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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.

Previous studies have shown that methamphetamine (METH) can induce complex adaptive changes in the reward system in the brain, including the changes in the content of neurotransmitters in the signal transduction pathway. However, how the changes of various neurotransmitters in relevant brain reward circuits contribute to METH-induced conditioned place preference (CPP) remains unclear.In this study, first, we designed an animal model of METH-induced CPP. Then we used liquid chromatography-mass spectrometry (LC-MS) to simultaneously determine the contents of various neurotransmitters - dopamine (DA), norepinephrine (NE), 5-hydroxytryptamine (5-HT), 5-hydroxyindole acetic acid (5-HIAA), glutamic acid (Glu) and glutamine (Gln) - in different brain regions of the prefrontal cortex (PFc), nucleus accumbens (NAc), caudate-putamen (CPu) and hippocampus (Hip), which are believed to be relevant to the drug's reward effect.The results of the behavioral experiment suggested that 1.0 mg/kg METH could induce obvious CPP in mice. The results about various neurotransmitters showed that: DA significantly increased in NAc in the METH group; Glu increased significantly in the METH group in PFc and NAc and Gln increased significantly in the METH group in PFc.These results suggested that the neurotransmitters of DA, Glu and Gln may work together and play important roles in METH-induced CPP in relevant brain reward circuits, especially in PFc and NAc. These findings therefore could help to advance the comprehensive understanding of the neurochemic and psychopharmacologic properties of METH in reward effect, which is important for future improvements in the treatment of drug addiction.

Hydrogen sulfide (HThe HIn HThiosulfate is a reliable biomarker of acute H

Cell, enzyme, and tissue activity in living organisms are closely related to intracellular pH. Detecting the changes of intracellular pH is important to understanding the physiological and pathological changes in the process of crucial cell metabolism. A pH probe (HTBI) based on hemicyanine was synthesized. The probe solution displayed a marked colour change from yellow to amaranth with the pH increase from neutral to basic; simultaneously, the emission spectra showed a significant red shift. The probe exhibited a ratiometric fluorescence emission (F

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.

A protocol was developed, via a data-dependent high-resolution tandem mass spectrometry (ddHRMS/MS), to detect six biomarkers of dichlorvos in its metabolites and blood adducts of butyrylcholinesterase and albumin without using standard synthetic peptides. Firstly, the adducts of dimethoxy phosphonate (DMP-BChE) and the aged adducts of methoxy phosphonate (MxP-BChE) were isoloated by immunomagnetic separation (IMS), and then digested to DMP-nonapeptide and MxP-nonapeptide by pepsin. The dichlorvos and its metabolites (Trimethyl phosphate, Dimethyl phosphate) were analyzed in the supernatant of IMS treatment after protein precipitation. The precipitate was digested by pronase to phosphorylated tyrosine (DMP-Tyr), which were quantified by ultra performance liquid chromatography-quadrupole/electrostatic field orbitrap mass spectrometry (UPLC-MS). The linearity of detector response of all biomarkers was studied in their respective ranges, and the correlation coefficients (R

Levo-tetrahydropalmatine (L-THP) is the main active ingredient of Corydalis and Stephania and is widely used for its sedative, analgesic, and neuroleptic effects. Though L-THP is an antagonist of dopamine receptors and has been proven to be effective in treating drug addiction, its effect on fentanyl-induced reward learning still remains unclear. This experiment was designed to investigate the effects of L-THP on fentanyl-induced rewarding behavior through conditioned place preference (CPP) in mice. Western blot assays were used to dissect the accompanying changes in the phosphorylation of extracellular signal-regulated kinase (ERK) and cAMP response element binding protein (CREB) in related brain regions, including the hippocampus (Hip), caudate putamen (CPu), prefrontal cortex (PFC), and nucleus accumbens (NAc), which may mediate the effects of L-THP on fentanyl-induced CPP. The results revealed that fentanyl could induce CPP in mice at doses of 0.025 mg/kg, 0.05 mg/kg, 0.1 mg/kg, and 0.2 mg/kg, and L-THP could attenuate the acquisition of fentany-induced CPP at a dose of 10.0 mg/kg. The levels of p-ERK and p-CREB of the saline+fentanyl group (0.05 mg/kg) increased significantly in the Hip, NAc, and PFC compared to the saline+saline group. Furthermore, L-THP (10.0 mg/kg) co-administered with fentanyl during conditioning prevented the enhanced phosphorylation of ERK and CREB in the Hip, NAc, and PFC. Our research revealed that L-THP could suppress the rewarding properties of fentanyl-induced CPP, the inhibitory effect may be related to the suppression of ERK and CREB phosphorylation in the Hip, NAc, and PFC of mice. Thus, L-THP may have therapeutic potential for fentanyl addiction.

