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Using data of Chinese A-share non-financial listed companies spanning years 2003–2018, we examine whether a firm’s business strategy that deviates from industry conventions influences corporate gov...

Many studies have been carried out the car experience from functional view. Different from these studies, our study aims to find more detailed reason for customers to choose the car of interest from the perspective of the whole car experience. Such experience is that feeling of using a car product to form a comprehensive feeling of the automobile product. The effective study of car experience is necessary for thinking about car product innovation at a strategic level. However, reflection on this issue has not received sufficient involvement in previous studies. Therefore, we use a qualitative research based on phenomenological methods to interview a candidate. By analyzing the interview scripts, 19 kinds of experience elements are extracted in the car experience. We also discovered four main mechanisms of vehicle experience behavior, which provides useful strategic theoretical guidance for the innovative practice of automotive product experience for Generation Z customers. In addition, our study shows that descriptive phenomenon analysis and explanatory phenomenon analysis are effective method tools for carrying out scientific research on the vehicle experience.

We propose a fiber-solid hybrid amplifier system which consists of a semiconductor saturable absorber mirror (SESAM) mode-locked fiber seed with pulse width of 10.6 ps and repetition rate of 17.6 MHz, a two-stage fiber pre-amplifier and a Nd: YAG regenerative amplifier. This structure not only endures high peak power, but also reduces the influence of fiber nonlinear effects. In the regenerative amplifier, a Pockels cell made up of BBO crystal is used as the electro-optical Q switch. It can effectively amplify the fiber seed source while keeping the beam quality constant. Besides, the pulse frequency, round trip time and thermal lens effect of the regenerative amplifier are considered and the stability of the high repetition rate regenerative cavity is further improved. The system achieves average powers of 1.5, 2.5, 3.4 W at the repetition rates of 1, 3, 5 kHz, corresponding to single pulse energies of 1.5, 0.83, 0.68 mJ respectively. And the beam quality factor M2 reaches 1.5 at the output power of 3.4 W. This system will make significant contributions to many fields such as material micro-processing, laser ranging, and laser detection. To make it more systematizing and engineering, we design an engineering prototype of the fiber-solid hybrid amplifier system.

For students majored in computer science, the ability to have computational thinking is an essential skill. Facilitating computational thinking cannot only help students understand the professional knowledge and principles of computer, but also bring new ideas to addressing complex problems, therefore, many colleges and universities have carried out computer professional curriculum reform based on computational thinking. Due to the high degree of abstraction of computational thinking, traditional teaching methods will cause students to understand computational thinking only at the conceptual level, and cannot realize the flexible use of computational thinking concepts. This study takes the software engineering course as an example to explain how to integrate the concepts of computational thinking into the original courses. The goal is to enable students to understand software engineering contents problems from the perspective of problem-solving.

Objective. Since early diagnosis is very important for treating gastric cancer (GC), we aimed to detect serum small proline-rich protein2A (SPRR2A) to verify its diagnostic value for GC patients. Methods. Serum samples were collected from 200 patients with GC, 100 patients with gastritis, 40 patients with rectal cancer (RC), 50 patients with colon cancer (CC), and 100 healthy controls. An enzyme-linked immunosorbent assay (ELISA) detection kit was applied to measure serum SPRR2A concentration. The correlations between serum SPRR2A and carcinoembryonic antigen (CEA), clinical pathological parameters of GC, and receiver operating characteristic (ROC) curve were also analyzed. Results. The median serum SPRR2A concentration in GC patients was significantly higher than those in healthy controls and gastritis or colorectal cancer patients (P<0.001). Serum SPRR2A concentration at a cut-off value of 80.7 pg/ml yielded an AUC of 0.851, with 75.7% sensitivity and 74.5% specificity for discriminating GC patients from healthy people. The AUC for the serum SPRR2A concentration combined with the CEA concentration was 0.876, with 79.7% sensitivity and 78.7% specificity. Similarly, serum SPRR2A discriminated GC patients from gastritis patients with an AUC of 0.820, with 90.5% sensitivity and 61.7% specificity. The AUC for the serum SPRR2A concentration combined with the CEA concentration was 0.848, with 87.8% sensitivity and 68.1% specificity. The serum SPRR2A levels in GC patients were associated with lymph node metastasis and the tumor-node-metastasis (TNM) stage (P<0.05). There was an obvious difference in serum SPRR2A expression between GC patients before and after surgery (P<0.0001). Conclusion. These results suggest that serum SPRR2A can be used as an effective marker for GC.

