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Abstract Determination of the fatty acid profile of milk fat generally involves a protocol that comprises total lipid extraction, transesterification and GC analysis. The lipid extraction step is time-consuming and often employs toxic solvents such as chloroform. A novel protocol is presented here that skips the lipid extraction step and allows the determination of fatty acid composition via direct methylation of milk fat isolated after centrifugation of raw milk. This new method is reliable for relative quantification of fatty acids in raw milk fat and offers a much higher throughput compared with the classical methods. [ABSTRACT FROM AUTHOR]

Three acid- and alkaline-catalysed transesterification methods were compared with the aim to validate a simple yet reliable protocol for fatty acid (FA) profiling of milk fat. While both the acid- and alkaline-catalysed methods were able to convert completely triglycerides and phospholipids into fatty acid methyl esters (FAMEs), the acid catalyst caused significant degradation of conjugated linoleic acid C18:2c9t11 at high temperature. Although a milder temperature can mitigate this negative impact, a long reaction time (2 h) is required to achieve full methylation. By contrast, despite being unable to methylate free fatty acids (FFA), the alkaline-catalysed transesterification yielded comparable results for all major FA due to the very low level of FFA in milk. The alkaline-catalysed methylation is benign for C18:2c9t11. We recommend here a simple one-step protocol based on 0.2 M methanolic KOH, a short reaction time (20 min) and a mild reaction temperature (50 °C) for milk FAME preparation. [ABSTRACT FROM AUTHOR]

Bovine milk contains 3–5% of fat, of which the dominant portion (about 98%) is in the form of triacylglycerols, whereas polar lipids such as glycerophospholipids and sphingolipids are minor components (0.5–1%) of milk fat. Milk fat is thought to contain several thousand lipid species, making it the most complex material in nature in terms of lipid composition. Significant progress has been made in the past two decades in the identification and quantification of lipid species of milk thanks to the advance in analytical tools especially high-resolution mass spectrometers (MS). Currently, milk lipids are characterized mainly in two ways, i.e. global fatty acid composition profiling by gas chromatography and lipid molecular species identification and quantification by liquid chromatography tandem MS; the former provides information related to the physicochemical properties and nutritive quality of milk fat, whereas the latter provides the detailed chemical structure of lipid species. Until now, only about 400 lipid species have been described in bovine milk, with many low-abundance species remaining to be discovered. The merits and limitations of various separation techniques and different MS methodologies applied to lipid structural elucidation and quantification are critically reviewed and the challenging problems to be solved in milk lipidomic analysis highlighted. [ABSTRACT FROM AUTHOR]

The aquatic plant Azolla became increasingly popular as bioenergy feedstock because of its high growth rate, production of biomass with high levels of biofuel-producing molecules and ability to grow on marginal lands. In this study, we analysed the contribution of all organs of Azolla to the total yield of lipids at vegetative and reproductive stages and in response to stress. Triacylglycerol-containing lipid droplets were detected in all (vegetative and reproductive) organs with the highest level in the male microsporocarps and microspores. As a result, significantly higher total yields of lipids were detected in Azolla filiculoides and Azolla pinnata at the reproductive stage. Starving changed the yield and composition of the fatty acid as a result of re-direction of carbon flow from fatty acid to anthocyanin pathways. The composition of lipids, in regard the length and degree of unsaturation of fatty acids, in Azolla meets most of the important requirements for biodiesel standards. The ability of Azolla to grow on wastewaters, along with their high productivity rate, makes it an attractive feedstock for the production of biofuels. [ABSTRACT FROM AUTHOR]

Seasonal change of milk composition could offer opportunities for dairy manufacturers. A systematic survey on seasonal variation of six classes of polar lipids was conducted with 19 Holstein cows over the entire milking season using liquid chromatography-mass spectrometry technique. This study revealed that most polar lipid classes were positively correlated with the total fat content, but negatively correlated with fat globule size. All polar lipid classes displayed a large cow-to-cow variation as well as seasonal variation. All of the six classes showed a gradual increase over the milking season with the highest concentration observed in May (autumn). However, the proportion of different polar lipid classes remained constant during the entire milking season. This finding suggests that the production of polar lipids is highly regulated in the mammary gland. The implication of such a seasonal variation of polar lipids in the nutritional and technological aspects of milk is discussed. [ABSTRACT FROM AUTHOR]

