Role of durotomy on function outcome, tissue sparing, inflammation, and tissue stiffness after spinal cord injury in rats.

Currently, there is a lack of effective treatments for spinal cord injury (SCI), a debilitating medical condition associated with enduring paralysis and irreversible neuronal damage. Extradural decompression of osseous as well as soft tissue components has historically been the principal objective of surgical procedures. Nevertheless, this particular surgical procedure fails to tackle the intradural compressive alterations that contribute to secondary SCI. Here, we propose an early intrathecal decompression strategy and evaluate its role on function outcome, tissue sparing, inflammation, and tissue stiffness after SCI. Durotomy surgery significantly promoted recovery of hindlimb locomotor function in an open-field test. Radiological analysis suggested that lesion size and tissue edema were significantly reduced in animals that received durotomy. Relative to the group with laminectomy alone, the animals treated with a durotomy had decreased cavitation, scar formation, and inflammatory responses at 4 weeks after SCI. An examination of the mechanical properties revealed that durotomy facilitated an expeditious restoration of the injured tissue's elastic rigidity. In general, early decompressive durotomy could serve as a significant strategy to mitigate the impairments caused by secondary injury and establish a more conducive microenvironment for prospective cellular or biomaterial transplantation.

A new in situ magnetic method to indicate the source and seasonal diffusion of heavy metal contamination at Qingdao Beach, China.

The accumulation of heavy metals from sewage and garbage dumping can seriously impact beach tourism and thus the local economy, but it is difficult to quickly and accurately determine the pollution location and source of heavy metals and clarify their diffusion range. This study investigates a new in situ magnetic testing method to address this issue. (1) The in situ method can be used to effectively and quickly evaluate heavy metal sources and diffusion ranges based on the distribution of κ values. (2) According to chemical experiments, the specific elements polluting a beach can be determined, such as the Cr, Ni, Zn, and Fe pollution of Beach No. 3. (3) Although κ values for assessing heavy metal pollution on different beaches vary, metal pollution occurs when the higher κ value is more than 50 times the lower κ value on the same beach. (4) The κ values vary in different seasons due to the influence of natural factors and urban seasonal sewage policies.

Classification of cognitive ability of healthy older individuals using resting-state functional connectivity magnetic resonance imaging and an extreme learning machine.

BACKGROUND: Quantitative determination of the correlation between cognitive ability and functional biomarkers in the older brain is essential. To identify biomarkers associated with cognitive performance in the older, this study combined an index model specific for resting-state functional connectivity (FC) with a supervised machine learning method. METHODS: Performance scores on conventional cognitive test scores and resting-state functional MRI data were obtained for 98 healthy older individuals and 90 healthy youth from two public databases. Based on the test scores, the older cohort was categorized into two groups: excellent and poor. A resting-state FC scores model (rs-FCSM) was constructed for each older individual to determine the relative differences in FC among brain regions compared with that in the youth cohort. Brain areas sensitive to test scores could then be identified using this model. To suggest the effectiveness of constructed model, the scores of these brain areas were used as feature matrix inputs for training an extreme learning machine. classification accuracy (CA) was then tested in separate groups and validated by N-fold cross-validation. RESULTS: This learning study could effectively classify the cognitive status of healthy older individuals according to the model scores of frontal lobe, temporal lobe, and parietal lobe with a mean accuracy of 86.67%, which is higher than that achieved using conventional correlation analysis. CONCLUSION: This classification study of the rs-FCSM may facilitate early detection of age-related cognitive decline as well as help reveal the underlying pathological mechanisms.

Icariin alleviates diabetic renal interstitial fibrosis aggravation by inhibiting miR-320a-3p targeting BMP6.

