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The study proposes a Kalman Filter Family-schemed algorithm to identify the vehicle's parameters and evaluate the road roughness simultaneously, based on the response of an adapted monitoring vehicle. The vehicle is simplified as a three-dimensional multi-body system consisting of the unsprung mass of wheels and the sprung mass of the car body, connected by springs and dampers that represent the suspension system. Accelerometers and a gyroscope measure the accelerations or angular velocity of different positions of the vehicle during vibrations. The Kalman filter (KF) with unknown inputs enables the prediction of the car body's accelerations from those of wheels. On the other hand, the Augmented KF can compute the accelerations of wheels based on the car body's accelerations. Thus, an inner-systemic objective function incorporating the vehicle's parameter is built between the predicted and measured accelerations and solved in an optimized manner with the Genetic Algorithm, so that an individual complicated impact test or bump test is avoided. The numerical examples carry out field tests on a 900 m long standardized test road under two scenarios of with and without a bump. The road roughness estimated by these two KF methods from different measurements is used to calculate the International Roughness Index (IRI) and further the Riding Quality Index, which are compared with those directly provided by a standardized laser IRI profilometer. Accordance in between confirms the accuracy of the proposed algorithm under different scenarios. The analysis underlines the measurements from unsprung wheels that contact directly with the road enable a more accurate estimation of road roughness than those from the sprung car body. In addition, a vehicle speed lower than 40 km/h can provide a better estimation of the road profiles. [ABSTRACT FROM AUTHOR]

Femtosecond lasers (fs-lasers) offer a powerful and advantageous tool for fabricating a very large variety of materials. When processing transparent dielectrics, structural defects, such as cracks and broken edges, are always present, thus restricting the precision of fs-laser processing. In this paper, the formation and suppression mechanism of fs-laser induced structural defects are systematically studied. We demonstrate a novel method to improve the processing precision of lithium niobate (LiNbO 3) by elevating the substrate temperature. A crack-free ablation hole with a smooth edge was fabricated at the substrate temperature of 1000 ° C. Our results show that the increase of absorptivity and the suppression of incubation effects are responsible for the high precision processing at a high substrate temperature, which not only inhibits the formation of defects, but also additionally increases the efficiency of fs-laser processing. This work provides a simple method to efficiently suppress the defect formation induced by fs-laser in LiNbO 3 samples, paving the way for a new technique for high precision fs-laser processing. [ABSTRACT FROM AUTHOR]

Environmental protection PPP projects (EP-PPP) are subject to uncertainty during the project cycle, setting flexible project contract terms in their contracts can help establish and maintain an effective partnership. This article aims to reveal the contract flexibility mechanism of EP-PPP projects by studying the relationship between flexible contract term setting methods and their effects. Questionnaires, case studies and structural equation modeling (SEM) are applied to conduct quantitative analysis. The research shows that although some flexible terms have been adopted in current EP-PPP contracts, there is still much room for improvement. In order to deal with unforeseen risks and challenges, it is necessary to consider: (1) List uncertainties as much as possible and set up response methods accordingly; (2) Guarantee a certain degree of flexibility in uncertainty response methods; (3) Give the project itself a certain degree of autonomous response power; (4) Leave plenty space for changes that may be needed in the future. The study results can help project practitioners enhance their understanding of flexible contract terms and help to promote contract flexibility in EP-PPP projects in a context-specific manner, thereby facilitating project success. [ABSTRACT FROM AUTHOR]

In the process of ocean exploration, highly accurate and sensitive measurements of seawater temperature and pressure significantly impact the study of seawater's physical, chemical, and biological processes. In this paper, three different package structures, V-shape, square-shape, and semicircle-shape, are designed and fabricated, and an optical microfiber coupler combined Sagnac loop (OMCSL) is encapsulated in these structures with polydimethylsiloxane (PDMS). Then, the temperature and pressure response characteristics of the OMCSL, under different package structures, are analyzed by simulation and experiment. The experimental results show that structural change hardly affects temperature sensitivity, and square-shape has the highest pressure sensitivity. In addition, with an input error of 1% F.S., temperature and pressure errors were calculated, which shows that a semicircle-shape structure can increase the angle between lines in the sensitivity matrix method (SMM), and reduce the effect of the input error, thus optimizing the ill-conditioned matrix. Finally, this paper shows that using the machine learning method (MLM) effectively improves demodulation accuracy. In conclusion, this paper proposes to optimize the ill-conditioned matrix problem in SMM demodulation by improving sensitivity with structural optimization, which essentially explains the cause of the large errors for multiparameter cross-sensitivity. In addition, this paper proposes to use the MLM to solve the problem of large errors in the SMM, which provides a new method to solve the problem of the ill-conditioned matrix in SMM demodulation. These have practical implications for engineering an all-optical sensor that can be used for detection in the ocean environment. [ABSTRACT FROM AUTHOR]

