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The number of diabetes specialist nurse as well as their knowledge and skills have increased in Gansu Province since 2017. However, China has not fully addressed how to improve their professional skills to deliver effective health education. To investigate the knowledge, skills, and personal attributes of competent health education practices among diabetes specialist nurses in Gansu Province, western China, and the potential influencing factors. Cross-sectional study. In total, 178 diabetes specialist nurses from 45 hospitals participated in this study. Data were collected between December 2022 and April 2023 using the Nurse Health Education Competence Instrument (I-CepSE) and a self-report questionnaire. Descriptive and inferential statistics, including univariate and multiple linear regression analyses, were used to analyze data. The mean scores of overall I-CepSE, knowledge, skills, and personal attributes were 218.77 ± 31.65, 77.80 ± 18.27, 103.95 ± 13.75 and 37.02 ± 4.73, respectively. A shortage of nursing staff and heavy workload (81.4 %), lack of cooperation from patients (56.5 %), lack of access to educational resources during work placement (54.2 %), and nurses' lack of knowledge/skills in health education (53.1 %) were common barriers to health education implementation. The regression models for the overall health education competence domain were significant (P < 0.001) with R2 values ranging from 31.9 % to 50.5 %. Education level and years of experience in diabetes-related care were found to be significant on all knowledge, skills, and personal attitude scales (P < 0.05), and age was associated with diabetes specialist nurses' skills and personal attitude scores (P < 0.05). Diabetes specialist nurses demonstrated moderate to high levels of health education knowledge, skills, and attitudes. However, they lacked knowledge of pedagogical techniques and resources, with inadequate educational skills. This study suggests that reasonable nursing human resource allocation and continuous education and training are crucial for improving health education competence. • Data concerning diabetes specialist nurses' health education competence is unknown. • Diabetes specialist nurses reported upper-middle levels of health education competence. • Reasonable nursing human resources allocation and continuous education are key. [ABSTRACT FROM AUTHOR]

• A new time-domain-based energy-oriented spacing policy is proposed. • Discrete-time vehicle platoon system integrating communication delay and disturbance is provided. • Less conservative discrete robust platoon control methodology is developed. • L 2 -based string stability and its criterion of the discrete platoon are given. This paper presents a discrete control framework for a homogeneous vehicle platoon, which can minimize the energy consumption of each vehicle while ensuring the platoon string stability under external interference and communication delay. First, a novel variable spacing strategy named as the energy-oriented spacing policy is proposed by comparing the geometry relationship of each vehicle which drives at energy-optimal speed and the ideal speed under the constant spacing policy. Then, based on the energy-oriented spacing policy, the dynamics of a homogeneous discrete vehicle platoon composed of several pure electric vehicles are built, including the communication delay and external disturbance. Second, a discrete robust platoon controller that can reduce the conservatism of the control system is designed based on the Lyapunov-Krasovskii theorem and H ∞ method, which drives each vehicle at their energy-optimal speed while ensuring the string stability of platoon under communication delays and interferences. Third, the L 2 -based string stability of the discrete platoon is defined, and its string-stable criterion is given under communication delays and external disturbances. Simulation results indicate that the proposed energy-oriented spacing policy and the discrete controller can enable efficient driving of each vehicle while ensuring the platoon string stability. The energy consumption of the whole platoon is, respectively, reduced by 7.3% and 5.7% compared to the vehicle platoon controllers with constant spacing policy and constant time headway policy. [ABSTRACT FROM AUTHOR]

Abstract In the finite element and boundary element coupling method, the Stekhlov–Poincaré mapping is often adopted at the coupling boundary, i.e., the unknown Neumann data are represented by the unknown Dirichlet data on the same boundary. This coupling method (either by a convolution integral, or by a Fourier series) is referred as the conventional method. We propose an alternative method, where the unknown Dirichlet data at the boundary are represented by the unknown solution value on an interior curve or surface, i.e., a Dirichlet-to-Dirichlet (D-to-D) mapping is employed instead of a Dirichlet-to-Neumann (D-to-N) mapping. The convergence of the method is shown to be of optimal order. 2D and 3D numerical experiments are performed to demonstrate the accuracy of the proposed method, comparing to the two conventional D-to-N coupling methods. [ABSTRACT FROM AUTHOR]

