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Fireworks play a vital role in festive celebrations and entertainment. These fireworks industries are administered by the Petroleum and Explosives Safety Organisation (PESO), Nagpur, Government of India. Even though PESO prescribed the standard composition for various fireworks products, concerns persist regarding the potential deviation from these standards, particularly in the pursuit of increased noise levels to attract consumers. This change in the burning and reactive properties of chemicals could potentially lead to accidents and environmental pollution. The current work investigated the combustion characteristics of two unknown market flash powder samples and a PESO standard sample. The samples were openly ignited in a controlled atmosphere, and video recordings of the resulting chemical flames were analyzed to determine fire area, flame intensity, and motion magnitude. The residues were also collected for EDAX and SEM analysis. Fire pixels from video frames are segmented to create a comprehensive database detailing flame area and motion magnitude under different circumstances. From the flame area profile, motion magnitude and SEM/EDAX analysis, it is found that PESO standard sample combustion is better than the unknown flash powder combustion. • Burning flame of fireworks chemicals captured by CCD. • Flame area and volume had been found by Digital Image Processing. • Residue analysis was carried out. • Through flame analysis and residue analysis, fuel properties had been explored. [ABSTRACT FROM AUTHOR]

Simplified and effective pretreatment methods combined with high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) for the determination of four aminoglycoside antibiotic pesticides kasugamycin, validamycin, streptomycin sulfate and zhongshengmycin in high starchy content matrix (rice), high water and high acidic content matrix (citrus) and high water content matrix (melon) were established. Single-factor and central composite design (CCD) experiments were employed to optimize the pretreatment conditions, resulting in the optimal factor combinations and achieving scientifically accurate outcomes. Validation results proved satisfactory, with all four target compounds exhibiting correlation coefficients (r) exceeding 0.99 within the linear range in three matrices. The recoveries were 81.5–102.2 %, and both inter-day and intra-day relative standard deviations (RSDs) were below 10.7 %. The limits of detection (LODs) were 0.1–4.0 μg/kg, with limits of quantitation (LOQs) consistently at 50 μg/kg. Furthermore, the methods were applied to potato, grape, and cucumber matrices to further validate their applicability. [Display omitted] • Simultaneous detection of four aminoglycoside pesticides in plant agri-products. • The pretreatment methods were simpler and more effective than traditional SPE. • Optimization of pretreatment conditions by CCD, ensuring reliability of results. • Good recovery, sensitivity and repeatability were obtained. [ABSTRACT FROM AUTHOR]

[Display omitted] • A SPE extraction approach was optimized for milk and infant formula-based products purification. • A LC − MS/MS method to detect the 9 fasciolicides and 3 metabolites was developed. • Method linearity, quantification, precision, and accuracy were evaluated. • 15 milk and 30 infant formula samples were tested. A new sensitive method of liquid chromatography–tandem mass spectrometry (LC–MS/MS) analysis for nine fasciolicides (closantel, rafoxanide, oxyclozanide, niclosamide, nitroxinil, ioxynil, 4-nitro-3-(trifluoromethyl)phenol, salicylanilide, and triclabendazole) and three metabolite residues (ketotriclabnedazole, triclabendazole sulfone, and triclabendazole sulfoxide) in milk and infant formula was established. The samples were extracted and purified through solid-phase extraction and analyzed using LC–MS/MS. The proposed method demonstrated high accuracy (the average recoveries ranged from 70.5 % to 107.4 %) and high sensitivity (the limits of quantification ranged from 1.0 to 25.0 µg/kg). This method was successfully applied to determine nine fasciolicides and three metabolite residues in 45 milk and infant formula, providing technical support for the safety and quality evaluation of dairy products. [ABSTRACT FROM AUTHOR]

[Display omitted] • A GC-Q-Orbitrap HRMS method was developed for broad screening of 104 steroids. • GC separation, ionization energy and resolution were optimized. • Analysis of incurred samples shows good performance for detecting steroid abuse. • Method was applied on bovine urine samples from Dutch National Residue Control Plan. • Generic sample preparation and untargeted data acquisition facilitate future risk-based monitoring. Steroids are a large and diverse group of molecules containing both natural hormones and synthetic derivatives. Steroid administration can have a growth-promoting effect in food-producing livestock. However, the exogenic use of steroids to promote growth has adverse health effects in livestock and consumers, and, consequently, is forbidden in the European Union (EU). Therefore, broad monitoring of steroids and other growth-promoting compounds in animal matrices is desirable. Commission Implementing Regulation (EU) 2021/808 was recently implemented to provide explicit room and quality guidance for analyzing food residues, including steroids and growth-promoting compounds, using the technique of high-resolution mass spectrometry (HRMS). This manuscript presents a method for broad steroid monitoring in animal urine by gas chromatography (GC) Q-Orbitrap HRMS, using a minimal cleanup of liquid–liquid extractions and a 96-well plate solid-phase extraction (SPE). An in-house library was built to detect 104 steroid and steroid-like molecules from subclasses of androgens, estrogens, progestogens, stilbenes, and resorcylic acid lactones (RALs) in the HRMS datafiles. The method was fully validated according to Regulation (EU) 2021/808 as a qualitative screening method for bovine and porcine urine, and used for analysis of bovine urine samples originating from previously performed animal studies and from the Dutch National Residue Control Plan. Analyses of samples from previous animal studies show performance of the developed method for monitoring synthetic steroid misuse, as all incurred samples were flagged non-compliant. To our knowledge, it is the first time a method was developed and validated with such a broad scope of growth promoters in cattle with GC-HRMS. Since the sample preparation is generic for multiple steroid classes, and the HRMS data acquisition is untargeted, the generated data can be used for further expansion of the scope with other steroids, for investigating unexpected or new steroids, and for retrospective (trend-)analysis, thus facilitating risk-based monitoring of steroids and other growth promoting compounds. [ABSTRACT FROM AUTHOR]

In this study, we developed a simple screening procedure for the determination of 18 anthelmintics (including benzimidazoles, macrocyclic lactones, salicylanilides, substituted phenols, tetrahydropyrimidines, and imidazothiazoles) in five animal-derived food matrices (chicken muscle, pork, beef, milk, and egg) using liquid chromatography-tandem mass spectrometry. Analytes were extracted using acetonitrile/1% acetic acid (milk and egg) and acetonitrile/1% acetic acid with 0.5 mL of distilled water (chicken muscle, pork, and beef), and purified using saturated n -hexane/acetonitrile. A reversed-phase analytical column and a mobile phase consisting of (A) 10 mM ammonium formate in distilled water and (B) methanol were used to achieve optimal chromatographic separation. Matrix-matched standard calibration curves (R 2 ≥0.9752) were obtained for concentration equivalent to ×1/2, ×1, ×2, ×3, ×4, and ×5 fold the maximum residue limit (MRL) stipulated by the Korean Ministry of Food and Drug Safety. Recoveries of 61.2–118.4%, with relative standard deviations (RSDs) of ≤19.9% (intraday and interday), were obtained for each sample at three spiking concentrations (×1/2, ×1, and ×2 the MRL values). Limits of detection, limits of quantification, and matrix effects were 0.02–5.5 μg/kg, 0.06–10 μg/kg, and −98.8 to 13.9% (at 20 μg/kg), respectively. In five samples of each food matrix (chicken muscle, pork, beef, milk, and egg) purchased from large retailers in Seoul that were tested, none of the target analytes were detected. It has therefore been shown that this protocol is adaptable, accurate, and precise for the quantification of anthelmintic residues in foods of animal origin. Image 1 • Multi-class determination of 18 anthelmintics in animal-derived food matrices were screened. • Samples were extracted using LLE and analyzed by LC-MS/MS. • The developed method provided satisfactory sensitivity and linearity. • None of the market samples was found to contain any measurable residues of the tested analytes. • The developed protocol is adaptable, accurate, and precise for quantification in foods of animal origin. [ABSTRACT FROM AUTHOR]

