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Abstract Ketamine has recently become an anesthetic drug used in human and veterinary clinical medicine for illicit abuse worldwide, but the detection of illicit abuse and inference of time intervals following ketamine abuse are challenging issues in forensic toxicological investigations. Here, we developed methods to estimate time intervals since ketamine use is based on significant metabolite changes in rat serum over time after a single intraperitoneal injection of ketamine, and global metabolomics was quantified by ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF–MS). Thirty-five rats were treated with saline (control) or ketamine at 3 doses (30, 60, and 90 mg/kg), and the serum was collected at 21 time points (0 h to 29 d). Time-dependent rather than dose-dependent features were observed. Thirty-nine potential biomarkers were identified, including ketamine and its metabolites, lipids, serotonin and other molecules, which were used for building a random forest model to estimate time intervals up to 29 days after ketamine treatment. The accuracy of the model was 85.37% in the cross-validation set and 58.33% in the validation set. This study provides further understanding of the time-dependent changes in metabolites induced by ketamine abuse.

Abstract A gas chromatography-mass spectrometry (GC–MS) method for the determination of difenidol hydrochloride in biological specimens has been developed. The method exhibited excellent recovery (> 90%) and precision (RSD

Abstract The increase in car ownership has brought convenience to people's lives, but it has also led to a sharp increase in pedestrian–vehicle conflicts. Such conflicts can be avoided by braking when pedestrians in front of the car are detected. However, frequent braking reduces driving comfort and travel efficiency. Considering that pedestrian–vehicle conflicts always occur when pedestrians cross the road, this study proposes a multi‐factor fusion network (MFFN) to anticipate pedestrians' crossing intentions. MFFN contains a dual‐channel action recognition sub‐network to robustly identify pedestrians' actions by adaptively fusing pedestrians' skeleton and representation characteristics. Afterward, object‐level and semantic‐level perception of traffic scenes are realised by a hierarchical graph attention network and a lightweight semantic segmentation method, respectively. These hierarchical environmental contexts can provide critical clues for identifying pedestrians' crossing intentions. Then, a self‐attention mechanism is used to integrate various factors and produce intention identification results. The proposed MFFN is evaluated on public datasets PIE and JAAD. Experimental results show that the proposed method can accurately and reliably identify pedestrian crossing intentions. The accuracy, F1 score, AUC, and precision indicators on JAAD/PIE datasets are 0.912/0.876, 0.813/0.806, 0.896/0.889, and 0.802/0.788, respectively.

Abstract In recent years, the cases of tramadol intoxication have become more frequent in many countries. However, most of the previous studies have been based on cases of tramadol intoxication, and the detailed information on the differences between postmortem distribution and diffusion of tramadol remains unclear. To investigate this issue systematically, we established a postmortem distribution model and two postmortem diffusion models. Then, gas chromatography-mass spectrometry (GC/MS) was used to measure the concentrations of tramadol in various biological specimens of fluids and tissues. In postmortem distribution, the results showed an uneven distribution of tramadol in various biological specimens, and the concentrations of tramadol in urine were significantly higher than those in other fluids. In postmortem diffusion, the results showed a dosage-dependent increase of tramadol concentration in most specimens; at all time points from 0.25 to 6 h after postmortem administration, the concentrations of tramadol in fluids were not significantly different from those in tissues, and the concentrations of tramadol in urine were lower than those in both tissues and other fluids in most time points. We recommend a quantitative examination of the specimens of both fluids and tissues to provide more evidence for the forensic identification, and the realization that there is a correlation between the concentrations of fluids and tissues is important for determining antemortem and postmortem administration of tramadol. This information can serve as ancillary data in inferring the contribution of a drug to death in cases of suspected tramadol poisoning.