Social media technology creates an opportunity to shift the formation of impersonal relationships from offline to online. The theory of IT affordances provides a basis for theorizing how the use of online social commerce (OSC) technology facilitates the formation of social ties in an OSC context. In this paper, integrating theories of IT affordances and social ties, we develop a model to explore how the six sub-dimensions of OSC IT affordances (i.e., visibility, metavoicing, triggered attending, guidance shopping, social connecting, and trading) aid buyers and sellers in building strong and weak OSC ties. A survey of 511 buyers from WeChat shows that five of the six IT affordances enhance the quality of interactivity, and thereby facilitate social ties (both strong and weak), which in turn contribute to buyers’ repurchase intentions. Additionally, the findings confirm the positive moderating effect of perceived effectiveness of e-commerce institutional mechanisms (PEEIM) on the strong tie formation process. This paper advances the affordances and social tie literature by examining the antecedents and outcomes of OSC social ties in more detail. Our findings not only benefit the researchers in interpreting how technology helps form different types of relationships in OSC, but also assists practitioners in developing better OSC management strategy.

Background: Increasing studies suggest that long noncoding RNAs (lncRNAs) are involved in carcinogenesis of human cancers and might be used as diagnostic biomarkers for cancers. Methods: A total of 301 participants were recruited in the first part of the study, including a hepatocellular carcinoma (HCC) group (n = 60), liver cirrhosis (LC) group (n = 85), chronic hepatitis B (CHB) group (n = 96), and healthy subjects (n = 60). In the second part, we collected 55 HCC patients, 60 CHB patients, and 60 healthy subjects as an independent cohort to validate the ability of the experiential lncRNAs for identifying HCC from CHB. A commercial kit was used to isolate serum exosomes and total RNA. The relative levels of lnRNAs and GAPDH mRNA were measured with TaqMan PCR. Results: The results showed that the levels of ENSG00000258332.1 and LINC00635 in the HCC group were significantly higher than those in the other groups (all P < 0.05). A high ENSG00000258332.1 level in HCC was associated with portal vein tumor emboli, lymph node metastasis, TNM stage, and overall survival (OS; all P < 0.05), and a high LINC00635 level was related to lymph node metastasis, TNM stage, and OS (all P < 0.05). ENSG00000258332.1 discriminated HCC from CHB, gaining an area under the ROC curve (AUC) of 0.719 (cutoff value of 1.345); LINC00635 gained an AUC of 0.750 (cutoff value of 1.690). Furthermore, the AUC for the combination of the 2 lncRNAs and serum AFP (cutoff value of 20 μg/L) was 0.894. The abilities of the 2 lncRNAs for identifying HCC from CHB were validated by an independent cohort. Conclusions: The results suggested that the combination of serum exosomal ENSG00000258332.1, LINC00635, and AFP may be a valuable assay in diagnosis and prognosis of HCC. Impact: Our data will shed light on exosomal lncRNAs as biomarkers for HCC. Cancer Epidemiol Biomarkers Prev; 27(6); 710–6. ©2018 AACR.

We report on a compact, stable, all-fiberized narrow-linewidth (0.045 nm) pulsed laser source emitting laser beam with a wavelength of 266 nm, and tunable pulse width and repetition rate. The system is based on all-fiberized nanosecond amplifier architecture, which consists of Yb-doped fiber preamplifiers and a super-large-mode-area Yb-doped fiber power amplifier. The fiber amplifier with a core of 50 μm is used to raise the threshold of the stimulated Brillouin scattering (SBS) effect and to obtain high output power and single pulse energy. Using lithium triborate (LBO) crystal and beta-barium borate (BBO) crystal for realizing the second-harmonic generation (SHG) and fourth-harmonic generation (FHG), we achieve 17 μJ (1.73 W) and 0.66 μJ (66 mW), respectively, at wavelengths of 532 nm and 266 nm and a repetition rate of 100 kHz with pulse width of 4 ns. This source has great potential applications in fluorescence research and solar-blind ultraviolet optical communication.

