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Fourier transform infrared (FT-IR) spectroscopy has attracted great attention in the field of disease diagnostics for many years. Yet, the clinical translation of FT-IR spectroscopy has been rather slow because of several bottlenecks. This work explores the potential of aluminum foil-assisted attenuated total reflectance-FT-IR (ATR-FT-IR) spectroscopy, which is a simple and economical FT-IR sampling technique, to detect acute kidney injury (AKI) induced by gentamicin in a rat model. It was found that partial least squares-discriminant analysis (PLS-DA) could successfully discriminate between the AKI status and the healthy status with the plasma samples of the rats. An in-depth discussion on the advantages of aluminum-foil-assisted ATR-FT-IR spectroscopy in FT-IR-based disease diagnostics is also provided., Fourier transform infrared (FT-IR) spectroscopy is a rapid, non-invasive, and label-free analytical technology and has attracted great attention in the field of disease diagnostics for many years (1-6). As a [...]

Heavy rainfall is the main factor inducing the failure of loess slopes. However, the failure mechanism and mode of terraced loess slopes under heavy rainfall have not been well investigated and understood. This paper presents the experimental study on the deformation and failure of terraced loess slopes with different gradients under extreme rainfall conditions. The deformation and failure processes of the slope and the migration of the wetting front within the slope during rainfall were captured by the digital cameras installed on the top and side of the test box. In addition, the mechanical and hydrological responses of the slope, including earth pressure, water content, pore water pressure, and matric suction, were monitored and analyzed under rainfall infiltration and erosion. The experimental study shows that the deformation and failure of terraced loess slopes under heavy rainfall conditions exhibit the characteristic of progressive erosion damage. In general, the steeper the slope, the more severe the deformation and failure, and the shorter the time required for erosion failure. The data obtained from sensors embedded in the slope can reflect the mechanical and hydraulic characteristics of the slope in response to rainfall. The earth pressure and pore water pressure in the slope exhibit a fluctuating pattern with continued rainfall. The failure mode of terraced loess slopes under extreme rainfall can be summarized into five stages: erosion of slope surface and formation of small gullies and cracks, expansion of gullies and cracks along the slope surface, widening and deepening of gullies, local collapse and flow-slip of the slope, and large-scale collapse of the slope. The findings can provide preliminary data references for researchers to better understand the failure characteristics of terraced loess slopes under extreme rainfall and to further validate the results of numerical simulations and analytical solutions. [ABSTRACT FROM AUTHOR]

Simple Summary: With the transformation of the breeding industry towards a healthy breeding model, the application of green feed additives in pig production is gradually increasing. Many plant polysaccharides are widely used as safe and green additives in animal production. Boron may be a necessary trace element for animals and its application in animal husbandry is also increasing. The study on the application effect of the combined addition of plant polysaccharides and boron in fatteners production performance, immune function, antioxidant function, digestive function and harmful substance emissions is of great significance for the rational use of both. This study added boron and different types of plant polysaccharides to the diet in the form of boric acid and found that the combined addition of boric acid and plant polysaccharides can improve the production performance and antioxidant function of fatteners by enhancing the activity of intestinal digestive enzymes and reducing the content of harmful substances such as heavy metals and harmful gases in feces and urine, thereby effectively improving healthy growth and reducing environmental pollution today. The experiment aimed to investigate the effects of plant polysaccharides combined with boric acid on digestive function, immune function and harmful gas and heavy metal contents in the faeces of fatteners. For this study, 90 healthy crossbred fatteners were selected and randomly divided into five groups: the control group was fed with a basal diet (Con); experimental group I was fed with basal diet + 40 mg/kg boric acid (BA); experimental group II was fed with basal diet + 40 mg/kg boric acid + 400 mg/kg Astragalus polysaccharides (BA+APS); experimental group III was fed with basal diet + 40 mg/kg boric acid + 200 mg/kg Ganoderma lucidum polysaccharides (BA+GLP); and experimental group IV was fed with basal diet + 40 mg/kg boric acid + 500 mg/kg Echinacea polysaccharides (BA+EPS). Compared with Con, the average daily gain (ADG), the trypsin activities in the duodenum and jejunum, the IL-2 levels in the spleen, the T-AOC activities and GSH-Px contents in the lymph node of fattening were increased in the BA group (p < 0.05), but malondialdehyde content in the lymph and spleen, and the contents of NH3, H2S, Hg, Cu, Fe and Zn in the feces and urine were decreased (p < 0.05). Compared with the BA, the ADG, gain-to-feed ratio (G/F), the trypsin and maltase activities in the duodenum and jejunum were increased in the BA+APS (p < 0.05), and the T-SOD activities in the spleen and T-AOC activities in the lymph node were also increased (p < 0.05), but the H2S level was decreased in the feces and urine (p < 0.05). Compared with the BA, the ADG, G/F and the trypsin and maltase activities in the duodenum were increased in the BA+GLP and BA+EPS (p < 0.05), the activities of maltase and lipase in the duodenum of fatteners in the BA+GLP and the activities of trypsin, maltase and lipase in the BA+EPS were increased (p < 0.05). Gathering everything together, our findings reveal that the combined addition of boric acid and plant polysaccharides in the diet of fatteners synergistically improved their growth performance and immune status. That may be achieved by regulating the activity of intestinal digestive enzymes, improving the antioxidant function and then promoting the digestion and absorption of nutrients. Furthermore, the above results reduce the emission of harmful gases and heavy metals in feces and urine. [ABSTRACT FROM AUTHOR]