Stress/force monitoring of prestressing tendons is challenging but crucial to the evaluation of the safety of structures in which they are used. To this end, a smart elasto-magneto-electric (EME) sensor based on elasto-magnetic (EM) and magneto-electric (ME) effects is proposed for noncontact field monitoring of the absolute stress in these steel tendons. In this paper, our research in design, implementation, and application of the EME sensory system for non-destructive monitoring of prestressing tendons is overviewed. The results confirm that the developed EME sensor possesses high repeatability, ease of operation and maintenance, corrosion resistance, and long expected service-life. It is demonstrated that the proposed EME sensory technology is feasible for the stress/force monitoring of prestressing tendons in both new and existing structures and the EME sensory system is reliable and stable. [ABSTRACT FROM AUTHOR]

Significant developments have been made in the navigation of autonomous mobile robots within indoor environments; however, there still remain challenges in the face of poor map construction accuracy and suboptimal path planning, which limit the practical applications of such robots. To solve these challenges, an enhanced Rao Blackwell Particle Filter (RBPF-SLAM) algorithm, called Lidar-based RBPF-SLAM (LRBPF-SLAM), is proposed. In LRBPF, the adjacent bit poses difference data from the 2D Lidar sensor which is used to replace the odometer data in the proposed distribution function, overcoming the vulnerability of the proposed distribution function to environmental disturbances, and thus enabling more accurate pose estimation of the robot. Additionally, a probabilistic guided search-based path planning algorithm, gravitation bidirectional rapidly exploring random tree (GBI-RRT), is also proposed, which incorporates a target bias sampling to efficiently guide nodes toward the goal and reduce ineffective searches. Finally, to further improve the efficiency of navigation, a path reorganization strategy aiming at eliminating low-quality nodes and improving the path curvature of the path is proposed. To validate the effectiveness of the proposed method, the improved algorithm is integrated into a mobile robot based on a ROS system and evaluated in simulations and field experiments. The results show that LRBPF-SLAM and GBI-RRT perform superior to the existing algorithms in various indoor environments. [ABSTRACT FROM AUTHOR]

The two-stage suspension system (TSSS) is designed for the fiber optic vector hydrophone (FOVH) to isolate the vibration from the mooring rope. The acceleration transmissibility of the TSSS is studied theoretically and experimentally. The results show that the TSSS has a major advantage over the traditional one-stage suspension system (OSSS). Typically, the vibration isolation of the TSSS is demonstrated to be over 25 dB higher than that of the OSSS at 100 Hz. Meanwhile, it is demonstrated that the TSSS has little negative influence on the in-band acceleration response of the FOVH. The TSSS has the prospect of reducing the mechanical noise of the FOVH, which is conducive to suppressing the self-noise and enhancing the ability of weak signal detection. [ABSTRACT FROM AUTHOR]

A theoretical and experimental study on the stimulated Brillouin scattering (SBS) threshold for optical pulse in the presence of modulation instability (MI) in long optical fiber is presented. The effects of MI on the SBS gain and threshold are analyzed based on the coupled-wave equation. An analytic expression is obtained to calculate the SBS threshold in the presence of MI. Numerical simulation is conducted to study the effects of the repetition rate and amplified spontaneous emission (ASE) noise on the SBS threshold for optical pulses. An experiment is conducted, and the results agree well with the theoretical analysis. The results clearly reveal how MI affects the Brillouin gain and SBS threshold of optical pulses in long optical fiber. The SBS threshold is affected by the ASE noise level and the repetition rate of the optical pulse. The study is helpful for the power evaluation of interferometric fiber sensing systems and optical power transmission systems. [ABSTRACT FROM AUTHOR]

Modulation instability (MI) is the main limitation factor of the maximum optical power in long-haul phase-sensitive optical time domain reflectometry (Φ-OTDR), and induces signal fading and serious phase noise. In this paper, a method of coherent seed injection is proposed to suppress the MI-induced phase noise in long-haul Φ-OTDR. The spontaneous MI is suppressed by stimulating induced MI in an optical fiber. The visibility of the signal in Φ-OTDR is enhanced and the phase noise is suppressed significantly. This paper offers an effective method to increase the maximum input power with the MI-induced phase noise suppressed in the long-haul Φ-OTDR system. As a result, the maximum input power and sensing distance can be potentially increased, which is greatly beneficial to the enhancement of the performance of long-haul Φ-OTDR. [ABSTRACT FROM AUTHOR]