Based on the specific interaction of Ag+ and cytosine-cytosine (C-C) base mismatch and using berberine (Ber) as the fluorescent probe and Exonuclease I (Exo I) as the background fluorescence reducing tool, a label-free Exo I-assisted fluorescence aptamer sensing platform was established for the detection of silver ions with high sensitivity and selectivity. Exo I reduced the fluorescence background of the Ber/Ag+-aptamer complex to a level similar to that of Ber itself in the absence of Ag+. After introducing Ag+ into the sensing system, it induces the aptamer rich in base C to form C-Ag+-C i-motif structure which are resistant to degradation mediated by Exo I. The concentration of Ber, Ag+-aptamer, Exo I and the temperature and reaction time for Exo I were all optimized. Under the optimal experimental conditions, the detection limit of Ag+ was 4.4 nM and the linear range was from 0.0059 μM to 235.48 μM with a coefficient of determination (R2) > 0.99. Moreover, the proposed strategy had been successfully applied to the detection of Ag+ in tap water and human serum with a good recovery ranging from 88.4% to 106.9%.

Organophosphorus pesticides (OP

Driving under the influence of diazepam is increasing in China. The pharmacokinetics of diazepam and its metabolites, especially the glucuronide metabolites, are helpful in the identification of diazepam use by drivers. This study aimed to investigate the pharmacokinetics of diazepam and its metabolites (nordazepam, oxazepam, oxazepam glucuronide and temazepam glucuronide) in the blood of Chinese people, and to provide basic data for identifying diazepam use and estimating the time of last diazepam ingestion. A total of 28 participants (14 men, 14 women) were recruited and each person received 5 mg diazepam orally. Whole blood was collected at 0 h (pre-dose), and 1 h, 2 h, 4 h, 8 h, 12 h, and 24 h, and at 2 days, 3 days, 6 days, 12 days, and 15 days post-dose. Analytes of interest were extracted via solid-phase extraction and analyzed by a liquid chromatography tandem mass spectrometry method operated in a positive multiple response monitoring mode. Pharmacokinetic parameters were analyzed by a pharmacokinetic software DAS according to the non-compartment model. The time of last diazepam use was estimated using the concentration ratios of diazepam to metabolites and metabolites to metabolites from controlled drug administration studies. The respective time of maximum concentration, the maximum concentration and the elimination half-life of diazepam were 1.04 ± 1.00 h, 87.37 ± 31.92 ng/mL and 129.07 ± 75.00 h; of nordazepam were 133.14 ± 109.63 h, 3.80 ± 1.75 ng/mL, and 229.73 ± 236.83 h; of oxazepam were 100.29 ± 87.16 h, 1.62 ± 2.64 ng/mL, and 382.86 ± 324.58 h; of temazepam glucuronide were 44.43 ± 55.41 h, 2.08 ± 0.88 ng/mL, and 130.53 ± 72.11 h; and of oxazepam glucuronide were 66.86 ± 56.33 h, 1.10 ± 0.41 ng/mL, and 240.66 ± 170.12 h. A good correlation model was obtained from the concentration ratio of diazepam to nordazepam and the time of diazepam use, and the prediction errors were less than 20%. This study provides a sensitive method to identify diazepam ingestion by monitoring diazepam and its metabolites including glucuronides, as well as to infer the time following oral consumption.