For nearly 70 years scientific techniques have been routinely applied in archaeological research. Yet some artefacts hold such cultural significance that sampling is inappropriate, restricting the methods that can be brought to bear in their analysis. Such restrictions often apply to rock art, especially where research is directed by the indigenous peoples who have stewardship over not only the site fabric, but its inseparable cultural context. Here we report a multi-technique program of in-field and laboratory-based analyses to describe the materiality of a painted rock art site in Nyiyaparli country, in the Central Pilbara region of Western Australia. The relationship between the rock art, nearby potential pigment sources and evidence for ochre processing at the site was investigated using in situ portable X-Ray Fluorescence and optical microscopy, with interpretations aided by field and laboratory-based residue analysis of grinding related stone artefacts and X-Ray Powder Diffraction of potential ochre sources. Our findings provide an example of the nuanced interpretations that scientific analyses can add to rock art investigations. Our work suggests that local materials were used in the production of painted art and that ochre processing was ubiquitous at the site and other nearby rockshelters. Combined with the placement of rock art in a hidden context within the site, we suggest the panels at BBH15-01 were part of in-group events and that art and ochre processing in the Baby Hope study area were part of everyday activities. [ABSTRACT FROM AUTHOR]

Residue analysis is a sub-discipline in archaeology that uses a variety of techniques which can be useful for determining the function of prehistoric stone tools. Past experimental studies have revealed the non-diagnostic nature of residues under reflected light microscopy and the challenges of identifying them as plant or animal and assigning them to a specific origin (i.e. use-related vs incidental). Recently, new contextual approaches and analytical techniques have addressed these limitations. Prior studies have suggested that use-related and incidental residues can be identified on stone tool surfaces based on differences in distribution patterns. Location, residue frequency, and associations with other residues are often the main criteria used in these studies to distinguish use-related from incidental residues, while other contextual information such as directionality, aspects of crushing and smearing, or dispersion from the working edge are often ignored. Moreover, the integration of chemical information provided by other analytical techniques into these contextual approaches that address residue mapping has received little attention. In this study, we address these issues and combine contextual information recorded through 3D digital microscopy with elemental compositions obtained through SEM-EDX to better identify different animal and plant residues on experimental stone tools. Based on an experimental sample tested under outdoor field conditions, we show how identification issues in fresh undamaged residues are not only restricted to the ambiguity between different use-related remains, but also the ambiguity between the latter and incidental residues. We demonstrate the versatility of 3D DM in recording in-situ contextual information of fresh residues (distribution patterns, invasiveness, disposition of specific tissues indicating tool-use direction, and aspects of crushing and smearing) and how supporting this information with the elemental composition obtained through SEM-EDX and element maps can help to improve identification of ambiguous residues, both use-related and incidental. Although more experiments are needed, the multi-analytical contextual approach tested here provides an example of in-situ characterization of fresh undamaged residues in experimental tools that can be conducted before performing post-depositional experiments or using other analytical techniques and extraction protocols. [ABSTRACT FROM AUTHOR]

This paper presents the conclusions of an archaeometric study on two unique artefacts associated with the Early Bronze Age (EBA) Mierzanowice culture (MC) of south-eastern Poland. Two decorated animal bone pins were found in sepulchral context, each accompanying the skeletal remains of a young woman. Based on previous use-wear analysis, the artefacts are interpreted as clothing pins. Their main characteristic is a geometric decorative pattern in the form of incisions and grooves, filled with a dark, grainy substance. Additionally, one of the pins has a distinct green colouration, which extends over uneroded areas of the surface. An array of imaging and spectrometric techniques was employed to investigate both the inlay and the green staining. While the colouration appears to be post-depositional, the dark substance, identified as fine-grained quartz (possibly raw faience paste) mixed with a black, soot-based pigment (bistre) of adhesive properties, was intentionally applied to the surface of both artefacts. This finding reveals a broad range of skills employed by the craftsperson to manufacture the objects. EBA was a time of emerging specialisation and social stratification, during which local artisans worked within a micro-region producing 'special' items that were both functional and socially meaningful. [ABSTRACT FROM AUTHOR]

This paper focuses on the functional analysis of a specific oval shaped basin diffused in Lower Egyptian Predynastic sites during the first half of the 4th millennium BC. These oval shallow ceramic basins are characterised by a flat and wide inner surface that is covered by a layer of small rock fragments pressed into the clay matrix. Several archeologists have interpreted them as grinding tools, but the limited number of samples unearthed thus far and their poor state of preservation made this interpretation uncertain. Here we present the results of a preliminary integrated study based on the combination of experimental archaeology and petrographic, use-wear and residue analyses carried out on two samples from the Predynastic site of Maadi. The use-wear analysis of the archaeological fragments highlighted traces of an intentional grinding and light pounding of oily substances, which is also partially supported by the organic residue investigation. These results were tested through experimental tests that confirmed these basins are most likely mortars. Establishing the actual functional activities performed in such a unique type of vessel is important not only for understanding the social behaviors of the Lower Egyptian Predynastic communities and the dynamics related to the diffusion of such basins, but it also provides a new methodological framework for Egyptian Predynastic studies. [ABSTRACT FROM AUTHOR]

Immunoassays such as the enzyme-linked immunosorbent assay (ELISA) are utilized extensively for detecting protein biomarkers and small molecules in healthcare, environmental monitoring, and food analysis. Unfortunately, the current strategies for immunoassays often require sophisticated apparatus such as a microplate reader, which might not be available in resource-limited areas. To mitigate this problem, we designed a compact smartphone based-device and a multicolor response immunosensor. First, we designed a compact and cost-effective 3D-printed attachment, where a light-emitting diode was used as a light excitation source and a smartphone captured the fluorescent emission signals. Second, by combining quantum dots hybrid and chemical redox reaction, multiple color responses were displayed in the presence of the analyte at different concentrations. Third, solutions with distinct tonality could be readily distinguished by the naked eye and they were suitable for quantitative analysis using the hue-saturation-lightness color space based on a smartphone application. The versatility of the proposed sensing system was demonstrated by implementing an indirect competitive ELISA for analyzing trace drug residues in foodstuffs. The multicolor response of this sensing strategy allows us to visually quantify drug residues in foodstuffs. Moreover, the smartphone-based immunosensor can assess the exact concentration of the analyte by using a self-designed mobile application. The proposed assay provides a highly sensitive performance that the limit of detection was 0.37 ng/mL by visual detection and 0.057 ng/mL using the compact device. Due to its advantages in terms of portability, straightforward visual detection, high sensitivity, and cost effectiveness, the proposed immunosensor has great potential for applications in areas without access to laboratories or expensive infrastructure. Image 1 • A ratiometric fluorescent immunosensor based on quantum dots hybrid and smartphone. • A multiple fluorescence color changes enabled highly sensitive visual detection. • A smartphone-based device was designed as a compact and sensitive readout system. • The smartphone-based device was used for on-site analysis of drug residues. [ABSTRACT FROM AUTHOR]