The phase-generated-carrier (PGC) method is one of the popular interrogation methods for the interferometric fiber-optic sensor systems. Among varieties of specifications, the noise characteristic is a key one that determines the minimum detectable signal. However, the mechanism of the noise transfer process in the PGC-based interferometric fiber-optic sensor has not been reported to the best knowledge. In this paper, the influences of three different types of noise sources on the noise floor of the PGC-based interferometric fiber-optic sensor system are studied systematically. On the basis of that, the phase noise transfer model is built and verified experimentally. The results depict that the theoretical model can well predict the experimental result. With the proposed theoretical model, the prediction and analysis of the output phase noise in the PGC-based interferometric fiber-optic sensor is available. In addition, the proposed model provides a potential support for locking the initial phases to suppress the common-mode noise in the PGC-based system. In this sense, the proposed model is a significant tool for the noise-target design and construction of the PGC-based in terferometric fiber-optic sensor system. [ABSTRACT FROM AUTHOR]

The evaluation of road roughness plays a critical role in the life-long maintenance of the highway system. This study proposes a Kalman Filter-based scheme to evaluate the road roughness indirectly from the response of a moving adapted monitoring vehicle. Key feature of the scheme is the use of measurements from dynamic tire pressure of unsprung mass components that directly interact with roads. Combination of ideal gas law and elastic contact model results in a nonlinear relationship between the tire pressure and the contact force, in which the parameters are calibrated by the Extended Kalman Filter. Identification of vehicle's physical parameters adopts the power spectrum method with a known-size bump test. Subsequently, the road roughness is treated as unknowns in the vehicle's state-space equation and solved by the Discrete Kalman Filter with unknown inputs. The estimated road roughness profiles are then used to calculate the International Roughness Index and compared with that provided by the standardized laser profilometer, an outer-systematic comparison. On the other hand, available measurements are split into groups that measurements of tire pressure are used to predict the accelerations of the car body and wheels and compared with these accelerations directly measured from accelerometers, an inner-systemic comparison. Field tests are carried out on a 900 m long standardized road under two scenarios of with and without the bump and four different vehicle running speeds from 20 to 50 km/h. Consistence of comparison from different perspectives proves the reliability of the proposed scheme. In addition, the results unveil that the scenario with a lower running speed can offer a better estimation of road roughness. [ABSTRACT FROM AUTHOR]

To adapt to the complex application of polyurethane bearings, it is feasible to improve the tribological performance of single polyurethane-based friction materials through the synergistic effect produced by multi-component-lubricating fillers. In this context, rather than using tungsten disulfide (WS2), which has demonstrated excellent self-lubricating performance as a lubricating oil additive, this paper proposes that WS2 and single-walled carbon nanotubes (SWNTs) can be designed for addition into a polyether 4,4′-diphenylmethane diisocyanate (MDI) polyurethane matrix as self-lubricating fillers so as to explore the synergistic effect of micro- and nano-lubricating fillers on the tribological performance of polyurethane matrix materials. Through a series of characterizations and tests, it was found that the dispersion of two-component-lubricating additives in a polyurethane matrix is improved when the ratio of WS2 to SWNTs is roughly 2:1. In this case, the tribological performance of polyurethane matrix composites is more satisfactory than at other ratios. In addition, compared with the blank sample, the tribological performance of the synergistically modified polyurethane composites under dry friction is more significantly improved with the increase in contact load, while there is no significant improvement under water lubrication. Aside from contributing to the idea of exploring the synergistic effect of WS2 and other micro or nanofillers, this method also opens up the possibility of practically applying WS2 in the field of friction. [ABSTRACT FROM AUTHOR]

Background: With a pronounced and historically unprecedented tendency of population ageing, research on ageing and related disorders has been increasingly brought into focus. Horticultural therapy (HT), as an important role of social prescribing, has been an integrative for decades. This systematic review and meta-analysis aimed to evaluate HT for general health in older adults. Methods: Electronic databases including PubMed, Web of Science, ScienceDirect, the Cochrane Library, MEDLINE (Ovid), EMBASE (Ovid), CINAHL (EBSCO), China National Knowledge Infrastructure (CNKI), and the Wanfang database, grey literature databases and clinical trials registers were searched from inception to March 2021. Randomized controlled trials (RCTs), quasi-RCTs (QRCTs) and the cohort studies about HT for adults aged over 60 were included in this study. Outcome measures were physical function, quality of life, BMI, mood tested by self-reported questionnaire and the expression of the immune cells. The study was registered under PROSPERO (CRD42019146184). Results: Totally, fifteen studies (thirteen RCTs and two cohort studies) involving 1046 older participants were included. Meta-analysis showed that HT resulted in better quality of life (MD 2.09, 95% CI [1.33, 2.85], P<0. 01) and physical function (SMD 0.82, 95% [0.36, 1.29], P<0.01) compared with no-gardener; the similar findings showed in BMI (SMD -0.30, 95% [-0.57, -0.04], P = 0.02) and mood tested by self-reported questionnaire (SMD 2.80, 95% CI [1.82, 3.79], P<0. 01). And HT might be conducive on blood pressure and immunity, while all the evidence were moderate-quality judged by GRADE. Conclusions: HT may improve physical function and quality of life in older adults, reduce BMI and enhance positive mood. A suitable duration of HT may be between 60 to 120 minutes per week lasting 1.5 to 12 months. However, it remains unclear as to what constitutes an optimal recommendation. [ABSTRACT FROM AUTHOR]