Diabetic nephropathy is a common complication of diabetes, accumulating evidence underscores the pivotal role of tubulointerstitial fibrosis in the progression of diabetic nephropathy. However, the underlying mechanisms remain incompletely understood. Although the mechanisms in diabetic nephropathy fibrosis have been the focus of many studies, only limited information is currently available concerning microRNA regulation in tubulointerstitial fibrosis. In this study, we aimed to investigate the roles of miR-320a-3p and bone morphogenetic protein-6 (BMP6) in tubulointerstitial fibrosis. After inducing fibrosis with high glucose in HK-2 cells, we found that miR-320a-3p is significantly up-regulated, whereas BMP6 is markedly down-regulated. These changes suggest close link between miR-320a-3p and BMP6 in tubulointerstitial fibrosis. To elucidate this phenomenon, miR-320a-3p mimic, inhibitor and siBMP6 were employed. We observed in miR-320a-3p mimic group the fibrosis marker include alpha smooth muscle actin and type I collagen was significantly up-regulated, whereas BMP6 exhibited the opposite trend. Additionally, we found icariin could alleviate tubulointerstitial fibrosis by downregulation the miR-320a-3p expression. In conclusion, miR-320a-3p promotes tubulointerstitial fibrosis during the development of DN by suppressing BMP signal pathway activity via inhibiting BMP6 expression. Suggesting that miR-320a-3p represents a potential therapeutic target for tubulointerstitial fibrosis induced by diabetic nephropathy.

Research on correlation between dynamic resilient modulus and CBR of coarse-grained chlorine saline soil.

A large area of coarse-grained saline soil is distributed in saline soil areas, and chlorine saline soil with a high salt content is a typical representative. The dynamic resilient modulus was accurately predicted using the California-bearing ratio (CBR) value to determine the relationship between the dynamic resilient modulus of coarse-grained chloride saline soil and its CBR value. Indoor dynamic triaxial tests and CBR tests were conducted to investigate the evolution of the dynamic resilient modulus (MR) and CBR of coarse-grained chlorine saline soil under the influence of the stress level, water content, and salt content. The test results showed that the dynamic resilient modulus increased with an increase in the confining pressure and bulk stress and decreased as the deviator stress increased; however, the CBR increased with an increase in the corresponding unit pressure. The higher the salt and water contents, the more obvious the influence of stress on the dynamic resilient modulus and CBR value. Under the same stress level, the decrease in the dynamic resilient modulus and CBR gradually increased with increasing salt and moisture content, and the effect of salt tended to be more significant than that of water. Based on the correlation between the dynamic resilient modulus and CBR revealed by the experiment, a more widely applicable model was selected from the existing theoretical models related to CBR for the regression analysis of the test data, and a prediction model of the dynamic resilient modulus based on the CBR value was proposed (MR = 21.06CBR0.52). This prediction model had a high correlation coefficient (R2 = 0.893) and could effectively predict the dynamic resilient modulus of coarse-grained chlorine saline soil using CBR values. The results provide a simple and reliable method for determining the design parameters of a coarse-grained saline soil subgrade.

Adaptive Segmentation Algorithm for Subtle Defect Images on the Surface of Magnetic Ring Using 2D-Gabor Filter Bank.

In order to realize the unsupervised segmentation of subtle defect images on the surface of small magnetic rings and improve the segmentation accuracy and computational efficiency, here, an adaptive threshold segmentation method is proposed based on the improved multi-scale and multi-directional 2D-Gabor filter bank. Firstly, the improved multi-scale and multi-directional 2D-Gabor filter bank was used to filter and reduce the noise on the defect image, suppress the noise pollution inside the target area and the background area, and enhance the difference between the magnetic ring defect and the background. Secondly, this study analyzed the grayscale statistical characteristics of the processed image; the segmentation threshold was constructed according to the gray statistical law of the image; and the adaptive segmentation of subtle defect images on the surface of small magnetic rings was realized. Finally, a classifier based on a BP neural network is designed to classify the scar images and crack images determined by different threshold segmentation methods. The classification accuracies of the iterative method, the OTSU method, the maximum entropy method, and the adaptive threshold segmentation method are, respectively, 85%, 87.5%, 95%, and 97.5%. The adaptive threshold segmentation method proposed in this paper has the highest classification accuracy. Through verification and comparison, the proposed algorithm can segment defects quickly and accurately and suppress noise interference effectively. It is better than other traditional image threshold segmentation methods, validated by both segmentation accuracy and computational efficiency. At the same time, the real-time performance of our algorithm was performed on the advanced SEED-DVS8168 platform.

