demand for medical resources. To publish data on face mask supplies, the Taiwanese government collaborated with program developers to construct a mask-supply information transitional platform (MITP). To comprehend the adoption of MITP, the study proposes a research model that integrates the health behavior model (HBM) and IS/IT continuance model for examining the factors affecting intention to use an MITP. Survey data collected from 524 respondents indicated that (1) intention to use an MITP is directly influenced by perceived threat of COVID-19 and beliefs toward using the MITP; (2) cues to action directly influence the perceived threat of COVID-19; and (3) perceived ease of use of MITP is a significant determinant of perceived usefulness of MITP. These results provide practical guidelines for health authorities and government to develop health information systems and strategies to control pandemics.

Searching for X-ray and gamma-ray bursts, including Gamma-ray bursts (GRBs), Soft Gamma-ray Repeaters (SGRs) and high energy transients associated with Gravitational wave (GW) events or Fast radio bursts (FRBs), is of great importance in the multi-messenger and multi-wavelength era. Although a coherent search based on the likelihood ratio and Gaussian statistics has been established and utilized in many studies, this Gaussian-based method could be problematic for weak and short bursts which usually have very few counts. To deal with all bursts including weak ones, here we propose the coherent search in Poisson statistics. We studied the difference between Poisson-based and Gaussian-based search methods by Monte Carlo simulations, and find that the Poisson-based search method has advantages compared to the Gaussian case especially for weak bursts. Our results show that, for very weak bursts with very low number of counts, the Poisson-based search can provide higher significance than the Gaussian-based search, and its likelihood ratio (for background fluctuation) still generally follows the chi2 distribution, making the significance estimation of searched bursts very convenient. Thus, we suggest that the coherent search based on Poisson likelihood ratio is more appropriate in the search for generic transients including very weak ones., Comment: 10 pages, 10 figures

Since FRB 200428 has been found to be associated with an X-ray burst from the Galactic magnetar SGR J1935+2154, it is interesting to explore whether the magnetar bursts also follow the similar active periodic behaviour as some repeating FRBs. Previous studies show that there is possible period of about 230 days in SGR J1935+2154 bursts. Here, we collected an updated burst sample from SGR J1935+2154, including all bursts reported by Fermi/GBM and GECAM till 2022 January. We also developed a targeted search pipeline to reveal more bursts from SGR J1935+2154 in the Fermi/GBM data from 2008 August to 2014 December (i.e. before the first burst detected by Swift/BAT). With this burst sample, we re-analysed the possible periodicity of SGR J1935+2154 bursts using the Period Folding and Lomb–Scargle Periodogram methods. Our results show that the periodicity ∼238 days reported in literature is probably fake and the observation effects may introduce false periods (i.e. 55 days) according to simulation tests. We find that, for the current burst sample, the most probable period is 126.88 ± 2.05 days, which could be interpreted as the precession of the magnetar. However, we note that the whole burst history is very complicated and difficult to be perfectly accommodated with any period reported thus far, therefore more monitoring observations of SGR J1935+2154 are required to test any periodicity hypothesis.

Figure S1-13 and Table S1,3

PDF file - 111 KB, Predicted binding pose of #220-324 with SHP2 phosphatase.

Table S2

PDF file - 111 KB, #220-324 inhibited SHP2-mediated cell signaling.

PDF file - 65 KB, Effect of Triton X-100 on the function of #220-324 in inhibiting SHP2 activity.

PDF file - 80KB, Identification of active compounds that inhibited the phosphatase activity of SHP2 with various efficiencies.

Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor (GECAM) is a dedicated mission, launched in December 2020, for gamma-ray transients, including gamma-ray bursts (GRBs) and soft gamma repeater (SGR) bursts in the multimessenger and multiwavelength astronomy era. Since GECAM consists of two independent spacecrafts (or say instruments), and the framework of data analysis for multiple spacecrafts is distinctive from that for only one spacecraft, which is the case for most GRB missions, we developed a dedicated pipeline called Energetic Transients Joint Analysis System for Multi-INstrument (ETJASMIN) for GECAM mission. This pipeline has been naturally extended to incorporate data from other gamma-ray instruments, including the operating missions, such as Insight-HXMT/HE, Fermi/GBM, Swift/BAT, INTEGRAL/SPI-ACS, Konus-Wind, and GRID, as well as the forthcoming missions, such as SVOM/GRM and HEBS. In this paper, we present this pipeline with a focus on the data analysis procedures, methodology, and results in terms of the localization, verification (classification), spectral, and temporal analyses of gamma-ray transients. We show that this pipeline could provide more accurate, reliable, and comprehensive results than that of individual spacecraft, which is beneficial for gamma-ray transients observation.

