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Given the unwieldy glut of information in online health question-answer (Q&A) service, it is essential to understand what constitutes helpful answers in the medical domain. Despite the fact that studies have examined the impacts of answer content factors on answer helpfulness, there are two gaps that need further analysis. First, the empirical results of the existing relevant studies on the effect of answer emotion are inconsistent. Second, prior studies only have examined the independent impacts of answer content factors and question content cues on answer helpfulness. To fill this gap, a research model reflecting the impacts of emotional content and question-answer congruence on answer helpfulness was developed and empirically examined. Our empirical analyses confirm that emotional content and answer helpfulness are related to one another in the form of an inverted U-shape and indicate that two types of question-answer congruence (emotional intensity congruence and linguistic style matching) positively affect answer helpfulness. Theoretical and practical implications are discussed., Author(s): Dongmei Han, Shanghai University of Finance and Economics, Shanghai, China, Lifeng He, Qingdao University, China, Wenfei Zhao, Shanghai University of Finance and Economics, China, Xiaohang Zhou, Qingdao City University, [...]

Given the unwieldy glut of information in online health question-answer (Q&A) service, it is essential to understand what constitutes helpful answers in the medical domain. Despite the fact that studies have examined the impacts of answer content factors on answer helpfulness, there are two gaps that need further analysis. First, the empirical results of the existing relevant studies on the effect of answer emotion are inconsistent. Second, prior studies only have examined the independent impacts of answer content factors and question content cues on answer helpfulness. To fill this gap, a research model reflecting the impacts of emotional content and question-answer congruence on answer helpfulness was developed and empirically examined. Our empirical analyses confirm that emotional content and answer helpfulness are related to one another in the form of an inverted U-shape and indicate that two types of question-answer congruence (emotional intensity congruence and linguistic style matching) positively affect answer helpfulness. Theoretical and practical implications are discussed.

Studying the impact of terrain undulation on low-frequency (LF) sky-wave propagation delay is of great significance for exploring the potential applications in low-ionospheric detection, remote navigation, and timing service. This letter combines gradient ionospheric parameters and uses the finite-difference time-domain method to calculate the reflected signal of LF radio waves from the ionosphere. Using the sky- and ground-wave separation technologies in time domain, the variation law of LF sky-wave propagation delay with terrain changes is given in both daytime and nighttime models. At the same time, this letter also analyzes the influence of different ionospheres (in the presence or absence of natural magnetic field) on LF one-hop sky-wave propagation delay, providing some reference significance for studying the propagation characteristics of LF sky waves.

The abundance of user ideas in the open innovation community poses a challenge of information overload for enterprises, making it difficult to effectively adopt ideas for product innovation. Existing studies primarily focus on evaluating the usefulness of user ideas, while overlooking the actual adoption outcomes of these ideas. Based on the information adoption model, this paper proposes a user idea adoption model, which integrates the two stages of idea collection and idea application. The authors creatively discuss the factors influencing the process from “perceived usefulness” to “adoption” of a user idea, and explore the complete mechanism of user idea adoption for product innovation. The results show that the information quality and source credibility of user ideas affect the perceived usefulness. The degree of user demand, innovation complexity, and competition intensity have moderating effects on the relationship between the perceived usefulness of user ideas and the results of user ideas adoption.

Common medical image segmentation tasks require large training datasets with pixel-level annotations which are very expensive and time-consuming to prepare. To overcome such limitation and achieve the desired segmentation accuracy, a novel Weakly-Interactive-Mixed Learning (WIML) framework is proposed by efficiently using weak labels. On one hand, utilize weak labels to reduce annotation time for high-quality strong labels by designing a Weakly-Interactive Annotation (WIA) part of the WIML which prudently introduces interactive learning into the weakly-supervised segmentation strategy. On the other hand, utilize weak labels and very few strong labels to achieve desired segmentation accuracy by designing a Mixed-Supervised Learning (MSL) part of the WIML which can boost the segmentation accuracy by providing strong prior knowledge during training. Besides, a multi-task Full-Parameter-Sharing Network (FPSNet) is proposed to better implement this framework. Specifically, to further reduce annotation time, attention modules (scSE) are integrated into FPSNet to improve the class activation map (CAM) performance for the first time. To further improve segmentation accuracy, a Full-Parameter-Sharing (FPS) strategy is designed in FPSNet to alleviate the overfitting of the segmentation task supervised by very few strong labels. The proposed method is validated on the BraTS 2019 and LiTS 2017 datasets, and experiments demonstrate that the proposed method WIML-FPSNet outperforms several state-of-the-art segmentation methods with minimal annotation efforts.

