scholarly journals Simultaneous Screening and Target Analytical Approach by Gas Chromatography-Quadrupole-Mass Spectrometry for Pesticide Residues in Fruits and Vegetables

2009 ◽  
Vol 92 (6) ◽  
pp. 1790-1806 ◽  
Author(s):  
Milagros Mezcua ◽  
Maria A Martínez-uroz ◽  
Philip L Wylie ◽  
Amadeo R fernández-alba
Keyword(s):  
Large Scale ◽  
Proficiency Test ◽  
Fruits And Vegetables ◽  
Screening Method ◽  
Correlation Coefficients ◽  
Food Samples ◽  
Identification Performance ◽  
Data Files ◽  
Full Scan ◽  
Scan Data

Abstract A full-scan GC/quadrupole/MS method has been developed to perform large-scale screenings of pesticides and simultaneous quantification of 95 target compounds in a single run of 21 min. The screening method was performed by using a deconvolution of the spectrum of the full-scan data files acquired under a retention time locked method. The identification performance of the screening method was evaluated in eight different food matrixes at three different concentrations. The system was equipped with a programmable temperature vaporizing inlet, allowing 10 L injections. The LOQ in the full-scan mode and linearity were studied for four different matrixes. Correlation coefficients >0.99 were achieved in all cases, and the LOD was <20 g/kg for 80 of the studied pesticides. Maintenance of the system was reduced by the use of a QuickSwap device that provided backflush capabilities by reversing column flow immediately after elution of the last compound of interest. The combined screening and target method was used in the analysis of more than 100 food samples, including a carrot sample from the European Proficiency Test FV 10, with good results.

Pesticide Residue Analysis in Fruit- and Vegetable-Based Baby Foods Using GC-Orbitrap MS

2018 ◽  
Vol 101 (2) ◽  
pp. 374-382 ◽  
Author(s):  
Ana Lozano ◽  
Samanta Uclés ◽  
Ana Uclés ◽  
Carmen Ferrer ◽  
Amadeo R Fernández-Alba
Keyword(s):  
Proficiency Test ◽  
Residue Analysis ◽  
Food Samples ◽  
Baby Food ◽  
The European Union ◽  
Baby Foods ◽  
Z Scores ◽  
Full Scan ◽  
Multiresidue Pesticide Analysis ◽  
Orbitrap Ms

Abstract This paper presents an efficiency evaluation of GC coupled with quadrupole Orbitrap MS for identification and quantitation in the multiresidue pesticide analysis of baby foods in full-scan mode. The identification criteria were studied following SANTE guidelines (retention time, mass accuracy, and ion ratio), comfortably complying with the values established, even at 0.003 mg/kg. Method validation was carried out on 15 selected GC-amenable pesticides covered by Commission Directive No. 2006/125/EC in three different baby food matrixes. Recovery studies were performed at 0.003 and 0.006 mg/kg, with 96% of the cases falling within the 70–120% range and with RSDs <15% for all the pesticides assayed. Linearity over 3 orders of magnitude was verified, with residuals <16% and correlation coefficient values >0.995. In general, matrix effect values were >100%. The LOQ was 0.003 mg/kg for 97% of the cases. The validated method was applied to 20 real baby food samples from Spain and to the European Union Proficiency Test FV-BF01 sample, in which the z-scores obtained were <1, thus demonstrating that this instrumentation has good quantitation capabilities.

Detection of 20 Phthalate Esters in Different Kinds of Food Packaging Materials by GC-MS/MS with Five Internal Standards

2019 ◽  
Vol 102 (1) ◽  
pp. 255-261 ◽  
Author(s):  
Ji-cai Fan ◽  
Quan Jin ◽  
Hua-li He ◽  
Ren Ren ◽  
Shu-ting Wang
Keyword(s):  
Food Packaging ◽  
Large Scale ◽  
Phthalate Esters ◽  
Correlation Coefficients ◽  
Packaging Materials ◽  
Purification Step ◽  
Internal Standards ◽  
Extraction Solvent ◽  
Food Packaging Materials ◽  
Relative Standard

Abstract Background: Phthalate esters (PAEs) are a group of chemical compounds widely used as plasticizers to increase the flexibility of plastics that are used in the manufacturing of kitchen utensils and food containers. Objective: In this study, a simple, rapid, and sensitive method for the determination of 20 PAEs in different kinds of food packaging materials has been developed. Methods: Samples injected with five internal standards were extracted with acetonitrile saturated with n-hexane and then detected by GC-MS/MS without a purification step. Results: The standard calibration curves were linear for all analytes over the concentration range of 5–500 μg/L, and the correlation coefficients ranged from 0.9913 to 0.9999. The LODs and LOQs were in the ranges of 1.7–62.5 and 5.5–208.3 μg/kg, respectively. The accuracy of this method was evaluated by measuring the recovery from spiked samples. The recoveries of all 20 phthalates from samples spiked at three different concentrations were measured, and the recovery was in the range of 82.1–110.8% and the relative standard deviation range of recovery result (n = 6) was 0.3–9.7%. Conclusions: The method presented here is simple, rapid, and sensitive and can be applied to large-scale detection of PAEs in plastic materials. Highlights: Instead of only one solvent, acetonitrile saturated with n-hexane was used as the extraction solvent. Samples were pretreated without a purification step. Five internal standards were used for quantitative determination.