Aim: The present study aimed to elucidate the potential function of microRNA 1228 (miR-1228) on the high glucose (HG)-damaged human renal proximal tubule cells (HK-2) and the underlying mechanism. Methods: The datasets GSE47185 and GSE51674 were downloaded from the Gene Expression Omnibus database for mining differently expressed mRNAs and miRNAs, respectively. Bioinformatics online tools were applied to predict the binding sites between miR-1228 and thrombospondin 2 (THBS2), which was confirmed by dual-luciferase assay. Real-time quantitative polymerase chain reaction was used to detect the mRNA level of miR-1228/THBS2. Western blot was used to detect the protein level of THBS2 and the PI3K/AKT signaling pathway-associated markers. HK-2 cells were cultured in HG (30 mM) to mimic hyperglycemia. Cell counting kit 8 and flow cytometry assays were utilized to determine the cell proliferation and apoptosis. Results: The expression of THBS2 was significantly upregulated in diabetic nephropathy (DN) based on bioinformatics tools and identified as a direct target of miR-1228. miR-1228 was downregulated in DN and HG-damaged HK-2 cells. HG notably reduced HK-2 cell proliferation. This negative effect was attenuated by transfecting with an miR-1228 mimic and aggravated by transfecting with an miR-1228 inhibitor. However, under basal condition, there was no significant effect on the HK-2 cell proliferation among blank control, mimic, and inhibitor groups. Overexpression of THBS2 abolished the elevating effect of the miR-1228 mimic on the HG-damaged HK-2 cell proliferation, while restored the inhibitory effects of the miR-1228 mimic on the cell apoptosis. On the contrary, the suppressive effects on the proliferation and the enhancive effects on the apoptosis by silencing miR-1228 in HK-2 cells stimulated with HG can be weakened by recommendation of THBS2 small interference RNAs. Furthermore, we also found that HG significantly enhanced the phosphorylation levels of PI3K and AKT. In terms of overexpression and knockdown experiments, Western blot analysis further revealed that miR-1228 inhibited the activation of the PI3K/AKT signaling pathway in HG-damaged HK-2 cells by regulating THBS2. Conclusion: The findings illustrated that miR-1228 improved survivability and inhibited apoptosis in HK-2 cells stimulated with HG partly by restraining the activation of the PI3K/AKT signaling pathway. [ABSTRACT FROM AUTHOR]

A low-distortion 3×3 interrogation algorithm requires the accurate parameters calibration of the 3×3 coupler-based Michelson interferometer. The ellipse fitting method with a frequency modulation conducted on the laser is one way that contributes to the implementation of the calibration. However, the unused dangling tail fiber of the 3×3 coupler-based Michelson interferometer generates a harmful echo and leads to an unexpected triple-beam interference. Consequently, it gives rise to a drastic fluctuation on the desired elliptical Lissajous figure, which damages the accuracy and stability of the calibration greatly. In this paper, the echo influence on the calibration is studied theoretically and experimentally. A theoretical model is built based on the coupled mode theory and the interference theory, which is verified by the experiment. According to the model, the echo coefficient, the input state of polarization and the length of the unused dangling tail fiber are three factors that affect the intensity of the fluctuation. Two practical methods of angle cleaving and pulse delay are adopted to suppress the echo influence and restore the accuracy of the calibration in the paper, which are both demonstrated to be feasible and stable. In the end, the suitable applications of the two methods are discussed, which are different for them due to their characteristics. This research has laid the foundation for the practical application of the frequency-modulation-based calibration to the 3×3 coupler-based Michelson interferometric probe. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to focus on the preparation of Kevlar fiber (KF) and alkaline hydrolyzed KF (KF-H) to improve the dispersed condition of polyaniline (PAn), as the aggregation of PAn would lead to some adsorption sites buried. And then the materials were used to enrich anionic dye Congo red (CR) from aqueous solution. Design/methodology/approach: The materials (KF@PAn and KF-H@PAn) were designed by means of "diffusion-interfacial-polymerization" under mild condition as high affinity due to the structural properties of PAn, KF and KF-H. The dispersed degree of PAn on the surface of KF and KF-H was validated according to adsorption efficiency for CR. Findings: The content of PAn introduced was not beyond 20 wt.%, while adsorption capacity for CR was significantly enhanced by 4–8 times (on the basis of kinetic data) according to the calculation only by the content of PAn due to KF and alkaline hydrolyzed KF exhibited almost no adsorption for CR, indicating dispersed situation of PAn coating was greatly enhanced and more active sites exposed, which was favorable for the adsorption process. Presence of NaCl would exhibit a more or less positive effect on CR uptake, suggesting the materials could be used for high salt environment. Research limitations/implications: The investigated means of dispersed degree of PAn on the surface of KF and KF-H are the further and future investigation. Practical implications: This study will provide a method to improve the dispersed situation of PAn and a theoretical support to treat anionic dyes from aqueous solution especially for salt environment. Originality/value: The results showed that the dispersed condition of PAn on the surface of KF and KF-H was greatly improved. According to the adsorption capacities for CR, it can be concluded that part of adsorption sites were buried due to the aggregation of PAn, and introduction of KF and KF-H, buried adsorption sites decreased greatly. This study will provide a method to decrease buried adsorption sites of PAn and a contribution for their convenient application in wastewater treatment especially for high salt environment. [ABSTRACT FROM AUTHOR]