Athermal panoramic annular lens design with a thermal analysis method.

An athermal 360∘×(30∘-100∘) and F/3.5 panoramic annular lens (PAL) system is designed. Through the optical mechanical thermal analysis results based on finite element analysis (FEA), it is expected that the system will have excellent performance under extreme temperature fluctuations. Simulation shows that the system is thermally insensitive in the temperature range from -40∘ C to 60°C, consistently providing great imaging capability with the modulation transfer function (MTF) value at 133 lp/mm greater than 0.3. The proposed design and analysis workflow contains an evaluation of thermal optical performance with a higher accuracy, thus having significance in future athermal optical design. We expect the designed PAL system to have a broad application prospect in the field of outdoor applications, including automatic navigation of vehicles and all-weather surveillance systems.

Amphiphilic HZSM-5 for Cyclopentene Hydration at the Liquid-Liquid Interface in Pickering Emulsion.

Zeolite is considered an ideal catalyst for olefin hydration due to its high specific surface area and abundant acid sites. However, the immiscibility of the water-oil two phases in olefin hydration limits mass transfer, and the side reaction of etherification occurs acutely, resulting in a low yield of alcohol. Thus, water-oil amphiphilic HZSM-5 was prepared by sulfonating silanized zeolite. The successful introduction of organic and sulfonic acid groups is demonstrated by FT-IR, TG, and water contact angles. Amphiphilic HZSM-5 can stabilize the Pickering emulsion and catalyze cyclopentene hydration at the phase interface. In addition, NH3-TPD and Py-IR show that the amount of strong BroÌ·nsted acid sites of zeolites increases significantly after sulfonation. This facilitates the rate-determining step of cyclopentene activation by H+ to form carbocation. Moreover, the nucleophilic side reactions are inhibited by a high concentration of H+. Finally, under the optimized reaction condition, the conversion of cyclopentene can achieve 5.066% with a selectivity of 85.37% to cyclopentanol, which almost reaches the reaction equilibrium.

Molecular simulation on compatibility and mechanisms of SBS and PTW polymer modifiers in asphalt binder.

CONTEXT: Ultrathin overlays are preventive maintenance measures; the tensile and shear stresses generated inside a structural layer under vehicle load are greater than those of conventional thickness asphalt pavement. Therefore, asphalt binders must use high-viscosity and elasticity unique cementing materials to ensure stability. To investigate the modification mechanism of styrene-butadiene-styrene (SBS)/ethylene-butyl acrylate-glycidyl methacrylate copolymer (PTW) high-viscosity modified asphalt binder suitable for ultrathin overlays, the compatibility and molecular behavior of SBS/PTW high-viscosity modified asphalt binder were analyzed by the molecular dynamics (MD) method. These research results provide a reference for preparing ultrathin overlay high-performance composite modified asphalt binder. METHODS: SBS molecular models, PTW molecular models, asphalt binder molecular models, SBS/asphalt binder blend systems, and SBS/PTW/asphalt binder blend systems were sequentially constructed using Materials Studio (MS) software. The compatibility of SBS, PTW, and SBS/PTW with asphalt binder and the diffusion coefficients of SBS, PTW, and SBS/PTW in the asphalt binder were investigated separately using the MD method. The mechanical properties and molecular behavior of SBS, PTW, and SBS/PTW blended with asphalt binder were studied. The research results indicate that the compatibility of PTW with asphalt binder is better than that of SBS with asphalt binder. PTW can effectively decrease the solubility parameter of asphalt binder and improve the compatibility between SBS and asphalt binder. PTW effectively improves the diffusion coefficient and interaction energy of SBS in asphalt binder by up to 29% and 83%. In addition, SBS/PTW had a significant positive effect on the mechanical properties of the asphalt binders, increasing the elastic modulus (E), bulk modulus (K), and shear modulus (G) of the asphalt binder by 4.6%, 9.5%, and 3.5%, respectively, compared to SBS. The results indicate that the SBS/PTW modified asphalt binder composite can significantly improve the high-temperature shear resistance of asphalt binder. Meanwhile, SBS and PTW improve the self-aggregation behavior between asphalt binder component molecules. The distance between the center of mass of asphalt binder and resin system molecules is increased. PTW enhances the extensibility of the branched chains of asphalt binder component molecules and improves the interaction between asphalt binder components and the chains. This further enhances the density and stability of the asphalt binder molecular structure system, improving the physical properties of the asphalt binder.