Soil health is closely linked to the sustainable development of agriculture, and soil microorganisms are the fundamental and pivotal components in maintaining soil health. Atrazine (ATZ) is a triazine herbicide widely used worldwide, and its ecotoxicity to soil microorganisms has been widely studied. However, previous studies have focused on investigating the ecotoxicity of ATZ active ingredients under laboratory conditions. The damage caused by ATZ formulations to soil health in the actual field environment cannot be ignored. Herein, the toxicity of ATZ formulations (1140 and 1710 g hm−2) in maize fields after 1, 28, and 72 d of exposure was investigated in terms of soil microbial abundance, community structure, soil enzyme activities, functional gene abundance, and ATZ residues. The results showed that ATZ disturbed the microbial functions that maintain soil health by disturbing soil nutrient and carbon cycling as well as enhancing pollution degradation. The promotion of both urease activity and AOB- amoA gene abundance indicated that ATZ accelerated the loss of nitrogen from soil, which was detrimental to soil nitrogen cycling. The abundances of the Pontibacter genus and the cbbLG gene were inhibited, indicating that the ability of soil carbon dioxide fixation was hindered. The abundance of Lysobacter , which helps to degrade pollutants, increased. The integrated biomarker response indicated that the comprehensive toxicity of ATZ to soil microorganisms increased with dose. Additionally, the DT 50 of ATZ in agricultural soil was 5.4–5.7 d, and the residual level of ATZ in crop grains was in line with the maximum residue limit recommended by the European Union and China. The findings of the present study reflect the effects of ATZ formulation on soil microbes in the actual agricultural environment and provide insights into the mechanisms of soil health regulation mediated by microorganisms. • No significant-effect was found on soil bacteria and fungi abundance. • The functions of soil nutrients and carbon cycling were negatively affected. • Atrazine increased the abundance of genera related to pollutant degradation. • The final levels of atrazine residues in grains were lower than the MRLs. • A dose-effect relationship was found regarding atrazine toxicity. [ABSTRACT FROM AUTHOR]

• A rapid method for dyes determination in aquaculture products was developed. • An oxidizing step introduced to quantitate parent forms. • Fingerprints comparison as developed tool to monitor illegal dyes in aquaculture. • Study of metabolome led to some endogenous and exogenous metabolites discovering. The aim of the study was to initiate an exhaustive strategy of control by implementing both targeted and non-targeted metabolomics approaches. A LC–MS/MS method including an oxidative step for most of dyes was developed and validated to target the analysis of 14 residues belonging to different families of dyes. The method was suitable for the quantitative confirmation of 13 dyes at low ppb levels. The metabolomics approach objective was to compare fingerprints between farmed fish treated with malachite green and farmed fish treated with victoria pure blue bo. Analytical information on modifications in the metabolome of muscle, liver and plasma was exploited by HRMS following by multivariate statistics and revealed some direct or endogenous metabolites among relevant mass features contributing to the constructed models. These two approaches, either appropriate biomarkers either enlarged targeted dyes are explored concomitantly to help improving the strategy for tracking new illegal practices in aquaculture. [ABSTRACT FROM AUTHOR]

Veterinary drug residues have become a major source of environmental pollutants. To monitor trace salbutamol (SAL) in the environment, a highly sensitive and reliable time-resolved fluoroimmunoassay (TRFIA) was developed. Under the optimum parameters, the half-maximal inhibition concentration (IC 50) and the limit of detection (LOD, IC 10) were determined to be 0.08 μg/L and 0.66 ng/L with a linear range (IC 20 - IC 80) of 0.0028–2.25 μg/L for SAL. The IC 50 and LOD of the TRFIA improved approximately 5-fold and 31-fold, respectively, when compared with our previously reported ELISA data. When compared to most other conventional methods, the TRFIA also showed an excellent sensitivity and accuracy for the detection of SAL. Recoveries from 83.4 to 111.3% and standard deviations (RSDs) from 3.9 to 14.0% were observed in various environmental SAL-spiked samples, including river water, paddy water, livestock wastewater, vegetable field soil and rice paddy soil. In addition, the developed TRFIA showed largely consistent with analytic results from UPLC-MS/MS (R2 = 0.9825, n = 15). These results suggest that the proposed TRFIA can be applied as a sensitive and reliable monitoring method to detect trace SAL in environmental samples. Unlabelled Image • A highly sensitive time-resolved fluoroimmunoassay (TRFIA) for the detection of salbutamol was developed. • The TRFIA gave largely consistent results and showed good correlations with the referential method of UPLC-MSMS. • The developed TRFIA appears to be a useful method for monitoring trace salbutamol in environmental samples. [ABSTRACT FROM AUTHOR]

• A novel method to obtain the stoichiometry of the ternary mixtures. • Thermal analysis of ternary mixtures in confined and unconfined test conditions. • The stoichiometric wt% of ternary mixture was 53% KNO 3 : 33% Al: 14% S. The aim of the study was to understand the thermal reactions of pyrotechnic flash compositions comprising ternary mixtures of potassium nitrate, Aluminium and Sulphur, and attempted to optimize the stoichiometry of the composition through residue analyses for best results. Differential Scanning Calorimetry (DSC) was used for the thermal reaction studies, and X-ray diffraction (XRD) and Scanning Electron Microscopy with Energy Dispersive X-ray Spectroscopy (SEM-EDS) for the residue analysis. The flash compositions containing KNO 3 /Al/S were more reactive under confined test conditions (sealed container) than in unconfined conditions (open container). The residue analysis results showed that the optimal stoichiometric mixture for pyrotechnic flash composition (KNO 3 /Al/S) was 53/33/14 by weight. The stoichiometric composition was experimentally validated by proving complete combustion and this mixture was found to have the highest heat release (637 J/g) of all the compositions studied. [ABSTRACT FROM AUTHOR]