Noninvasive and accurate assessment of driving fatigue in relation to brain activity during long-term driving can contribute to traffic safety and accident prevention. This study evaluated functional connectivity (FC) in relevant brain regions. Synergistic mechanisms in different brain regions were detected by a novel simulator, which combined semi-immersive virtual reality technology and functional near-infrared spectroscopy. Each subject was instructed to complete driving tasks coupled with a mental calculation task. Wavelet coherence (WCO) and wavelet phase coherence (WPCO) were calculated and assessed in frequency intervals (I) 0.6–2 and (II) 0.145–0.6 Hz as global connectivity measures; (III) 0.052–0.145, (IV) 0.021–0.052, (V) 0.0095–0.021 and (VI) 0.005–0.0095 Hz as FC. WCO and WPCO revealed the strength and synchronization of cerebral connectivity, respectively. Significantly low WCO levels were found in intervals I and III in prefrontal cortex (PFC) and IV in motor cortex (MC) at the end of the driving task. Furthermore, significantly low WPCO were found in intervals I, and III in PFC and interval IV in MC. Experimental findings suggested that progressive mental fatigue adversely influences the cognitive function in the PFC and the cooperative mechanism between the PFC and MC. [ABSTRACT FROM AUTHOR]

A true random number generator (TRNG) is a fundamental security primitive. Recently, the semiconductor superlattice (SSL) has been investigated as an ideal physical entropy source with high speed. It shows multi-degree freedom nonlinearity based on the effects of quantum mechanics. However, there is still a lack of systematic evaluation schemes for SSL. In this study, a chaotic assessment model for SSL is proposed. Chaotic characteristic assessment and nonlinear dynamics estimation are carried out using the model. Furthermore, a set of entropy estimation procedures are introduced to evaluate the uncertainty of the SSL. The estimation results demonstrate that SSL is chaotic, highly complex, and nonlinear. SSL shows stable performance and has an entropy rate greater than 50% with 8 sample bits. Moreover, the throughput of the assessment prototype reaches 300 Mbit/s. In brief, SSL is an excellent physical entropy source for high-quality and high-speed TRNG. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we reduce the classical two-dimensional transmission problem in acoustic scattering to a system of coupled boundary integral equations (BIEs), and consider the weak formulation of the resulting equations. Uniqueness and existence results for the weak solution of corresponding variational equations are established. In contrast to the coupled system in Costabel and Stephan (1985) , we need to take into account exceptional frequencies to obtain the unique solvability. Boundary element methods (BEM) based on both the standard and a two-level fast multipole Galerkin schemes are employed to compute the solution of the variational equation. Numerical results are presented to verify the efficiency and accuracy of the numerical methods. [Copyright &y& Elsevier]

An implicit Galerkin meshfree scheme based on the element-free Galerkin (EFG) and the backward Euler methods is analyzed for general second-order parabolic problems. The penalty method is used to impose Dirichlet boundary conditions, and a priori approximation error has been derived to confirm its validity. The existence and uniqueness of the weak solution for the penalized parabolic problems under homogeneous mixed boundary conditions are proved, offering an insight for numerical discretizations. With an orthogonal projection being defined, the continuous error bounds with the penalty factor for the semi-discrete approximation are obtained, and meanwhile, the discrete error bounds with the penalty factor for the fully discrete approximation are also achieved, which provide a theoretical explanation for the value of a reasonable penalty factor. Finally, numerical examples are conducted to verify the theoretical results. [ABSTRACT FROM AUTHOR]