Using LC-LTQ-Orbitrap MS we were able to identify 10 major phosphatidylinositol (PI) species present in 32 infant formulas (IF) collected from Australia, Europe and the USA. Based on the species fingerprint, the 32 formulas can be classified into several distinct groups by PCA analysis; this grouping pattern reflects origin and the label information of the formulas. The total content of all PI species was determined by LC-Triple Quadrupole MS in negative MRM mode using external standard calibration. The content of PI showed large variation between formulas and was very high in certain cases, which is believed to be related to the use of soybean lecithin in these products. Our study indicates that the content and speciation of PIs have significant contribution to the total amount of inositol in all 32 products surveyed; this contribution may be important for the fine nutritional profile and biological functions of IF products. [ABSTRACT FROM AUTHOR]

• First adoption of Paterno-Buchi reaction in studying milk lipid fine structure. • Unsaturated fatty acids show a non-specific regio-distribution in phospholipids. • Regioisomers are widespread in milk phospholipid species. • Double-bond isomers of C18:1 and C18:2 are widely detected in milk phospholipids. Hundreds of phospholipid (PL) species with defined fatty acid (FA) composition have been identified previously in bovine milk using liquid chromatography tandem mass spectrometry (LC-MS/MS). Paterno-Buchi photochemical reaction coupled with LC-MS/MS was applied in this study to further unravel the regio-distribution and double bond (DB) locations of FAs. Using SPE-purified PLs and 2-acetylpyridine as the photochemical derivatization reagent, we were able to reveal the non-specific regio-distribution of unsaturated FAs and the widespread occurrence of regioisomers in milk PLs. Although Δ9 and Δ9,12 were found to be the predominant DB location(s) for C18:1 and C18:2 respectively, other DB positional isomers such as C18:1Δ11, C18:1Δ12 and C18:1Δ13 and C18:2Δ9,11 were widely detected in PL structures, implying that the minor isomers of C18:1 and C18:2 equally participate in the synthesis of PLs. Our study provides novel information on the fine structure of milk PLs and further underlines the complexity of milk lipid composition. [ABSTRACT FROM AUTHOR]

• Two thraustochytrids species were tested for nutritional potential. • The marine fungus was tested for nutritional potential. • Both species were tested for the ability to consume wastewater nutrients. • Produced biomolecules: PUFA, DHA, proteins, carbohydrates, squalene, and carotenoids. This paper represents a comprehensive study of two new thraustochytrids and a marine Rhodotorula red yeast isolated from Australian coastal waters for their abilities to be a potential renewable feedstock for the nutraceutical, food, fishery and bioenergy industries. Mixotrophic growth of these species was assessed in the presence of different carbon sources: glycerol, glucose, fructose, galactose, xylose, and sucrose, starch, cellulose, malt extract, and potato peels. Up to 14 g DW/L (4.6 gDW/L-day and 2.8 gDW/L-day) of biomass were produced by Aurantiochytrium and Thraustochytrium species, respectively. Thraustochytrids biomass contained up to 33% DW of lipids, rich in omega-3 polyunsaturated docosahexaenoic acid (C22:6, 124 mg/g DW); up to 10.2 mg/gDW of squalene and up to 61 μg/gDW of total carotenoids, composed of astaxanthin, canthaxanthin, echinenone, and β-carotene. Along with the accumulation of these added-value chemicals in biomass, thraustochytrid representatives showed the ability to secrete extracellular polysaccharide matrixes containing lipids and proteins. Rhodotorula sp lipids (26% DW) were enriched in palmitic acid (C16:0, 18 mg/gDW) and oleic acid (C18:1, 41 mg/gDW). Carotenoids (87 μg/gDW) were mainly represented by β-carotene (up to 54 μg/gDW). Efficient growth on organic and inorganic sources of carbon and nitrogen from natural and anthropogenic wastewater pollutants along with intracellular and extracellular production of valuable nutrients makes the production of valuable chemicals from isolated species economical and sustainable. [ABSTRACT FROM AUTHOR]

• Two new methods for fatty acid methylation without lipid extraction were validated. • Dried milk can be reliably used for in situ alkali-catalysed transesterification. • Acidic methylation of fresh milk is feasible with optimised reaction parameters. • The new methods are applicable to both homogenised and raw milk samples. Determination of the fatty acid (FA) profile of milk fat generally involves total lipid extraction from liquid milk, transesterification and GC analysis. The lipid extraction step is time consuming and often employs toxic solvents such as chloroform. Two alternative methods are presented here that skip the lipid extraction step and allow the determination of FA composition via direct transesterification of dried milk and liquid milk respectively. We have shown that dried milk can be used directly in alkaline-catalysed methylation, whereas direct transesterification of both dried milk and fresh milk is feasible with acidic methanol. Both methods generate similar results as compared to the classical two-step method (i.e. lipid extraction and FA methylation) when optimised methylation parameters (temperature, time, milk and reagent volume) are followed. By omitting the lipid extraction step, these simplified one-step methods offer a much higher throughput and a reduced cost in FA composition analysis of milk samples. [ABSTRACT FROM AUTHOR]