PDF file - 39K, Shp2 depletion causes premature PLK1 and Cyclin B1 degradation

PDF file - 27K, Shp2-depleted cells fail to sustain nocodazole-induced mitotic arrest

PDF file - 54K, Depletion of Shp2 results in lagging chromosomes during unperturbed (without nocodazole treatment) mitosis

PDF file - 27K, Shp2 depletion decreases taxol-induced mitotic arrest

PDF file - 77K

While mitochondria in different tissues have distinct preferences for energy sources, they are flexible in utilizing competing substrates for metabolism according to physiological and nutritional circumstances. However, the regulatory mechanisms and significance of metabolic flexibility are not completely understood. Here we report that the deletion ofPTPMT1,a mitochondria-based phosphatase, critically alters mitochondrial fuel selection – the utilization of pyruvate, a key mitochondrial substrate derived from glucose (the major simple carbohydrate), is inhibited, whereas the fatty acid utilization is enhanced.PTPMT1knockout does not impact the development of the skeletal muscle or heart. However, the metabolic inflexibility ultimately leads to muscular atrophy, heart failure, and sudden death. Mechanistic analyses reveal that the prolonged substrate shift from carbohydrates to lipids causes oxidative stress and mitochondrial destruction, which in turn results in marked accumulation of lipids and profound damage in the knockout muscle cells and cardiomyocytes. Interestingly,PTPMT1deletion from the liver or adipose tissue does not generate any local or systemic defects. These findings suggest that PTPMT1 plays an important role in maintaining mitochondrial flexibility and that their balanced utilization of carbohydrates and lipids is essential for both the skeletal muscle and the heart despite the two tissues having different preferred energy sources.

The first X-ray source catalog of Insight-HXMT Galactic Plane (|b, 43 pages, 26 figures, accepted for publication in ApJS

We have performed a spectral-timing analysis on the black hole X-ray binary MAXI J1535--571 during its 2017 outburst, with the aim of exploring the evolution of the inner accretion flow geometry. X-ray reverberation lags are observed in the hard-intermediate state (HIMS) and soft-intermediate state (SIMS) of the outburst. During the HIMS, the characteristic frequency of the reverberation lags $\nu_0$ (the frequency at which the soft lag turns to zero in the lag-frequency spectra) increases when the spectrum softens. This reflects a reduction of the spatial distance between the corona and accretion disc, when assuming the measured time lags are associated with the light travel time. We also find a strong correlation between $\nu_0$ and type-C Quasi Periodic Oscillation (QPO) centroid frequency $\nu_{QPO}$, which can be well explained by the Lense-Thirring (L-T) precession model under a truncated disk geometry. Despite the degeneracy in the spectral modellings, our results suggest that the accretion disc is largely truncated in the low hard state (LHS), and moves inward as the spectrum softens. Combine the spectral modelling results with the $\nu_0$ - $\nu_{QPO}$ evolution, we are inclined to believe that this source probably have a truncated disk geometry in the hard state.

On April 27, 2020, the soft gamma ray repeater SGR J1935+2154 entered its intense outburst episode again. Insight-HXMT carried out about one month observation of the source. A total number of 75 bursts were detected during this activity episode by Insight-HXMT, and persistent emission data were also accumulated. We report on the spin period search result and the phase distribution of burst start times and burst photon arrival times of the Insight-HXMT high energy detectors and Fermi Gamma-ray Burst Monitor (GBM). We find that the distribution of burst start times is uniform within its spin phase for both Insight-HXMT and Fermi-GBM observations, whereas the phase distribution of burst photons is related to the type of a burst's energy spectrum. The bursts with the same spectrum have different distribution characteristics in the initial and decay episodes for the activity of magnetar SGR J1935+2154., Comment: 12 pages, 9 figures

PurposeCryptocurrency, an important application of blockchain technology, has gradually circulated, and its use has become widespread. While cryptocurrency is growing rapidly, potential risks are simultaneously emerging. Users thus may abandon their usage behavior of cryptocurrency, hindering the future development of cryptocurrency. While prior studies focus more on the intention to use cryptocurrency in the pre-adoption phase, less studies pay attention to discontinuance usage intention in the post-adoption phase. To fill this knowledge gap, this stfudy aims to explore factors that cause discontinuance usage intention regarding cryptocurrency.Design/methodology/approachBased on the net valence framework theoretically grounded on the theory of reason action, a dilemmatic dual-factor model is proposed to figure out cryptocurrency users' discontinuance usage intention from the perceived risk and perceived benefit. This study identifies four potential risks and three potential benefits that affect perceived risk and benefit. The model with nine hypotheses were developed, and research data were collected by a survey method. A total of 343 valid responses were received, and PLS-SEM with SmartPLS was utilized to test the nine hypotheses, with seven hypotheses supported empirically.FindingsOur findings demonstrate that financial, legal and operational risks are critical to increase users' perceived risk, and perceived usefulness and seamless transactions play important roles in enhancing users' perceived benefit. Moreover, while perceived risk can increase users' discontinuance usage intention to cryptocurrency, perceived benefit can mitigate such intention.Originality/valueThis study contributes nascent knowledge to the literature by examining factors that influence discontinuous usage intention in regard to cryptocurrencies, to firms that have issued or attempted to issue cryptocurrencies and to the potential users of cryptocurrencies by adjusting the mode of operation and investment strategies and reducing user costs, achieving a win-win situation for firms and users.

