Structural characteristics, antioxidant and hypoglycemic activities of polysaccharides from Mori Fructus based on different extraction methods

The mulberry (Mori Fructus), which is rich in many nutrients needed by the human body, serves as both food and medicine. Polysaccharides, which are considered to be important pharmacological components of mulberry, have received a lot of study for their structure and biological activity. In this study, six mulberry fruit polysaccharides (MFPs) were extracted by different extraction methods, and their physicochemical structures, antioxidant, and hypoglycemic biological activities were investigated and compared. According to the findings, MFP-III exhibited the best α-glucosidase and α-amylase inhibition, whereas MFP-IV had the strongest scavenging activity against DPPH and ABTS. Scanner electron microscopy (SEM) and high-performance liquid chromatography (HPLC) analysis showed that the apparent morphology and monosaccharide content of MFP were significantly impacted by the different extraction techniques. The results of experiments using Congo red, Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance (NMR), thermogravimetric analysis (TG), and the Congo red experiment showed that the MFP functional groups, glycosidic bonds, triple helix structure, and thermal stability were not significantly different between the extraction methods. According to the aforementioned research, various extraction methods had different effects on the chemical composition and biological activity of mulberry polysaccharides. This information can provide a scientific basis for selecting suitable extraction methods to obtain mulberry polysaccharides with ideal biological activity

Freeway Deceleration Lane Lengths Effects on Traffic Safety and Operation

Until now, the findings of impacts of deceleration lane lengths on safety were not quite consistent or were even contradictory. A comprehensive study was needed to have a better understanding of the effects of different deceleration lane lengths on traffic safety and operations. This study has three objectives: (1) evaluate the safety performance of different deceleration lane lengths at freeway diverge areas; (2) examine the operational effects of deceleration lane lengths for two design types (one-lane exits with parallel/tapered designs and two-lane exits with parallel design); and (3) select optimal deceleration lane lengths by combining the results from safety and operation aspects. A total of 218 sites, categorized into nine groups, were selected for the crash analysis. Additionally, 360 simulation models were developed for different scenarios by the combination of the exit types (one-lane exits/two-lane exits), design speeds, exiting volumes, and number of through-lanes. The safety and operational analysis results suggest that (1) for one-lane exits, a minimum deceleration length of 500 ft is essential for the design speed of 55 mph, 600 ft for the design speeds of 60 and 65 mph, and 700 ft for the design speed of 70 mph; (2) for two-lane exits, the minimum deceleration length of 500 ft is suggested for the design speeds of 55 mph and 60 mph, 600 ft for the design speeds of 65 and 70 mph; and (3) for both one-lane and two-lane exits, deceleration lane lengths longer than 700 ft are not recommended from a safety perspective. The results of this study could be used as a supplementary to the current design guideline

Polycyclic aromatic hydrocarbons (PAHs) in indoor dusts of Guizhou, southwest of China: status, sources and potential human health risk.

Polycyclic aromatic hydrocarbons (PAHs) were analyzed for 136 indoor dust samples collected from Guizhou province, southwest of China. The ∑18PAHs concentrations ranged from 2.18 μg•g-1 to 14.20 μg•g-1 with the mean value of 6.78 μg•g-1. The highest Σ18PAHs concentration was found in dust samples from orefields, followed by city, town and village. Moreover, the mean concentration of Σ18PAHs in indoor dust was at least 10% higher than that of outdoors. The 4-6 rings PAHs, contributing more than 70% of ∑18PAHs, were the dominant species. PAHs ratios, principal component analysis with multiple linear regression (PCA-MLR) and hierarchical clustering analysis (HCA) were applied to evaluate the possible sources. Two major origins of PAHs in indoor dust were identified as vehicle emissions and coal combustion. The mean incremental lifetime cancer risk (ILCR) due to human exposure to indoor dust PAHs in city, town, village and orefield of Guizhou province, China was 6.14×10-6, 5.00×10-6, 3.08×10-6, 6.02×10-6 for children and 5.92×10-6, 4.83×10-6, 2.97×10-6, 5.81×10-6 for adults, respectively

Deterioration Mechanisms and Advanced Inspection Technologies of Aluminum Windows

Aluminum windows are crucial components of building envelopes since they connect the indoor space to the external environment. Various external causes degrade or harm the functioning of aluminum windows. In this regard, inspecting the performance of aluminum windows is a necessary task to keep buildings healthy. This review illustrates the deterioration mechanisms of aluminum windows under various environmental conditions with an intention to provide comprehensive information for developing damage protection and inspection technologies. The illustrations reveal that moisture and chloride ions have the most detrimental effect on deteriorating aluminum windows in the long run, while mechanical loads can damage aluminum windows in a sudden manner. In addition, multiple advanced inspection techniques potential to benefit assessing aluminum window health state are discussed in order to help tackle the efficiency problem of traditional visual inspection. The comparison among those techniques demonstrates that infrared thermography can help acquire a preliminary defect profile of inspected windows, whereas ultrasonic phased arrays technology demonstrates a high level of competency in analyzing comprehensive defect information. This review also discusses the challenges in the scarcity of nanoscale corrosion information for insightful understandings of aluminum window corrosion and reliable window inspection tools for lifespan prediction. In this regard, molecular dynamics simulation and artificial intelligence technology are recommended as promising tools for better revealing the deterioration mechanisms and advancing inspection techniques, respectively, for future directions. It is envisioned that this paper will help upgrade the aluminum window inspection scheme and contribute to driving the construction of intelligent and safe cities