Ultra-wide angle panoramic imaging system based on a multiplexed reflective surface.

We propose an ultra-wide angle panoramic imaging system based on a multiplexed reflective surface, which consists of a panoramic head unit (PHU) and the relay lens group. The multiplexed reflective surface is applied in the PHU to reflect light from glass and air for imaging, obtaining the front and rear view channels, respectively. With a field of view (FoV) of 360∘×(35∘-120∘) and an f-number of four, this system has good image quality and relative illumination in the FoV. In addition, it has loose tolerance requirements and a diameter ratio of 7.2, reducing the difficulty of manufacturing and assembly. This optical system architecture provides a promising solution for panoramic perception over a wider FoV.

Multicenter, randomized controlled, open label evaluation of the efficacy and safety of arbidol hydrochloride tablets in the treatment of influenza-like cases.

OBJECTIVE: To study the efficacy and safety of arbidol hydrochloride tablets as a treatment for influenza-like diseases. METHODS: In this multicenter, randomized, controlled, open label study, a total of 412 influenza-like cases were collected from 14 hospitals in seven regions of Hebei Province from September 2021 to March 2022. Patients were randomly divided into two groups. The control group (n = 207) were administered oseltamivir phosphate capsules for five days and the experimental group (n = 205) were administered arbidol hydrochloride tablets for five days. The primary endpoint was the time to normal body temperature, and the secondary endpoints included the time to remission of influenza symptoms, incidence of influenza-like complications, and incidence of adverse reactions. RESULTS: Before treatment, there was no significant difference between the two groups in general conditions, blood routine, body temperature, or symptom severity. After treatment, there was no significant difference between the groups in the mean time to fever remission (59.24 h ± 25.21 vs. 61.05 h ± 29.47) or the mean time to remission of influenza symptoms (57.31 h ± 30.19 vs. 62.02 h ± 32.08). Survival analyses using Log-rank and Wilcoxon bilateral tests showed that there was no significant difference in fever relief time or influenza symptom relief time between the two groups. Regarding the incidence of complications and adverse events, there was only one case of tracheitis, one case of nausea, one case of vomiting, and one case of dizziness in the control group. In the experimental group, there was one case of nausea, one case of vomiting, and one case of drowsiness. In addition, one patient in the control group was hospitalized for urinary calculi. CONCLUSION: There was no significant difference between the patients with influenza-like cases treated with arbidol hydrochloride tablets and those treated with oseltamivir phosphate capsules. Further, the patients treated with arbidol hydrochloride tablets had fewer adverse reactions, and thus, the tablets were safe to use.

Improving fast auto-focus with event polarity.

Fast and accurate auto-focus in adverse conditions remains an arduous task. The emergence of event cameras has opened up new possibilities for addressing the challenge. This paper presents a new high-speed and accurate event-based focusing algorithm. Specifically, the symmetrical relationship between the event polarities in focusing is investigated, and the event-based focus evaluation function is proposed based on the principles of the event cameras and the imaging model in the focusing process. Comprehensive experiments on the public event-based autofocus dataset (EAD) show the robustness of the model. Furthermore, precise focus with less than one depth of focus is achieved within 0.004 seconds on our self-built high-speed focusing platform. The dataset and code will be made publicly available.