A free-running Fe:ZnSe laser is demonstrated under the pump of a single-shot 2.94 μm Er:YAG laser along the cavity axis at liquid nitrogen temperature of 77 K. At the incident pump energy of 1.47 J, a maximum single pulse energy of 253.7 mJ is obtained with a minimum pulse duration of 92.4 μs, corresponding to a slope efficiency of 16.2%. The central wavelength and the full width at half maximum (FWHM) are 3944.7 and 68.4 nm, respectively. [ABSTRACT FROM AUTHOR]

Abstract: A novel and simple fluorescent chemosensor based on rhodamine was designed and synthesized to detect Hg2+ with high selectivity. The structure of chemosensor 1 was characterized by IR, 1H NMR, and HRMS spectroscopies. Chemosensor 1 exhibited distinct fluorescent and colorimetric changes toward Hg2+ in an ethanol/water (80/20, v/v) solution, which resulted in the formation of 1/Hg2+ complex with the Hg2+-induced ring opening of the spirolactam ring in rhodamine. The reversibility of chemosensor 1 was verified through its spectral response toward Hg2+ ions and TBAI (tetrabutylammonium iodide) titration experiments. [Copyright &y& Elsevier]

With the pump of a KTP optical parametric oscillator (OPO) at 1150 nm, a gain-switched Ho,Pr:LLF laser was experimentally demonstrated in this paper. The maximum single pulse energy of 98.8 μJ with the minimum pulse width of 22 ns was achieved at the pulse repetition frequency (PRF) of 1 Hz, corresponding to a peak power of 4.5 kW. The central wavelength of the gain-switched laser was 2958 nm with a full width at half maximum (FWHM) of 4.5 nm. [ABSTRACT FROM AUTHOR]

Garlic ( Allium sativum L.) is cultivated by extensive vegetative propagation, which may lead to germplasm degradation, the accumulation of various viruses, a low propagation coefficient, and high production costs. Tissue culture is the most effective method for the rapid propagation and germplasm enhancement of virus-free garlic. Here, we present a system for producing tissue culture garlic using inflorescences of Baodi garlic ‘Liu Ban Hong’ as explants. By optimizing the type and concentration of plant growth regulators, as many as 11 adventitious buds could be produced from one explant. The propagation coefficient of bulblets in vitro could reach 10.64 per explant after optimization of the culture approach and induction parameters. Additionally, tissue culture garlic was shown to achieve a certain virus elimination effect by ELISA. In this study, we present a complete system for producing virus-free Baodi garlic from explants. This system provides important technical support for eliminating viruses, increasing propagation efficiency, maintaining genetic stability, and improving the quality of garlic. [ABSTRACT FROM AUTHOR]

Postural instability and falls are commonly seen because of aging and motor disabilities. This study aims to assess the posture-related changes in brain functional connectivity by wavelet phase coherence (WPCO) of oxyhemoglobin concentration change (Δ[HbO 2 ]) signals measured through near-infrared spectroscopy (NIRS) in elderly subjects. The NIRS signals were continuously recorded from the prefrontal cortex and sensorimotor cortical areas in 39 healthy elderly subjects and 22 young healthy subjects during 20 min resting and 10 min standing states. Eight connection types were obtained from the recorded brain areas. The WPCO were calculated in five frequency intervals in each channel pair as follows: I, 0.6–2 Hz; II, 0.145–0.6 Hz; III, 0.052–0.145 Hz; IV, 0.021–0.052 Hz; and V, 0.0095–0.021 Hz. Results show that posture change and age significantly interacts with the right prefrontal cortex (PFC) and left sensorimotor cortex (SMC) connectivity in interval V (F = 5.010, p = 0.028). The left and right PFC connectivity in interval I, the left and right SMC connectivity in interval IV, and the connectivity in interval V, including right PFC and right SMC connectivity, left PFC and left SMC connectivity, and right PFC and left SMC connectivity, showed a significant difference between the Group Elderly and Group Young in response to posture change (p < 0.05). This study provides new insight into the mechanism of posture control, and results may be useful in assessing the risk of postural instability in aged persons. [ABSTRACT FROM AUTHOR]