• Large-scale shaking table tests were carried out for a subway station structure. • The isolation mechanism of Mini-NRB installed in the structure were studied. • Real-time monitoring of structure deformation was realized. • Mini-NRB reduces the bending moment of column by 60%–80% and shear force by 90%. A series of shaking-table tests of a subway station structure with mini natural rubber bearings (Mini-NRBs) installed at column ends were carried out for near-field earthquake motions. By comparing the dynamic response of the structure model with or without Mini-NRB, the isolation mechanism and effectiveness of Mini-NRB on the station model were studied. It is found that the Mini-NRB has an obvious isolation effect on the column of the structure. After installing Mini-NRB, the lateral stiffness of the column decreases greatly, which reduces the bending moment and shear force at the column end by 60%–80% and about 90% respectively under near-field earthquake excitation. The test data, real-time monitoring pictures, and ultimate structural seismic damage all show that Mini-NRB shares most of the lateral deformation of the column, so that the column is no longer a vulnerable spot of the subway station structure. In addition, Mini-NRB reduces the high frequency component of the middle plate response, thus reducing the peak acceleration response of the middle plate by 3%–10%. However, the lateral deformation of the structure and the internal force of the sidewall will increase. The lateral deformation of the structure with Mini-NRB increases by 30%–50% and the bending moment at the end of the side wall increases by 5%–25%. [ABSTRACT FROM AUTHOR]

The practice of crime risk mapping, enabled by the utilization of geospatial big data such as street view images, has received significant research attention. However, in situations where available data is scarce, mapping models may suffer from underfitting and generate inaccurate spatial pattern estimations of crime risk. The covert nature of pickpocketing crimes results in limited observed areas relevant to such criminal events, leading to insufficient coverage of geospatial data. Moreover, the location of crime is also influenced by socio-economic characteristics that may introduce biases into crime risk estimates. These factors render it challenging for the model to capture a valid crime risk pattern, potentially yielding misleading conclusions. Therefore, effectively extracting crime risk with limited data remains a challenge, especially when relying on easily accessible, widespread, and unbiased geospatial data. To address this challenge, we propose a novel crime risk assessment framework based on deep anomaly detection techniques, assuming that urban landscape anomalies carry deep crime risk information. We take Shenzhen as the study area and map the distribution of pickpocketing risk using street view images, accurately revealing the spatial aggregation of pickpocketing crime risk. Our findings indicate that pickpocketing crime in China is caused by regional economic conditions, built environment factors, and human routine activities. This study provides valuable insights for policing and prevention strategies aimed at addressing pickpocketing crimes in large Chinese cities. By leveraging our proposed crime risk assessment framework, decision-makers can allocate resources more efficiently and develop targeted interventions to mitigate crime risks. • A deep learning-based model for mining pickpocketing crimes from street view images is proposed. • With the idea of anomaly detection, crime risk information can be extracted from a small number of street view images with crime labels. • The reliable parcel-level pickpocketing risk distribution was mapped in China's megacity. • Pickpocketing crime in China is multifactorial and spatially heterogeneous. • Pickpocketing crime risk is aggregated and affected by neighbourhood socioeconomic conditions and the built environment. [ABSTRACT FROM AUTHOR]