Incorrect decision-making in financial institutions is very likely to cause financial crises. In recent years, many studies have demonstrated that artificial intelligence techniques can be used as ...

Amino acid-mediated metabolism is one of the key catabolic and anabolic processes involved in diverse cellular functions. However, the role of the semi-essential amino acid arginine in normal and malignant hematopoietic cell development is poorly understood. Here we report that a continuous supply of exogenous arginine is required for the maintenance/function of normal hematopoietic stem cells (HSCs). Surprisingly, knockout of Slc7a3 (CAT3), a major L-arginine transporter, does not affect HSCs in steady-state or under stress. Although Slc7a3 is highly expressed in naïve and activated CD8 T cells, neither T cell development nor activation/proliferation is impacted by Slc7a3 depletion. Furthermore, the Slc7a3 deletion does not attenuate leukemia development driven by Pten loss or the oncogenic Ptpn11E76K mutation. Arginine uptake assays reveal that L-arginine uptake is not disrupted in Slc7a3 knockout cells. These data suggest that extracellular arginine is critically important for HSCs, but CAT3 is dispensable for normal hematopoiesis and leukemogenesis.

An accurate target source position is sometimes useful for the pointing observation with the collimated telescopes of the Hard X-ray Modulation Telescope (Insight-HXMT), which is determined by the reliability of the instrumental response. Insight-HXMT has the unique design that all three main payloads (LE, ME and HE) consist of detector groups with three fields of views (FOVs) whose orientations differ by 60°. As the point-spread functions are different at different positions in the FOV coordinates, the count rate ratios between the detector groups depend on the position of an X-ray source in the FOVs. Based on the multi-FOV design, we develop a localization method for an X-ray source in the pointing observation of Insight-HXMT. The accuracy of the method is investigated with the pointing observations of the Crab with different exposures. We find that the statistical error decreases with the exposure, and the systematic error is dominant for the exposure >128 s. With the exposure of 1024 s, the total error is 0.°015 for the Crab. This method can effectively distinguish the Rapid Burster H 1730–333 and Slow Burster GX 354–0, which are only 0.°5 apart and can both contribute to bursts in the light curve obtained by Insight-HXMT. We also apply the pointing observation localization method to locate the X-ray counterpart of FRB 200428 with high precision. The located position is consistent with SGR J1935+2154 within 1σ uncertainty of 10′, which provides important evidence that fast radio bursts can originate from magnetars.

Key Points Normal hematopoiesis is suppressed by JMML tumor cells as a result of the aberrant activation and exhaustion of stem cells.JMML cells impose inflammatory stress on normal stem cells by over production of IL-1β., Development of normal blood cells is often suppressed in juvenile myelomonocytic leukemia (JMML), a myeloproliferative neoplasm (MPN) of childhood, causing complications and impacting therapeutic outcomes. However, the mechanism underlying this phenomenon remains uncharacterized. To address this question, we induced the most common mutation identified in JMML (Ptpn11E76K) specifically in the myeloid lineage with hematopoietic stem cells (HSCs) spared. These mice uniformly developed a JMML-like MPN. Importantly, HSCs in the same bone marrow (BM) microenvironment were aberrantly activated and differentiated at the expense of self-renewal. As a result, HSCs lost quiescence and became exhausted. A similar result was observed in wild-type (WT) donor HSCs when co-transplanted with Ptpn11E76K/+ BM cells into WT mice. Co-culture testing demonstrated that JMML/MPN cells robustly accelerated differentiation in mouse and human normal hematopoietic stem/progenitor cells. Cytokine profiling revealed that Ptpn11E76K/+ MPN cells produced excessive IL-1β, but not IL-6, T NF-α, IFN-γ, IL-1α, or other inflammatory cytokines. Depletion of the IL-1β receptor effectively restored HSC quiescence, normalized their pool size, and rescued them from exhaustion in Ptpn11E76K/+/IL-1R−/− double mutant mice. These findings suggest IL-1β signaling as a potential therapeutic target for preserving normal hematopoietic development in JMML.

The milestone of GW 170817-GRB 170817A-AT 2017gfo has shown that gravitational wave (GW) is produced during the merger of neutron star-neutron star/black hole and that in electromagnetic (EM) wave a gamma-ray burst (GRB) and a kilonovae (KN) are generated in sequence after the merger. Observationally, however, EM property during a merger is still unclear. Here we report a peculiar precursor in a KN-associated long GRB 211211A. The duration of the precursor is $\sim$ 0.2 s, and the waiting time between the precursor and the main emission (ME) of the burst is $\sim$ 1 s, which is about the same as the time interval between GW 170817 and GRB 170817A. Quasi-Periodic Oscillations (QPO) with frequency $\sim$22 Hz (at $>5\sigma$ significance) are found throughout the precursor, the first detection of periodic signals from any {\it bona fide} GRBs. This indicates most likely that a magnetar participated in the merger, and the precursor might be produced due to a catastrophic flare accompanying with torsional or crustal oscillations of the magnetar. The strong seed magnetic field of $\sim 10^{14-15}$ G at the surface of the magnetar may also account for the prolonged duration of GRB 211211A. However, it is a challenge to reconcile the rather short lifetime of a magnetar \cite{kaspi2017magnetars} with the rather long spiraling time of a binary neutron star system only by gravitational wave radiation before merger., Comment: 37 pages, 14 figures

