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In this paper, a rapid and sensitive multiplex flow-through immunoaffinity chromatography test (FTIACT) was developed for the on-site screening of 14 sulfonamide and 13 quinolone residues in milk. The developed FTIACT method combines the purification, preconcentration and immunochemical detection of multiple antibiotics on the sepharose gel test layers. The use of liposome-encapsulated quantum dots (LQDs) with the FTIACT method exhibited the best results, with limits of detection (LODs) of 1 and 0.5 ng/mL for the sulfonamides (SAs) and quinolones (QNs), respectively, through qualitative analysis (visual detection by the naked eye). In order to achieve low detection limit, the color intensity of the images were converted into relative optical density values to enable a quantitative evaluation. Quantitative analysis of the samples enabled the detection of SAs (0.13 ng/mL) and QNs (0.062 ng/mL) in spiked milk samples. The FTIACT described in this work shows promise as a multiplex immunoassay for the qualitative and quantitative screening of multiple chemical residues in milk. [ABSTRACT FROM AUTHOR]

Highlights: [•] The efficacy and safety of LNG-IUSs use in women with symptomatic uterine leiomyoma. [•] LNG-IUSs could decrease uterine volume and endometrial thickness. [•] LNG-IUSs could reduce menstrual blood loss. [•] LNG-IUS expulsion was related to leiomyoma size. [•] LNG-IUSs have no adverse effects on the ovarian function except for ovarian cysts. [Copyright &y& Elsevier]

Abstract: Fumonisin B1 (FB1) is a mycotoxin, mainly produced by Fusarium fungi and present in food and feed. It causes harmful effects on human and animal health. Therefore, it is necessary to develop sensitive and reliable screening methods. In this study, a highly sensitive monoclonal antibody (MAb) against FB1, clone 2D7, was produced, and the 50% inhibition concentration (IC50) of the MAb was 2.2 ng/mL in buffer. The MAb showed high cross-reactivity with fumonisin B2 (FB2), and negligible cross-reactivity with other mycotoxins. A sensitive indirect competitive enzyme-linked immunosorbent assay (icELISA) based on this MAb was developed for the determination of FB1 in maize. In spiked samples (100, 200 and 500 μg/kg), the average recoveries ranged from 78 ± 11 to 107 ± 4%, and the coefficient of variation ranged from 3 to 15%. The limit of detection of the icELISA was 5.4 μg/kg. This method was compared to liquid chromatography tandem mass spectrometry (LC–MS/MS) using naturally contaminated samples, and the correlation coefficient was above 0.82. These results show the reliability of the icELISA method for the determination of FB1 in maize. [Copyright &y& Elsevier]

Abstract: A sensitive and specific enzyme-linked immunosorbent assay (ELISA) for the detection of 1-amino-hydantoin (AHD) is described. AHD, the marker residue for nitrofurantoin, is a tissue bound toxic metabolite. To monitor the illegal use of nitrofurantoin, a monoclonal antibody-based ELISA method was developed to detect AHD residue in animal tissues. The highly specific antibody against AHD was prepared by monoclonal antibody technology. The antibody exhibited negligible cross reactivity with other nitrofurans, their metabolites and derivatives, and 50% inhibitory concentration was 0.68 μg/L. The limit of detection in four kinds of animal tissues were all below 0.2 μg/kg and recoveries ranged from 75% to 116.7% for fortified samples at levels of 0.2–5 μg/kg with coefficient of variation values below 15%. Analysis of natural contaminated samples by the ELISA method gave similar results to those of the liquid chromatography-tandem mass spectrometry method. These results indicate the ELISA method is suitable for the detection of AHD residue in animal tissues. [Copyright &y& Elsevier]

