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The integrated technology acceptance model was proposed in 2003 and has been gradually applied in many fields since then. At present, the promotion of agricultural big data has achieved initial results, and a number of agricultural big data practice demonstration projects have been formed. For example, Shandong Province supports the establishment of the “Big Data Platform of Bohai Granary Science and Technology Demonstration Project,” which includes four modules of data collection, mining and analysis, monitoring and early warning, and decision-making service. It is characterized by the diversity of massive data sources, the integration of historical and real-time data, and multifactor comprehensive analysis and decision making. However, farmers, as an important service subject of agricultural big data platform, do not have strong willingness to participate. In the era of big data, it is still difficult for farmers to obtain data information and services, and their ability to obtain, screen, and use data is poor. Therefore, it is of great practical significance to effectively improve farmers’ willingness to adopt and use agricultural big data. Based on the integrated technology acceptance model, this study analyzed the impact of big data service of rural revitalization on farmers. Firstly, the basic content of integration technology acceptance theory was analyzed, and the research hypothesis was proposed based on this theory. After that, the questionnaire survey was used to empirically analyze the impact of big data service on farmers. Reliability and validity test, correlation test, goodness of fit test, and path system test were carried out on the analysis results to prove the factors that affect farmers’ behavior and attitude of using big data.

Amino acids are one of the main metabolites in the body, and provide energy for the body and brain. The purpose of this study is to provide a profile of amino acid changes in the serum of patients with Moyamoya disease (MMD) and identify potential disease biomarkers. In this paper, we quantitatively determined the serum amino acid metabolic profiles of 43 MMD patients and 42 healthy controls (HCs). T test, multivariate statistical analysis, and receiver operating characteristic (ROC) curve analysis were used to identify candidate markers. Thirty-nine amino acids were quantified, and 12 amino acid levels differed significantly between the MMD patients and HCs. Moreover, based on ROC curve analysis, four amino acid (L-methionine, L-glutamic acid, β-alanine and o-phosphoserine) biomarkers showed high sensitivity and specificity (AUC > 0.90), and showed the best sensitivity and specificity in MetaboAnalyst 5.0 using binary logistic regression analysis. We have provided serum amino acid metabolic profiles of MMD patients, and identified four potential biomarkers which may both provide clinicians with an objective diagnostic method for early detection of MMD and further our understanding of MMD pathogenesis.

Fiber deformation measurement is crucial in the structure health monitor, which reflects the stress, strain or deformation of the structure where the fiber is laid. The principle of the fiber deformation measurement by the optical phase tracking in OFDR scheme is described and the data processing algorithm is demonstrated in details to receive accurate results. The differential phase is acquired by making a difference between the phase spectrum of the reference and measurement states. A robust phase unwrapping method based on the density distribution is proposed to get the whole unwrapped low-noise phase of the fiber. Additionally, the phase decoherence caused by the scatter unit misalignment induced by the fiber deformation is analyzed and the phase correction method is proposed to improve the phase coherence. The fiber deformation can be tracked along the fiber with a resolution of tens of microns, depending on the set parameters of the OFDR system. Moreover, the strain distribution is also derived from the differential phase. In the experiments, the measurements of the standard single-mode fiber with uniform and non-uniform deformation have been accomplished in a spatial resolution of 40 μm. The noise is about 0.1 μm in a stretching range of about 40 μm. Simultaneously, hundreds of microstrain are obtained and show a high accuracy with a resolution of the level of millimeter.

Electronegative guests can be induced to fill the voids of skutterudite by doping electron donors in the framework of skutterudites. This method has been considered a promising method to improve thermoelectric properties. In this study, SeyNi0.3Co3.7Sb12 (y = 0, 0.025, 0.1, 0.125, 0.15) skutterudite compounds were prepared using a melt-quenching-annealing synthesis route and spark plasma sintering technology. The phase constituents, microstructure, thermoelectric properties, and thermal transport properties were investigated. Experimental results suggest that the charge compensation between Ni doping and Se filling has a positive effect on the formation of thermodynamically stable SeyNi0.3Co3.7Sb12 alloys. The existence of Se fillers in the voids reduces the lattice thermal conductivity. As the filling fraction of Se increases, the number of holes increases while the electron concentration decreases. The figure of merit (zT) of Se0.15Ni0.3Co3.7Sb12 reaches a maximum of 0.81 at 823 K.