Blueberry is a high-quality fruit tree with significant nutritional and economic value, but the intricate mechanism of sugar accumulation in its fruit remains unclear. In this study, the ripe fruits of blueberry cultivars ‘Anna’ and ‘Misty’ were utilized as experimental materials, and physiological and multi-omics methodologies were applied to analyze the regulatory mechanisms of the difference in sugar content between them. The results demonstrated that the ‘Anna’ fruit was smaller and had less hardness than the ‘Misty’ fruit, as well as higher sugar content, antioxidant capability, and lower active substance content. A total of 7067 differentially expressed genes (DEGs) (3674 up-regulated and 3393 down-regulated) and 140 differentially abundant metabolites (DAMs) (82 up-regulated and 58 down-regulated) were identified between the fruits of the two cultivars. According to KEGG analysis, DEGs were primarily abundant in phenylpropanoid synthesis and hormone signal transduction pathways, whereas DAMs were primarily enriched in ascorbate and aldarate metabolism, phenylpropanoid biosynthesis, and the pentose phosphate pathway. A combined multi-omics study showed that 116 DEGs and 3 DAMs in starch and sucrose metabolism (48 DEGs and 1 DAM), glycolysis and gluconeogenesis (54 DEGs and 1 DAM), and the pentose phosphate pathway (14 DEGs and 1 DAM) were significantly enriched. These findings suggest that blueberries predominantly increase sugar accumulation by activating carbon metabolism network pathways. Moreover, we identified critical transcription factors linked to the sugar response. This study presents new understandings regarding the molecular mechanisms underlying blueberry sugar accumulation and will be helpful in improving blueberry fruit quality through breeding.

Abstract The determination of length of time from the last drinking is critical for cases like drunk driving, sexual assault victims, and also postmortem suspected poisoning cases. The study was aimed to established a method of estimating the time of last drinking through the pharmacokinetic study of conjugation metabolites of alcohol in blood after a single oral dose. Twenty-six volunteers (14 males) consumed alcohol with food at a fixed dose of 0.72 g/kg after fasting for 12 h. Five milliliters of blood were collected 120 h after the start of drinking, and all samples were analyzed with headspace-gas chromatography and high-performance liquid chromatography–tandem mass spectrometry. The time point of last drinking was estimated through the relationship between the concentration ratio of ethyl glucuronide to ethyl sulphate and the length of time after drinking. Pharmacokinetic parameters were analyzed by a pharmacokinetic software DAS according to the non-compartment model. A good correlation model was obtained from the relationship between concentration ratio of ethyl glucuronide to ethyl sulphate in blood and the time of alcohol use, and the margin of error was mostly lower than 10%. The time of maximum concentration, maximum concentration, and elimination half-life of ethyl glucuronide in blood were 4.12 ± 1.07 h, 0.31 ± 0.11 mg/L and 2.56 ± 0.89 h; the time of maximum concentration, maximum concentration, and elimination half-life of ethyl sulphate in blood were 3.02 ± 0.70 h, 0.17 ± 0.04 mg/L, and 2.04 ± 0.76 h. The study established a potential method to estimate the length of time after a moderate oral dose, and provided pharmacokinetic parameters of ethyl glucuronide and ethyl sulphate in Chinese population.

Accurate and fast phase locking is the primary condition for flexible DC transmission to realize reliable control. When the power grid is unbalanced or contains high-order harmonics, the traditional second order generalized integrator (SOGI) itself has the defect of strong dependence on the input signal frequency. Therefore, this paper proposes an improved phase-locked loops (PLL), which introduces moving average filter into the SOGI structure to filter out higher harmonics. The improved SOGI-PLL is simulated and analyzed under grid voltage unbalance and high harmonics. The results show that the improved SOGI-PLL has well grid adaptability.

To study the optimal form of nitrogen (N) application and to determine the best harvest date for blackberries, different N fertilizers were applied during the critical growth period of blackberry plants. The results showed that NH4+–N significantly improved the appearance of blackberry fruits, including their size, firmness, and color, and promoted the accumulation of soluble solids, sugars, anthocyanin, ellagic acid, and vitamin C (VC), while fruit treated with NO3−–N accumulated more flavonoids and organic acids and had improved antioxidant capacity. In addition, the fruit size, firmness, and color brightness decreased with the harvest period. While the contents of sugars, anthocyanin, ellagic acid, flavonoids, and VC were higher in the early harvests and then decreased as the season progressed, the total antioxidant capacity and DPPH radical scavenging capacity increased. In all, application of NH4+–N is recommended, as it is more beneficial to fruit appearance, taste, and nutritional quality. Harvests in the early stage help to obtain a good fruit appearance, while harvests in the middle and later stages are more beneficial to fruit taste and quality. This study may help growers to determine the best fertilization scheme for blackberries and choose the appropriate harvest time according to their needs.