• An eco-driving control strategy is proposed for vehicles approaching a signalized intersection. • The discharge of the vehicle queue is modeled and predicted. • The proposed strategy is based on a computationally efficient iterative dynamic programming algorithm. • Monte-Carlo simulation using real-world traffic data is performed for in-depth energy efficiency analysis. • Energy-saving potential enabled by the proposed strategy is investigated for both internal combustion engine and electric vehicles. This paper takes into consideration of vehicle queues at the intersection and proposes an energy-efficient driving strategy to improve vehicle energy efficiency and overall traffic throughput in an urban traffic environment. The proposed strategy is applicable for both electric vehicle and internal combustion engine vehicle, and the control framework is formed by three sections, a vehicle queue discharge predictor, a spatial-domain optimal control strategy for energy consumption minimization, and a speed tracker with consideration of collision avoidance constraints. The former is based on the intelligent driver model, which predicts an accurate vehicle queue discharge time. Then the iterative dynamic programming is utilized to find the optimal solutions with fast computational speed. Finally, the optimal speed profile is followed by a Proportion-Integration controller while keeping a safe inter-vehicular distance. A Monte-Carlo simulation is designed to evaluate the energy efficiency of the proposed strategy in the stochastic traffic environment. Compared to the regular eco-approach and departure and constant speed strategies that lack awareness of the queue, significant energy saving can be achieved of the proposed strategy. In addition, three typical cases are selected to study the energy efficiency when the proposed strategy is applied to internal combustion engine and electric vehicles, respectively. The results show the energy efficiency of electric vehicles is less sensitive to the queuing effect at the intersection because of regenerative braking and the overall higher efficiency of the electric motor in contrast to the internal combustion engine, especially in stop-and-go scenarios. [ABSTRACT FROM AUTHOR]

Pulse bursts are generated in an Yb-doped all-normal dispersion (ANDi) passively mode-locked fiber laser with Raman scatting based on nonlinear polarization rotation (NPR). The number of pulses can be continuously adjusted from 1 to 8 by adjusting the pump power. The output power varies stepwise with linearly increasing of input power and pulse numbers in the bursts. We explain that the pulse bursts in ANDi fiber laser are formed by the clamping of pulse width and peak power. The energy evolution of the pulses burst with Raman component is experimentally realized in Yb-doped fiber laser, which is excepted to benefit energy controlling in applications such as laser material ablation and so on. [ABSTRACT FROM AUTHOR]

• Based on NPR, a passively mode-locked Yb-doped Raman fiber laser was demonstrated. • The unusual evolutions of spectra and pulses have been observed for the first time. • A flat broadband spectrum with 3-dB bandwidth of 48.50 nm was achieved. Based on nonlinear polarization rotation, a passively mode-locked Yb-doped intra-cavity cascaded Raman fiber laser was demonstrated, in which the unusual evolutions of spectra and pulses have been observed for the first time. The first-order stimulated Raman scattering (SRS) laser and the second-order cascaded SRS laser have been obtained successively under the different pump powers. Furthermore, due to the interaction of self-phase modulation, SRS, group velocity dispersion and other nonlinear effects, the spectra and pulses of the Raman fiber laser presented a unique anomalous evolution. With the increase in pump power, the decrease in the intensity of the first-order Stokes and the second-order Stokes waves and the narrowing of the pulses were observed for the first time. Finally, a flat broadband spectrum was achieved based on the unusual evolution of laser emission spectrum, which would be of great interest as a new method in generating the broadband continuum source. [ABSTRACT FROM AUTHOR]