The mineralization and humification of organic matter triggered by added exogenous carbon is relevant to soil organic matter (SOM) turnover and stability. The dynamic interactions occurring in combined application of typical exogenous carbon materials, here biochar (BC) and artificial humic substance (A-HS), are complex and deserve detailed attention. Herein, a continuous incubation experiment including relevant weather events (freezing, freezing-thawing, warming climates) was conducted for 180 days to observe the development of SOM in the different stages and under separate and mixed applications of A-HS and BC. After 45 d cultivation period and the freezing phase, the relative mineralization rate of SOM was up to 6.4% (120 mL/kg A-HS), 4.9% (2% BC) and 13.3% (for the combination of 120 mL/kg A-HS and 2% BC), suggesting that the presence of A-HS triggers an enhanced mineralization of SOM throughout freezing. However, the remaining SOM turned out to be more strongly humified and more stable, preserving the SOM through the warming season, as shown by ultraviolet fluorescence and high-throughput sequencing. Overall, the dynamic interactions between BC and A-HS are shown to be mainly mediated by biological activity and alterations of microbial community structure and the related metabolic preferred pathways, which vice versa can be influenced by the added carbon sources.

Background The effects of electromagnetic pulse (EMP) radiation on cognitive impairment have attracted much attention, but the mechanism is still unclear. Regulation of brain-derived neurotrophic factor (BDNF) gene expression has been found to promote memory formation and neuronal survival. Isoflurane preconditioning (IP) was reported to have a neuroprotective effect. In this study, we verified the protective effect of IP against brain injury induced by EMP exposure and examined the relation of this effect with BDNF gene regulation. Methods Twenty-four hours before EMP exposure, rats were pretreated with 2% inhaled isoflurane for 30 minutes. At 24 hours after EMP injury, the Morris water maze test was carried out. Meanwhile, the other rats were executed and their brain tissues were used for Nissl staining, qRT-PCR, western blot and chromatin immunoprecipitation. Results The Morris water maze results showed that 2% IP improved the spatial learning and memory ability of the rats. The Nissl staining results showed 2% of IP alleviated neuronal damage. Also, we detected the mRNA and protein expression of BDNF, and 2% IP significantly increased the expression of BDNF. We also found the expression level of histone deacetylase 2 (HDAC2) was increased and that EMP exposure significantly decreased H3 acetylation, while 2% IP reversed these phenomena, individually, BDNF transcription was activated, and neurogenesis after EMP exposure was alleviated. Conclusions Our results suggested that 2% of IP alleviates cognitive impairment induced by EMP exposure in rats. Also, the sustained elevated level of BDNF gene transcription may be an essential mechanism for stimulating neurogenesis because of the increased level of HDAC2-dependent H3 acetylation.

Recently, the system parameters of Cygnus X-1, i.e., the black hole mass M, the orbital inclination i and the source distance D, have been updated. As the input constraints of the continuum-fitting method, it is necessary to refine the spin with these new parameters. The Hard X-ray Modulation Telescope (HXMT, also named Insight) was successfully launched on June 15th, 2017 in China. In this work, we analyzed spectra obtained by the Insight-HXMT during 2017-2018 and re-estimated the spin via the continuum-fitting method. We first re-estimated the spin using old parameters and found the dimensionless spin parameter to be a ⁎ > 0.934 (3σ), which is consistent with previous measurements both from the continuum-fitting and iron-line fitting methods ( Gou et al. 2011 , Gou et al. 2014 ; Fabian et al. 2012 , Walton et al. 2016 , Tomsick et al. 2018 ). Then, when the new parameters were applied, we obtained an increased spin: a ⁎ > 0.967 (3σ), which is also consistent with the recent measurement (Zhao et al. 2020, submitted to ApJ) and also confirms an extreme Kerr black hole lying in this system.

The CsI detectors of the High Energy X-ray Telescope of the Hard X-ray Modulation Telescope (HXMT/CsI) can be used for gamma-ray all sky monitoring and searching for the electromagnetic counterpart of gravitational wave source. The instrumental responses are mainly obtained by Monte Carlo simulation with the Geant4 tool and the mass model of both the satellite and all the payloads, which is updated and tested with the Crab pulse emission in various incident directions. Both the Energy-Channel relationship and the energy resolution are calibrated in two working modes (Normal-Gain mode & Low-Gain Mode) with the different detection energy ranges. The simulative spectral analyses show that HXMT/CsI can constrain the spectral parameters much better in the high energy band than that in the low energy band. The joint spectral analyses are performed to ten bright GRBs observed simultaneously with HXMT/CsI and other instruments (Fermi/GBM, Swift/BAT, Konus-Wind), and the results show that the GRB flux given by HXMT/CsI is systematically higher by 7.0 ± 8.8 % than those given by the other instruments. The HXMT/CsI-Fermi/GBM joint fittings also show that the high energy spectral parameter can be constrained much better as the HXMT/CsI data are used in the joint fittings.