This study develops and tests an automatic pixel-level image recognition model to reduce the amount of manual labor required to collect data for road maintenance. Firstly, images of six kinds of pavement distresses, namely, transverse cracks, longitudinal cracks, alligator cracks, block cracks, potholes, and patches, are collected from four asphalt highways in three provinces in China to build a labeled pixel-level dataset containing 10,097 images. Secondly, the U-net model, one of the most advanced deep neural networks for image segmentation, is combined with the ResNet neural network as the basic classification network to recognize distressed areas in the images. Data augmentation, batch normalization, momentum, transfer learning, and discriminative learning rates are used to train the model. Thirdly, the trained models are validated on the test dataset, and the results of experiments show the following: if the types of pavement distresses are not distinguished, the pixel accuracy (PA) values of the recognition models using ResNet-34 and ResNet-50 as basic classification networks are 97.336% and 95.772%, respectively, on the validation set. When the types of distresses are distinguished, the PA values of models using the two classification networks are 66.103% and 44.953%, respectively. For the model using ResNet-34, the category pixel accuracy (CPA) and intersection over union (IoU) of the identification of areas with no distress are 99.276% and 99.059%, respectively. For areas featuring distresses in the images, the CPA and IoU of the model are the highest for the identification of patches, at 82.774% and 73.778%, and are the lowest for alligator cracks, at 14.077% and 12.581%, respectively. [ABSTRACT FROM AUTHOR]

Fiber-optic hydrophone (FOH) is a significant type of acoustic sensor, which can be used in both military and civilian fields such as underwater target detection, oil and natural gas prospecting, and earthquake inspection. The recent progress of FOH is introduced from five aspects, including large-scale FOH array, very-low-frequency detection, fiber-optic vector hydrophone (FOVH), towed linear array, and deep-sea and long-haul transmission. The above five aspects indicate the future development trends in the FOH research field, and they also provide a guideline for the practical applications of FOH as well as its array. [ABSTRACT FROM AUTHOR]

Crowd flows prediction is an important problem of urban computing whose goal is to predict the number of incoming and outgoing people of regions in the future. In practice, emergency applications often require less training time. However, there is a little work on how to obtain good prediction performance with less training time. In this paper, we propose a simplified deep residual network for our problem. By using the simplified deep residual network, we can obtain not only less training time but also competitive prediction performance compared with the existing similar method. Moreover, we adopt the spatio-temporal attention mechanism to further improve the simplified deep residual network with reasonable additional time cost. Based on the real datasets, we construct a series of experiments compared with the existing methods. The experimental results confirm the efficiency of our proposed methods. [ABSTRACT FROM AUTHOR]

Accumulation of extracellular amyloid-β (Aβ) in hippocampal subregions is a hallmark of Alzheimer's disease (AD), which promotes neuronal apoptosis, potentiates cognitive decline and play a causative role in AD pathogenesis. However, whether this process is controlled by distinct miRNAs at the posttranscriptional level remain fascinating but poorly understood. Using post mortem hippocampal samples from human AD patients and 3xTg-AD mouse, we demonstrate that miR-342-3p expression was significantly induced during the AD development. With the aid of intrahippocampal injection of miR-342-3p antagomir, we further show that in vivo miR-342-3p inhibition synergistically improved cognitive deficits in 3xTg-AD mice. The hippocampal Aβ-plaque burden in 3xTg-AD mice, as revealed by immunohistochemical analysis with 4G8 antibody, was attenuated also. Mechanistically, the upregulation of neuronal miR-342-3p is linked to an increase in the activation of the stress kinase c-Jun N-terminal kinase with the subsequent death of the neurons in Aβ-challenged HT22 hippocampal neuronal cells. These findings support the model that derangement of hippocampus signal transduction and subsequent neuronal apoptosis in AD arises as a consequence of increased Aβ burden and chronic activation of the JNK MAPK cascade in a miR-342-3p-dependent manner. Overall, we described for the first time the regulatory activity of miR-342-3p on relevant Aβ metabolism pathways in Alzheimer's disease. [ABSTRACT FROM AUTHOR]