In this study, a series of potential candidate molecules with excellent antitumor activity targeting tubulin and PTEN/PI3K/Akt signaling pathway was synthesized by modifying the molecule structure of podophyllotoxin (PPT) at the C-4 position via a structure-guided drug design approach. MTT assay results indicated that compound 12c had stronger anti-proliferative activities against HGC-27, MCF-7 and H460 cell lines than etoposide (VP-16), especially for HGC-27 (12c: IC

To achieve high-performance thermoelectric (TE) devices, constructing a good interfacial connection between TE materials and electrodes is as important as having high figure-of-merit TE materials. Although CoSb3-based TE devices have received great attention for power generation recently, the limited long-term service stability is the main obstruct for their applications. In this work, we have prepared two kinds of Ti-based alloys (Ti83.7Al10.7Si5.6 and Ti74Ni26) as the diffusion barrier layer of CoSb3-based TE joints by the spark plasma sintering method and have systematically investigated their interfacial behaviors during the aging process. The performances of contact resistivity and mechanical strength for Ti74Ni26/Yb0.4Co3.8Fe0.2Sb12 TE joints are good before aging treatment but gradually deteriorate during the aging process, which should be ascribed to the phase-transition-induced negative thermal expansion in Ti-Ni alloys. On the other hand, Ti83.7Al10.7Si5.6/Yb0.4Co3.8Fe0.2Sb12 TE joints show both low contact resistivity ( 20 MPa) before and after 16-day aging at 500 °C, which is originated from the matching of the coefficient of thermal expansion (CTE) and the formation of network structures in Ti-Al-Si alloys. We have also prepared an eight-couple TE module of p-Ge0.9Sb0.1TeB0.01/n-Yb0.4Co3.8Fe0.2Sb12 and have measured its corresponding device performance. Our work has demonstrated that the matched CTE and network structures in the Ti-Al-Si alloy are key to obtain high-performance CoSb3-based TE joints for long-term service.

We present a method for learning a function over distributions. The method is based on generalizing nonparametric kernel regression by using the earth mover’s distance as a metric for distribution space. The technique is applied to the problem of learning the dependence of pitcher performance in baseball on multidimensional pitch distributions that are controlled by the pitcher. The distributions are derived from sensor measurements that capture the physical properties of each pitch. Finding this dependence allows the recovery of optimal pitch frequencies for individual pitchers. This application is amenable to the use of signatures to represent the distributions and a whitening step is employed to account for the correlations and variances of the pitch variables. Cross validation is used to optimize the kernel smoothing parameter. A set of experiments demonstrates that the new method accurately predicts changes in pitcher performance in response to changes in pitch distribution and also outperforms an existing technique for this application.

Sb2S3/perylene diimide derivatives composite micro-spheres composed of slight dendrites were synthesized by solvothermal reaction. Perylene diimide derivative with two carboxyl groups at amine position as morphology-controlling reagent is the key factor for determining the microscopic morphology of Sb2S3 in this system. Time-dependent experiments have been conducted to track the formation of Sb2S3 micro-spheres. Moreover, the composite material showed an excellent sensitivity of 29.8 μA mM−1 cm2 with a low detection limit of 50 pM, it also showed better stability and selectivity in hydrazine detection. This approach not only regulate the morphology and composition of Sb2S3 submicron materials effectively, but also provide new ideas for the manufacture of metal sulfide- perylenediimide amino acid derivative materials, which will be suitable for sensing, catalysis, and photovoltaic applications.