Abstract Middle Pleistocene hominins occupied Europe as early as 700 ka. Data on subsistence and adaptation to environment remain limited due to the small number of sites, especially from 700 to 500 ka. Current consensus suggests that Middle Pleistocene populations periodically peopled and depopulated areas of Europe in response to climatic fluctuations. Most occupations are located in the South, while the North-West was only occupied during favorable climatic periods. During this time, significant behavioral changes occur, such as bifacial technology and more complex modes of flaking. Further north in France, in the Loire basin, the site of la Noira has well-developed bifacial tools at around 700 ka, The site is located along a river with abundant millstone slabs which were flaked on the site suggesting it may have served partially as a lithic workshop. We employ use-wear and residue analysis (optical light and scanning electron microscopy) of stone tools to reconstruct early Acheulean hominin behavior. While the lithics are composed largely of retouched and unretouched debitage, large cutting tools (bifaces and cleavers) are also present. We demonstrate that la Noira was not only a lithic workshop, but that a broad range of resources were being used by the hominins at the site, including wood, plants, mammals, and possibly birds and fish. Finally, we compare our results with contemporary sites and suggest that, in the early European Acheulean, Middle Pleistocene hominins had detailed local environmental knowledge, and were able to adapt to a wide range of environments, including cool, temperate, and Mediterranean. Highlights Major contributions: • The site served as both a lithic workshop and a base for foraging activities. • Middle Pleistocene hominins exploited a wide range of resources (plants, wood, animals, and possibly fish and birds). • Crudely made and unfinished bifaces were used for the same tasks as completely finished bifaces. [ABSTRACT FROM AUTHOR]

In this study we describe an approach to enhance the sensitivity of an online comprehensive two-dimensional liquid chromatography (LC × LC) high-resolution mass spectrometry method for the separation and detection of trace levels of anabolic-steroid residues in complex urine matrices. Compared to one-dimensional liquid chromatography (1D-LC), LC × LC methods offer higher separation power, thanks to the combined effect of two different selectivities and a higher peak capacity. However, when using state-of-the-art LC × LC instrumentation, the price paid for the increase in separation power is a decrease in sensitivity and detectability of trace-level analytes. This can be ascribed to the sample dilution that takes place during each of the two chromatographic steps. The way in which fractions are collected and transferred from the first to the second column is also of paramount importance, especially the volume and the solvent composition of the fractions injected in the second column. To overcome the detection limitation, we present an active-modulation strategy, based on concentrating the fractions of the first-dimension effluent using a modulation interface that employs trap columns. We obtained a signal enhancement for anabolic-steroid compounds in a bovine-urine sample by a factor of 2.4–7.6 and an increase in the signal-to-noise ratio up to a factor of 7 in comparison with a standard loop-based modulation interface. In addition, thanks to the increased sensitivity of our method, a substantially larger number of peaks were detected (76 vs. 36). Moreover, we could reduce the solvent consumption by a factor of three (160 mL vs. 500 mL per run). [ABSTRACT FROM AUTHOR]

A chromatographic method involving a single run was validated for the quantification of clanobutin, dichlorvos, and naftazone in products of animal origin. Pork, beef, chicken, milk, and egg samples were extracted with a solution of 0.1% formic acid in acetonitrile, defatted with n -hexane, centrifuged, and filtered prior to analysis using liquid chromatography-tandem mass spectrometry (LC-/MS/MS). The analytes were separated on a C18 column using a solution of 0.1% formic acid and 10 mM ammonium formate (A) and acetonitrile (B) as the mobile phase. A good linearity over 5–50 ng/g concentration range was obtained with coefficients of determination ( R 2 ) ≥ 0.9807. The intra- and interday accuracy (recovery %) calculated from 3 fortification levels (5, 10, and 20 ng/g) were 73.2–108.1% and 71.4–109.8%, and the precisions (expressed relative standard deviations (RSDs)) were 0.9–12.9% and 1.8–10.6%, respectively, for the 3 tested analytes in animal originated foods. The limits of quantification (LOQs) ranged between 0.1 and 1 ng/g, thus enabling the quantification of residual levels below the uniform maximum residue limit (MRL) of 0.01 mg/kg set for compounds having no MRL. The designated methodology was successfully applied to monitor various samples collected from Seoul; the tested analytes were not quantified in any of the market samples. Conclusively, the developed method is simple, sensitive, and accurate, and could be used for the detection of pharmaceuticals in various animal food matrices with variable protein and fat contents. [ABSTRACT FROM AUTHOR]

A confirmatory method for the determination of colistin in animal tissues, egg, milk, and feed was developed and validated. Colistin A and colistin B were extracted from samples with the mixture of 10% trichloroacetic acid-acetonitrile and isolated with mixed-mode weak cation exchange cartridge. Analytes were separated from matrix components using ultra-high performance liquid chromatography, and detected with electrospray ionization on a triple quadrupole mass spectrometer. Mean recoveries ranged from 78.0% to 115.6% with intra-day and inter-day relative standard deviation lower than 8.4% and 12.4%, respectively. The quantitation limits for different matrices were between 5 and 30 μg/kg, which was satisfactory for surveillance monitoring. The developed method was applied to the analysis of real samples collected from different provinces of China, and 19 out of 348 samples were found to be contaminated, with the highest concentration of approximately 12,000 μg/kg colistin A and 10,000 μg/kg colistin B in feed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Imazalil used in postharvest for disease and pest control in papaya. • Monitoring the dissipation/migration of imazalil in papaya skin, pulp, and seeds. • Extraction and chromatographic methods for determination of pesticide residues. • Evaluation of papaya physicochemical parameters during refrigerated storage. Methods involving solid-liquid extraction with low-temperature partition and analysis by gas chromatography coupled to mass spectrometry (GC–MS) were validated to investigate the dissipation/migration of residues of the postharvest fungicide imazalil in papaya skin, pulp, and seeds. The fruits were stored for 23 days (14 °C). Every two days, fruits from the control group and those treated with imazalil had their skin, outer pulp, inner pulp, and seeds separated and then analyzed by GC–MS. After the 23rd day, about 70% of the imazalil had dissipated. Most of the remaining residue was found in the skin; however, the small amount migrating into the pulp was above the maximum residue levels allowed by the regulatory agencies. Imazalil residue was also detected in seeds at concentrations lower than the LOQ (0.025 mg kg−1). Mass loss was the only quality parameter that showed a significant difference between the fruits of the control and study groups. [ABSTRACT FROM AUTHOR]

The aim of the present study was to assess the toxic effects of pyraclostrobin on DNA damage and antioxidant enzymatic activities in the zebrafish ( Danio rerio ) liver. Based on the 96-h median lethal concentration (96 h LC 50 , 0.056 mg/L) of this chemical, fish were exposed to three doses (0.001, 0.01, and 0.02 mg/L) and sampled on days 7, 14, 21 and 28 after the initiation of a subchronic toxicity test. The levels of superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA), glutathione S-transferase (GST), reactive oxygen species (ROS) and DNA damage were determined. The amount of pyraclostrobin residue in the water was also measured. The concentrations in the three treatment groups varied no more than 5% during the exposure periods, indicating that pyraclostrobin is relatively stable during this time in an aquatic environment. ROS and MDA levels significantly changed in a dose dependent manner during the experiment. Enzymatic activities were inhibited to a certain extent. DNA damage was significantly enhanced. These results collectively indicate that pyraclostrobin induces oxidative stress and DNA damage in zebrafish. [ABSTRACT FROM AUTHOR]