Abstract: Here, we present a case in which the result of a maternity test was obscured due to two false indirect exclusions that occurred in two out of 15 genetic loci through the use of the AmpFlSTR Identifiler PCR Amplification kit (Applied Biosystems, Foster City, CA). The Identifiler kit failed to amplify allele 11 of the D5S818 system on the child and failed to capture the existence of allele 13 on the FGA system on both mother and child. The situation was remedied through use of the PowerPlex 16 PCR Amplification Kit (Promega, Madison, WI) which used different primers with a different allele range than that of the Identifiler kit. Maternity was confirmed through sequencing and it was found that the failure of the Identifiler kit to amplify allele 11 on the D5S818 system was the result of an incompatibility to the primer-binding site due to a mutation that changed a guanine (G) into a thymine (T) 55 base pairs (bp) downstream of the repeat. The inability of the Identifiler kit to pick up allele 13 of the FGA system was due to the out-of-range location of the allele. Indirect exclusions can be misleading if they are not fully investigated since allele range as well as primer-binding affinity are two confounders that must be addressed to ensure accuracy of the test results. [Copyright &y& Elsevier]

Online ride-hailing as an innovative travel mode becomes increasingly popular in cities around the world. To improve the efficiency of dispatching system of ride-hailing, many ride-hailing demand prediction models based on deep learning architecture have been proposed to reduce the gross travel distance between drivers and passengers. However, in most of these prediction models, only the error metrics are used for performance evaluation. There is scarce evidence on how much the demand prediction model reduces the unnecessary travel distance in reality. In this study, a multi-scenario-based method is proposed to evaluate technical potentials of the ride-hailing demand prediction model in ride-hailing dispatching system simulation. The ride-hailing dispatching is simulated in three scenarios: traditional dispatching system, prediction model-based dispatching system, and perfect prediction model-based dispatching system. One-month data of Didi Express service provided by Didi Chuxing GAIA Initiative in Chengdu is employed to support the simulation. Two terms, empty distance and relative performance, are introduced as the criteria of prediction model performance measurement. Simulation results reveal that the total empty distance reduced 1,164 km per day by using the prediction model compared with the traditional dispatching system. The relative performance is only 58.9% compared with the perfect prediction model-based dispatching system. [ABSTRACT FROM AUTHOR]

Abstract A reliable ultra-high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method was developed for the simultaneous identification and quantification of 22 β-agonist residues in swine muscle and liver tissues. A special focus was given to sample the pretreatment procedures and was crucial for an accurate and reliable analytical method. With regard to the high complexity of food matrices, the extraction solvent, time, and temperature, as well as clean-up cartridges, were optimized to improve the extraction efficiency and reduce matrix effects. The UHPLC-MS/MS method was further validated by determining the linearity (R2 ≥ 0.9900), sensitivity (limit of detection varying from 0.05 μg/kg to 0.8 μg/kg, limit of quantitation ranging from 0.2 μg/kg to 2.5 μg/kg), recovery (ranging from 76.4 to 111.7%) and precision (≤22.9%) in swine muscle and liver tissues. The UHPLC-MS/MS method was proven to be suitable for both screening and the confirmatory determination of 22 β-agonist residues in swine muscle and liver tissues. [ABSTRACT FROM AUTHOR]

In this study, the N -doped carbon dots were continuously synthesized by a facile microfluidic strategy at 90 °C, and their quantum yields reached 19.2%. The characteristics of the obtained carbon dots could be real-time monitored in order to synthesize carbon dots with specific properties. By incorporating the carbon dots into a well-established enzymatic cascade amplification system, an inner filter effect-based fluorescence immunoassay was set up for ultrasensitive detection of cefquinome residues in milk samples. The developed fluorescence immunoassay provided a low detection limit of 0.78 ng/mL, which satisfied the maximum residue limit set by authorities. The fluorescence immunoassay had an 50% inhibition concentration of 0.19 ng/mL against cefquinome and showed a good linear relationship from 0.013 ng/mL to 1.52 ng/mL. While, the average recovery values ranged from 77.8% to 107.8% in spiked milk samples, with relative standard deviations ranging from 6.8% to 10.9%. Compared with conventional methods, the microfluidic chip was more flexible on carbon dots synthesis and the developed fluorescence immunoassay was more sensitive and eco-friendlier for ultra-trace cefquinome residue analysis. [Display omitted] [ABSTRACT FROM AUTHOR]