An orange–yellow emitting cationic iridium(III) complex [(ptpy)2Ir(BCP)]PF6 (ptpy: 2-(p-tolyl)pyridine; BCP: bathocuproine) was synthesized. [(ptpy)2Ir(BCP)]PF6 exhibited high thermal stability with the thermal decomposition temperature (T d) of 375 °C, with the temperature increasing from 20 to 100 °C, the photoluminescent intensity of [(ptpy)2Ir(BCP)]PF6 decreased to 79.9%. It can be efficiently excited by blue light (λmax = 457 nm) of GaN chip, and a series of GaN-based light-emitting diodes (LEDs) were fabricated by using it as phosphors blended in silicone at different blending concentrations. At 1.0 wt.%, a cold white LED was obtained, the corresponding color rendering index (CRI) was 77.1, correlated color temperature (CCT) was 6278 K, luminous efficiency (η L) was 68.4 lm W−1, and Commission Internationale de L’Eclairage (CIE) value was (0.32, 0.25). At 2.0 wt.%, a neutral white LED was obtained, the corresponding CRI was 74.2, CCT was 4737 K, η L was 75.4 lm W−1, and CIE value was (0.34, 0.27). At 2.5, 3.0, 4.0 and 5.0 wt.%, four warm white LEDs were obtained, among them, the maximum η L was 85.8 lm W−1 (at 4.0 wt.%), the maximum CRI was 73.7 (at 2.5 wt.%), their CCT changed between 3410 K and 2328 K, the CIE values were (0.37, 0.30), (0.41, 0.34), (0.46, 0.39) and (0.49, 0.41) respectively. The results suggest [(ptpy)2Ir(BCP)]PF6 is a promising phosphor candidate for white LEDs, especially for warm white LEDs.

An important issue in the construction of the basic theory on user experience is that user experience classification has not yet received a satisfactory answer. This makes it difficult for user experience researchers and designers to practice without clear recognition on research objects. This article points out the existing classification methods are inadequate to explain an independent and clear experience phenomenon. The key challenge lies in the current research methods are not suitable for the user experience task. To overcome it, we utilize a phenomenological method of inductive reasoning method to construct a new framework including 20 experience classification. In the qualitative research based on phenomenological methods, researcher’s own knowledge background tends to have an important impact on the quality and effectiveness of the research. The aim of this research is not trying to provide a once and for all solution, but make the applicability of phenomenological research methods applicable. The proposed framework can provide a possible platform for the discussion of experience classification issues.

Background As the last link in the chain of cardiovascular events, chronic heart failure (CHF) has high morbidity, high mortality, and poor prognosis. It is one of the main causes of death and disability worldwide. As a new drug for the treatment of chronic cardiovascular disease, dapagliflozin, the efficacy, and safety issues are still the focus of attention. Therefore, we conducted a meta-analysis to evaluate the efficacy and safety of dapagliflozin in the treatment of CHF. Methods According to the search strategy, regardless of publication date or language, randomized controlled trials (RCTs) of dapagliflozin for CHF will be retrieved from 8 databases. First of all, the literature was screened according to the eligibility criteria, and use the Cochrane Collaboration's tool to assess the quality of the included literature. Then, using Rev Man 5.3 and STATA 14.2 software for traditional meta-analysis. Finally, the evaluation of the quality of the evidence and the strength of the recommendations will adopt the Grading of Recommendations, Assessment, Development and Evaluation method. Results This study will evaluate the efficacy and safety of dapagliflozin for CHF, thereby providing more evidence support for clinical decision-making in CHF. Conclusion Our research will provide more references for the clinical medication of patients with CHF. Protocol registration number INPLASY202150046.