Two diglycolamide homologs, N,N,N′,N′-tetraoctyl-3,6-dioxaoctane diamide (DOODA) and N,N,N′,N′-tetraoctyl-3,6,9-trioxaundecane diamide (TOUDA), were synthesized. Their extraction behaviors of Am and Eu were investigated and compared with those of N,N,N′,N′-tetraoctyl-3-oxapentane diamide (TODGA). The extraction ability toward Am and Eu decreased with increasing etheric oxygen number in the extractant structure. In contrast to TODGA, an very interesting inversion on the selectivity occurred for DOODA and TOUDA, which were more favor of extracting Am than Eu. The maximum SF of 3.5 for DOODA can be achieved at 3.0 mol/L HNO. The stoichiometries of extracted species and extraction thermodynamic parameters were also presented. Graphical Abstract: [ABSTRACT FROM AUTHOR]

To clarify the structure-property relationships of pyridylpyrazole ligands and provide guidance for the design of new and more efficient ligands for the selective extraction of actinides over lanthanides, a series of alkyl-substituted pyridylpyrazole ligands with different branched chains at different positions of the pyrazole ring were synthesized. Extraction experiments showed that the pyridylpyrazole ligands exhibited good selective extraction abilities for AmIII ions, and the steric effects of the branched chain had a significant impact on the distribution ratios of AmIII and EuIII ions as well as the separation factor. Moreover, both slope analyses and UV/Vis spectrometry titrations indicated the formation of a 1:1 complex of 2-(1-octyl-1 H-pyrazol-3-yl)pyridine (C8-PypzH) with EuIII ions. The stability constant (log K) for this complex obtained from the UV/Vis titration was 4.45 ± 0.04. Single crystals of the complexes of 3-(2-pyridyl)pyrazole (PypzH) with Eu(NO3)3 and Sm(NO3)3 were obtained; PypzH acts as a bidentate ligand in the crystal structures, and the N atom with a bound H atom did not participate in the coordination. In general, this study revealed some interesting findings on the effects of the alkyl-chain structure and the special complexation between pyridylpyrazole ligands and LnIII ions. [ABSTRACT FROM AUTHOR]

In this work, we have successfully fabricated unique three-dimensional (3D) dendritic NiS nanosheet arrays on nickel foam (NiS-Ni) through a simple solution method, oxidizing fresh nickel foam under a heat treatment and following a sulfidation process without the need for any additional nickel sources, surfactant, or templates. The morphology of the NiS-Ni was observed by SEM and TEM, while the crystallinity was revealed by XRD pattern. When tested as the electrode for supercapacitors, the NiS dendritic arrays grown on nickel foam display excellent performance, demonstrating the specific capacity of 465.9 F g at the current density of 1 A g. After 7000 cycles, the NiS-Ni electrode can maintain 101.79 % of its highest value, which demonstrates its superior cycle stability performance. Also, the NiS-Ni electrode exhibits high capacity retention when fast charging. These results establish that the NiS-Ni binder-free electrode exhibits greatly improved electrochemical performance with high capacitance and excellent cycling stability. [ABSTRACT FROM AUTHOR]

Background: Musculoskeletal disorders (MSD) comprise a wide range of conditions, associated with an enormous pain and impaired mobility, and are affecting people's lives and work. Management of musculoskeletal disorders typically involves a multidisciplinary team approach. Positive findings have been found in previous studies evaluating the effectiveness of complementary therapies, though little attention has been paid to evaluating of the effectiveness of integrated packages of care combining conventional and complementary approaches for musculoskeletal conditions in a National Health Service (NHS) setting. Objective: To determine the feasibility of all aspects of a pragmatic observational study designed: (1) to evaluate the effectiveness and cost effectiveness of integrated treatments for MSDs in an integrated NHS hospital in the UK; (2) to determine the acceptability of the study design and research process to patients; (3) to explore patients' expectation and experience of receiving integrated treatments. Methods: This is an observational feasibility study, with 1-year recruitment and 1-year follow-up, conducted in Royal London Hospital for Integrated Medicine, University College London Hospital Trust, UK. All eligible patients with MSDs newly referred to the hospital were included in the study. Interventions are integrated packages of care (conventional and complementary) as currently provided in the hospital. SF-36™ Health Survey, short form Brief Pain Inventory, Visual Analogue Scale, and modified Client Service Receipt Inventory will be assessed at 4/5 time points. Semi-structured interview/focus group will be carried out before treatment, and 1 year after commence of treatment. Discussion: We intend to conduct a pragmatic observational study of integrated medical treatment of MSDs at a public sector hospital. It will inform the design of a future trial including recruitment, retention, suitability of the outcome measures and patients experiences. [ABSTRACT FROM AUTHOR]