Simple Summary: Bordetella bronchiseptica (B. bronchiseptica) is a severe zoonotic pathogen widespread in aquaculture environments. However, information on the distribution and resistance of this pathogen remains scarce in pig farms. This study isolated and analyzed B. bronchiseptica from pig farms in central China and revealed a high frequency of resistance to this pathogen, with most strains forming biofilms. In addition, a B. bronchiseptica strain with a heteroresistant phenotype to gentamicin was isolated, which is a rare case and requires vigilance. This study enhances our understanding of the biological characteristics, such as the distribution and resistance, of B. bronchiseptica in pig farms in central China. This can provide valuable data for future related research and pathogen prevention and control. Bordetella bronchiseptica is a significant contributor to respiratory disease in pigs, leading to substantial economic losses in the swine industry worldwide. We isolated 52 B. bronchiseptica strains from 542 samples collected from pigs with atrophic rhinitis and bronchopneumonia in central China. Multi-locus sequence typing identified two prevalent sequence types: ST6 (69.23%) and ST7 (30.77%). PCR-based detection of seven virulence genes (fhaB, prn, cyaA, dnt, bteA, fla, and bfrZ) revealed that six of these genes were present in over 90% of the isolates, with bfrZ being the exception at 59.62%. Antimicrobial susceptibility testing, performed using the K-B method, demonstrated high sensitivity to enrofloxacin, polymyxin, and doxycycline but a notable resistance to tylosin, trimethoprim, tobramycin, ciprofloxacin, and amikacin. Remarkably, 86.54% of the isolates exhibited a multidrug-resistant phenotype. Notably, we successfully screened a strain of B. bronchiseptica with a heteroresistance phenotype to gentamicin using population analysis profiling, which is a rare case. Biofilm-formation assays indicated that 96.15% of the isolates possessed biofilm-forming capabilities. These findings provide crucial insights into the prevalence of B. bronchiseptica in central China, facilitating the development of effective preventive measures to safeguard both animal and human health. [ABSTRACT FROM AUTHOR]

The design of aerospace systems is recognized as a complex interdisciplinary process. Many studies have shown that the exchange of information among multiple disciplines often results in strong coupling and nonlinearity characteristics in system optimization. Meanwhile, inevitable multi-source uncertainty factors continuously accumulate during the optimization process, greatly compromising the system's robustness and reliability. In this context, uncertainty-based multidisciplinary design optimization (UMDO) has emerged and has been preliminarily applied in aerospace practices. However, it still encounters major challenges, including the complexity of multidisciplinary analysis modeling, and organizational and computational complexities of uncertainty analysis and optimization. Extensive research has been conducted recently to address these issues, particularly uncertainty analysis and artificial intelligence strategies. The former further enriches the UMDO technique, while the latter makes outstanding contributions to addressing the computational complexity of UMDO. With the aim of providing an overview of currently available methods, this paper summarizes existing state-of-the art UMDO technologies, with a special focus on relevant intelligent optimization strategies. [ABSTRACT FROM AUTHOR]

Understanding land use/cover change (LUCC) and landscape ecological risk change in the context of future climate warming can help adjust socio-economic development policies, optimize regional ecological security patterns, and promote green and low-carbon development on the one hand and provide important supplements and improvements for research in related fields on the other. Taking Urumqi as the study area, based on the Coupled Model Intercomparison Project Phase 6 (CMIP6) multi-modal ensemble data, we used the coupled system dynamics (SD) model and patch-generation land use simulation (PLUS) model to simulate land use change under three SSP-RCP scenarios in 2020–2060, and we predicted trends of landscape ecological risk change in this 40-year period by using the landscape ecological risk index (LERI). The results indicate that woodland and grassland significantly increase under the SSP126 scenario. Unused land is larger in the SSP245 scenario. The expansion trend of construction land toward cultivated land is most obvious in the SSP585 scenario; additionally, the area of water increases more distinctly in this scenario. The overall landscape ecological risk under the three SSP-RCP scenarios is reduced to different degrees; in particular, the risk level of urban built-up areas and nature reserves decreases remarkably, and the area of the highest risk zones of unused land is also gradually narrowed. By 2060, the average LERI under the SSP126 scenario is the lowest. The study findings can help relevant departments formulate reasonable urban development plans, which are of great theoretical and practical significance for guaranteeing regional ecological security. [ABSTRACT FROM AUTHOR]