How to improve the enantiomer separation efficiency of drugs is a hot topic. In this paper, polydopamine (PDA) coating doped with graphene oxide (GO) by physical adsorption was used to modify the capillary column to enhance the enantioseparation efficiency of the drugs. In the capillary electrochromatography (CEC) system, the novel capillary column with carboxymethyl-β-cyclodextrin (CM-β-CD) as a chiral selector has completed the enantioseparation of four basic drugs (propranolol, metoprolol, amlodipine and chlorpheniramine). The optimum separation conditions were obtained by optimizing the pH of the buffer, the concentration of organic modifier, the concentration of the chiral selector and the voltage, and the resolution and peak shape were significantly improved compared with uncoated bare-fused column. The stability and reproducibility of the new capillary column were satisfactory and the relative standard deviation of intra-day and inter-day was

Objects Caloric restriction (CR) is known to extend lifespan and exert a protective effect on organs, and is thus a low-cost and easily implemented approach to the health maintenance. However, there have been no studies that have systematically evaluated the metabolic changes that occur in the main tissues affected by CR. This study aimed to explore the target tissues metabolomic profile in CR mice. Methods Male C57BL/6J mice were randomly allocated to the CR group (n = 7) and control group (n = 7). A non-targeted gas chromatography–mass spectrometry approach and multivariate analysis were used to identify metabolites in the main tissues (serum, heart, liver, kidney, cortex, hippocampus, lung, muscle, and white adipose) in model of CR. Results We identified 10 metabolites in the heart that showed differential abundance between the 2 groups, along with 9 in kidney, 6 in liver, 6 in lung, 6 in white adipose, 4 in hippocampus, 4 in serum, 3 in cortex, and 2 in muscle. The most significantly altered metabolites were amino acids (AAs) (glycine, aspartic acid, l-isoleucine, l-proline, l-aspartic acid, l-serine, l-hydroxyproline, l-alanine, l-valine, l-threonine, l-glutamic acid, and l-phenylalanine) and fatty acids (FAs) (palmitic acid, 1-monopalmitin, glycerol monostearate, docosahexaenoic acid, 16-octadecenoic acid, oleic acid, stearic acid, and hexanoic acid). These metabolites were associated with 7 different functional pathways related to the metabolism of AAs, lipids, and energy. Conclusion Our results provide insight into the specific metabolic changes that are induced by CR and can serve as a reference for physiologic studies on how CR improves health and extends lifespan.

Dadi Xie,1,* Fengfeng Li,1,* Deshui Pang,1 Shiyuan Zhao,2 Meihua Zhang,1 Zhongfa Ren,1 Chunmei Geng,2 Changshui Wang,3 Ning Wei,4 Pei Jiang2 1Tengzhou Central People’s Hospital, Tengzhou, 277500, People’s Republic of China; 2Jining First People’s Hospital, Jining Medical University, Jining, 272000, People’s Republic of China; 3Affiliated Hospital of Jining Medical University, Jining Medical University, Jining, 272000, People’s Republic of China; 4Shanting District People’s Hospital, Zaozhuang, 277200, People’s Republic of China*These authors contributed equally to this workCorrespondence: Meihua ZhangTengzhou Central People’s Hospital, Xingtan Road, Tenzhou, 277500, People’s Republic of ChinaTel/Fax +86 0632-5512227Email meihua_zhang@126.comPei JiangJining First People’s Hospital, Jning Medical University, Jiankang Road, Jining, 272000, People’s Republic of ChinaTel/Fax + 86 0537-2106208Email jiangpeicsu@sina.comPurpose: Inflammatory bowel diseases (IBD) are a chronic inflammatory disease, which affects almost all tissues in the body. Previous studies mainly focused on breathing, fecal, and urine samples of patients with IBD. However, there is no comprehensive metabolomic analysis of the serum, colon, heart, liver, kidney, cortex, hippocampus, and brown fat tissues. Therefore, the aim of our study is to evaluate the utility metabolomic analysis of target tissues in the pathogenesis of IBD in exploring new biomarkers for early diagnosis and treatment.Methods: Male Sprague–Dawley rats were randomly allocated to control and DSS-treated groups (n = 7). Dextran sulfate sodium (DSS) was orally administered for 6 weeks. Gas chromatography-mass spectrometry (GC-MS) was used for metabolite determination, multivariate statistical analysis was used to identify metabolites that were differentially expressed in two groups.Results: Our results showed that 3, 11, 12, 6, 5, 13, 13, and 11 metabolites were differentially expressed between the DSS treatment group and the control group in the serum, colon, heart, liver, kidney, cortex, hippocampus, and brown fat tissues, respectively. The most significant change of metabolites in the study was amino acid (L-alanine, L-glutamic acid, L-phenylalanine, L-proline, L-lysine, L-isoleucine, L-tryptophan, L-norleucine, L-valine, glycine, serine, L-threonine), organic acid (citric acid, 3-hydroxybutyric acid, propanoic acid), glucide (D-arabinose, D-fructose) and purine (9H-purin-6-ol, D-ribose) profiles. Several pathways were affected according to the integrated pathway analysis. These pathways ranged from amino acid metabolism (such as alanine, aspartate, and glutamate metabolism, glutathione metabolism) to purine metabolism (aminoacyl-tRNA biosynthesis).Conclusion: Using GC-MS-based profiling of metabolite changes, these results may provide a more comprehensive view for IBD and IBD-related diseases and improve the understanding of IBD pathogenesis.Keywords: inflammatory bowel disease, metabolite, GC-MS, dextran sodium sulfate, biomarker