Nitric oxide (NO) is a newly discovered fumigant which is effective against a wide range of postharvest pests. To register NO with US EPA for commercial use as a pesticide and to ensure its safety to consumers, it is necessary to analyze residues of NO fumigated products. In this study, we analyzed nitrate (NO 3 − ) and nitrite (NO 2 − ) ion concentrations in liquid extracts as residues on 20 fresh products at 24 h after 16 h fumigation treatments and compared them from untreated controls to determine effects of nitric oxide fumigation. Each product was subjected to two identical NO fumigation treatments except one treatment was terminated by flushing with N 2 and the other terminated by flushing with air. For most products, there were no significant differences in NO 3 − or NO 2 − level between the treatment that was terminated with nitrogen flush and the control. Only when NO fumigation treatment was terminated by flushing with normal air, there were significantly higher NO 3 − and NO 2 − concentrations in all fumigated products than both control and N 2 flushed fumigated products. NO 2 − concentration was generally not detectable in both fumigated and control products. Therefore, our results indicated that there were no significant levels of residues from NO fumigated fresh products at 24 h after fumigation when fumigation was terminated properly with nitrogen flushing. [ABSTRACT FROM AUTHOR]

Antibiotics are used in ethanol production to discourage the growth of bacteria that would result in lower ethanol content and a lower quality product. A survey conducted by the FDA (FY 2010 Nationwide Survey of Distillers Grains for Antibiotic Residues, 2009 [1]) revealed that the residues of these antibiotics can remain in the distillers grains (DG) by-product, which is used as an animal feed ingredient. The low levels of antibiotic residues in DG could be a public health concern, as they could lead to antimicrobial resistance. To enable the quantitative determination of these antibiotics (erythromycin, penicillin G, virginiamycin M1 and virginiamycin S1), we developed a sensitive LC–MS/MS method. The residues were extracted from distillers grains with a mixture of acetonitrile and buffer followed by acetonitrile. The combined extract was diluted with water and washed with hexane. An aliquot was cleaned up on an Oasis HLB solid phase extraction cartridge. Extracts were analyzed by LC-tandem mass spectrometry. The method was successfully validated using a variety of different matrices such as corn DG, corn & milo DG, and deoiled corn DG. Absolute recoveries of the analytes ranged from 53 to 106%. Accuracy ranged from 90 to 101% based on calibration by matrix standards. The limits of quantitation and relative standard deviation were all satisfactory to support future surveillance studies. [ABSTRACT FROM AUTHOR]

Analysing residues on stone tools can reveal precise information about the activities that were conducted with the lithic tool and is a valuable technique to reconstruct past human behaviours. However, it is often difficult to assess the nature of the relationship between a residue and the artefact on which it is found. It is of great importance, therefore, to determine whether residues are use-related or a result of contamination. Here, we conducted experiments with 99 tool replicas made of red jasper, processed 15 different plant taxa and mapped the distribution of residues against the use-wear traces. Our experiments addressed several questions on the spatial relationship between use-wear and use-related residues on stone tools. In the majority of cases the residues were not spatially associated with use-wear. Therefore, it appears that residues should not necessarily be considered as non-related to use because they are not in close proximity to use-wear. On the other hand, our experiments also showed that the problem of contamination should not be underestimated and can be a serious cause for misinterpreting stone tool functions. Finally, our results showed a variability in residue distribution between tools used to process different plant taxa and revealed that the water content in the contact material has an influence on residue distribution. [ABSTRACT FROM AUTHOR]

• Deethylene-ENR was screened and detected in real fish samples for the first time. • A new method for residue analysis of ENR and its metabolites in fish was developed. • The detection rate of ENR metabolites in the analyzed crucian carp samples was high. • Deethylene-ENR may be of concern as a possible risk candidate in aquatic products. The abuse of enrofloxacin (ENR) in aquaculture and the lack of monitoring of other metabolites except ciprofloxacin (CIP) may lead to unknown harmful effects on human health. In this study, ENR metabolites were screened in real fish samples based on ultrahigh-performance liquid chromatography coupled with Q-Orbitrap mass spectrometry combined with Compound Discoverer software, and another metabolite deethylene-ENR besides CIP was detected and identified for the first time. Correspondingly, a method for the determination of ENR and CIP and the semi-quantitative analysis of deethylene-ENR in aquatic products was established. Method validation illustrated that excellent linearity and satisfactory recoveries of analytes were obtained. Limits of detection of ENR and CIP were both 0.1 μg kg−1, and their limits of quantification both 1 μg kg−1. CIP and deethylene-ENR were detected in 12 of 14 ENR-positive fish samples, so deethylene-ENR should be of concern as a possible risk candidate in aquatic products. [ABSTRACT FROM AUTHOR]

[Display omitted] • We firstly developed an analytical method for cyetpyrafen and its metabolites. • The uptake and metabolism of cyetpyrafen in soil–strawberry system was evaluated. • Cyetpyrafen and M−309 mainly accumulated in strawberry fruits by foliar spray. • Cyetpyrafen showed poor top-down and bottom-up movement within plants. • The dissipation of cyetpyrafen in orange fruits and peels was examined. Novel insecticide cyetpyrafen is frequently used in various crops, however, knowledge of its fate in crops and environments is largely unexplored. In this study, an effective method was firstly established for simultaneous determination of cyetpyrafen and its metabolites (M−309 and M−391) in 13 matrices (e.g., plants and soils) to explore their fate. Mean recoveries of the three compounds ranged from 73.1 % to 118.7 % with the relative standard deviations (RSDs) less than 17.9 %. Further, after 28 days of exposure in a field soil-strawberry system, cyetpyrafen and M−309 exhibited great accumulations in strawberry leaves by foliar spray while both compounds were predominately accumulated in roots by root irrigation, where cyetpyrafen was poorly translocated within plant. An equal amount of M−309 was measured in both strawberry plants and soils indicates the extensive transformation of cyetpyrafen in soil-strawberry system. Therefore, metabolism of cyetpyrafen in foods need to be considered for its better risk assessment. [ABSTRACT FROM AUTHOR]

Pilot experiments involving the butchering of bird carcasses and the use of non-retouched flint flakes were performed. The executed actions comprised skinning and defeathering various avifaunal species ( Circaetus gallicus and Gyps fulvus ). The main aim of this experimental programme was to document the use-wear on flint implements employed in the treatment of the avifaunal carcasses in order to help researchers identify this activity in the archaeological record. An additional focus of this study concerned the experimental organic residues (soft tissue and feathers) associated with the bird species used in the experiments. For each residue type, a detailed chemical elemental analysis and morphological characterisation were performed, with the aim of creating an experimental database for comparison with the micro-residues that will potentially be found on archaeological stone tools. For microscopic observations, we employed both Scanning Electron Microscopy (SEM) and Optical Light Microscopy (OLM). A detailed description of the use-wear features and residue types was achieved through a systematic comparison of micrographs taken with both techniques. In addition, EDS (energy-dispersive x-ray spectroscopy) was applied to determine the elemental composition of the residues. Taphonomic analysis of the bones of the carcasses used in the experimental programme was performed with the principal aim of comparing the distribution of cut marks on bones with the use-wear pattern on the lithic implements employed. Future developments of our research will improve the methodology by expanding the experimental programme and by applying it to archaeological collections (at sites where the processing of these kinds of animals has already been identified). [ABSTRACT FROM AUTHOR]