PurposeSince business competition has become more intense throughout the world, most enterprises are seeking to engage in business cooperation with other partners in order to enhance their competitive strengths. However, they do not necessarily develop mature information technologies’ (ITs) capabilities and skills internally but rather outsource them to IT providers. Therefore, the benefits received by firms which adopt the approach of business cooperation with IT providers have become an interesting issue for managers and shareholders.Design/methodology/approachThis study adopted an event study methodology for apprising the short-term business value from the stock market. The authors predicted that investors will react as they receive news coverage about the strategy of business cooperation between outsourcing firms and an IT provider, International Business Machines (IBM) Corporation. The authors then collected all news coverage regarding the firms which had announced business cooperation with IBM and observed different types of abnormal returns.FindingsOn analyzing 53 announcements of cooperation with IBM from 2008 to 2016, the authors found that the announcement of business cooperation had a significantly positive influence on companies' market value.Originality/valueTo the best of the authors’ knowledge, this is the first study to investigate the issue for market reaction to the announcement of business cooperation with IBM.

The Galactic plane scanning survey is one of the main scientific objectives of the Hard X-ray Modulation Telescope (known as Insight-HXMT). During the two-year operation of Insight-HXMT, more than 1000 scanning observations have been performed and the whole Galactic plane ($\rm 0^{\circ}, Comment: 14 pages, 17 figures, accepted for publication in JHEAP

Viscosity-temperature characteristics of high borosilicate glass were investigated in detail by means of rotor viscometer and dilatometer. The neck-down deformation process of glass tube was simulated by Polyflow software, and the simulation was verified by the secondary drawing of glass perform. The results showed that the high temperature viscosity of borosilicate glass is higher compared to that of ordinary optical glass. In the high temperature stage, the fitting curves of VFT, AV, AG and MYEGA models are all in good agreement with the tested curve. However, in the low temperature stage, only viscosity fitted by VFT model is close to the tested value. Based on Navier-Stokes equation, a mathematical model of neck-down deformation of glass tube during secondary drawing is established. It is found that viscosity is the key material intrinsic factor affecting neck-down process of glass tube. The distribution of inner and outer diameters of glass tube along the drawing direction is simulated and analyzed under different feeding and drawing rates. The deviation between the steady-state dimension simulated and that actually drawn is only ±0.06 mm.

Drug addiction is a serious health problem prevalent worldwide. Currently available therapies including pharmacotherapy and psychotherapy are insufficient to meet the clinical needs for treating drug abuse. Recently, immunotherapy has emerged as a promising approach to treat such drug-use disorders. Pharmacokinetic antagonists are used in immunotherapy, functioning by sequestering the drugs in the periphery but without allowing the drug to cross the blood-brain barrier. This can reduce the toxic and rewarding effects of the drugs, while preventing addiction and facilitating reduced relapse rates. Herein, we update recent developments in the immunotherapeutic strategies to treat abuse of drugs like methamphetamine, heroin and cocaine. In addition, we summarize the drug design used so far and its optimization strategies. Further, we document the efficacy of anti-drug vaccines and monoclonal antibodies, with an aim to promote development of new anti-drug immunotherapies.

Purpose As the application of gamification is gaining great attention and has grown increasingly, thousands of these applications can be easily obtained from mobile phone stores, thus causing intensified competition and discontinuance of use accordingly. Besides, though understanding what factors influence the discontinuance of use of information systems (ISs) is critical for theoretical as well as practical reasons, studies pertaining to the saliency of the final phase, termination of an IS, are still limited. As such, the purpose of this paper is to propose a holistic view to fulfill the above-mentioned research gaps based on the expectation-confirmation model with other salient factors such regret, habit and gamification app values. Design/methodology/approach The context of a fitness gamification app is investigated. A total of 210 valid responses were received, and structural equation modeling was applied for data analysis. Findings The findings of this paper are as follows: among all factors influencing discontinuance intention, regret is the strongest, habit is second and gamification is third; among all factors affecting user satisfaction, gamification app value is the strongest, confirmation is second, perceived usefulness (PU) and perceived ease of use are third and regret is the last one; for factors influencing users’ habits, satisfaction is the strongest, following by PU and frequency of prior use; confirmation negatively influences the degree of regret; and confirmation positively influences PU. Originality/value This study highlights the important determinants influencing users’ discontinuance intentions in the context of gamification apps by incorporating two overlooked factors, regret and habit. Besides, this study suggests that app designers can not only increase user’s perceived value through external cooperation with other alternatives, but can be through internal enhancement with diverse services development as well.