Tree Species Classification of Backpack Laser Scanning Data Using the PointNet++ Point Cloud Deep Learning Method

To investigate forest resources, it is necessary to identify the tree species. However, it is a challenge to identify tree species using 3D point clouds of trees collected by light detection and ranging (LiDAR). PointNet++, a point cloud deep learning network, can effectively classify 3D objects. It is important to establish high-quality individual tree point cloud datasets when applying PointNet++ to identifying tree species. However, there are different data processing methods to produce sample datasets, and the processes are tedious. In this study, we suggest how to select the appropriate method by designing comparative experiments. We used the backpack laser scanning (BLS) system to collect point cloud data for a total of eight tree species in three regions. We explored the effect of tree height on the classification accuracy of tree species by using different point cloud normalization methods and analyzed the effect of leaf point clouds on classification accuracy by separating the leaves and wood of individual tree point clouds. Five downsampling methods were used: farthest point sampling (FPS), K-means, random, grid average sampling, and nonuniform grid sampling (NGS). Data with different sampling points were designed for the experiments. The results show that the tree height feature is unimportant when using point cloud deep learning methods for tree species classification. For data collected in a single season, the leaf point cloud has little effect on the classification accuracy. The two suitable point cloud downsampling methods we screened were FPS and NGS, and the deep learning network could provide the most accurate tree species classification when the number of individual tree point clouds was in the range of 2048–5120. Our study further illustrates that point-based end-to-end deep learning methods can be used to classify tree species and identify individual tree point clouds. Combined with the low-cost and high-efficiency BLS system, it can effectively improve the efficiency of forest resource surveys

Development of a Frequency-Adjustable Tuned Mass Damper (FATMD) for Structural Vibration Control

The tuned mass damper (TMD) can be applied to suppress earthquake, wind, and pedestrian- and machine-induced vibration in factory buildings or large span structures. However, the traditional TMD with a fixed frequency will not be able to perform effectively against the frequency variations in multiple hazards. This paper proposed a frequency-adjustable tuned mass damper (FATMD) to solve this limitation of current TMD. The FATMD presented in this paper is composed of a simple assembly consisting of a supported beam with a mass, in which the frequency of the FATMD is changed by adjusting the span of the beam. The kinematic equation of a single degree of freedom (SDOF) structure installed with an FATMD is established to analyze the effect of the damping ratio, mass ratio, and stiffness on the vibration damping. The fundamental frequency of the FATMD at different spans is verified by simulation and experiments. Forced vibration experiments with different excitation frequencies are also conducted to verify the performance of the FATMD. The results show that the proposed FATMD can effectively suppress the vertical vibration of structures at different excitation frequencies, including frequencies at a range higher than what a traditional TMD may not be able to suppress. Additionally, the proposed FATMD is applied to a long-span pedestrian bridge which vibrates frequently due to the walking of pedestrians, the running of escalators, and earthquakes. The numerical results indicate that the FATMD can effectively reduce the vertical vibration of the pedestrian bridge under the excitations of pedestrians, escalators, and earthquakes

Separation of Mori fructus Polysaccharides and Screening of Bioactive Fractions Based on Membrane Technology

Membrane technology was used for the graded separation of Mori fructus polysaccharides, and its antioxidant, hypoglycemic, anti-allergic and in vitro alcohol dehydrogenase activities were studied. The Mori fructus polysaccharides were carried out by hot water extraction using ultrafiltration membranes with pore sizes of 300, 50, 5 and 1 kDa, respectively, as MFP300, MFP50, MFP5 and MFP1. The differences in the main components, antioxidant activity, hypoglycemic activity, antiallergic activity and in vitro ethanol dehydrogenase activity of Mori fructus polysaccharide fractions separated by ultrafiltration membranes of four pore sizes were compared. The results showed that the major components and biological activities of the four polysaccharides showed some differences. The total sugar content of MFP1, MFP5, MFP50 and MFP300 were 46.34%, 68.45%, 48.60% and 66.32%, respectively, while the glyoxylate content were 3.34%, 22.78%, 16.11% and 21.48%, respectively, and the reducing sugar content were 16.51%, 6.03%, 7.90% and 6.67%, respectively. Bioactivity screening showed that MFP300 scavenged DPPH radicals and ABTS+ radicals with IC50 values of 0.2235 and 0.2979 mg·mL−1, respectively, inhibited hyaluronidase with IC50 values of 0.6634 mg·mL−1, and activated in vitro ethanol dehydrogenase with IC50 values of 10.2646 mg·mL−1. MFP300 was exhibited the best antioxidant, anti-allergic and in vitro ethanol dehydrogenase activities compared with the other three components. Compared with the other three components, MFP1 exhibited the best hypoglycemic activity with IC50 values of 0.7944 and 4.6419 mg·mL−1 for its ability to inhibit α-glucosidase and α-amylase, respectively. In conclusion, there were some differences in the main components and biological activities of Mori fructus polysaccharides obtained by membrane classification and separation, which could provide a theoretical basis for the improvement and upgrading of Mori fructus polysaccharide classification technology and the study of the ''structure-effect'' relationship of Mori fructus polysaccharides

Clustering analysis diagram.

<p>Clustering analysis diagram.</p