Abstract: This paper deals with the effect of emulsifier content of sizing agent on the carbon fibre surface and interface properties of carbon fibre composites. The topographies of carbon fibres surface has been studied by the atomic force microscopy (AFM) and the failure surface of the composites has been studied by scanning electron microscopy (SEM). X-ray photoelectron spectroscopy (XPS) has been used to characterize the surface composition of the fibres. The effects of emulsifier content of sizing agent on the adhesion of surface on the interlaminar shear strength were examined. The results indicated that the emulsifier content of sizing agent has an important influence on the carbon fibres and carbon fibres composites. The 20wt% emulsifier content sizing agent (E-3) sized carbon fibres/epoxy resin composite showed better interfacial shear strengths. [Copyright &y& Elsevier]

Abstract: A carbon fiber/polyhedral oligomeric silsesquioxane/carbon nanotube (CF–POSS–CNT) hybrid reinforcement was prepared by grafting CNTs onto the carbon fiber surface using octaglycidyldimethylsilyl POSS as the linkage in an attempt to improve the interfacial properties between carbon fibers and an epoxy matrix. X-ray photoelectron spectroscopy, scanning electron microscopy, dynamic contact angle analysis and single fiber tensile testing were performed to characterize the hybrid reinforcements. Interlaminar shear strength (ILSS), impact toughness, dynamic mechanical analysis and force modulation atomic force microscopy were carried out to investigate the interfacial properties of the composites. Experimental results show that POSS and CNTs are grafted uniformly on the fiber surface and significantly increase the fiber surface roughness. The polar functional groups and surface energy of carbon fibers are obviously increased after the modification. Single fiber tensile testing results demonstrate that the functionalization does not lead to any discernable decrease in the fiber tensile strength. Mechanical property test results indicate the ILSS and impact toughness are enhanced. The storage modulus and service temperature increase by 11GPa and 17°C, respectively. POSS and CNTs effectively enhance the interfacial adhesion of the composites by improving resin wettability, increasing chemical bonding and mechanical interlocking. [Copyright &y& Elsevier]

Abstract: The carbon fiber/Si–O–C glass composite was prepared from the silicone and carbon fiber by pre-oxidation and spark plasma sintering (sintered composite). The mass loss of the sintered composite oxidized at 1200°C for 90min was 5%, which was lower than that of same dimension for similar composites, although the mass loss at 600°C was still high. This indicated its excellent oxidation resistance at elevated temperature. No cracks and pores were found in the sintered composite, indicating that the combination of pre-oxidation and spark plasma sintering was better than the pyrolysis for manufacturing dense composites. Compared with the flexural strength of about 60MPa for carbonaceous composites, the flexural strength of the sintered composite was obviously improved to 220MPa. Moreover, microstructures of the specimen before and after sintering as well as after oxidation were investigated. [Copyright &y& Elsevier]

• noise-like pulses generate in passively mode-locked Nd-doped all-fiber ring laser. • single-wavelength noise-like pulses with pulse duration of 1.79 ps were achieved. • 952.56 fs ultrashort noise-like pulses with a dual-wavelength were obtained. Single- and dual-wavelength noise-like pulses (NLP) with the uncompressed pulse duration about 1 ps were demonstrated for the first time in a Nd-doped all-fiber ring laser based on nonlinear polarization rotation (NPR). NLP with pulse width of 1.79 ps and pulse repetition rate of 14.29 MHz has been obtained under the maximum pump power of 297 mW as the laser operating at a single-wavelength of 1062.66 nm. In addition, 952.56 fs uncompressed NLP with pulse energy of 0.088 nJ was generated with the dual-wavelength of 1062.63 and 1064.78 nm. To our knowledge, our results proved for the first time that NPR mode-locking Nd-doped all-fiber ring laser can generate the NLP with the uncompressed pulse width about 1 ps, which would be of great interest as a seed source for all-fiber amplifiers for the generation of ultrashort large-energy pulses. [ABSTRACT FROM AUTHOR]