Coherent beam combination (CBC) is an effective method to break the limiting power of a single fiber laser. The Q-learning algorithm is one of the reinforcement learning algorithms. We use the Q-learning algorithm to do phase compensation in the field of CBC. The performance difference between the Q-learning algorithm and the stochastic parallel gradient descent optimization algorithm (SPGD) is analyzed by simulating time-domain coherent synthesis. The results show that the Q-learning algorithm is easier to debug and has better stability.

We report a linear-cavity mode-locked Yb-doped fiber laser using self-made semiconductor saturable absorber mirrors (SESAMs). The SESAMs are grown by means of metalorganic chemical vapor deposition, with a design of high modulation depth using strain-compensated multiple quantum wells. We choose two kinds of self-made SESAMs with different periods of top reflector in the linear cavity, and they can both be applied to stable mode-locking operation without damage. The output characteristics of the mode-locked oscillator indicate that SESAMs with high modulation depth are beneficial for mode-locked fiber lasers and the modulation depth can limit the pulse width of the output pulses.

We demonstrate an all-fiberized narrow-linewidth nanosecond amplifier with high peak power, tunable pulse width, and repetition rate. A fiber-coupled narrow-linewidth laser diode operating at 1064.1 nm is employed as the seed source, which is gain-switched to generate nanosecond pulses with tunable pulse widths of 1–200 ns and tunable repetition rates of 10 Hz–100 kHz. By utilizing a very-large-mode-area Yb-doped fiber with a core diameter of 50 μm in the power amplifier, thresholds of the stimulated Brillouin scattering at different pulse widths and repetition rates are increased. The maximum average power reaches 30.8 W at the pulse width of 4 ns and a repetition rate of 100 kHz, corresponding to an optical-to-optical conversion efficiency of ∼55.2%. Pulse energy and peak power are calculated to be 0.2 mJ and 50 kW, respectively, which are limited by stimulated Brillouin scattering. The 3-dB spectral linewidth remains around 0.05 nm during the power scaling process. The stimulated Brillouin scattering limited output powers at different pulse widths and repetition rates are investigated. Peak power of 47.5 kW (0.19 mJ) is obtained for the 4 ns pulses at a repetition rate of 50 kHz, which is nearly the same as that of 4 ns pulses at 100 kHz. When the pulse width of the seed source is increased to 8 ns, peak powers/pulse energies are decreased to 19.6 kW/0.11 mJ and 13.3 kW/0.08 mJ at repetition rates of 50 kHz and 100 kHz, respectively.

We propose a fiber-solid hybrid system which consists of a semiconductor saturable absorber mirror (SESAM) mode-locked fiber seed with a pulse width of 10.2 ps and a repetition rate of 18.9 MHz, a two-level fiber pre-amplifier and a double-passing end-pumped Nd:YVO4 amplifier. In the solid-state amplifier, to enhance the gain and the extraction efficiency, a specially designed structure in which the seed light passes through the gain medium four times and makes full use of population inversion is used as the double-passing amplifier. Besides, the beam filling factor (the ratio of the seed light diameter to the pump light diameter) and the thermal lens effect of the double-passing amplifier are considered and its optical-to-optical conversion efficiency is further improved. To preserve the beam quality of the double-passing amplifier, a new method of spherical-aberration self-compensation based on the principles of geometrical optics is used and discussed. Our system achieves a maximum average power of 9.5 W at the pump power of 28 W, corresponding to an optical-to-optical efficiency of 27%. And the beam quality factor M 2 reaches 1.3 at the maximum output power.

The invention of iPhone was a breakthrough in the mobile phone market, since then the values of user experience began to be widely realized. However, the basic theoretical construction of user experience is still incomprehensive. This has been a constraint on the effective implementation of UX studies and design practice for a long time. Clear classification of user experience is one of the theoretical problems to be solved. This study analyzes the emotional satisfaction mechanism reflected in various cases of purchase to define six experience categories which are utility experience, usability experience, aesthetic experience, novel experience, fashion experience, symbol experience. Their relationships and influence are also discussed. Each of these concepts specifies a range of practice for researchers while ensuring its independence. As a result, a systematic user experience classification system is established, which can assist UX investigators specifying their practice objects to effectively conduct their user study.