We demonstrate the modulation instability (MI) and four-wave mixing (FWM) spectra at the input of a pump accompanied with a seed in the dispersion-shifted fiber. By numerically solving the nonlinear Schrodinger equation, it is confirmed that there are two regions as the absolute value of the second-order fiber dispersion decreases, where MI and FWM dominates, respectively. We attribute this phenomenon to the competition between MI and FWM. Furthermore, for the FWM-dominating region, it can be divided into two subregions according to the different power levels of MI, which mainly results from the power transfer between MI and dispersive wave. Our results may lead to a further understanding of nonlinear interactions in optical fiber. [ABSTRACT FROM AUTHOR]

The mammalian olfactory system uses a large family of odorant receptors (ORs) to detect and discriminate amongst a myriad of volatile odor molecules. Understanding odor coding requires comprehensive mapping between ORs and corresponding odors. We developed a means of high-throughput in vivo identification of OR repertoires responding to odorants using phosphorylated ribosome immunoprecipitation of mRNA from olfactory epithelium of odor-stimulated mice followed by RNA-Seq. This approach screened the endogenously expressed ORs against an odor in one set of experiments using awake and freely behaving mice. In combination with validations in a heterologous system, we identified sets of ORs for two odorants, acetophenone and 2,5-dihydro-2,4,5-trimethylthiazoline (TMT), encompassing 69 OR-odorant pairs. We also identified shared amino acid residues specific to the acetophenone or TMT receptors and developed models to predict receptor activation by acetophenone. Our results provide a method for understanding the combinatorial coding of odors in vivo. [ABSTRACT FROM AUTHOR]

Botulinum neurotoxin type A1 (BoNT/A1) is a potent protein toxin responsible for the potentially fatal human illness botulism. Notwithstanding, the long-lasting flaccid muscle paralysis caused by BoNT/A has led to its utility as a powerful and versatile bio-pharmaceutical. The flaccid paralysis is due to specific cleavage of neuronal SNAREs by BoNTs. However, actions of BoNTs on intoxicated neurons besides the cleavage of SNAREs have not been studied in detail. In this study we investigated by microarray analysis the effects of BoNT/A and a catalytically inactive derivative (BoNT/A ad) on the transcriptome of human induced pluripotent stem cell (hiPSC)-derived neurons at 2 days and 2 weeks after exposure. While there were only minor changes in expression levels at 2 days post exposure, at 2 weeks post exposure 492 genes were differentially expressed more than 2-fold in BoNT/A1-exposed cells when compared to non-exposed populations, and 682 genes were differentially expressed in BoNT/A ad-exposed cells. The vast majority of genes were similarly regulated in BoNT/A1 and BoNT/A ad-exposed neurons, and the few genes differentially regulated between BoNT/A1 and BoNT/A ad-exposed neurons were differentially expressed less than 3.5 fold. These data indicate a similar response of neurons to BoNT/A1 and BoNT/A ad exposure. The most highly regulated genes in cells exposed to either BoNT/A1 or BoNT/A ad are involved in neurite outgrowth and calcium channel sensitization. [ABSTRACT FROM AUTHOR]

The effect of die temperature on the mechanical performance and morphology of polyethylene (PE) pipe prepared via mandrel rotation extrusion is described. The experimental results showed that during the rotation extrusion of PE pipe, the hoop flow caused by the mandrel rotation was superimposed on the axial flow to deviate the formed shish-kebab from the axial direction which was favorable to improve the hoop strength of the PE pipe. However, high die temperature caused relaxation of most of the oriented molecular chains and the consequent formation of isotropic crystals in the PE pipe, whereas too low a die temperature led to imperfections in the PE pipe. As a result, there was an optimum temperature range for the enhancement of the hoop strength. When the mandrel rotated at 6 r/min, the hoop strength of the PE pipes prepared at the die temperature of 170°C reached the maximum value, 31.8 MPa, 22% and 29% higher than that at 150°C and 210°C, respectively. [ABSTRACT FROM AUTHOR]

The intensity distribution of a laser beam (laser beam profile) is one of its most important characteristics because it yields information on the non-uniformity, centroid, centroid jitter and beam quality. A novel measurement method for obtaining a large laser beam intensity distribution based on CCD diffuse transmission imaging is proposed. The measurement principle is presented. The measurement components of the system have been designed. The layout of the system and the design of a diffuse transmission sampling target are emphasized. The methods of correcting geometric and intensity distortion of the spot are described in detail. The method to calibrate the power coefficient is also given. After the laser spot correction, we can obtain the precise laser beam intensity profile as well as the laser power. The presented test results validate the method. In the measurement field of large laser beams, the method can measure the profile with a non-uniformity of less than 1%, and laser power within 2% error compared with the calibration power meter. The measurement system can be used as a standard measurement instrument after being calibrated when manufactured. [ABSTRACT FROM AUTHOR]