Different light wavelengths display diverse effects on fruit quality formation and anthocyanin biosynthesis. Blueberry is a kind of fruit rich in anthocyanin with important economic and nutritional values. This study explored the effects of different light wavelengths (white (W), red (R), blue (B) and yellow (Y)) on fruit quality and gene expression of anthocyanin biosynthesis in blueberry. We found that the B and W treatments attained the maximum values of fruit width, fruit height and fruit weight in blueberry fruits. The R treatment attained the maximum activities of superoxide dismutase (SOD) and peroxidase (POD), and the Y treatment displayed the maximum contents of ascorbic acid (AsA), glutathione (GSH) and total phenol in fruits, thus improving blueberry-fruit antioxidant capacity. Interestingly, there were differences in the solidity–acid ratio of fruit under different light-wavelength treatments. Moreover, blue light could significantly improve the expression levels of anthocyanin biosynthesis genes and anthocyanin content in fruits. Correlation and principal component analysis showed that total acid content and antioxidant enzymes were significantly negatively correlated with anthocyanin content in blueberry fruits. These results provide new insights for the application of light wavelength to improve blueberry fruit quality and anthocyanin content.

Blackberries are an emerging third-generation fruit that are popular in Europe, and specific nitrogen (N) supply is an important factor affecting their growth and development. To study the optimal N fertilizer for blackberry seedlings, no N (CK), nitrate (NO3−)–N, ammonium (NH4+)–N and urea were applied to one-year-old ‘Ningzhi 4’ blackberry plants at a key growth period (from May to August) to explore the effects of different N forms on the physiological characteristics. Correlation and principal component analysis were used to determine the relationships between various indexes. Ammonium (NH4+) or urea-fed plants had a better growth state, showed a greater plant height, biomass, SPAD values and enhanced antioxidant enzyme activities and photosynthesis. In addition, NH4+ was beneficial to the accumulation of sugars and amino acids in leaves and roots, and promoted the transport of auxin and cytokinin to leaves. NO3− significantly inhibited root growth and increased the contents of active oxygen, malondialdehyde and antioxidants in roots. Correlation and principal component analysis showed that growth and dry matter accumulation were closely related to the antioxidant system, photosynthetic characteristics, amino acids and hormone content. Our study provides a new idea for N regulation mechanism of blackberry and proposes a scientific fertilization strategy.

DNA self-assembled fluorescent nanoprobes have been developed for bio-imaging owing to their high resistance to enzyme degradation and great cellular uptake capacity. In this work, we designed a new Y-shaped DNA fluorescent nanoprobe (YFNP) with aggregation-induced emission (AIE) characteristic for microRNA imaging in living cells. With the modification of the AIE dye, the constructed YFNP had a relatively low background fluorescence. However, the YFNP could emit a strong fluorescence due to the generation of microRNA-triggered AIE effect in the presence of target microRNA. Based on the proposed target-triggered emission enhancement strategy, microRNA-21 was detected sensitively and specifically with a detection limit of 122.8 pM. The designed YFNP showed higher bio-stability and cell uptake than the single-stranded DNA fluorescent probe, which has been successfully applied for microRNA imaging in living cells. More importantly, the microRNA-triggered dendrimer structure could be formed after the recognition of target microRNA, achieving a reliable microRNA imaging with a high spatiotemporal resolution. We expect that the proposed YFNP will become a promising candidate for bio-sensing and bio-imaging.

The use of combined wind and wave energy harvesting devices (CWWHDs) is an effective way to synergistically capture offshore wind and wave energy. However, the form of combined energy harvesting and coupled simulation techniques limit the development of CWWHDs. This paper classifies the existing CWWHDs based on wave energy converters and offshore wind turbines, summarizes the theoretical background and implementation forms of the numerical simulation of CWWHDs, and focuses on the technical details of wind-wave coupling and multi-body coupling simulation, which fills the gap in the research of the wind-wave coupling and multi-body coupling numerical simulation of CWWHDs. Finally, the current research focus and development direction of CWWHDs and their numerical simulation technology are summarized to provide a reference for the future development and application of CWWHDs and numerical simulation technology.