• A lightweight nonlinear response prediction model is established based on 1D-CNN. • The performance of 1D-CNN is excellent. • The randomness of ground motions and soil parameters are considered simultaneously. • The calculation cost of stochastic seismic response has been significantly reduced. • A comprehensive stochastic dynamic analysis is conducted using PDEM. The randomness of ground motions and soil properties has a significant impact on the seismic response of underground structures. The probability density evolution method (PDEM) is a powerful stochastic dynamic analysis method. By decoupling the physical space and probability space, any number of random excitation variables can be incorporated into the dynamic system, thereby accurately capturing the time-varying evolution of structural dynamic response. However, due to the expensive computational cost of nonlinear time history analysis (NLTHA) of underground structures, the application of the PDEM that requires many calculation samples is severely limited. In view of this, this paper proposes a lightweight stochastic seismic response analysis method for the subway station structure based on deep learning and PDEM. Firstly, mathematical models of stochastic ground motions and random soil shear wave velocity profiles are constructed. Two types of random excitations are coupled using the high-dimensional space optimization point selection method. The one-dimensional convolutional neural network (1D-CNN) is used as a proxy model to map the free field's nonlinear time-history response to the subway station structure's nonlinear time-history response. The computational cost of stochastic dynamics analysis has been significantly reduced. Subsequently, the predicted results are combined with PDEM to conduct a comprehensive analysis and evaluation of the subway station structure's seismic response and seismic performance. The research results indicate that the proposed 1D-CNN model has superior predictive performance, with a computational cost of approximately 92.5% less than the traditional process. The evolution of the subway station structure's inter-storey drift ratio (IDR) is mainly influenced by stochastic ground motions. However, under the combined random excitation, the peak value of IDR is larger and its occurrence time is earlier, so the establishment of earthquake evacuation plans should refer to this working condition. Both the randomness of soil properties and the randomness of ground motions need to be considered, otherwise, underground structures' seismic performance will be overestimated. This study provides new technologies and directions for seismic analysis and design of underground structures. [ABSTRACT FROM AUTHOR]

• A new seismic barrier for underground structures is proposed to control the Rayleigh waves. • The soil acceleration response is reduced within the frequency range of 0.5–5 Hz. • The maximum layer drift of the subway station is reduced by over 40 %. • The internal forces of structural components are reduced by 70 % on average. • A novel index is proposed to evaluate the performance of seismic barriers. This research introduces a novel seismic mitigation approach for civil engineering constructions, utilizing seismic metamaterials, and particularly studies its application to underground structures. This approach involves the implementation of a regional seismic barrier, designed in the form of piles periodically clamped to a concrete foundation. The efficacy of this seismic barrier is explored through comprehensive numerical simulations. A wave propagation study is conducted to investigate the attenuation efficiency for Rayleigh waves in the frequency domain. Besides, dynamic analysis is performed on a two-layer and three-span subway station subjected to actual seismic recordings. The results from the wave propagation study reveal a notable reduction in acceleration response within the frequency range of 0.5 Hz–5 Hz when employing the seismic barrier, in contrast to the free-field scenario. Dynamic analysis demonstrates that the implementation of the proposed seismic barrier leads to a significant decrease in both the maximum layer drift and the structural internal forces of the subway station. Moreover, the relative displacement of soil proves to be a pertinent metric for evaluating the seismic control efficacy of the proposed barrier for underground structures. [ABSTRACT FROM AUTHOR]

Phosphorus (P) is an essential nutrient controlling plant growth and development through the regulation of basic metabolic processes. Soil P deficiency is one of the major limiting factors for sustainable crop production worldwide. Previous studies have demonstrated that silicon (Si), as a beneficial element, promotes plant nutrition, growth, development, and responses to low P (LP) stress; however, the molecular mechanisms underlying Si-mediated LP tolerance remain largely unclear. Here, we found that LP + Si treatment increased the net photosynthetic rate and shoot fresh weight by 34.3%, and 121.3%, respectively compared with LP alone. RNA-sequencing and metabolomic analyses were subsequently performed with tomato plants grown under control and P depleted conditions with or without Si amendment. RNA-sequencing showed that Si supply alters not only the expression of genes involved in the metabolism of carbon (C), nitrogen (N), and P but also phosphorylation processes and metabolism of glutathione and reactive active oxygen in tomato roots. Si also affected the expression of genes encoding major transcription factors such as WRKY and MYB under LP stress. Moreover, a set of genes encoding the enzymes or regulators of organic acid (OA) metabolism or secretion were differentially expressed in Si-treated P deficient roots compared with those in LP stress alone. Furthermore, the metabolomic analysis showed that the levels of several OAs were significantly elevated in Si-treated P deficient roots. Taken together, these results indicate that exogenous Si increases the secretion of OAs by modulating C/N metabolism in LP-treated tomato roots and thereby improving plant growth under LP stress. • Silicon (Si) improved antioxidant defense and mitigated low phosphorus (LP) stress. • RNA-sequencing revealed regulation of GSH and ROS metabolism by Si under LP stress. • Si also altered the transcripts of major transcription factors such as WRKY and MYB. • Genes involved in organic acid (OA) metabolism were differentially modulated by Si. • Metabolomic analysis showed accumulation of OAs in Si-treated roots under LP stress. [ABSTRACT FROM AUTHOR]