We semianalytically and numerically investigate the static and dynamical characteristics of quantum-dot (QD) lasers directly grown on silicon by considering the Shockley-Read-Hall (SRH) recombination. The static characteristics are studied through small-signal analysis, including the ${\ensuremath{\alpha}}_{H}$ factor, damping factor, and modulation dynamics. In addition, the feedback dynamics are analyzed through improved corpuscular rate equations based on the classical Lang-Kobayashi (LK) model with time series, bifurcation diagrams, and phase portraits. We find that a smaller ${\ensuremath{\alpha}}_{H}$ factor but larger damping factor are obtained by decreasing the nonradiative recombination lifetime. On top of that, in both the short- and long-external-cavity regimes, any decrease of the SRH recombination lifetime obliterates significantly chaotic regions and shifts the first Hopf bifurcation point to higher feedback values. Overall, this work provides insights into the understanding of QD laser physics, hence highlighting the influence of the SRH lifetime on the reflection sensitivity of epitaxial QD lasers on silicon. These results are qualitatively consistent with recent experiments and are therefore helpful for designing feedback-resistant lasers for future photonic integrated circuits operating without optical isolation.

The renin-angiotensin system (RAS) helps to regulate cardiovascular function, the maintenance of electrolyte and fluid balance, and blood pressure. The RAS contains two axes; the angiotensin-converting enzyme/angiotensin II/Ang II type 1 receptors (ACE/Ang II/AT1) classic axis, which has a role in regulating blood pressure, vascular oxidative stress, coagulation, and cellular proliferation. The other is the angiotensin-converting enzyme 2/angiotensin-(1-7)/Mas receptors (ACE2/Ang-(1-7)/Mas) axis, which can inhibit the former axis, improve fat metabolism, reduce inflammation and oxidative stress, and enhance glucose tolerance and insulin sensitivity. The ACE2/Ang-(1-7)/Mas axis is found in blood vessels, kidneys, liver, pancreas and the brain. It can protect the body from abnormalities in glucose metabolism. The ACE2/Ang-(1-7)/Mas axis can enhance glucose tolerance and improve insulin sensitivity by protecting pancreatic β cells, increasing insulin secretion, improving glucose metabolism in adipose tissue, enhancing glucose uptake by skeletal muscle, and inhibiting hepatic gluconeogenesis. This article reviews the main characteristics and functions of the ACE2/Ang-(1-7)/Mas axis and its regulation of glucose metabolism in order to demonstrate its potential as a target for the treatment of metabolic diseases such as diabetes.