The increased popularity of social media and bid data development have led to online social commerce (OSC), in which users can take advantage of functionalities from both social network sites (e.g., "like" button in Facebook) and e-commerce platforms (e.g., payment tools in Amazon) to select products and make purchase decisions. Additionally, user can take advantage of big data generated from user content to make purchase decisions. This research-in-progress paper proposes a theoretical model, combining social tie strength, information technology affordances, and well-recognized e-commerce capabilities, to explore their combined effects. Therefore, we can further understand how users' product selection behavior is influenced by OSC. In this paper, we create an original instrument to measure the extent to which IT affordances are available, and adapt part of existing items to measure social tie strength by using a card sorting method and big data analysis. Future work and potential contributions are discussed.

This study aims to explore the application of storyboard and combination of storyboard and the technology of Internet of things (IoT) into the vehicle interactive design to improve deaf drivers’ experience. To achieve the aim, we introduced the storyboard approach into user need study and product prototype design, and practiced in the course of user experience at Beijing Union University. Our results show that the method has two benefits for students: 1. They can utilize storyboard to quickly understand the usage context of products without knowing the whole producing processes in real setting. 2. They can form future insights on the introduction of IoT into the vehicle interactive design, the deaf driving system, which has not been developed yet. This paper presents the approach in detail.

Background: Distinctive exosomal contents could be useful for cancer diagnosis and prognosis. However, little is known about whether serum exosomal heterogeneous nuclear ribonucleoprotein H1 (hnRNPH1) mRNA is a satisfactory biomarker for hepatocellular carcinoma (HCC). Methods: Two hundred and ninety-one participants divided into four age- and gender-matched groups, including a HCC group (n=88), a liver cirrhosis (LC) group (n=67), a chronic hepatitis B (CHB) group (n=68) and a healthy control group (n=68), were enrolled. Serum exosomal hnRNPH1 mRNA and GAPDH mRNA were measured using TaqMan real-time PCR, and the relative expression levels were calculated. Receiver operating characteristic (ROC) curves were constructed to evaluate the effectiveness of hnRNPH1 mRNA alone and in combination with α-fetoprotein (AFP) in the diagnosis of HCC. The correlation between hnRNPH1 mRNA levels and clinicopathological characteristics and overall survival (OS) in HCC was determined. Results: The serum exosomal hnRNPH1 mRNA levels in HCC patients were remarkably higher than in the other groups (phnRNPH1 mRNA discriminated HCC from CHB with an area under the ROC curve (AUC) of 0.865, with sensitivity of 85.2% and specificity of 76.5% at cut-off value of 0.670. The AUC for hnRNPH1 mRNA in combination with AFP was further improved. The exosomal hnRNPH1 mRNA levels in HCC patients were associated with the Child-Pugh classification, portal vein tumor emboli, lymph node metastasis, TNM stage and OS (p Conclusions: These findings suggested that serum exosomal hnRNPH1 mRNA could be an effective marker for HCC in high HBV prevalence areas.

Acoustic recordings of the environment provide an effective means to monitor bird species diversity. To facilitate exploration of acoustic recordings, we describe a content-based birdcall retrieval algorithm. A query birdcall is a region of spectrogram bounded by frequency and time. Retrieval depends on a similarity measure derived from the orientation and distribution of spectral ridges. The spectral ridge detection method caters for a broad range of birdcall structures. In this paper, we extend previous work by incorporating a spectrogram scaling step in order to improve the detection of spectral ridges. Compared to an existing approach based on MFCC features, our feature representation achieves better retrieval performance for multiple bird species in noisy recordings.