Fluorescence resonance energy transfer (FRET) between fluorescein isothiocyanate (FITC) and gold nanoparticles (Au NPs) is introduced in the lateral flow strip to detect cancer biomarker CEA with the color and fluorescence dual-readout. Anti-CEA monoclonal antibody coated Au NPs were on the conjugate pad and FITC labelled antibody (FITC-Ab) for CEA was coated on the test line. All the reagents were general in the lateral flow strip or commercially available and no new materials or technique were involved, which make our proposal a more universal method and easier to operate. With the addition of CEA on the sample pad, anti-CEA monoclonal antibody coated Au NPs-CEA-FITC-Ab complex formed on the test line, leading to a megascopic red line and simultaneous quenched fluorescence of FITC via FRET. The visual limit of detection (LOD) through distinguishing red color change was 10 ng/mL and the LOD by differentiating fluorescence intensity was 0.1 ng/mL, which was two orders of magnitude lower than that without considering fluorescence in the strip. And the linear range changed from 10–80 ng/mL to 5–80 ng/mL with the analysis of fluorescence change. Meanwhile, the feasibility of our method applied in real clinical samples was also confirmed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel aggregation-induced emission luminogens encoded microspheres were synthesized. • An anti-microcystin-LR antibody conjugated Sepharose gel column was prepared. • A fast and sensitive immunoaffinity chromatographic method was developed for microcystin-LR. Despite decades of efforts, we are faced with the daunting task of on-site ultratrace environmental toxins detecting, especially the microcystins caused by water bloom. In this work, a novel fluorescent microsphere-based flow-through immunoaffinity chromatographic assay has been designed for detecting ultratrace microcystin-LR in water and aquatic products. The aggregation-induced emission luminogens were encapsulated into fluorescent microspheres to ensure microcystin-LR quantitation with a whole analytical time of less than 30 min. Furthermore, the colorimetric images were captured and quantitatively analyzed, which offered a limit of detection at 0.217 pg/mL and a limit of quantitation at 0.362 pg/mL in water and aquatic muscle samples. The developed immunoassays provide average recovery ranging from 79.1 % to 95.7 %, with relative standard deviations less than 13.4 %. Thus, the validated flow-through immunoaffinity chromatographic assay is an easy-to-use alternative for on-site screening of microcystin-LR in water and aquatic samples at picogram levels. [ABSTRACT FROM AUTHOR]

In this study, new clindamycin (CLIN) artificial antigens were prepared and used to produce broad-specificity monoclonal antibodies. Based on the as-produced mAbs, a heterologous ELISA was developed to detect CLIN and lincomycin (LIN) residues in edible animal tissues. The IC 50 values of the developed assay were 0.3 ng/mL (CLIN) and 1.2 ng/mL (LIN) in buffer, respectively. The detection limits were estimated to be 1.8 μg/kg (CLIN) and 6.8 μg/kg (LIN) in bovine, chicken, porcine and fish muscles. In the spike and recovery tests, the mean recovery rate ranged from 76% to 112% at different spiked levels, and the intra −/inter-assay coefficients of variation were in the range of 7.1% to 13.2%. This method was verified using LC − MS/MS with a correlation coefficient > 0.97. The developed ELISA is therefore well suited for simultaneous determination of CLIN and LIN residues in bovine, chicken, porcine and fish muscles. [ABSTRACT FROM AUTHOR]

A sensitive and specific monoclonal antibody against clindamycin (CLIN) was produced and used to develop an immuno-affinity test column (IATC) assay for on-site screening of CLIN residues in milk. The qualitative limit of detection of the IATC assay, estimated as 1.0 μg L −1 by visual detection, was sufficient to measure maximum residue levels for lincosamide antibiotics in milk. The quantitative IATC assay resulted in a lower detection limit (0.11 μg L −1 ) by evaluating the colour intensity of the test layers, which was approximately 9 times greater sensitivity than visual detection. During the spike and recovery test, the average recoveries ranged from 76% to 114% at different spiked levels, and the intra-/interday coefficients of variation were in the range 9.6–16.7%. The detection time was shortened to 20 min, whereas the sensitivity was comparable with a traditional ELISA. The IATC assay shows promise for on-site screening of CLIN residues in milk. [ABSTRACT FROM AUTHOR]