General design algorithm for stray light suppression of a panoramic annular system.

In this work, a universal algorithm for designing a panoramic annular lens (PAL) system free from stray light is proposed. The impact of a given stray light path to the optical system could be estimated without running a full stray light analysis process, which allows designers to eliminate troublesome stray light paths by optimizing lens parameters at an early stage of optical design. A 360° ×(40°-100°) PAL system is designed and implemented to verify the proposed method. Simulation shows that the point source transmittance (PST) decreases by 2 orders of magnitude at a specific field-of-view (FoV) range after optimizing the system. Experimental results show perfect consistency with the simulation predictions, which indicate that two types of stray light are totally eliminated in the demonstrated system. This stray light analysis and suppression method provides a promising approach for the research and development of ultra-wide angle high performance optical systems.

Experimental Study on the Strength and Hydration Products of Cement Mortar with Hybrid Recycled Powders Based Industrial-Construction Residue Cement Stabilization of Crushed Aggregate.

The strength-formation mechanism for industrial-construction residue cement stabilization of crushed aggregate (IRCSCA) is not clear. To expand the application range for recycled micro-powders in road engineering, the dosages of eco-friendly hybrid recycled powders (HRPs) with different proportions of RBP and RCP affecting the strengths of cement-fly ash mortar at different ages, and the strength-formation mechanism, were studied with X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed that the early strength of the mortar was 2.62 times higher than that of the reference specimen when a 3/2 mass ratio of brick powder and concrete powder was mixed to form the HRP and replace some of the cement. With increasing HRP content substituted for fly ash, the strength of the cement mortar first increased and then decreased. When the HRP content was 35%, the compressive strength of the mortar was 1.56 times higher than that of the reference specimen, and the flexural strength was 1.51 times higher; XRD and SEM studies of the hydrated cement mixed with HRP showed that the amount of CH in the cement paste was reduced by the pozzolanic reaction of HRP at later hydration ages, and it was very useful in improving the compactness of the mortar. The XRD spectrum of the cement paste made with HRP indicated that the CH crystal plane orientation index R, with a diffraction angle peak of approximately 34.0, was consistent with the cement slurry strength evolution law, and this research provides a reference for the application of HRP to produce IRCSCA.

Design of a compact triple-channel panoramic stereo imaging system.

We propose a compact form of the triple-channel panoramic annular lens (PAL) with a stereo field and no central blind area based on polarization technology, which solves the problem that the traditional stereo panoramic system always has a large and complex mirror in front to reflect light. Based on the traditional dual-channel structure, we apply polarization technology to the first reflective surface to create a third channel for the stereovision. The field of view (FoV) of the front channel is 360° × (0° - 40°), the FoV of the side channel is 360° × (40° - 105°) and the stereo FoV is 360° × (20° - 50°). The Airy radii of the front channel, the side channel, and the stereo channel are 3.374 µm, 3.372 µm, and 3.360 µm, respectively. The modulation transfer function at 147 lp/mm is greater than 0.13 in the front and stereo channels and greater than 0.42 in the side channel. The F - θ distortion of all FoVs is less than 10%. This system shows a promising way to achieve stereovision without adding complex structures on the original basis.

Optical trapping of two different microparticles by a double-tapered fiber probe.

We theoretically and experimentally study the optical trapping of two different microparticles by a double-tapered optical fiber probe (DOFP) which is fabricated by the interfacial etching method. A SiO2 microsphere and a yeast, or two SiO2 microspheres with different diameters, are trapped. We calculate and measure the trapping forces on the two microparticles, discuss the impacts of the geometrical size and refractive index on the trapping forces. Both the theoretical calculation and experimental measurements indicate that if the two particles have the same refractive index, the larger the second particle is, the larger the trapping force is. Whereas, if the two particles have the same geometrical size, the smaller the refractive index is, the lager trapping force is. Trapping and manipulation of different multiple microparticles by a DOFP enhance the application of optical tweezers, especially in biomedical engineering and material science.