Male Sprague-Dawley rats (n = 18) were randomly divided into three groups: a saline group (20 mL/kg by gavage), a ketamine (KET) group (100 mg/kg by gavage), and a KET (the same routes and doses) combined with levo-tetrahydropalmatine (l-THP; 40 mg/kg by gavage) group (n = 6). Blood samples were acquired at different time points after drug administration. A simple and sensitive ultraperformance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method was established to determine the concentrations of KET and its metabolite, norketamine (NK), in rat plasma. Chromatographic separation was achieved using a BEH C18 column (2.1 mm × 50 mm, 1.7 μm) with chlorpheniramine maleate (Chlor-Trimeton) as an internal standard (IS). The initial mobile phase consisted of acetonitrile–water with 0.1% methanoic acid (80 : 20, v/v). The multiple reaction monitoring (MRM) modes of m/z 238.1→m/z 179.1 for KET, m/z 224.1→m/z 207.1 for NK, and m/z 275→m/z 230 for Chlor-Trimeton (IS) were utilized to conduct a quantitative analysis. Calibration curves of KET and NK in rat plasma demonstrated good linearity in the range of 2.5–500 ng/mL (r > 0.9994), and the lower limit of quantification (LLOQ) was 2.5 ng/mL for both. Moreover, the intra- and interday precision relative standard deviation (RSD) of KET and NK were less than 4.31% and 6.53%, respectively. The accuracies (relative error) of KET and NK were below -1.41% and -6.07%, respectively. The extraction recoveries of KET and NK were more than 81.23 ± 3.45% and 80.42 ± 4.57%, respectively. This sensitive, rapid, and selective UPLC-MS/MS method was successfully applied to study the pharmacokinetic effects of l-THP on KET after gastric gavage. The results demonstrated that l-THP could increase the bioavailability of KET and promote the metabolism of KET. The results showed that l-THP has pharmacokinetics effects on KET in rat plasma.

Male Sprague-Dawley rats (n=18) were randomly divided into three groups: a saline group (20 mL/kg by gavage), a ketamine (KET) group (100 mg/kg by gavage), and a KET (the same routes and doses) combined with levo-tetrahydropalmatine (l-THP; 40 mg/kg by gavage) group (n=6). Blood samples were acquired at different time points after drug administration. A simple and sensitive ultraperformance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method was established to determine the concentrations of KET and its metabolite, norketamine (NK), in rat plasma. Chromatographic separation was achieved using a BEH C18 column (2.1 mm×50 mm, 1.7 μm) with chlorpheniramine maleate (Chlor-Trimeton) as an internal standard (IS). The initial mobile phase consisted of acetonitrile–water with 0.1% methanoic acid (80 : 20, v/v). The multiple reaction monitoring (MRM) modes of m/z 238.1→m/z 179.1 for KET, m/z 224.1→m/z 207.1 for NK, and m/z 275→m/z 230 for Chlor-Trimeton (IS) were utilized to conduct a quantitative analysis. Calibration curves of KET and NK in rat plasma demonstrated good linearity in the range of 2.5–500 ng/mL (r>0.9994), and the lower limit of quantification (LLOQ) was 2.5 ng/mL for both. Moreover, the intra- and interday precision relative standard deviation (RSD) of KET and NK were less than 4.31% and 6.53%, respectively. The accuracies (relative error) of KET and NK were below -1.41% and -6.07%, respectively. The extraction recoveries of KET and NK were more than 81.23±3.45% and 80.42±4.57%, respectively. This sensitive, rapid, and selective UPLC-MS/MS method was successfully applied to study the pharmacokinetic effects of l-THP on KET after gastric gavage. The results demonstrated that l-THP could increase the bioavailability of KET and promote the metabolism of KET. The results showed that l-THP has pharmacokinetics effects on KET in rat plasma.