Purpose As researchers are writing a draft paper with incomplete structure or text, one of burdensome tasks is to deliberate about which references should be cited for one sentence or paragraph of this draft. In view of the rapid increase in the number of research papers, researchers desire to figure out a better way to do citation recommendations in developing their draft papers. The purpose of this paper is to propose citation recommendation algorithms that enable the acquisition of relevant citations for research papers that are still at the drafting stage. This study attempts to help researchers to select appropriate references among the vast amount of available papers and make draft papers complete in reference citation. Design/methodology/approach This study adopts a model for recommending citations for incomplete drafts. Four algorithms are proposed in this study. The first and second algorithms are unsupervised models, applying term frequency-inverse document frequency and WordNet technologies, respectively. The third and fourth algorithms are based on the second algorithm to integrate different weight adjustment strategies to improve performance. Findings The proposed recommendation method adopts three techniques, including using WordNet to transform vector and setting adjustment weights according to structural factors and the information completeness degree, to generate citation recommendation for incomplete drafts. The experiments show that all these three techniques can significantly improve the recommendation accuracy. Originality/value None of the methods employed in previous studies can recommend articles as references for incomplete drafts. This paper addresses the situation that a draft paper can be incomplete either in structure or text or both. Recommended references, however, can be still generated and inserted into any desired sentence of the draft paper.

Microarray data of hippocampal tissue(HC) of the cognitively intact elderly(60-99 years old) were compared with those of the middle-aged and the young(20-59 years old) by bioinformatics techniques to initially screen out differentially expressed genes(DEGs) and then predict potential effective Chinese medicinals for the treatment of brain aging. The gene expression profile(accession: GSE11882) was downloaded from the Gene Expression Omnibus(GEO) and DEGs were screened based on R package. The key DEGs were identified by STRING, Cytoscape and the plug-in, followed by Gene Ontology(GO) term and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway analysis. Then the key genes and the medical ontology information retrieval platform(Coremine Medical) were mapped against each other to single out the Chinese medicinals for the treatment of brain aging and construct thequot; Chinese medicinal-active constituent-targetquot; network. Among the resultant 268 DEGs(246 down-regulated and 22 up-regulated), the 15 key genes were mainly involved in biological processes such as leukocyte migration, neutrophil activation, cell chemotaxis, microglia activation and response to external stimulus, and pathways such as inflammatory process, immune response, cytokine-cytokine receptor interaction, PI3 K-Akt signaling pathway, Rap1 signaling pathway, chemokine signaling pathway and Toll-like receptor signaling pathway. The potential effective Chinese medicinals were Notoginseng Radix et Rhizoma, Ginseng Radix et Rhizoma, Salviae Miltiorrhizae Radix et Rhizoma and Astragali Radix. The analysis of DEGs and key genes enhances the understanding of the mechanisms of brain aging. This study provides potential gene targets and ideas for the development of Chinese medicine for brain aging.

This study aims to explore the effect of extract of Ginseng Radix et Rhizoma, Notoginseng Radix et Rhizoma, and Chuanxiong Rhizoma(hereinafter referred to as GNS) on the SIRT1-autophagy pathway of endothelial cell senescence induced by hydrogen peroxide(H_2O_2). To be specific, vascular endothelial cells were classified into the blank control group(control), model group(model), model + DMSO group(DMSO), resveratrol group(RESV), and GNS low-dose(GNS-L), medium-dose(GNS-M), and high-dose(GNS-H) groups. They were treated with H_2O_2 for senescence induction except the control. After intervention of cells in each group with corresponding drugs for 24 h, cell growth status was observed under an inverted microscope, and the formation of autophagosome under the transmission electron microscope. In addition, the changes of microtubule-associated protein 1 light chain 3β(LC3 B) were detected by immunofluorescence staining. The autophagy flux was tracked with the autophagy double-labeled adenovirus(mRFP-GFP-LC3) fusion protein. Dansylcadaverine(MDC) staining was employed to determine the autophagic vesicles, and Western blot the expression of sirtuin 1(SIRT1), ubiquitin-binding protein p62, and LC3Ⅱ. After H_2O_2 induction, cells demonstrated slow growth, decreased adhesion ability, raised number of SA-β-gal-stained blue ones, a certain number of autophagosomes with bilayer membrane and secondary lysosomes in the cytoplasm, and slight rise of autophagy flux level. Compared with the model group, GNS groups showed improved morphology, moderate adhesion ability, complete and smooth membrane, decreased SA-β-gal-stained blue cells, many autophagosomes, autophagic vesicles, and secondary lysosomes in the cytoplasm, increased autophagolysosomes, autophagy flux level, and fluorescence intensity of LC3 B and MDC, up-regulated expression of SIRT1 and LC3Ⅱ, and down-regulated expression of p62, suggesting the improvement of autophagy level. GNS can delay the senescence of vascular endothelial cells. After the intervention, the autophagy flux and related proteins SIRT1, LC3Ⅱand p62 changed significantly, and the autophagy level increased significantly. However, EX527 weakened the effect of Chinese medicine in delaying vascular senescence. GNS may delay the senescence of vascular endothelial cells through the SIRT1 autophagy pathway.