scholarly journals Cross-Scale Precipitation Variability in a Semiarid Catchment Area on the Western Slopes of the Central Andes

2018 ◽  
Vol 57 (3) ◽  
pp. 675-694 ◽  
Author(s):  
Katja Trachte ◽  
Jochen Seidel ◽  
Rafael Figueroa ◽  
Marco Otto ◽  
Joerg Bendix
Keyword(s):  
Cluster Analysis ◽  
Catchment Area ◽  
Altitudinal Gradient ◽  
Large Scale ◽  
Wrf Model ◽  
Correlation Coefficients ◽  
Elevational Gradient ◽  
Central Andes ◽  
Precipitation Variability ◽  
Precipitation Regimes

AbstractSpatiotemporal precipitation patterns were investigated on the western slopes of the central Andes Mountains by applying EOF and cluster analysis as well as the Weather Research and Forecasting (WRF) Model. In the semiarid catchment area in the highlands of Lima, Peru, the precipitation is assumed to be a cross-scale interplay of large-scale dynamics, varying sea surface temperatures (SSTs), and breeze-dominated slope flows. The EOF analysis was used to encompass and elucidate the upper-level circulation patterns dominating the transport of moisture. To delineate local precipitation regimes, a partitioning cluster analysis was carried out, which additionally should illustrate local effects such as the altitudinal gradient of the Andes. The results demonstrated that especially during the transition to the dry season, synoptic-scale circulation aloft controls the precipitation (correlation coefficients between 0.6 and 0.9), whereas in the remaining seasons the slope breezes due to the altitudinal gradient mainly determine the precipitation behavior. Further analysis with regard to the spatiotemporal precipitation variability revealed an inversion of the precipitation distribution along the elevational gradient within the study area, mainly during February (29%) and March (35%), that showed correlations with coastal SST patterns ranging between 0.56 and 0.67. WRF simulations of the underlying mechanisms disclosed that the large-scale circulation influences the thermally induced upslope flows while the strength of southeastern low-level winds related to the coastal SSTs caused a blocking of easterlies in the middle troposphere through a reduced anticyclonic effect. This interplay enables the generation of precipitation in the usually drier environment at lower elevations, which leads to a decrease in rainfall with increasing elevation.

Collaborative firms managing perishable products in a complex supply network: an empirical analysis of performance

2015 ◽  
Vol 20 (2) ◽  
pp. 128-138 ◽  
Author(s):  
Juan Carlos Pérez Mesa ◽  
Emilio Galdeano-Gómez
Keyword(s):  
Supply Chain ◽  
Large Scale ◽  
Fruits And Vegetables ◽  
Perishable Products ◽  
Supply Network ◽  
Content Type ◽  
Sales Channels ◽  
Positive Effects ◽  
Starting Point ◽  
Supplier Relationship

Purpose – This purpose of this study is to provide empirical evidence of how cooperation is related to suppliers’ performance, a relationship that is thought to be affected by the type of customer and the extent to which the market is diversified. It analyzes horticultural exporting firms in southeastern Spain, which are the main suppliers of European markets. Together with their primary customers (large-scale retail companies such as Carrefour, Tesco and Aldi), these firms constitute a complex supply network composed of a variety of agents and sales channels. This network will be studied from the perspective of the supplier–supplier relationship that is critical to their survival. Design/methodology/approach – Starting with a detailed description of Europe’s vegetable supply chain, a hierarchical regression is used with an index of cooperation intensity, moderated by retail sales and market concentration. The authors test the hypotheses using panel data on a set of 118 horticultural marketing firms in southeast Spain for the period 2009-2011. Findings – Cooperation strategies are shown to have positive effects on performance (market creation, promotion, quality, training, joint supply purchases and research ventures). Moreover, the retail channel and market diversification are observed to have a positive effect on the relationship between cooperation and the supplier’s performance. They demonstrate that active cooperation strategies have a greater bearing on performance in those firms whose primary customers are retailers. This circumstance provides evidence of the synergies and benefits that may arise when the supplier integrates the retailer in the supply chain, but which do not arise with other types of customers. Research limitations/implications – Although this study refers to a specific sector (fruits and vegetables) and the statistical results are limited, they provide insights that may assist in understanding how other perishable produce-related industries work: such industries share many common features. Practical implications – A more stable relationship between suppliers and retailers in the perishable produce market will render the supply firm more cooperative, competitive and profitable. Increased performance does not arise from the better conditions and improved sales power offered by the customer but instead from the adaptability of the supplier. Likewise, market diversification drives the supply firm toward a cooperative strategy, making it more profitable and competitive. As a practical norm, market diversification alone will not have positive results on performance unless the firm proves capable of enhancing its capacity for cooperation. Social implications – Proper management of the agricultural produce supply chain has repercussions on all of the members of that chain, although special emphasis should be placed on producers and consumers. The availability of food, its quality and its safety depend on management during the production phase. Along these lines, and more specifically for the consumer, this work is relevant because the sector analyzed accounts for 40 per cent of the vegetables consumed in Europe. Originality/value – This article defends the supplier–supplier relationship as the starting point for the analysis of a supply network. In certain sectors, the suppliers’ ability both to solve their clients’ problems and to be profitable is conditioned on maintaining the network and, therefore, the basic focus must center on analyzing their relationships, always including the customer, who has a direct or indirect influence on those relationships. Previous research has not comprehensively addressed this issue, let alone that of a sector with agile and perishable products in which, due to its nature, decision-making about market destinations and sales channels is the order of the day.

