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Abstract: Combinatorial maps are widely used in image representation and processing, however map matching problems have not been extensively researched. This paper addresses the problem of inexact matching between labeled combinatorial maps. First, the concept of edit distance is extended to combinatorial maps, and then used to define mapping between combinatorial maps as a sequence of edit operations that transforms one map into another. Subsequently, an optimal approach based on A * algorithm and an approximate approach based on Greedy algorithm are proposed to compute the distance between combinatorial maps. Experimental results show that the proposed inexact map matching approach produces richer search results than the exact map matching technique by tolerating small difference between maps. The proposed approach performs better in practice than the previous approach based on maximum common submap which cannot be directly used for comparing labels on the maps. [Copyright &y& Elsevier]

• TAP, FF and FFA was monitored and determined by UPLC-FLD. • A new method is used to detect TAP, FF and FFA residues in poultry meat and pork. • ASE was investigated as a rapid and automated approach. • The method provides reliable accuracy for determining TAP, FF and FFA. A method of accelerated solvent extraction coupled with ultra-performance liquid chromatography-fluorescence detection (ASE-UPLC-FLD) for the simultaneous detection of thiamphenicol, florfenicol and florfenicol amine residues in poultry meats (chicken muscle, duck muscle and goose muscle) and pork was developed and optimized. Samples were extracted with ASE using ethyl acetate:aqueous ammonia (98:2,V/V) as the extractant and purified with n-hexane saturated with ethyl acetate. Then, the samples were analyzed by UPLC-FLD. The excitation wavelength and emission wavelength of the fluorescence detector were 233 nm and 284 nm, respectively. The parameters of the optimized method were validated according to the requirements of the European Union and the Food and Drug Administration. The recoveries of the three analytes from poultry meats and pork at the limit of quantification (LOQ), 0.5 MRL (maximum residue limit), 1.0 MRL and 2.0 MRL were 80.80–98.35%, the relative standard deviations (RSDs) were less than 4.63%, and the intraday and interday RSDs were 2.22–5.54% and 2.42–6.08%, respectively. The limits of detection (LODs) and the LOQs were 1.0–4.2 μg/kg and 3.0–11.4 μg/kg, respectively. The new method was successfully applied for the quantitative determination of thiamphenicol, florfenicol and florfenicol amine residues in 40 poultry meat and pork samples from local supermarkets. [ABSTRACT FROM AUTHOR]

A novel confirmatory analysis method to simultaneously extract, clean-up and detect dinitolmide and its metabolite (3-amino-2-methyl-5-nitrobenzamide, 3-ANOT) in chicken tissues using accelerated solvent extraction (ASE) with a neutral alumina solid-phase extraction (SPE) column coupled with gas chromatography-tandem mass spectrometry (ASE-SPE-GC–MS/MS) was established. GC–MS/MS was performed using a VF-5ht capillary column with helium as the carrier gas, temperature programming, and an inlet temperature of 340 °C. The experimental method was carried out in the electron ionization mode; the full scan mode was used for qualitative analysis, and selective reaction monitoring, combined with an external standard method was used for quantitation. Under the optimized conditions, at the addition levels of the limits of quantitation (LOQs), 0.5 MRL (maximum residue limit), 1 MRL and 2 MRL, the average recoveries of dinitolmide and 3-ANOT in chicken tissues were 81.96–94.31%, and the relative standard deviations (RSDs) were 1.72–5.37%. The limits of detection (LODs) (S/N ≥ 3) of dinitolmide and 3-ANOT in chicken tissues were 0.8–2.5 μg/kg, and the LOQs (S/N ≥ 10) were 2.7–8.0 μg/kg. The method validation parameters met the Chinese Ministry of Agriculture, European Union and United States Food and Drug Administration veterinary drug residue detection requirements. [ABSTRACT FROM AUTHOR]

• Simultaneous determination of tetracycline, oxytetracycline, doxycycline, enrofloxacin and ciprofloxacin residues in chicken muscles by UPLC-FLD. • The fluorescence detector output signals were processed by dual-channel detection. • The sample pretreatment process was optimized. A sensitive, rapid and efficient ultra-performance liquid chromatography-fluorescence detection (UPLC-FLD) method was established for detecting tetracycline (TC), oxytetracycline (OTC), doxycycline (DOX), enrofloxacin (ENR) and ciprofloxacin (CIP) residues in chicken muscle. Moreover, the fluorescence detector output signals were processed by dual-channel detection. The samples were extracted with a mixture of acetonitrile and 0.1 M citric acid containing 100 mM magnesium chloride (1:1, V/V, adjusted the pH to 5.0 with ammonia) using liquid-liquid extraction (LLE) and purified by Oasis PRiME hydrophilic-lipophilic balance (HLB) solid-phase extraction (SPE) cartridges (60 mg/3 mL). The target compounds were separated on an ACQUITY UPLC BEH C 18 (100 mm × 2.1 mm, 1.7 μm) chromatographic column using a mobile phase composed of acetonitrile and 0.1 M malonic acid solution containing 50 mM magnesium chloride hexahydrate, and the pH was adjusted to 5.5 by adding ammonia. The limits of detection (LODs) and limits of quantification (LOQs) of the five target compounds in chicken muscle were 0.1–13.1 μg/kg and 0.4–39.4 μg/kg, respectively. The recoveries of the five target compounds in chicken muscles were above 87.33 % when the spiked concentrations were at the LOQ, 0.5 maximum residue limit (MRL), 1.0 MRL and 2.0 MRL. The intraday relative standard deviations (RSDs) were less than 4.91 %, and the interday RSDs were less than 5.13 %. Ultimately, this novel detection method was successfully applied to the quantitative analysis of TC, OTC, DOX, ENR and CIP in 20 commercial chicken samples from local supermarkets. [ABSTRACT FROM AUTHOR]