This study explored the molecular mechanism behind the protective effects from low-dose lipopolysaccharide (LPS) on an in-vitro model of spinal cord injury (SCI). For this, PC12 cells were treated with different concentrations of LPS and the cell counting kit-8 assay was used to measure the toxicity of LPS to the cells. Next, we used immunofluorescence to measure nuclear translocation of Nrf2 in PC12 cells. PC12 cells were then treated with IGF-1 (PI3K agonist) and LY294002 (PI3K inhibitor). An in-vitro model of SCI was then established via oxygen–glucose deprivation/reoxygenation. Rates of apoptosis were measured using flow cytometry and the TUNEL assay. Low-dose LPS increased the expression levels of Nrf2, p-PI3K/PI3K, and p-AKT/AKT, and facilitated nuclear translocation of Nrf2. The activation of PI3K–AKT signaling by IGF-1 significantly increased the expression of Nrf2, whereas inhibition of PI3K–AKT signaling significantly decreased the expression of Nrf2. Low-dose LPS reduced the apoptotic ratio of PC12 cells, decreased the expression levels of caspase 3 and caspase 9, and increased the expression levels of HO-1, NQO1, and γ-GCS. Low-dose LPS also reduced the rate of apoptosis and oxidative stress by activating the PI3K–AKT–Nrf2 signaling pathway. Collectively, the results indicate that PI3K–AKT–Nrf2 signaling participates in the protective effects from low-dose LPS in an in-vitro PC12 cell model of SCI.

Environmental stresses, including hypoxia or detachment for anchorage independence, or attenuation of mitochondrial respiration through inhibition of electron transport chain induce reductive carboxylation in cells with an enhanced fraction of citrate arising through reductive metabolism of glutamine. This metabolic process contributes to redox homeostasis and sustains biosynthesis of lipids. Reductive carboxylation is often dependent on cytosolic isocitrate dehydrogenase 1 (IDH1). However, whether diverse cellular signals induce reductive carboxylation differentially or through a common signaling converging node remains unclear. We found that induction of reductive carboxylation commonly requires enhanced tyrosine phosphorylation and activation of IDH1, which, surprisingly, is achieved by attenuation of a cytosolic protein tyrosine phosphatase, Src homology region 2 domain-containing phosphatase-2 (SHP-2). Mechanistically, diverse signals induce reductive carboxylation by converging at upregulation of NADPH oxidase 2, leading to elevated cytosolic reactive oxygen species that consequently inhibit SHP-2. Together, our work elucidates the signaling basis underlying reductive carboxylation in cancer cells.

The Internet of Things connects devices or sensors to the Internet for data collection and exchange. These pieces of data provide rich information about production and inventory as well as sales and marketing efforts.

Immature phenotypes of cardiomyocytes derived from human induced pluripotent stem cells (hiPSC-CMs) limit the utility of these cells in clinical application and basic research. During cardiac development, postnatal cardiomyocytes experience high oxygen tension along with a concomitant downregulation of hypoxia-inducible factor 1α (HIF-1α), leading to increased fatty acid oxidation (FAO). We hypothesized that targeting HIF-1α alone or in combination with other metabolic regulators could promote the metabolic maturation of hiPSC-CMs. We examined the effect of HIF-1α inhibition on the maturation of hiPSC-CMs and investigated a multipronged approach to promote hiPSC-CM maturation by combining HIF-1α inhibition with molecules that target key pathways involved in the energy metabolism. Cardiac spheres of highly-enriched hiPSC-CMs were treated with a HIF-1α inhibitor alone or in combination with an agonist of peroxisome proliferator activated receptor α (PPARα) and three postnatal factors (triiodothyronine hormone T3, insulin-like growth factor-1 and dexamethasone). HIF-1α inhibition significantly increased FAO and basal and maximal respiration of hiPSC-CMs. Combining HIF-1α inhibition with PPARα activation and the postnatal factors further increased FAO and improved mitochondrial maturation in hiPSC-CMs. Compared with mock-treated cultures, the cultures treated with the five factors had increased mitochondrial content and contained more cells with mitochondrial distribution throughout the cells, which are features of more mature cardiomyocytes. Consistent with these observations, a number of transcriptional regulators of mitochondrial metabolic processes were upregulated in hiPSC-CMs treated with the five factors. Furthermore, these cells had significantly increased Ca(2+) transient kinetics and contraction and relaxation velocities, which are functional features for more mature cardiomyocytes. Therefore, targeting HIF-1α in combination with other metabolic regulators significantly improves the metabolic maturation of hiPSC-CMs.

Amino acid (AA) metabolism is involved in diverse cellular functions, including cell survival and growth, however it remains unclear how it regulates normal hematopoiesis versus leukemogenesis. Here, we report that knockout of Slc1a5 (ASCT2), a transporter of neutral AAs, especially glutamine, results in mild to moderate defects in bone marrow and mature blood cell development under steady state conditions. In contrast, constitutive or induced deletion of Slc1a5 decreases leukemia initiation and maintenance driven by the oncogene MLL-AF9 or Pten deficiency. Survival of leukemic mice is prolonged following Slc1a5 deletion, and pharmacological inhibition of ASCT2 also decreases leukemia development and progression in xenograft models of human acute myeloid leukemia. Mechanistically, loss of ASCT2 generates a global effect on cellular metabolism, disrupts leucine influx and mTOR signaling, and induces apoptosis in leukemic cells. Given the substantial difference in reliance on ASCT2-mediated AA metabolism between normal and malignant blood cells, this in vivo study suggests ASCT2 as a promising therapeutic target for the treatment of leukemia.