Spectrum registration and spatial calibration are presented and demonstrated in optical frequency domain reflectometry based sensing system for achieving a wide strain measurement range. In both dynamic and static measurement case, the feasibility of the proposed method is evaluated. First, spectrum registration is demonstrated to demodulate strain value, which increases the data acquisition rate dozens of times and also keep the high measurement range. A measurement rate up to 800 Hz is achieved. Second, the general difficulty in large strain measurement is analyzed. The combination of spatial calibration and spectrum registration is, therefore, proposed to reduce the mismatch of the spatial segments in the case of large strain variation. The local measurement spectrum segment extracted by a narrow box window for spectrum registration is proposed to maintain a high spatial resolution. Strain exceeding 7000 μe is demodulated with a gauge length of 5 mm accurately. Finally, graphic processing unit (GPU) technology is used to accelerate the data processing rate in the demodulation process, which makes it more hopeful for the practical application.

In this contribution, we report a significant enhancement of thermoelectric properties of Sn0.5Ge0.4875Te alloy through three synergistic effects with Pb alloying: the significant reduction of the lattice thermal conductivity of the high entropy alloy (HEA) main phase (Sn, Ge, Pb)Te and lamellae microstructures produced from the spinodal decomposition in the alloy; the significant reduction of the carrier thermal conductivity and the significant increases of the Seebeck coefficient by decreasing the carrier concentration with Pb alloying. The high entropy random solid solution (Sn, Ge, Pb)Te single phase with NaCl-type structure forms in the alloys (Sn0.5Ge0.4875)1-xPbxTe with x = 0.2 and 0.8, while the minor cubic GeTe-based phase arises in the (Sn, Ge, Pb)Te matrix in the alloys with x = 0.33, 0.5 and 0.6, forming the lamellae microstructures. All alloys keep p-type conduction. The hole concentration decreases, but carrier mobility increases and carrier thermal conductivity decreases with Pb content x increasing. The thermoelectric properties of the alloys can be enhanced significantly with synergistic effects with proper Pb alloying. We eventually obtained the maximum figure of merit ZT of 1.61 at 773 K in the alloy (Sn0.5Ge0.4875)1-xPbx with x = 0.5.

Achieving highly efficient blue emitters at high luminance with nondoped structure is a crucial issue in the field of commercial full-color organic light-emitting diodes (OLEDs). In this paper, we designed and synthesized three novel blue materials PIAnTAZ, TPAAnTAZ and CzAnTAZ by utilizing anthracene as the primary acceptor, triazine as the assistant acceptor and phenanthroimidazole/triphenylamine/carbazole as the donor. The nondoped device based on the PIAnTAZ emitter exhibits blue electroluminescence with an emission peak at 468 nm, a maximum luminance over 50 000 cd m−2 and a maximum external quantum efficiency (EQE) of 7.96%. More importantly, the nondoped device exhibits an ultra-low efficiency roll-off of 7.90% at a high luminance of up to 1000 cd m−2; even at a brightness of 10 000 cd m−2, the EQE can still remain as high as 6.49%. This work provides a new insight into the design of high-efficiency OLEDs at high luminance with simple device structure for further practical applications.

A theoretical model is established for estimating the strain measurement error based on the Rayleigh backscattering spectrum correlation in distributed optical fiber strain measurements. Assuming the signal is much larger than the noise, the theoretical model predicts the strain measurement error using noise variance and the defined quality factor Q of the Rayleigh backscattering spectrum. Furthermore, an algorithm based on the quality factor Q is proposed to select an optimized sliding-window. The sliding-window length can be obtained by calculating the threshold value of the quality factor using a theoretical model corresponding to the required strain measurement accuracy. Compared with the traditional method where the sliding-window length is defined by the user based on spatial resolution requirements or an empirical definition, the sliding-window length determined by the algorithm is more reasonable and can be automatically defined, alleviating the requirement for user inputs. To verify the correctness of the theoretical model, two experiments are set up: a self-correlation experiment, that analyzes the effect of the quality factor on the strain measurement accuracy, and a virtual experiment of the noise influence, which analyzes the effect of different noise variances. The experimental results are in good agreement with those of the model.