Design of stereo imaging system with a panoramic annular lens and a convex mirror.

Panoramic stereo imaging system can not only provide panoramic images to obtain more information, but also obtain the depth information of the target object, and it has broad application prospects in robot navigation, road planning, and obstacle avoidance. A new panoramic stereo imaging system combined with a panoramic annular lens (PAL) and a convex mirror is proposed. It provides a large panoramic vision up to 360°× (30°âˆ¼150°) and, to the best of our knowledge, the entire FOV is the largest in the existing literature. Meanwhile, the stereo field of view is 35°.

Compact and lightweight panoramic annular lens for computer vision tasks.

We propose a focal power distribution theory for the design of a compact panoramic annular lens (PAL) system based on Petzval sum correction. The system has a large field of view (FoV) of 360° ×(25°-100°). Its total length is 29.2 mm and weight is only 20 g. The proposed compact PAL system achieves large FoV and loose tolerances while maintaining small volume and low cost. It solves the shortcomings of traditional PAL systems that cannot be mounted on miniaturized portable devices due to their large volume and weight. We equip the compact PAL system with a novel and customized image enhancement model: PAL-Restormer to achieve better imaging quality. The produced images are further evaluated in various panoramic environment perception tasks. Extensive experiments show the promising potential of our proposed compact PAL system for the applications in wearable devices and mobile robots.

Fast testing of partial camera lenses based on a liquid crystal spatial light modulator.

Today, there are strict requirements for the quality inspection of mobile phone cameras, as the design tolerance is getting critically tighter. In order to avoid unnecessary disposal of lens components when testing and assembling the complete cameras, testing the quality of each single lens group in advance before the final assembly is effective. However, as part of a whole camera, a single lens group cannot generate a sharp image independently; it needs to be combined with other elements in the testing system and assembled precisely. In order to address this challenge, we propose a fast testing method based on spatial light modulators (SLMs). By taking advantage of the programmable feature of the SLM, the assembly misalignments caused by fixing the lens group to be tested into the testing system are dynamically scanned and compensated at a fast speed. A design criterion of the phase map pattern to be loaded on the SLM is also verified by simulation and is applied on the testing system. In this way, the proposed method significantly reduces the positioning requirement of the lens under test, and thus improves efficiency. The passed yield of tested lens groups reaches 92.6%.

Association of Blood Pressure Indices with Right and Left Cardio-Ankle Vascular Index (CAVI) and Its Mathematically Corrected Form (CAVI0) for the Evaluation of Atherosclerosis.

BACKGROUND AND OBJECTIVES: The cardio-ankle vascular index (CAVI) is an index for arterial stiffness that is theoretically independent of blood pressure. CAVI0 is the mathematically corrected formula of CAVI that has been claimed to be less dependent on blood pressure changes. The association of right and left CAVI and CAVI0 with blood pressure indices can reveal the importance of considering the blood pressure of the patient despite their theoretical independency. In this study, we assessed the right and left CAVI and CAVI0 and evaluated the main effect of blood pressure indices on them with respect to age. MATERIALS AND METHODS: We collected the following data of 136 community-dwelling individuals: age; sex; weight; height; body mass index; right and left CAVI and CAVI0; and systolic (SBP), diastolic (DBP), and mean blood pressure (MBP). The association of right and left CAVI and CAVI0 with blood pressure indices was evaluated using regression analysis. RESULTS: Regression analysis revealed that SBP, DBP, and MBP were associated with right and left CAVI (independent of age). Moreover, SBP was associated with both right and left CAVI0 (independent of age), whereas DBP was not associated with right or left CAVI0. CONCLUSION: Right and left arterial stiffness measured using CAVI has no different associations with SBP, DBP, and MBP. Both right and left CAVI0 were independently associated with SBP, whereas neither left nor right CAVI0 was independently associated with DBP. MBP was only associated with the right-side CAVI0 in community-dwelling individuals.