To balance the electrochemical performance gap between the Li+ insertion/deintercalation anode and the anion adsorption/desorption cathode, in this paper, for the first time, we investigated MnNb2O6 as a new rate capability type anode material for lithium-ion capacitors (LICs). Novel calendula-like MnNb2O6 particles anchored on reduced graphene oxide (rGO) were prepared via a simple two-step hydrothermal route. The special three-dimensional structure and cross-linked conductive network constructed by graphene could shorten the lithium-ion diffusion path, efficiently facilitate electron transmission and adapt to volume strain without shedding during the long-term charge/discharge process. This resulted in excellent charge storage capacity and reasonably superior cycling stability. MnNb2O6@rGO//AC LICs assembled with MnNb2O6@rGO as the cathode and activated carbon (AC) as the anode exhibited excellent performance with maximum energy density of 118 W h kg−1 and power density of 8000 W kg−1 based on the total mass loading of the active material weight. The initial capacity retention was up to 88% after 10 000 charge/discharge cycles, which was higher than that of bimetallic oxide materials reported so far. Therefore, this study might provide a novel rate capability anode material for LICs with high performance.

Accurately estimating of diffuse X-ray background (DXB) is essential for the investigation of sources in the Galactic plane observed with Insight-HXMT/LE, which is a collimated telescope in the soft X-ray energy band with a relatively large field of view. In the high-Galactic-latitude region, DXB is dominated by the cosmic X-ray background, which is almost uniform, but DXB in the Galactic plane region is more complex due to the Galactic H i absorption and the contribution of the Galactic ridge X-ray emission. This study, as a part of background estimation of LE, focuses on estimating the contribution of DXB in the Galactic plane to Insight-HXMT/LE observations. We calculate DXB confined in a region of 0° < l < 360° and ∣b∣ < 10°, where l and b denote Galactic longitude and latitude, respectively, with the first 3 yr of Galactic-plane-scanning survey data of Insight-HXMT/LE. The Galactic plane is divided into 360 × 20 small pixels (1° × 1° per pixel), and a DXB spectrum is obtained for each pixel. An indirect method is developed for the pixels of the bright source regions, which brings a systematic error of ∼10%. The systematic error brought by the satellite attitude is ∼7% on average for all the pixels in the Galactic plane. The LE DXB spectrum obtained in this study is consistent with that reported by RXTE’s Proportional Counter Array.

Since April 28, 2020, Insight-HXMT has implemented a dedicated observation on the magnetar SGR J1935+2154. Thanks to the wide energy band (1-250 keV) and high sensitivity of Insight-HXMT, we obtained 75 bursts from SGR J1935+2154 during a month-long activity episode after the emission of FRB 200428. Here, we report the detailed time-integrated spectral analysis of these bursts and the statistical distribution of the spectral parameters. We find that for 15%(11/75) of SGR J1935+2154 bursts, the CPL model is preferred, and most of them occurred in the latter part of this active epoch. In the cumulative fluence distribution, we find that the fluence of bursts in our sample is about an order of magnitude weaker than that of Fermi/GBM, but follows the same power law distribution. Finally, we find a burst with similar peak energy to the time-integrated spectrum of the X-ray burst associated with FRB 200428 (FRB 200428-Associated Burst), but the low energy index is harder., 35 pages, 20 figures, accepted for publication in ApJS

GRB 190 530A was jointly observed by the High Energy X-ray Telescope of the Hard X-ray Modulation Telescope (Insight-HXMT/HE) and the Ground-Based Wide-Angle Camera network (GWAC-N) with the extremely large field of view. After triggered by Insight-HXMT/HE and Fermi/GBM, we observed the optical emission of GRB 190 530A, using the 30 cm telescope of GWAC (GWAC-F30) to search and locate its position. Subsequent observation of the late afterglow of GRB 190 530A was made with the 2.16 m telescope at Xinglong Observatory. In this paper, we make a detailed exploration of the origin of GRB 190 530A. In the prompt emission, a “double-tracking” pattern is presented both for the low-energy spectral index α and the peak energy E p in the Band function with Insight-HXMT/HE and Fermi/GBM data; the results of GRB 190 530A are consistent with the Amati and Yonetoku correlations; the spectral lag (τ) versus energy (E) can be estimated with τ = − 3.0 ± 0.06 + ( 0.17 ± 0.03 ) log E . The synchrotron radiation can account for the origin of GRB 190 530A prompt emission behaviors. The α and E p of the precursor are essentially the same as that of the main prompt emission, implying that they have the same origin. For the afterglow, it can be described with the external forward shock model in ISM circumburst medium. In summary, from precursor, prompt emission to afterglow of GRB 190 530A all originated from synchrotron radiation.