Electronic maps play an important role in the field of urban traffic management, but the interface functions provided by map service agencies are limited, and commercial maps are generally expensive. Furthermore, the map generation algorithms based on the Global Positioning System (GPS) data can be very complex and take up a lot of storage space, which limits their application to specific practical problems, such as the real-time update of area maps, temporary road control, emergency route planning, and other scenarios. In order to solve this problem, an intuitive, extensible, and flexible method of constructing urban road maps is proposed. Using the Othello-coordinated method, the representation of the unit grid cell was redesigned. Through this method, the disadvantages of the raster map's large storage space and computing resource requirements are compensated for during processing, improving the topological expression ability of the raster map and the speed with which the construction of the map is realized. The application potential of the proposed method is demonstrated by the evaluation of public transport service and road network resilience. In our experiments, the optimization efficiency of storage space was up to 99.914%, and the calculation accuracy of bus coverage was about 99.86%. [ABSTRACT FROM AUTHOR]

Film-forming resins, as carriers of antifouling coatings, play an essential role in the functional performance of coatings. With the gradual promotion of coatings in the field of marine antifouling, the preparation of film-forming resins containing hydrophilic chain segments is urgently needed to give full play to the functional and time-sensitive performance of antifouling coatings. In this paper, the single-ended isocyanate group (NCO) polyurethane (PU) prepolymer with hydrophilic chain segments was prepared and grafted onto an epoxy resin (EP) molecular chain to obtain the PU/EP grafted blend. Successful preparation of the PU/EP grafted blends was confirmed by infrared spectrum analysis. Simultaneously, the grafted blend was cured, and its hydrophilicity and mechanical properties were also tested. The results demonstrate that the grafted method can effectively improve the hydrophilicity of the film-forming resin while maintaining its mechanical properties. It can be concluded from the hydrophilic and mechanical properties of the materials that the comprehensive properties of PU/EP grafted blends are the best when the PU content is between 40% and 50%. The hanging plate test showed that the antifouling effect of the antifouling coating prepared by hydrophilic modified PU/EP film-forming resin was better than that of the traditional antifouling coating under the experimental conditions. [ABSTRACT FROM AUTHOR]

In order to meet the needs of phase generated carrier (PGC) demodulation technology for interferometric fiber optic hydrophones, we proposed an optical microfiber all-optical phase modulator (OMAOPM) based on the photo-induced thermal phase shift effect, which can be used as a phase carrier generation component, so as to make the modulation efficiency and working bandwidth of this type of modulator satisfy the requirements of underwater acoustic signal demodulation applications. We analyzed the modulation principle of this modulator and optimized the structural parameters of the optical microfiber (OM) when the waist length and waist diameter of OM are 15 mm and 1.4 μm, respectively. The modulation amplitude of the modulator can reach 1 rad, which can meet the requirements of sensing applications. On this basis, the fiber optical hydrophone PGC-Atan demodulation system was constructed, and the simulated underwater acoustic signal test demodulation research was carried out. Experimental results showed that the system can demodulate underwater acoustic signals below 1 kHz. [ABSTRACT FROM AUTHOR]

Road roughness is an important factor in road network maintenance and ride quality. This paper proposes a road-roughness estimation method using the frequency response function (FRF) of a vehicle. First, based on the motion equation of the vehicle and the time shift property of the Fourier transform, the vehicle FRF with respect to the displacements of vehicle–road contact points, which describes the relationship between the measured response and road roughness, is deduced and simplified. The key to road roughness estimation is the vehicle FRF, which can be estimated directly using the measured response and the designed shape of the road based on the least-squares method. To eliminate the singular data in the estimated FRF, the shape function method was employed to improve the local curve of the FRF. Moreover, the road roughness can be estimated online by combining the estimated roughness in the overlapping time periods. Finally, a half-car model was used to numerically validate the proposed methods of road roughness estimation. Driving tests of a vehicle passing over a known-sized hump were designed to estimate the vehicle FRF, and the simulated vehicle accelerations were taken as the measured responses considering a 5% Gaussian white noise. Based on the directly estimated vehicle FRF and updated FRF, the road roughness estimation, which considers the influence of the sensors and quantity of measured data at different vehicle speeds, is discussed and compared. The results show that road roughness can be estimated using the proposed method with acceptable accuracy and robustness. [ABSTRACT FROM AUTHOR]