A multi-class multi-residue analysis method for determination of veterinary drugs, pesticides and mycotoxins in dairy products by liquid chromatography–tandem mass spectrometry (LC–MS/MS) has been established. These 17 classes, a total of 40 kinds of target compounds were chosen because their administration to food-producing animals is banned or regulated in China and may be potentially abused or misused. Samples were extracted with acetonitrile–ethyl acetate–acetic acid (49.5 + 49.5 + 1, v/v/v). Most of lipids in the extract were removed by low-temperature cleanup, prior to solid phase extraction on HLB cartridges. The quantification and confirmation of the 40 analytes were performed by LC–MS/MS with electro-spray ionization (ESI) interface in multiple reaction monitoring (MRM) mode. The limits of detection (LODs) and limits of quantification (LOQs) were 0.006–0.3 μg/kg and 0.02–1.0 μg/kg, respectively. The spiked recoveries in milk, yogurt, milk powder and cheese samples were from 67.3% to 106.9%. The repeatability and the within-laboratory reproducibility were less than 12.7% and 13.9%. Applying this method, our results revealed the presences of chloramphenicol, cimeterol, and flunixin at the concentration of 0.027–0.452 μg/kg in some samples. [ABSTRACT FROM AUTHOR]

Objective: To conduct a meta-analysis of the studies assessing the effects of mifepristone on the uterus, uterine leiomyoma, and leiomyoma-related symptoms in premenopausal women. Design: Meta-analysis. Setting: Centers for reproductive care. Patient(s): Premenopausal women who suffered from leiomyoma. Intervention(s): We identified all of the studies published before December 2012 that compared the status of patients with leiomyoma before and after treatment with mifepristone. Main Outcome Measure(s): Leiomyoma-related symptoms, uterine or leiomyoma volume, changes in endometrial thickness. Result(s): A meta-analytic technique was used to study 11 randomized controlled trials involving 780 women with symptomatic uterine leiomyomas. The subjects received 2.5–25 mg/d of mifepristone for 3–6 months. Mifepristone could effectively reduce uterine and leiomyoma volume and alleviate leiomyoma symptoms, including hypermenorrhea, the mean menstrual blood loss, pelvic pain, pelvic pressure, anemia, and dysmenorrhea. There was no significant difference in the rate of atypical endometrial hyperplasia between the mifepristone treatment group and the placebo group. Conclusion(s): Mifepristone significantly reduced uterine and leiomyoma volume and alleviated leiomyoma-related symptoms. We recommend 2.5 mg of mifepristone administered daily for 3 or 6 months as the optimum clinical treatment for leiomyoma. There is insufficient evidence that mifepristone treatment led to atypical endometrial hyperplasia. [Copyright &y& Elsevier]

[Display omitted] • We synthesized carbon dots with quantum yields reaching 97.1%. • An inner filter effect immunosensor was setup for aflatoxin M 1 residue analysis. • Our immunosensor detection limit was 0.0186 ng/mL for aflatoxin M 1 in milk. • This immunosensor format is flexible for other chemical residue analysis. Here, a facile hydrothermal method was used to synthesize highly photoluminescent N -doped carbon dots, and the quantum yields reached 97.1%. Then, a label-free immunosensor based on the inner filter effect of carbon dots was developed for ultrasensitive detection of aflatoxin M 1 residues in milk. The detection limit was 0.0186 ng/mL (equivalents to 18.10 ng/kg), which satisfied the most stringent maximum tolerable limit value of 25 ng/kg. Besides, the immunosensor showed a good linear relationship from 0.003 ng/mL to 0.81 ng/mL, and the average recoveries ranged from 79.6% to 112.5% for spiked milk samples, with relative standard deviations ranging from 6.7% to 13.3%. Compared with other immunoassays, the inner filter effect-based immunosensor incorporating fluorescent detection into conventional enzymatic cascade amplification systems and could be a reliable on-site screening method for aflatoxin M 1 residue analysis. [ABSTRACT FROM AUTHOR]