Sensitivity enhancement for residue analysis of ciprofloxacin and norfloxacin in surface water was performed by liquid chromatography with fluorescent detection (LC-FD). Labelling of both drugs were studied with fluorescent probes (e.g. Nile blue perchlorate (NBP) and 4- (N,N-Dimethylaminosulfonyl)-7-(N-chloroformylmethyl-N-methylamino)-2,1,3-benzoxadiazole (DBD-COCl). Factors affecting the derivatization (e.g. stoichiometric ratios, reaction time and base catalysts) were optimized. The derivatization was achieved in 15 min using a stoichiometric ratio between the substrate and DBD-COCl of 1:3, whereas NBP gave unsatisfactory results. Separation of the derivatives by LC was achieved (resolution (R S ) > 1.8) on a C8 column using a mobile phase consisting of 50 mM formic acid and acetonitrile (ACN) (68:32% v/v) in 20 min. The method was linear ( r 2 > 0.99) in a range of 200–2,000 µg/L, precise (%RSD < 9.17) and accurate (%recovery of 102.5–122.2%) for the determination of the derivatives. The uses of fluoroquinolone molecularly imprinted polymer in conjunction with hydrophilic-lipophilic balance sorbents demonstrated an efficient procedure for sample pre-concentration and clean-up for water sample resulting in the improved percent recovery. Applications of the proposed method was shown in surface water samples in Thailand. [ABSTRACT FROM AUTHOR]

The extensive use of cartap, a water soluble carbamate pesticide, raises the possibility of its undesirable toxicity to non-target organisms. Agricultural run-off and vector control sprays are the major sources of exposure to this pesticide for fresh water aquatic organisms. We therefore hypothesized that these sub-lethal yet environmentally significant concentrations of cartap has toxicological implications on fingerlings of Labeo rohita. The rationale of the study was to assess biochemical, histological responses and residue analysis in vital organs of L. rohita exposed to cartap hydrochloride after 24, 48, 72 and 96 h of exposure. An attempt has been made to elucidate the sub-lethal toxicity of cartap exposure on biomarker enzymes related to vital organs of L . rohita . The results clearly exemplify that exposure to sub-lethal concentration of cartap (0.3551 mg/L −1 for 96 h) was reflected in tissue concentrations of pesticide with significant alterations in the biomarker enzymes Acetylcholineesterase activity(AChE), Alanineaminotransferase(ALAT), Asparatateaminotransferase(AAT), alkaline phosphatase(ALP) and superoxide dismutase(SOD). Increased abnormalities in the liver function test coupled with an augmented antioxidant stress response (SOD activity) were noticeably observed in gills, liver and brain respectively. The presence of total cartap pesticide residues in fish tissue were determined by reverse phase high-performance liquid chromatography coupled with UV-detector. The LOD and LOQ of cartap residues in the exposed tissue samples were determined as 0.1(µg/L) and 0.012(µg/L) respectively. However, the tissue injuries were clearly evident from the morphological and nuclear anomalies in the hematoxylin and eosin stained sections of gill, liver and kidney suggested that cartap is moderately toxic to the L . rohita . [ABSTRACT FROM AUTHOR]

Background Aquaculture is one of the worldwide strategic development fields, and its importance is evident in its significant worldwide growth in the last decades. This growth is associated with the implementation of intensive and semi-intensive production methods, with the use of antibiotics in order to prevent the emergence and spread of infectious diseases in fish. Fluoroquinolones, tetracyclines, and sulfonamides, among others, are widely used for this purpose. This practice constitutes a real public health concern, not only due to the presence of antimicrobial residues in edible tissues, which can cause allergic reactions in hypersensitive individuals, but also due to the emergence of bacterial resistance. Consequently, the European Union's Regulatory Agencies have established maximum residue limits and specific requirements regarding the performance of analytical methods. Scope and approach This article reviews the most recent analytical methodologies concerning antimicrobial residues in fish, reported in the literature, given emphasis on sample procedures, extraction/purification methods, chromatographic conditions and validation techniques according to legislation. Key findings and conclusions Liquid chromatography coupled to mass spectrometric detection is used as preferential tool in the analysis of antimicrobial residues in fish. The current analytical strategy is shifting towards multi-residue and multiclass methods, which save time, and surely represent the future trend in this field. The extraction process still represents the limiting factor of any multi-residual method, since it should provide acceptable recovery of all analytes with a broad range of physicochemical properties, and therefore this is probably the step that requires more in-depth research. [ABSTRACT FROM AUTHOR]

A new high-performance liquid chromatography with ​fluorescence detection (HPLC-FLD) method was developed for determination of piperazine residues in food animal products. Samples were extracted with formic acid in water and purified using the PCX cartridge. Following purification, the samples were derivatized using dansyl chloride, and the analyte was separated using water/acetonitrile as a mobile phase. The calibration curves showed good linearity over a concentration range of 20–120 ng/g with coefficient of determination ( R 2 ) ⩾ 0.996. The intra-day accuracy (presented as recovery %) and precision (presented as relative standard deviation, RSD %) were 81–97.3% and 0.83–6.87%, whereas, the inter-day values were 80.5–96.8% and 1.7–6.8%, respectively. The limit of quantification (LOQ) was 20 ng/g, which was considerably lower than the maximum residue limit (MRL). The developed method was used to monitor market samples, and piperazine was not detected in any of the samples. To our knowledge, this is the first study in which the detection of piperazine in various food and animal products by using a sensitive and reliable analytical method has been described. [ABSTRACT FROM AUTHOR]

A sensitive and selective HPLC–MS/MS method was developed for the quantitative analysis of dicamba residues in raw agricultural commodities (RACs). Instead of analysis in the traditionally used negative electrospray ionization (ESI) mode, these anionic compounds were detected in positive ESI with the use of ion-pairing reagents. In this approach, only a small amount (60 µM) of a commercially available dicationic ion-pairing reagent was introduced into the post-column sample stream. This method has been validated in six different types of RACs including corn grain, corn stover, cotton seed, soybean, soy forage and orange with satisfactory quantitative accuracy and precision. The limits of quantitation (LOQ) values for these analytes were 1.0 to 3.0 µg/kg. The standard curves were linear over the range of the tested concentrations (3.0 to 500 µg/kg), with correlation coefficient ( r ) values≥0.999. Evaluation of ionization effects in RAC matrix extracts using diluent blanks for comparison showed no significant matrix effects were present. [ABSTRACT FROM AUTHOR]

Phytanic acid diastereomers, 3 S ,7 R ,11 R ,15-phytanic acid ( SRR ) and 3 R ,7 R ,11 R ,15-phytanic acid ( RRR ), were determined by GC–MS in extracts of archaeological ceramic. The SRR % was higher in pottery from coastal sites corresponding with 13 C enriched n -alkanoic acid corroborating a predominantly marine origin for the food residues. Conversely, low SRR % and 13 C depleted n -alkanoic acid were found at inland sites, which are most likely derived from ruminant products. These observations are explained by differences in the bacterial transformation of phytol to phytanic acid between ruminant and aquatic organisms and allow these products to be easily distinguished in archaeological contexts. [ABSTRACT FROM AUTHOR]