With improving living standards, traditional blueberry planting modes cannot meet commercial demands, and blueberry cultivation with soilless substrate has become a popular solution in the blueberry industry. In this study, different soilless substrate treatments were found to markedly influence fruit appearance and intrinsic quality. The fruit in the 50:50 peat/pine bark (v/v) (FPB) treatment group had the maximum single fruit weight, largest vertical diameter, and brightest color, as well as the highest 1,1-diphenyl-2-picrylhydrazyl (DPPH) value, solid-acid ratio and anthocyanin content. The fruit in the 50:50 pine bark/rice husk (v/v) (FBR) treatment group had the highest total phenol and flavonoid levels, largest drip loss value, and lowest total pectin content and firmness value. Metabolomic analysis showed that flavonoid, carbohydrate, and carbohydrate conjugate, and amino acid, peptide, and analog levels were significantly different between groups. Fruit in the FPB group had the highest sucrose, D-fructose 1,6-bisphosphate, salidroside, tectorigenin, naringenin chalcone, trifolirhizin, and galangin contents. The increase in the relative expression of phenylalanine (Phe) promoted the synthesis of fruit polyphenols in the FBR group. Our results provide new insights into the effects of different substrates on the quality of blueberries and a reference for the soilless substrate cultivation of blueberries.

Wake effects commonly exist in offshore wind farms, which will cause a 10–20% reduction of whole power production as well as a 5–15% increase of fatigue loading on the wind turbine main structures. Obviously wake interaction between floating offshore wind turbine (FOWT) is more complicated, and needs careful assessment which is a prerequisite for active wake control (AWC). The primary objective of the present research is to investigate in detail how the wake inflow condition, streamwise spacing, turbulence intensity, and wind shear influence the power performance, platform motion dynamic and structural loading of FOWT. FAST.Farm, developed by the National Renewable Energy Laboratory (NREL), was used for simulating two tandem FOWTs in different conditions. Comparisons were made between FOWTs in different conditions on power performance and platform motion dynamic, which were presented through both time and frequency domain analysis. Damage equivalent loads change in FOWTs interference under typical working conditions were discussed and summarized. Half wake inflow would pose many challenges to the downstream FOWT. These research studies can be incorporated into further offshore wind farm wake models, providing applicable AWC strategies to reduce wake interference effects for higher energy production and for the longer life of FOWT.

The objective of the study was to compare the concentration of lidocaine in different body fluids/tissues after subarachnoid space and intravenous administrations of a lethal dose of lidocaine. Totally 18 dogs were used in the experiment. Six dogs were given subarachnoid anesthesia, another were given an intravenous injection of a dose of 75 mg/kg weight of lidocaine hydrochloride in 5 min and the last 6 dogs were used as the blank control dogs and given a subarachnoid space injection or a femoral artery injection of the same volume of sodium chloride. As soon as its vital signs disappeared, each dog was dissected and the specimen, such as brain, cerebrospinal fluid (CSF) in lateral ventricle, CSF in subarachnoid space, spinal cord (cervical spinal cord, thoracic spinal cord, lumbar spinal cord, and waist spinal cord), heart, lung, liver, spleen, kidney, bile, urine, heart blood, peripheral blood, muscle in injection location, and muscle in no injection location, were collected for analysis of lidocaine immediately. Analysis was performed with gas chromatography-mass spectrometry (GC-MS). From the maximum to the minimum, the order of lidocaine concentration detected in the subarachnoid space-administered dogs was as follows: CSF in subarachnoid space, waist spinal cord, thoracic spinal cord, CSF in lateral ventricle, lumbar spinal cord, cervical spinal cord, lung, kidney, muscle in injection location, heart, brain, spleen, heart blood, liver, peripheral blood, bile, muscle in no injection location, and urine. The order of lidocaine concentration detected in the intravenously administered dogs was as followed: Kidney, heart, lung, spleen, brain, liver, peripheral blood, bile, heart blood, cervical spinal cord, thoracic spinal cord, muscle in injection location, lumbar spinal cord, muscle in no injection location, CSF in subarachnoid space, urine, and CSF in lateral ventricle. The maximum concentration of lidocaine was detected in the subarachnoid space CSF of subarachnoid space-administered dead dogs, while in intravenously injected dead dogs, the maximum concentration of lidocaine was detected in the kidney. Our study provides some useful data for the forensic identification of epidural anesthesia accidents to decide the way the lidocaine enters the body.