There have been three major global outbreaks of acute respiratory disease caused by coronavirus in the last two decades. The ongoing Coronavirus Disease 2019 (COVID-19) first emerged in Wuhan, China, is the most dangerous, which spread to 163 countries and 6 continents and caused a major public health emergency worldwide. The outbreak is caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) originated from bats, which spreads rapidly from human to human. As of 17 March 2020, there have been 179,112 confirmed cases and 7426 deaths worldwide, with a mortality rate of 4.1%. There is currently no effective treatment or approved vaccine, so isolating the source of infection and blocking the routes of transmission is important. In this article, we summarized the worldwide epidemic trend of COVID-19 and discussed its epidemiological characteristics, prevention and control measures. We hope this article could provide experience and help for global epidemic prevention and control. [ABSTRACT FROM AUTHOR]

Photoresponsive surface molecularly imprinted polymers (PSMIPs) with controlled nanoshell thicknesses were synthesized using different amounts of precursor materials to determine the effects of polymer shell layer thickness on the separation and purification of 6‐O‐alpha‐maltosyl‐beta‐cyclodextrin (Mal‐β‐CD). The physicochemical properties and adsorption and desorption capacities of PSMIPs with different shell thicknesses were studied. Interestingly, the uniform thickness of the imprinted polymer shell layer could be adjusted from 10 to 60 nm by varying the amount of polymerization precursors, and the average mesopore diameter of PSMIPs was not significantly affected by shell thickness. However, the removal efficiency and selective capacity of PSMIPs on Mal‐β‐CD were strongly correlated to their shell thickness. The adsorption behavior of PSMIPs on Mal‐β‐CD fitted well with the Langmuir adsorption model and pseudo‐second‐order kinetic model. Based on the obtained results, PSMIPs with a 30‐nm imprinted layer were found to be an excellent adsorbent for Mal‐β‐CD separation, with an adsorption capacity of 18.12 mg/g. They can therefore be used for industrial chromatographic separations of Mal‐β‐CD in the future. Practical Application: This article clearly demonstrated that the shell thickness of core‐shell molecularly imprinted materials affected the degree and rate of cyclodextrin separation. Determining the optimal thickness is of great significance for the material in the separation and purification of cyclodextrin. [ABSTRACT FROM AUTHOR]

Rational design of amyloid-based materials requires structural insight into such materials. Here, we explore the use of a side-chain-based infrared (IR) probe technique combined with atomic force microscopy, Raman spectroscopy, UV-Vis spectroscopy, and thermogravimetric analysis coupled with mass spectrometry to elucidate the structural details of an amyloid nanosheet formed by an Aβ(16–22) variant, KLVXFAK, where X is p-cyanophenylalanine with its side-chain cyano group being an IR probe. Through the structural constraints obtained with the combined tools, we are able to propose a novel structural model for the amyloid nanosheet. The nanosheet can be viewed as a stack of class 7-type steric-zipper-like amyloid structures with a unique sheared intersheet arrangement: the β-sheets are stacked along a zippering axis with each individual β-sheet sheared relative to its adjacent β-sheets by two residues through the cyano–lysine intersheet hydrogen bond. With such a configuration, the side view of the nanosheet is similar to that of a stack of tilted-aligned roof tiles with each individual β-sheet being each tile. In addition, this work provides a nice example of how to utilize the side-chain-based IR probe technique combined with other supplemental tools to build a hierarchical structural model for a complex amyloid assembly. [ABSTRACT FROM AUTHOR]