Understanding the relationship between stone tool technology and Late Pleistocene hominins has been one of the most fundamental questions within the field of human evolution. While this question has traditionally been addressed through the technological and typological study of lithic remains, improvements in detecting and identifying stone tool residues offer new avenues for reconstructing Late Pleistocene stone tool technologies. However, the possible contribution of stone tool residues in the reconstruction of Late Pleistocene stone tool technologies remains unclear due to unsolved methodological issues. The remaining issues include uncertainties concerning the exact role of optical microscopy, the effect of the depositional context on residue preservation and the effect of (post-)excavation treatment. This paper explores the possible contribution of stone tool residues through a large-scale residue analysis of a lithic assemblage from Grotta di Fumane, including stone tools from Middle and Upper Palaeolithic layers. Including different microscopic techniques, lithics from different depositional contexts and treated through different (post-)excavation procedures allowed the verification of the effects of all these variables on the possible contribution of residues for reconstructing Late Pleistocene technologies. The results indicate that all these variables play a role in interpreting stone tool residues and should be considered crucial elements of a residue analysis protocol. • Residue analysis providied unique high-resolution details about Late Pleistocene stone tool hominin behaviour. • Residues linked with production, hafting, or tool use could be observed on the lithic assemblage of Grotta di Fumane. • Anthropogenic sedimentation is one of the primary sources for the environmental residue deposition. • A profound understanding of the burial context is crucial for interpreting stone tool residues. [ABSTRACT FROM AUTHOR]

DC hubs are centrally located in DC grids and they are expected to operate autonomously under wide range of operating conditions. To achieve secure operation without intervention from dispatcher and to damp the internal oscillatory modes, a distributed power balance and damping controller for high power multiport LCL (Inductor–Capacitor–Inductor) DC hub is proposed in this paper. Natural power balance mechanism of the hub is analyzed. To avoid over-voltage and over-power during un-balanced power orders, an actively controlled distributed power balance control for each port of the hub is proposed. As LCL circuit is used in the hub, there might exist prolonged oscillations in the hub. Small signal modelling and eigenvalue studies are used to identify the dominant oscillation mode of the hub. The participation factors are calculated to identify the state variables that best represent the dominant oscillation modes. The residue analysis is used to pair the feedback signals and design the structure of the damping controller. Robustness of the damping loop against topology changes is analyzed. Effectiveness of the designed controller in terms of secure operation and transient responses is verified by extensive PSCAD/EMTDC simulations on a 4-port test LCL DC hub. [ABSTRACT FROM AUTHOR]

The present research work is based on the degradation of benzoic acid (BA) and chemical oxygen demand (COD) from laboratory prepared aqueous solution. An electrocoagulation approach using aluminum (Al) and iron (Fe) as electrode material is applied in this study. A full factorial (4-factors, 5-level, and 3-response) rotatable central composite design in response surface methodology was developed for optimization of process parameters. Operating parameters such as pH (4–12), current density (A/m 2 )—(76.00–230.00), electrolysis time (min)—(15–90) and electrolyte concentration (NaCl) (g/L)—(0.5–1.5) are chosen for the study. Maximum % removal efficiency of BA—70.52, 64.42; COD—65.65, 60.70 and E. consumption (kWh/kgCOD removed )—102.89, 133.52 are achieved at optimal operating conditions by Al and Fe electrodes respectively. Sludge samples generated after EC treatment at optimum treatment conditions are also analyzed by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy, TGA/DTA (thermo gravimetric analysis and differential thermo gravimetric analysis, FTIR (Fourier transform infrared spectroscopy), XRD (X-ray diffraction). Settling characteristics of sludge samples are also studied for both Al and Fe electrodes. [ABSTRACT FROM AUTHOR]

Residues of antibiotics (ABs) in the aquatic environment and in food of animal origin represent a major concern, as prolonged exposure to ABs is a serious health hazard, related to both the side effects of prolonged use and the risk of developing bacterial resistance to various ABs. Given the low levels of the AB residues in complex matrices, the development of sensitive analytical methods represents a major challenge. This is certainly true for the aminoglycoside ABs (AGs) which lack a chromophore and show poor chromatographic properties in reversed-phase liquid chromatography. This paper reviews the current state of the art in the determination of AGs. Attention is paid to extraction, sample clean-up, chromatographic separation, and detection of AGs in both environmental and food samples and in plasma and serum. A general workflow for the analysis of AGs is presented which takes into account the matrix and required level of information. [ABSTRACT FROM AUTHOR]

This paper describes a highly sensitive analytical method using high-performance liquid chromatography and fluorescence detection (HPLC–FLD) capable of quantifying trace amounts of synthetic pyrethroid insecticide etofenprox residue in six vegetable samples: bell pepper, cucumber, eggplant, Japanese mustard spinach, spinach, and tomato. After extraction with acetonitrile, the crude sample extract was cleaned up with a solid-phase extraction cartridge. The matrix interference derived from the tested vegetable samples was evaluated. Quantification was conducted using external calibrators prepared in pure acetonitrile. The limits of quantification for etofenprox in each sample were 1.87–3.87 ng/g. Recoveries obtained by application of the proposed analytical method of vegetable samples spiked at the considerably low levels (5–100 ng/g) were 85–111% with relative standard deviations of less than 12%. The proposed method using the HPLC–FLD was applied for trace analysis of the insecticide residue in vegetable samples. [ABSTRACT FROM AUTHOR]

This paper examines a problem in enumerative and asymptotic combinatorics involving the classical structure of integer compositions. What is sought is an analysis on average and in distribution of the length of the longest run of consecutive equal parts in a composition of size n . The problem was posed by Herbert Wilf at the Analysis of Algorithms conference in July 2009 (see arXiv:0906.5196 ). [ABSTRACT FROM AUTHOR]

An innovative method for directly screening pesticide residues in foodstuffs was developed using ambient microfabricated glow discharge plasma (MFGDP) desorption/ionization mass spectrometry. The capability of qualitative and quantitative analysis with MFGDP–MS at atmospheric pressure on agrochemicals has been demonstrated. Nine multi-class compounds (ametryn, amitraz, buprofezin, dimethoate, diphenylamine, imazalil, isoproturon, malathion, parathion-ethyl) were examined in spiked solutions, in extracts of fruits and vegetables, and in unprocessed samples. In the standard solutions of the nine pesticides, the application of MFGDP-MS for the detection of organophosphorus, organochlorine and organonitrogen compounds was demonstrated. Limits of detection (LODs) at levels down to 0.13 ng g −1 mm −2 of the spiked extracts of tomato, green pepper, and orange (collected by “QuEChERS”) were obtained, with RSDs of 3.48–13.46%. In the direct analysis of unspiked peels and extracts of apple, celery and grapes, the residues of diphenylamine, dimethoate and malathion were successfully analyzed by tandem mass spectrometry (MS/MS). The distribution of diphenylamine in apples was obtained by scanning the various unprocessed parts of the apple piece-by-piece in depth directly. Thus, an MFGDP–MS, having a small size and operating at a low temperature, made it possible to directly and accurately screen for pesticide residues in fruits and vegetables in situ . [ABSTRACT FROM AUTHOR]