The on-road braking emission has been proved by former studies to account for a considerable part of on-road transportation. To improve cleaner air in urban area, the spatio-temporal analysis on emission performance of on-road braking is necessary as a guideline for decision-making. In this paper, we propose a framework for analysis on the particle matter emission of on-road vehicle braking events on an urban scale. We used massive vehicle trajectories in Tokyo area with short time interval as the database for analysis. From the result, we found that within the in the study area, the average driving distance during braking takes up about 20.60% of total driving distance. The average quantity of PM10 emission from braking for each driving trajectory is 14.09 mg and the one from exhaust emission is 35.36 mg. The emission from braking can averagely occupy 39.85% of exhaust emission. What's more, in our finding, the braking emission from heavy duty vehicle is 2.33 times of light duty vehicle. From the spatial distribution of PM10 braking emission, we found that braking emission usually happened in the city center and popular crowded areas due to the large traffic volume, as well as the main trunk roads of capital expressway or highway. We also found a different spatial pattern between the light duty vehicle and heavy-duty vehicle. In temporal change, we found that rapid peaks during the rush hour on weekday and contrastive stabilization on weekend. We believe our finding can provide a clearer pattern and understanding on the emission behavior of on-road vehicle braking. Image 1 • Proposing a framework to for analysis on the particle matter emission of on-road vehicle braking events on an urban scale. • Proposing a method to detect and mine emission from braking behaviors from GPS trajectory data of vehicle travelling. • Over twenty million historical GPS points of individual vehicle in Tokyo area are employed for analysis. • We found that emission from braking can occupy 39.85% of exhaust emission and HDV emits 2.33 times of LDV. [ABSTRACT FROM AUTHOR]

Low tumor mutational burden and absence of T cells within the tumor sites are typical characteristics of "cold immune tumors" that paralyzes the immune system. The strategy of reversing "cold tumors" to "hot tumors" infiltrated high degree of T cells in order to activate anti-tumor immunity has attracted lots of attentions. Herein, immunogenic core–shell Au@Se NPs is fabricated by gold-selenium coordination bond to realize nanoparticles-mediated local photothermal-triggered immunotherapy. As expected, incorporation of gold nanostars (AuNSs) with improved photothermal stability and conversion efficiency promotes the disintegration and transformation of selenium nanoparticles (SeNPs), thus leading to enhanced cancer cells apoptosis by producing higher hyperthermia. Moreover, the results of in vivo experiments demonstrate that the synergy between SeNPs-mediated chemotherapy and AuNSs-induced photothermal therapy not only generated a localized antitumor-immune response with excellent cancer killing effect under the presence of tumor-associated antigens, but also effectively reprogrammed the tumor associated macrophages (TAMs) from M2 to M1 phenotype with tumoricidal activity to devour distant tumors. Without a doubt, this study not only provides a potent strategy to reverse the immunosuppressive tumor microenvironment, but also offers a new insight for potential clinical application in tumor immunotherapy. The present study provides demonstration of rational design of immunogenic nanotherapeutics Au@Se NPs for PTT-triggered immunotherapy involving reprogramming immunosuppression and activating systemic antitumor responses, which offers a new insight for potential clinical application in tumor immunotherapy. Image 1 [ABSTRACT FROM AUTHOR]

In recent years, Internet-supported non-dock bicycle-sharing service had emerged and gradually become warmly applauded by the public. In the non-dock bicycle-sharing system planning, the definition of coverage area and the division of sub service areas are highly essential and fundamental, which get little attention in the existing studies. In this paper, we propose a market-oriented methodology for non-dock bicycle-sharing system planning. Firstly, the potential demand of bicycle-sharing use is identified using mobile phone data. Then, a link network is constructed to represent the spatial distribution of potential demand. The algorithm of community detection is applied to the link network to discover the densely connected nodes in the area and define the division of sub service areas. Finally, the potential patterns of bicycle-sharing use, the spatial distribution of the potential demand, and the potential emission reduction are analysed based on the resulting division of sub service areas. The proposed method is tested using a data set of approximately 34 million GPS trajectories obtained in Tokyo. The area of Tokyo is subdivided into 21 sub service areas. Suggestions for bicycle management, infrastructure development, and the bicycle-sharing system planning are given regarding sub service areas with different properties. The potential emission reduction for the introduction of bicycle-sharing system is calculated in the area of Tokyo. Image 1 • A data set of 34 million trajectories is adopted to develop an integrated method. • A method of sub-area division for the bicycle-sharing system is proposed. • Travel pattern of potential bicycle-sharing behavior is described and analyzed. • Potential emission reduction of promoting bicycle-sharing is analyzed. [ABSTRACT FROM AUTHOR]