Photonics integrated circuits on silicon are considered as a key technology for data centers and high-performance computers. Owing to the ultimate carrier confinement and reduced sensitivity to crystalline defects, semiconductor quantum dot lasers directly grown on silicon exhibit remarkable properties such as low threshold current, high temperature stability and robust tolerance to external reflections. This latter property is particularly important for achieving large-scale integrated circuits whereby unintentional back-reflections produced by the various passive/active optoelectronic components can hinder the stability of the lasers. In this context, it is known that quantum dot lasers are more resistant to optical feedback than quantum well ones thanks to the low linewidth enhancement factor, the large damping, and the possible absence of upper lasing states. In this work, we theoretically investigate the reflection sensitivity of quantum dot lasers directly grown on silicon by studying the peculiar role of the epitaxial defects, which induce nonradiative recombination through the Shockley-Read-Hall process. By using the Lang and Kobayashi model, we analyze the nonlinear properties of such quantum dot lasers through the bifurcation diagrams and with respect to the nonradiative lifetime. In particular, we show that the increase of the Shockley-Read-Hall recombination shrinks the chaotic region and shifts the first Hopf bifurcation to higher feedback values. We believe that these results can be useful for designing novel feedback resistant lasers for future photonics integrated circuits operating without optical isolator.

Quantum dot lasers directly grown on silicon are excellent candidates to achieve energy and cost-efficient optical transceivers thanks to their outstanding properties such as high temperature stability, low threshold lasing operation, and high feedback tolerance. In order to reach even better performance, p-type doping is used to eliminate gain saturation, gain broadening due to hole thermalization and to further reduce the linewidth enhancement factor. Optical transceivers with low relative intensity noise are also highly desired to carry broadband data with low bit-error rate. Indeed, the intensity noise stemming from intrinsic optical phase and frequency fluctuations caused by spontaneous emission and carrier noise degrades the signal-to-noise ratio and the bit-error rate hence setting a limit of a highspeed communication system. This paper constitutes a comprehensive study of the intensity noise properties of epitaxial quantum dot lasers on silicon. Results show minimal values between - 140 dB/Hz and - 150 dB/Hz for doping level between 0 and 20 holes/dot in the active region. In particular, the intensity noise is insensitive to temperature for p-doped QD laser. Modulation properties such as damping, carrier lifetime, and K-factor are also extracted from the noise characteristics and analyzed with respect to the doping level. We also provide numerical insights based on an excitonic model illustrating the effects of the Shockley-Read-Hall recombination on the intensity noise features. These new findings are meaningful for designing high speed and low noise quantum dot devices to be integrated in future photonic integrated circuits.

Acrylamide (ACR) is a widely used environmentally hazardous compound that is known to be neurotoxic, genotoxic, carcinogenic, and reproductive toxicity. It is widely present in soil, water, agents used in chemical industries, and food. It can be distributed to all organs and tissues, and can cause damage to various human systems and those of other animals. Previous metabolomics studies have mainly focused on metabolites in serum and urine, but have lacked comprehensive analysis of major organs and tissues. In the current study, a gas chromatography-massspectrometry method was used to investigate mechanisms underlying organ toxicity, in an effort to identify potentially sensitive biomarkers in the main target tissues of rats after ACR exposure. Male Sprague-Dawley rats were assigned to two groups; a control group and a group treated with 20 mg kg−1 ACR intragastrically for 6 weeks. Metabolite changes in the two groups were statistically analyzed. The respective numbers of altered metabolites in the hippocampus, cortex, kidney, serum, heart, liver, and kidney fat were 21, 21, 17, 5, 15, 14, and 6. There were 14 metabolic pathways related to amino acid, fatty acid, purine, and energy metabolism, revealing that the toxic mechanism of ACR may involve oxidative stress, inflammation, and amino acid metabolism and energy disorders.

Chaos in nonlinear dynamical systems is featured with irregular appearance and with high sensitivity to initial conditions. Near-infrared semiconductor lasers subject to optical feedback from an external reflector are popular chaotic light sources, which have enabled multiple applications. Here, we report the fully-developed chaos in a mid-infrared interband cascade laser with external optical feedback. The chaos leads to significant electrical power enhancement over a frequency span of 500 MHz. In addition, the laser also exhibits periodic oscillations or low-frequency fluctuations before producing chaos, depending on the operation conditions. This work paves the way for extending chaos investigations from the near-infrared regime to the mid-infrared regime, which can stimulate potential applications in this spectral range.