Accurate detection of obstructive sleep apnea (OSA) with a single-lead electrocardiogram (ECG) signal is highly desirable for the timely treating of OSA patients. However, due to the variance of apneas in appearance and size in ECG signals, it is still a very challenging task to obtain an accurate OSA apnea detection. To address this problem, this article presents a time–frequency information fusion-based CNN-Transformer model (TFFormer) for OSA detection with single-lead ECG, in which a module consisting of a deep residual shrinkage module, a multiscale convolutional attention (MSCA) module, and a multilayer convolution module is developed for time–frequency feature extraction. The purpose of this operation is to extract rich features from a short length of ECG signal sequences with a low computation cost. For time–frequency information fusion, to reduce its computation cost, a gated self-attention-based adaptive pruning time–frequency information fusion attention module is developed to prune the redundant tokens. With the attention-based adaptive pruning time–frequency information fusion module, the TFFormer is constructed for data-parallel processing and long-distance modeling. Compared with the best model in the comparative method, the accuracy of the proposed method was improved by 0.18% in the segmented case, and the mean absolute error was reduced by 0.25 per-recorded case, which demonstrates that the TFFormer model has better OSA detection performance and could provide a convenient and accurate solution for clinical OSA detection.

ABSTRACTThe aim of our study was to explore the relationship between the methylation status of the alpha-1A adrenergic receptor(ADRA1A) gene and hepatocellular carcinoma (HCC). We combined our in-house data-set with the Cancer Genome Atlas (TCGA) data-set to screen and identify the methylation status and expression of adrenergic receptor (AR) genes in HCC. Immunohistochemistry and western blot were performed to assess the expression of ADRA1A in HCC cell lines and tissues. We further evaluated the methylation levels of the ADRA1Apromoter region in 160 HCC patients using the Sequenom MassARRAY® platform and investigated the association between methylation of ADRA1Aand clinical characteristics. The expression levels of ADRA1A mRNA and protein were significantly decreased in HCC tissues. Compared with that in paired normal tissues, the mean methylation level of the ADRA1Apromoter region was significantly increased in tumour tissues from 160 HCC patients (25.2% vs. 17.0%, P < 0.0001). We found that a DNA methyltransferase inhibitor (decitabine) could increase the expression of ADRA1AmRNA in HCC cell lines. Moreover, hypermethylation of the ADRA1Agene in HCC samples was associated with clinical characteristics, including alcohol intake (P = 0.0097) and alpha-fetoprotein (P = 0.0411). Receiver operator characteristic (ROC) curve analysis demonstrated that the mean methylation levels of ADRA1Acould discriminate between HCC tissues and adjacent non-cancerous tissues (AUC = 0.700, P < 0.0001). mRNA sequencing indicated that the main enriched pathways were pathways in cancer, cytokine-cytokine receptor interaction and metabolic pathways (P < 0.01). ADRA1Agene hypermethylation might contribute to HCC initiation and is a promising biomarker for the diagnosis of HCC.

Combined the big data from Chinese researches and our clinical experiences, we drew a concise “distributed map” of intractable epistaxis showing the concealed bleeding regions and offending vessels clearly (Figure 1). The bleeding site was located accurately according to the “distributed map,” and bleeding was stopped via bipolar radiofrequency ablation under nasal endoscope without nasal packing, followed by five classic cases (Figure 2). It is our recommended precise mode of diagnosis and treatment of refractory epistaxis.

The modification of commercial ultra-stable Y zeolites using citric acid and phosphoric acid was investigated systematically via a L18(38) orthogonal experiment. The pore structure, acid property and crystal structural of modified USY zeolites were characterized by a variety of means such as N2adsorption–desorption, Fourier transform infrared spectroscopy, NH3-temperature programmed desorption and X-ray diffraction. The optimal modification condition is found to be that the volume ratio of citric acid (0.3 mol/L) and phosphoric acid (0.3 mol/L) is 1.0, and the operation is performed at 100 °C for 6 h. The as-synthesized sample presents an increased secondary pore volume up to 0.207 cm3/g which accounts for 42.9 % of the total pore volume, and appropriate acidity distribution as well as good crystallinity. In addition, the USY obtained by 1.0 L scale-up modification possesses a secondary pore volume of 0.210 cm3/g which accounts for 42.4 % of the total pore volume, showing no obvious scale-up effects. Furthermore, the hydrothermal stability of the modified samples meets the requirements of commercial catalysts for hydrocracking. Performance evaluation was carried out on a 200 mL fixed-bed single stage hydrogenation unit using Daqing VGO as feedstock. The 140–370 °C middle distillate yield is 66.09 %, and middle distillate selectivity can reach up to 80.45 %. Compared with commercial catalyst, the yield and selectivity are increased by 5.67 and 4.07 %, respectively.