The chiral separation of haloxyfop enantiomers was first performed on (R, R) Whelk-O1 chiral column (pirkle type) by high-performance liquid chromatography (HPLC). Chromatographic conditions such as mobile phase composition and column temperature were optimized, and the best resolution was obtained using hexane/n-propanol (98/2) with Rs value of 3.43. Chiral residue analysis methods for haloxyfop enantiomers in environmental matrices, such as soil and water, were developed with recoveries ranging from 85.95% to 104.25%. The results showed that these methods were effective enough for detecting the residual enantiomers environmental matrices. The behavior of haloxyfop in four soils was studied and the enantioselective degradation was found with enantiomer fraction values ranging from 0.058 to 0.61. The research work was extremely useful for investigating the fate of individual enantiomers in environment, the mechanism of the stereoselective behaviors, and the risk assessment of chiral pesticide. [ABSTRACT FROM AUTHOR]

Fourier transform infrared spectroscopy (FT-IR) is a versatile analytical method, very useful in many fields. Although a crucial step in producing good spectra is the use of the appropriate technique, the acquisition mode is sometimes not accurately selected and the results are partial or lacking. In recent years, FT-IR analysis has been proposed as a screening method for characterization of archaeological potteries and identification of the residues on these artifacts before turning to destructive, more expensive, and time-consuming techniques. In this study, a set of pottery shards, classified as fragments of amphorae, was subjected to FT-IR analyses. The results obtained from different sampling procedures and different spectra acquisition modes, were examined and compared. The as-received ceramic fragments were subjected to micro attenuated total reflectance (μ-ATR) analyses. Investigations in diffuse reflectance (DRIFT) mode were performed on samples collected by abrading the surfaces of the shards with abrasive paper. Samples scraped from either the surfaces of the pottery fragments or the interior of the ceramic body, were analyzed in transmission mode as a powder in KBr pellets or after extraction with acetone. The sampling by abrasion of the surface with an abrasive disk, and consequently the analyses in DRIFT mode, were successful only in identifying the inorganic compounds coming from the pottery and/or the environment, while materials related to the content of the jar were not detected. Also the analyses in transmission mode provided information mainly about inorganic materials, which, even where in a limited amount, masked the signals of organic compounds. Just an extraction with a solvent made it possible a more detailed, but still partial, characterization of these organic substances. On the contrary, the content of the jar was easily detected using the μ-ATR mode, even in areas where no residue was observed. [ABSTRACT FROM AUTHOR]

[Display omitted] • D-limonene and its oxidation products residues were determined in vegetables and soils by using QuEChERS and GC–MS method. • D-limonene and its oxidation products were not persistent in soil. • Degradation of d -limonene in soil was dominated by aerobic microorganisms. A simple, rapid and effective gas chromatography–mass spectrometry method was developed for the simultaneous determination of d-limonene and its oxidation products in some vegetables and soils. Using the quick, easy, cheap, effective, rugged and safe (QuEChERS) method, the sample was extracted with n-hexane, purified with octadecylsilane (C18) and graphitized carbon black (GCB), and detected using gas chromatography-quadrupole mass spectrometry. The linear correlation coefficients of all analytes in the nine matrices were good (R2 > 0.995). At levels of 50, 100, and 1000 μg kg−1, the average recoveries ranged from 71.2 to 114.5%, while intra-day and inter-day precision were below 13.4%. The limits of detection (LODs) and the limits of quantification (LOQs) in all matrices for d-limonene and its five oxidation products were 1–16 and 4–48 μg kg−1, respectively. The residual levels of d-limonene can be well described by first-order kinetics. Dissipation in soil was microbially dominated, with half-lives of 1.95–2.84 days in the three soils and no residue in tomatoes. Its oxidation products were converted in soil mainly by microorganisms, with more trans -isomer production compared to cis -isomer. Moreover, no d-limonene residue was detected in tomatoes, and the persistence of d-limonene in soil was limited. The results of this study can provide data to understand the fate of d-limonene in tomato and soil and for further study its suitability as an environmentally friendly agrochemical. [ABSTRACT FROM AUTHOR]

The coupling of ultra-high-performance liquid chromatography (UHPLC) with high-resolution mass spectrometry (HRMS) has been well received within the analytical community. Both technologies have experienced significant advances in recent years. Not only have the resolution power and sensitivity improved, but the increased robustness, which includes prolonged column lifetime, extended dynamic range, easier mass calibration, and enhanced software handling capabilities, is making this coupling more attractive to a larger user base. In this article, we discuss possibilities and current limitations of the UHPLC-HRMS coupling. We also review the application of UHPLC-HRMS in a variety of fields, where it has been widely accepted or where we anticipate more extensive use in the near future. [ABSTRACT FROM AUTHOR]

Starch grains, phytoliths and plant tissue fragments from Upper Paleolithic stone artifacts provide direct evidence of plant use activities in Northwest China during late MIS 3. These results demonstrate the considerable role of edible plants during the last glacial epoch. The chosen plant species can also help us understand the development of human plant exploitation, for which we have limited knowledge for the Paleolithic. This research also suggests the survival and adaptation patterns of ancient occupants in this cold and dry highland area of East Asia during the Upper Paleolithic. [ABSTRACT FROM AUTHOR]

Highlights: [•] MEQ, QCT, and their 11 major metabolites are firstly simultaneously detected. [•] UPLC equipment is applied for the determination with high detection efficiency. [•] MS/MS equipment exhibited high responses with low LODs for trace analysis. [ABSTRACT FROM AUTHOR]

Highlights: [•] A new UPLC–MS/MS method was developed for the quantification of illegal dyes in fish tissues. [•] Due to the presence of strong positively charged sulphur groups, attention was paid to the solid phase elution step. [•] The validation was performed according to standards of European Union (Directive 2002/657/EC) and scientific literature. [•] The method was able to quantify at 0.25ngg−1. [•] Applicability of the method was shown in a subsequent monitoring study of wildlife eel in Flemish rivers. [ABSTRACT FROM AUTHOR]

Abstract: Neanderthal behavior is often described in one of two contradictory ways: 1) Neanderthals were behaviorally inflexible and specialized in large game hunting or 2) Neanderthals exhibited a wide range of behaviors and exploited a wide range of resources including plants and small, fast game. Using stone tool residue analysis with supporting information from zooarchaeology, we provide evidence that at the Abri du Maras, Ardèche, France, Neanderthals were behaviorally flexible at the beginning of MIS 4. Here, Neanderthals exploited a wide range of resources including large mammals, fish, ducks, raptors, rabbits, mushrooms, plants, and wood. Twisted fibers on stone tools provide evidence of making string or cordage. Using a variety of lines of evidence, we show the presence of stone projectile tips, possibly used in complex projectile technology. This evidence shows a level of behavioral variability that is often denied to Neanderthals. Furthermore, it sheds light on perishable materials and resources that are not often recovered which should be considered more fully in reconstructions of Neanderthal behavior. [Copyright &y& Elsevier]

Highlights: [•] Optimization of solid-phase extraction for biocidal oligoguanidines from water samples. [•] Quantitation by liquid chromatography hyphenated with mass spectrometry. [•] Detection limits in the sub-μgL−1 range allow residue analysis in the environment. [•] Selection of appropriate markers for complex mixtures of oligoguanidines. [Copyright &y& Elsevier]