Six polysaccharide fractions (DOP30, DOP40, DOP50, DOP60, DOP70, and DOP80) were purified successfully from Dendrobium officinale by the ethanol precipitation method, and their physicochemical characterizations and antioxidant properties were investigated by the chemical methods, high performance liquid chromatography (HPLC), UV-vis (UV) and Fourier transform infrared spectroscopy, and 1,1-diphenyl-2-picrylhydrazyl radical scavenging ability, 2,2-azinobis-6-s (3-ethylbenzothiazoline sulfonic acid) (ABTS) radical scavenging activity, hydroxyl radical scavenging activity, and reducing power, respectively. Results estimated their weight-average molecular weight (Mw) to be 361.4, 242.6, 192.3, 100.5, 23.7, and 8.2 kDa, respectively. Mannose and glucose were the major monosaccharide components presenting in the polysaccharide fractions. However, monosaccharide compositions were significantly different among the DOPs, namely, DOPs with a smaller Mw contained more species of monosaccharides. All six polysaccharide fractions displayed antioxidant activities in vitro according to the antioxidant tests, and a small molecular weight of polysaccharides (DOP80 and DOP70) showed stronger antioxidant activities. The present results suggest that DOPs could potentially be used as a natural antioxidant, especially the small molecular weight ones. [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: Dendrobium officinale has been used in China for several thousand years as a health food and has become one of the most expensive tea materials worldwide as a result of extremely scarce resources in the wild and an increasing demand. Hence, it is very important to improve the depth and width of its application. In the present study, the physico‐chemical, surface chemistry and thermal properties of micron range particles and coarse particles prepared by superfine grinding and shear pulverization were investigated. RESULTS: As the particle size decreased, the specific surface area of D. officinale powders increased significantly. Microscopy observations confirmed that superfine grinding effectively changed the original structure of D. officinale. The Fourier transform infrared spectroscopy spectra depicted the characteristic bands shifted in terms of absorbance and/or wave number as the powder particle size decreased. The crystallinity and intensity of the crystal peaks of D. officinale powders increased as the particle size decreased. Moisture sorption isotherms suggested that superfine powders were more unstable as a result of the increase in surface area, as well as the exposure of polar groups. CONCLUSION: The results of the present study suggest that superfine grinding may provide new methods of processing for D. officinale with respect to further enhancement of its application value. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The present study aimed to investigate the effect of different drying methods, i.e., sun drying (SD), hot air drying (AD), vacuum drying (VD), infrared radiation drying (IR), and freeze drying (FD) on the physico-chemical properties of Dendrobium officinale. The results revealed that different drying methods showed significant differences in the color retention, water soluble polysaccharide content, total phenolic content, total flavonoid content, fatty acids, and antioxidant activities. FD, VD, IR and AD led to higher retention of bioactive compounds and better antioxidant activities, and FD showed the best. However, with respect to the water-soluble polysaccharides content, the characteristic components in D. officinale, AD was better than FD. The results showed that the quality of D. officinale depends on the drying method applied. Considering the retention of polysaccharide content and drying processing duration, AD is a promising treatment for D. officinale. [ABSTRACT FROM AUTHOR]

Photoirradiation surface molecularly imprinted polymers for the separation of 6- O-α- d-maltosyl-β-cyclodextrin were synthesized using functionalized silica as a matrix, 4-(phenyldiazenyl)phenol as a light-sensitive monomer, and 6- O-α- d-maltosyl-β-cyclodextrin as a template. Fourier transform infrared spectroscopy results indicated that 4-(phenyldiazenyl)phenol was grafted onto the surface of functionalized silica. The obtained imprinted polymers exhibited specific recognition toward 6- O-α- d-maltosyl-β-cyclodextrin. Equilibrium binding experiments showed that the photoirradiation surface molecularly imprinted polymers obtained the maximum adsorption amount of 6- O-α- d-maltosyl-β-cyclodextrin at 20.5 mg/g. In binding kinetic experiments, the adsorption reached saturation within 2 h with binding capacity of 72.8%. The experimental results showed that the adsorption capacity and selectivity of imprinted polymers were effective for the separation of 6- O-α- d-maltosyl-β-cyclodextrin, indicating that imprinted polymers could be used to isolate 6- O-α- d-maltosyl-β-cyclodextrin from a conversion mixture containing β-cyclodextrin and maltose. The results showed that the imprinted polymers prepared by this method were very promising for the selective separation of 6- O-α- d-maltosyl-β-cyclodextrin. [ABSTRACT FROM AUTHOR]

In herbal markets, an overwhelming majority the D. officinale are sold in spiral or spring form, and this kind of product would lead to the incomplete release of some nutrients. To increase the bioaccessibility of D. officinale, we report a method of pulverisation treatments including general and superfine grinding to reduce the particle size. In comparison with coarse D. officinale, the superfine ground D. officinale with particle sizes of <18 μm resulted in significant higher bulk density, better flowability and greater hydration properties. The protein and polysaccharide solubility of D. officinale increased significantly as its particle size decreased. The extract of D. officinale with a particle size of <18 μm showed that highest total phenolic and total flavonoid contents accompanied with the best antioxidant activity through all antioxidant assays compared with coarse ground D. officinale and D. officinale products. [ABSTRACT FROM AUTHOR]