Soil bacteria are important drivers of biogeochemical cycles and participate in many nutrient transformations in the soil. Meanwhile, bacterial diversity and community composition are related to soil physic-chemical properties and vegetation factors. However, how the soil and vegetation factors affect the diversity and community composition of bacteria is poorly understood, especially for bacteria associated with evergreen and deciduous trees in subtropical forest ecosystems. In the present paper, the microbial communities of rhizospheric soils associated with different types of trees were analyzed by Illumina MiSeq sequencing the V3-V4 region of the 16S rRNA gene. A total of 121,219 effective 16S rRNA gene sequences were obtained, which were classified into 29 bacterial phyla and 2 archaeal phyla. The dominant phyla across all samples (>5% of good-quality sequences in each sample) were Proteobacteria, Acidobacteria, Firmicutes and Bacteroidetes. The bacterial community composition and diversity were largely affected by both soil pH and tree species. The soil pH was the key factor influencing bacterial diversity, with lower pH associated with less diverse communities. Meanwhile, the contents of NO3- were higher in evergreen tree soils than those associated with deciduous trees, while less NH4+ than those associated with deciduous trees, leading to a lower pH and indirectly influencing the diversity and composition of the bacteria. The co-occurrence patterns were assessed by network analysis. A total of 415 pairs of significant and robust correlations (co-occurrence and negative) were identified from 89 genera. Sixteen hubs of co-occurrence patterns, mainly under the phyla Acidobacteria, Proteobacteria, Firmicutes and Bacteroidetes, may play important roles in sustaining the stability of the rhizospheric microbial communities. In general, our results suggested that local environmental conditions and soil pH were important in shaping the bacterial community of the Taihu Lake zone in east China.

The gummosis disease is caused by Botryosphaeria dothidea (Moug. ex. Fr) Ces. et de Not., and it is one of the most important diseases of stone fruits worldwide. The use of biocontrol as an alternative approach to synthetic chemical fungicides has aroused general concern about how to control plant diseases that are caused by phytopathogens. The aim of this study is to isolate Bacillus strains from raw honeys with the capacity to inhibit B. dothidea and to explore the mechanisms by which they could be used in the biocontrol of peach gummosis. Bacillus amyloliquefaciens SYBC H47 was isolated and identified on the basis of its physiological and biochemical characteristics and its 16S rRNA and gyrB gene sequences. The cell suspension and the cell-free supernatant of its culture showed significant antifungal activity against Aspergillus niger, Mucor racemosus, Fusarium oxysporum, Penicillium citrinum, and Candida albicans by agar-diffusion assays. The primary antifungal substances were bacillomycin L, fengycin, and surfactin, which were analyzed by HPLC LC/ESI-MS/MS. Bacillomycin L showed the best inhibitory effect against conidial germination of B. dothidea, followed by fengycin and surfactin. Surfactin had limited effects on mycelial growth, contrary to those of bacillomycin L and fengycin. However, a mixture of the three lipopeptides had a synergistic effect that disrupted the structure of the conidia and mycelia. In order to reduce the production cost, the use of waste frying peanut oil and soy oil as the sole carbon source increased the lipopeptide yield levels by approximately 17% (2.42 g/L) and 110% (4.35 g/L), respectively. In a field trial, the decreases in the infected gummosis rate (IGR) and the disease severity index (DSI) through cell suspension treatments were 20% and 57.5% (in 2014), respectively, and 40% and 57.5% (in 2015), respectively, in comparison with the control. In conclusion, B. amyloliquefaciens SYBC H47 could inhibit the germination of conidia and the growth of mycelia from B. dothidea; therefore, this strain behaves as a potential biocontrol agent against the gummosis disease.