• A novel seismic intensity measure for underground structures is proposed. • The seismic response characteristics of underground structures can be considered. • The rigidity degradation of the dynamic system can be considered. • The period range significantly affecting the seismic response for underground structures is obtained. The purpose of this study is to present a novel approach to constructing intensity measures (IMs) for underground structures using seismic response spectrums. The proposed IM takes the form of an integral of the product of the response spectrum and an arbitrary function that reflects the relative importance of each range of period to the seismic response of underground structures. To obtain the arbitrary function, an artificial neural network (ANN) technique is employed. To demonstrate the effectiveness of this method, we develop two different soil-subway station dynamic systems, referred to as Case I and Case II. Based on both cases, the probabilistic seismic demand model (PSDM) for the proposed IM and eight existing IMs are developed. The performance of the proposed IM is compared with that of the existing IMs in terms of their proficiency, practicality, and efficiency, as well as their ability to describe the probabilistic distribution of damage measure (DM). The results indicate that the proposed IM outperforms the existing IMs since it has the highest proficiency for both cases. Moreover, the fragility curves calculated using the proposed IM are more effective than those calculated using traditional IMs, with narrower uncertainty ranges, which can help reduce the uncertainty in evaluating seismic risk. Comparing the function solved by the ANN with the seismic response of subway stations under different periods of harmonic excitation, it can be found that the solved function and the seismic response reach their peak points at the same period. This finding suggests that the proposed IM can account for the interaction between the surrounding soil and underground structures, as well as the softening of soil layers during earthquakes, making it a suitable IM for underground structures. [ABSTRACT FROM AUTHOR]

Highlights • Endothall amine efficacy was greater when plants were exposed in moving water. • Endothall amine was less potent as it aged in water solutions. • Potency was generally reduced from 12 h after application. Abstract The amine formulation of endothall is a herbicide that may be applied to flowing irrigation canals to control submerged aquatic weeds and algae. We undertook a bioassay experiment to simulate the effects of water movement and increasing distance away from an application point on control of aquatic weeds. We exposed two submerged aquatic plants (Elodea canadensis and Vallisneria australis) to endothall amine solutions. This was done a) with solutions that were aged for 0, 12, 24 and 48 h prior to plant exposure, to simulate the effect of distance downstream of the application point, and b) in three hydrodynamic environments: quiescent, low-flow and high-flow. Endothall amine was less potent on both species as the solution aged, such that potency was generally reduced from 12 h after application. The concentration of endothall acid did not decrease in the exposure tanks during the experiment, suggesting that there is a change of the endothall amine molecule as it ages in water, which reduces the herbicide's potency. Endothall amine efficacy was greater for both species when plants were exposed in moving water compared to quiescent water. We propose that the increased efficacy in moving water is caused by a reduction in the thickness of the aqueous diffusive boundary layer in the hydrodynamic environment, thus increasing the rate of endothall amine diffusion into the plant tissue. This information can be used to improve management of submersed aquatic weeds with endothall amine and to understand its potential impact on non-target aquatic plants as herbicide-treated water moves away from the area of application. [ABSTRACT FROM AUTHOR]

Several novel orange emission supramolecular phosphorescent polymers (SPPs) with different counterions of PF 6 −, Br− and BIm 4 - have been developed for polymer light-emitting diodes. The formation of SPPs, utilizing efficient non-bonding assembly of dibenzo-24-crown-8-tethered iridium complex and dibenzylammonium-functionalized fluorene-dibenzothiophene-S,S-dioxide cooligomer, are monitored by 1H NMR and viscosity measurement. The influences of different counterions on the optical, thermal and electroluminescent (EL) properties of the resulting SPPs, as well as the supramolecular assembly behavior are investigated in detail. These SPPs display high glass transition temperatures of ca. 100 °C. The single-emissive-layer PLED with SPP-PF 6 exhibits the highest device efficiency of 12.32 cd A−1 with the Commission Internationale de L'Eclairage (CIE) coordinates of (0.57, 0.43). More importantly, owing to "spacer" effect of the large BIm 4 - counterion, the device based on SPP-BIm 4 show very low efficiency roll-off. Supramolecular phosphorescent polymers (SPPs) with different counterions of PF 6 −, Br− and BIm 4 - have been developed for orange polymer light-emitting diodes, which exhibit good thermal stability and excellent electroluminescent properties. Image 1 • SPPs with different counterions of PF 6 −, Br− and BIm 4 - are obtained. • All the SPPs display orange light-emitting with a CIE coordinates of (0.57, 0.43). • The PLEDs based on SPP-PF 6 exhibited a highest LE of 12.32 cd A−1. • Due to "spacer" effect, the device with SPP-BIm 4 shows very low efficiency roll-off. [ABSTRACT FROM AUTHOR]