The modification of commercial ultra-stable Y (USY) zeolite using citric acid (CA) and ammonium fluosilicate (AFS) was investigated. A series of factors including the concentration of CA and AFS, the volume ratio of CA and AFS, adding rate of AFS, reaction time and temperature were studied to get the optimum operation condition. The pore structure, acid property and crystal structural of modified USY zeolite were characterized by a variety of means such as N2adsorption, Fourier transform infrared spectroscopy, NH3-temperature programmed desorption and X-ray diffraction. The as-synthesized sample presents an increased secondary pore volume up to 0.20 cm3/g which accounts for 46.5 % of the total pore volume, and appropriate acidity distribution as well as good crystallinity. In addition, the modified USY zeolite possesses a superhigh Si/Al ratio of 25.7 which is more than twice higher than that of commercial USY zeolite. Furthermore, the hydrothermal stability of the modified samples meet the requirements of commercial catalysts for hydrocracking. Performance evaluation was carried out on a 200 mL fixed-bed single stage hydrogenation unit using Daqing VGO as feedstock. The 140–370 °C middle distillate yield is 67.78 %, and middle distillate selectivity can reach up to 80.76 %. Compared with commercial catalyst, the yield and selectivity are increased by 7.36 and 4.38 %, respectively.

This paper introduces some improvements on the intelligent backtracking strategy for forward chaining theorem proving. How to decide a minimal useful consequent atom set for a refutation derived at a node in a proof tree, is discussed. In most cases, an unnecessary non-Horn clause used for forward chaining will be split only once. The increase of the search space by invoking unnecessary forward chaining clauses will be nearly linear, not exponential anymore. In this paper, the principle of the proposed method and its correctness are introduced. Moreover, some examples are provided to show that the proposed approach is powerful for forward chaining theorem proving.

This paper presents an improvement ofA-SATCHMORE (SATCHMORE with Availability).A-SATCHMORE incorporates relevancy testing and availability checking into SATCHMO to prune away irrelevant forward chaining. However, considering every consequent atom of those non-Horn clauses being derivable,A-SATCHMORE may suffer from a potential explosion of the search space when some of such consequent atoms are actually underivable. This paper introduces a solution for this problem and shows its correctness.

We introduce a method for reducing the redundant search space for SATCHMO's model generation approach by means of intelligent backtracking. During the reasoning, we mark an asserted consequent atom as “useful” whenever it has been used as an antecedent atom for forward chaining. We show that a splitting of the consequence of a non-Horn clause is unnecessary if one of its consequent atoms is found not to be “useful” at the time it is retracted from the database on backtracking, and therefore the remaining splitting over the clause's consequence can be immediately abandoned. In this way, much of the redundant search space can be eliminated. Our method is simple in principle, easy to implement in Prolog, independent of other refinements, and effective for model generation theorem proving.

Abstract: Purpose: Eleutherobin, a natural product, is an antimitotic agent that promotes the polymerization of stable microtubules. Although its mechanism of action is similar to that of Taxol, its structure is distinct. A structure-activity profile of synthetic eleutherobin derivatives that have modifications at C3, C8 and C15 was undertaken to define the structural requirements for microtubule stabilization and cross-resistance in Taxol-resistant cell lines. Methods: The biological activity of five eleutherobin analogs was assessed using three techniques; (1) cytotoxicity and drug-resistance in three paired Taxol-sensitive and -resistant cell lines; (2) polymerization of microtubule protein in vitro in the absence of GTP and (3) induction of microtubule bundle formation in NIH3T3 cells. Results: Eleutherobin had an IC50 value comparable to that of Taxol, whereas neo-eleutherobin, which has a carbohydrate domain that is enantiomeric with that of the parent compound, was less cytotoxic and had 69% of the maximum microtubule polymerization ability of eleutherobin. Both of these compounds exhibited cross-resistance in MDR1-expressing cell lines. Removal or replacement of the C15 sugar moiety resulted in reduced microtubule polymerization and cytotoxicity compared to eleutherobin and loss of cross-resistance in the cell lines SKVLB and J7-T3-1.6, both of which express high levels of P-glycoprotein. By contrast, removal of the urocanic acid group at C8 resulted in virtually complete abrogation of biological activity. The compound lost its ability to polymerize microtubules, and its cytotoxicity was reduced by a minimum of 2000-fold in lung carcinoma A549 cells. Conclusions: Removal or modification of the sugar moiety alters the cytotoxic potency of eleutherobin and its pattern of cross-resistance in Taxol-resistant cells, although such compounds retain a small percentage of the microtubule-stabilizing activity of eleutherobin. The N(1)-methylurocanic acid moiety of eleutherobin, or perhaps some other substituent at the C8 position, is essential for Taxol-like activity. These findings will be important for the future design and the synthesis of new and more potent eleutherobin derivatives.