Bioacoustic data can be used for monitoring animal species diversity. The deployment of acoustic sensors enables acoustic monitoring at large temporal and spatial scales. We describe a content-based birdcall retrieval algorithm for the exploration of large data bases of acoustic recordings. In the algorithm, an event-based searching scheme and compact features are developed. In detail, ridge events are detected from audio files using event detection on spectral ridges. Then event alignment is used to search through audio files to locate candidate instances. A similarity measure is then applied to dimension-reduced spectral ridge feature vectors. The event-based searching method processes a smaller list of instances for faster retrieval. The experimental results demonstrate that our features achieve better success rate than existing methods and the feature dimension is greatly reduced.

Bioacoustic monitoring has become a significant research topic for species diversity conservation. Due to the development of sensing techniques, acoustic sensors are widely deployed in the field to record animal sounds over a large spatial and temporal scale. With large volumes of collected audio data, it is essential to develop semi-automatic or automatic techniques to analyse the data. This can help ecologists make decisions on how to protect and promote the species diversity. This paper presents generic features to characterize a range of bird species for bird vocalisation retrieval. In the implementation, audio recordings are first converted to spectrograms using short-time Fourier transform, then a ridge detection method is applied to the spectrogram for detecting points of interest. Based on the detected points, a new region representation are explored for describing various bird vocalisations and a local descriptor including temporal entropy, frequency bin entropy and histogram of counts of four ridge directions is calculated for each sub-region. To speed up the retrieval process, indexing is carried out and the retrieved results are ranked according to similarity scores. The experimental results show that our proposed feature set can achieve 0.71 in term of retrieval success rate which outperforms spectral ridge features alone (0.55) and Mel frequency cepstral coefficients (0.36).

Bioacoustic data can provide an important base for environmental monitoring. To explore a large amount of field recordings collected, an automated similarity search algorithm is presented in this paper. A region of an audio defined by frequency and time bounds is provided by a user; the content of the region is used to construct a query. In the retrieving process, our algorithm will automatically scan through recordings to search for similar regions. In detail, we present a feature extraction approach based on the visual content of vocalisations - in this case ridges, and develop a generic regional representation of vocalisations for indexing. Our feature extraction method works best for bird vocalisations showing ridge characteristics. The regional representation method allows the content of an arbitrary region of a continuous recording to be described in a compressed format.

In this paper, an automobile clutch comprehensive performance test platform is designed. By adjusting the size of the motor speed, torque and inertia torque plate and the road resistance, the working condition of the different models of clutch can be simulated, a variety of specifications clutch comprehensive performance of clutch can be test by using the single device. According to the big disturbance torque and high requirement of control accuracy, a fuzzy-PID control algorithm with Kalman filter was proposed for the rotational speed control. Based on the virtual instrument technology of National Instruments Corporation, the interface and data acquisition programs are developed. The results of simulation and experiment show that the accuracy and efficiency have been improved and the test platform is working stable and credible.

Background Gastric cancer is one of the most common malignant tumors in the world. Finding effective diagnostic biomarkers in urine or serum would represent the most ideal solution to detecting gastric cancer during annual physical examination. This study was to evaluate the potential of endothelial lipase (EL) as a urinary biomarker for diagnosis of gastric cancer. Methods The expression levels of EL was measured using Western blotting and immunohistochemical staining experiments on (tissue, serum, and urine) samples of gastric cancer patients versus healthy people. We also checked the EL levels in the urine samples of other cancer types (lung, colon and rectum cancers) and benign lesions (gastritis and gastric leiomyoma) to check if EL was specific to gastric cancer. Result We observed a clear separation between the EL expression levels in the urine samples of 90 gastric cancer patients and of 57 healthy volunteers. It was approximately 9.9 fold average decrease of the EL expression levels in the urine samples of gastric cancer compared to the healthy controls (P P = 0.90 and P = 0.79). In immunohistochemical experiments, positive expression of the EL protein was found in 67% (8/12) of gastric adjacent noncancerous and in 58% (7/12) of gastric cancer samples. There was no significant statistical in the expression levels of this protein between the gastric cancer and the matching noncancerous tissues (P =0.67). Conclusions The urinary EL as a highly accurate gastric cancer biomarker that is potentially applicable to the general screening with high sensitivity and specificity. Virtual Slides The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/4527331618757552