A novel ratiometric emission NIR-fluorescence probe N,N-dimethyl-4-((1E, 3E)-4-(3,3-dimethyl-3H-indol-2-yl)buta-1,3-dienyl)benzenamine, namely, DIDBA, is facilely synthesized on the basis of ethylene bridging of indole derivatives and 4-(dimethylamino) cinnamaldehyde. The probe exhibits a remarkable NIR ratiometric fluorescence emission (F618nm/F697nm) characteristic with pKa 4.5, and the linear response over the pH range of 3.5–5.2. DIDBA also displays favorable features include large Stokes shift of 200 nm under acidic conditions, high sensitivity, good selectivity, fine photostability and reversibility. The probe has low cytotoxicity and excellent cell membrane permeability, and is applied successfully to visualize intracellular pH fluctuations in live cells without influence of autofluorescence and native cellular species in biological systems.

Drug degradation as a consequence of putrefactive bacterial activity is a well-known factor that affects the identification and quantitation of certain substances of forensic interest. Current knowledge on putrefaction-mediated degradation of drugs is, however, significantly lacking. This study aimed to investigate the degradation of 4-methylmethcathinone (4-MMC or mephedrone) and to detect its degradation products in putrefied biological matrices containing 4-MMC. The bacteria species Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae and Proteus vulgaris were grown in brain-heart infusion broth, spiked with 4-MMC and incubated at 37°C for 24 h. Postmortem human blood and fresh porcine liver macerate were also left to putrefy in sample tubes at room temperature for 1 week. Structural elucidation was based on modern spectroscopic analyses including the use of high-resolution mass spectrometry and nuclear magnetic resonance spectroscopy. All four putrefactive bacteria were capable of degrading 4-MMC extensively under the experimental conditions explored. Of particular interest was the discovery of a novel degradation product common to all four bacterial species, which was assigned as 2-hydroxy-1-(4-methylphenyl)propan-1-one (HMP) based on the spectroscopic data. This degradation product was detectable in both postmortem human blood and porcine liver samples. The stability of the identified degradation products, especially HMP, should be further investigated to assess their validity of serving as marker analytes for monitoring 4-MMC in postmortem toxicology.

Screen content videos (SCVs) are becoming popular in many applications. Compared with natural content videos (NCVs), the SCVs have different characteristics. Therefore, the screen content coding (SCC) based on HEVC adopts some new coding tools (intra block copy and palette mode etc.) to improve coding efficiency, but these tools increase the computational complexity as well. In this paper, we propose to predict the CU partition of the SCVs by a convolutional neural network (CNN) which is trained by the large-scale database that we firstly established for screen content coding. The proposed approach is implemented in SCC reference software SCM-6.1. Experimental results show that our proposed approach can save 53.2% encoding time with 2.67% BD-rate increase on average in All Intra (AI) configurations.

Diazepam abuse is widespread all over the word, leading to an increasing number of forensic cases such as suicide, drug-driving and robbery, but relevant studies are limited regarding the extraction of diazepam and its metabolites in oral fluid. This study aimed to investigate the pharmacokinetics of diazepam and its metabolites in oral fluid after a single oral dose in healthy volunteers. There was a total of 28 volunteers, and each ingested 5 mg diazepam orally, then ~2 mL oral fluid were collected from each participant at post-consumption time-points of prior (zero), 1, 2, 4, 8, 12, 24 h and 2, 3, 6, 12 and 15 days, respectively. All samples were extracted with solid-phase extraction and analyzed with high-performance liquid chromatography-tandem mass spectrometry method, and diazepam and nordazepam were detected in the oral fluid of volunteers. Pharmacokinetics of diazepam in oral fluid conformed to a two-compartment model, and k01_HL, k12_HL, k10_HL were 0.7 ± 1.1, 31.4 ± 68.5, 12.1 ± 11.6 h, respectively, nordazepam conformed to an one-compartment model, and k01_HL, k10_HL were 41.5 ± 44.8, 282.3 ± 365.5 h, respectively. Both diazepam and nordazepam could be detected continuously for 15 days, although there were individual differences, and the results regarding diazepam detecting in oral fluid will be of much help in forensic science and drug screening filed.