The title compounds have been synthesized in a convergent way by recourse to a Weiler type dianion construction.

The title compound retains some of the affinity for microtubule assemblies as does 12,13-desoxyepothilone B.

Metablastin (also called p19, stathmin, prosolin, p18, Lap18, and oncoprotein 18) is a highly conserved, cytosolic 149-amino acid polypeptide that is expressed in immature vertebrate cells and undergoes extracellular factor- and cell cycle-regulated serine phosphorylation. The protein was shown recently to destabilize microtubules in vitro(Belmont, L., and Mitchison, T. J. (1996) Cell84, 623–631). Here we demonstrate that microinjection of recombinant metablastin induces a loss of microtubules in COS-7 cells. This effect is enhanced by serine-to-alanine mutations at several phosphorylation sites and virtually abolished by aspartate substitution at a single site, Ser-63. We also show that stoichiometric amounts of metablastin prevent assembly and promote disassembly of microtubules in vitro. Interestingly, the phosphorylation site mutations of metablastin that have dramatic differential effects in intact cells do not alter the ability of metablastin to block tubulin assembly in vitro. The data suggest that phosphorylation of metablastin controls its microtubule-destabilizing activity in vivobut that this regulation may require additional cellular factors. This control mechanism is poised to play a critical role in the dynamic reorganization of the cellular microtubule network that occurs during morphogenesis and mitosis.

We present an improvement of SATCHMORE, calledA-SATCHMORE, by incorporating availability checking into relevancy. Because some atoms unavailable to the further computation are also marked relevant, SATCHMORE suffers from a potential explosion of the search space. Addressing this weakness of SATCHMORE, we show that an atom does not need to be marked relevant unless it is available to the further computation and no non-Horn clause needs to be selected unless all its consequent atoms are marked availably relevant, i.e., unless it is totally availably relevant. In this way,A-SATCHMORE is able to further restrict the ues of non-Horn clauses (therefore to reduce the search space) and makes the proof more goal-oriented. Our theorem prover,A-SATCHMORE, can be simply implemented in PROLOG based on SATCHMORE. We discuss how to incorporate availability cheeking into relevancy, describe our improvement and present the implementation. We also prove that our theorem prover is sound and complete, and provide examples to show the power of our availability approach.

Geringfügig überlegenist Epothilon B 1(R = Me) gegenüber Paclitaxel (Taxol) im Hinblick auf die Antitumoraktivität. Dies geht aus In‐vivo‐Untersuchungen mit Tumormodellen in der Maus hervor. Sehr empfindlich gegenüber Strukturänderungen ist bei den Epothilonen der „Acylsektor”︁ C1C8. Die anderen beiden Sektoren (siehe rechts) können in Grenzen variiert werden, allerdings wurde dabei bisher noch keine deutlich antitumoraktivere Verbindung identifiziert.

Ahead!Epothilone B (1, R?Me) displayed better antitumor activity than paclitaxel (Taxol), as shown by in vivo studies with resistant mouse tumor models. The “acyl sector” C1?C8 in the epothilones is very sensitive to modification. The other two sectors (see structure on the right) can be varied to a certain extent; however, none of the analogues examined thus far have surpassed the parent compound.

The highest biological activitiesdisplayed by epothilone-related compounds have been found for epothilone B (1) and a derivative that was prepared en route to the natural product. Key steps in the total synthesis were a Suzuki coupling providing a trisubstituted double bond in the macrocycle and its subsequent stereoselective epoxidation with dimethyldioxirane.

Biologisch ähnlich wirksamwie Epothilon B 1ist ein Derivat, das bei der Synthese von 1hergestellt wurde. Schlüsselschritte in der ersten Totalsynthese des Naturstoffs 1waren eine Suzuki‐Kupplung, die eine trisubstituierte Doppelbindung im Makrocyclus lieferte, und eine anschließende stereoselektive Epoxidierung mit Dimethyldioxiran.

In the optical measurement of burst multi-targets such as the rocket, missile, bullet and so on, in order to solve the poor real-time reliability problem of the multi-targets ballistic recognition caused by the invalid ballistic recognition algorithm variable and less movement feature quantity, a multi-targets ballistic recognition method based on movement multiple feature correlation has been proposed, and the mathematical model algorithm and multi-targets real-time ballistic recognition strategy has been established at the same time. It has been proved that the method can improve the adaptability, real-time performance and reliability of multi-targets real-time ballistic recognition, to provide technical support to real-time multi-targets optical measurement and processing.

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Looks at the economic potentials of Fuzhou, provincial capital of Fujian, China. Efforts of the city to attract foreign investments; Increase in export volume; Favorable natural conditions; Significance of infrastructure construction and reforms; Local government's effort to cut red tape.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.