Overexploitation of rare earth elements (REEs) has caused serious desertification and environmental pollution. The ecological restoration of mining areas has attracted increasing attention in China. Soil microbiota is important for successful ecological remediation of abandoned mine land. In this study, soil samples were collected from a restored REE mine site, and the bacterial community composition and diversity were assessed by Illumina high-throughput sequencing targeting the V3-V4 region of the 16S rRNA gene. Microbiota significantly developed in the remediated land. A total of 663,781 effective 16S rRNA gene sequences were obtained, which were classified into 28 bacterial phyla and 3 archaeal phyla. The dominant phyla across all samples (>5% of total effective sequences) were Proteobacteria, Acidobacteria and Firmicutes. Bacterial diversity indices (OTU number, Shannon index and Chao1 index) of the restored soils were higher than those of the tailings and even surpassed those in the unmined site. Redundancy analysis indicated that soil nutrients (soil organic carbon, available phosphorus and total nitrogen) were the dominant factors, followed by soil pH, affecting bacterial community structure. In general, these results suggested that soil amendment and phytoremediation effectively improved the soil environment of the abandoned mine site, which also increased our understanding of the correlation between microbial variation and soil properties in restored REE mine soils.

Endophytic fungi from Paeonia lactiflora Pallas, which is mainly distributed in China, were characterized and screened to identify those capable of producing paeoniflorin. A total of 101 isolates obtained from the roots, stems and leaves of P. lactiflora were grouped into 16 fungal taxa based on morphological traits and internal transcribed spacers sequences, indicating that endophytic fungi of P. lactiflora are abundant and diverse. The dominant endophytic fungi were Aspergillus, Alternaria and Penicillium. More fungi were recovered from leaves than from roots and stems. The similarity index was highest between the stems and leaves (0.733), followed by the roots and leaves (0.615) and the stems and roots (0.563). Analyses of the fermentation extracts of 22 endophytic fungi by high-performance liquid chromatography and mass spectrometry revealed that three strains (R12, Alternaria tenuissima; S4, Aspergillus flavus; and R17 Penicillium commune) were able to produce paeoniflorin. Among the paeoniflorin-producing fungi, the yield of paeoniflorin from A. flavus S4 was 342.4 μg/L, and this strain could be used as a candidate for the industrial production of paeoniflorin.

In the coming decades, exploitation of plant growth promoting bacteria (PGPB) will be a major trend in sustainable agriculture. Except for rhizobacteria, the bacteria inhabiting the non-rhizosphere could be considered the supplementary microbial source to exploit PGPB. Rare earth tailings soil (RETS) has caused a serious threat to sustainable agriculture due to excessive aluminum (Al) toxicity under acidic condition (pH

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.

As a safety-security field, the transportation field always encourages and embraces advanced intelligent technologies to reduce risks. Recently, automated driving has received extensive attention from researchers and industries, as it is expected to improve the flow of traffic, to significantly reduce drivers’ errors and thusly increase safety. Though many efforts have put on automated driving, many challenges remain in achieving fully autonomous, resulting in partially automated driving. The role of drivers in a partially automated car is monitoring and taking over driving in specific conditions, which is significantly different from the manual cars. The novel role of drivers induces new human factors issues and challenges to maintain traffic safety. This study tries to investigate these human factors issues involved in the human and automated driving interactions and to propose a framework of electrical engineering and automation-based intelligent technology application to mitigate risks. Specifically, trust, attention, situational awareness, and alarm fatigue were identified as significant human factors issues in automated driving. An electrical engineering and automation-based intelligent framework for monitoring cognitive states and generate warnings was proposed.