Extended Geometric Filter for Reconstruction as a Basis for Computational Inspection

2009 ◽  
Vol 131 (5) ◽  
Author(s):  
Alexander Miropolsky ◽  
Anath Fischer
Keyword(s):  
Quality Control ◽  
Computer Model ◽  
Large Scale ◽  
Manufacturing Industry ◽  
Digital Design ◽  
Reconstruction Methods ◽  
Object Based ◽  
Inspection Process ◽  
Important Quality ◽  
Scan Data

The inspection of machined objects is one of the most important quality control tasks in the manufacturing industry. Contemporary scanning technologies have provided the impetus for the development of computational inspection methods, where the computer model of the manufactured object is reconstructed from the scan data, and then verified against its digital design model. Scan data, however, are typically very large scale (i.e., many points), unorganized, noisy, and incomplete. Therefore, reconstruction is problematic. To overcome the above problems the reconstruction methods may exploit diverse feature data, that is, diverse information about the properties of the scanned object. Based on this concept, the paper proposes a new method for denoising and reduction in scan data by extended geometric filter. The proposed method is applied directly on the scanned points and is automatic, fast, and straightforward to implement. The paper demonstrates the integration of the proposed method into the framework of the computational inspection process.

scholarly journals Deletion of two genes improves heterologous secretion of fungal lignin-degrading heme peroxidases in S. cerevisiae

2021 ◽  
Author(s):  
Nikita A. Khlystov
Keyword(s):  
Large Scale ◽  
Screening Method ◽  
Strain Engineering ◽  
Scale Production ◽  
Heterologous Production ◽  
Yeast Saccharomyces Cerevisiae ◽  
Double Deletion ◽  
Large Scale Production ◽  
Crucial Component ◽  
Heme Peroxidases

Efficient, large-scale heterologous production of enzymes is a crucial component of the biomass valorization industry. Whereas cellulose utilization has been successful in applications such as bioethanol, its counterpart lignin remains significantly underutilized despite being an abundant potential source of aromatic commodity chemicals. Fungal lignin-degrading heme peroxidases are thought to be the major agents responsible for lignin depolymerization in nature, but their large-scale production remains inaccessible due to the genetic intractability of basidiomycete fungi and the challenges in the heterologous production of these enzymes. In this study, we employ a strain engineering approach based on functional genomics to identify mutants of the model yeast Saccharomyces cerevisiae with enhanced heterologous production of lignin-degrading heme peroxidases. We show that our screening method coupling an activity-based readout with fluorescence-assisted cell sorting enables identification of two single null mutants of S. cerevisiae, pmt2 and cyt2, with up to 11-fold improved secretion of a versatile peroxidase from the lignin-degrading fungus Pleurotus eryngii. We demonstrate that the double deletion strain pmt2cyt2 displays positive epistasis, improving and even enabling production of members from all three classes of lignin-degrading fungal peroxidases. We anticipate that these mutant strains will be broadly applicable for improved heterologous production of this biotechnologically important class of enzymes.

scholarly journals Architecture of Sample Preparation and Data Governance of Immuno-Genomic Data Collected from Bone Marrow and Peripheral Blood Samples Obtained from Multiple Myeloma Patients

Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 17-18
Author(s):  
Shaadi Mehr ◽  
Daniel Auclair ◽  
Mark Hamilton ◽  
Leon Rozenblit ◽  
Hearn Jay Cho ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Bone Marrow ◽  
Board Of Directors ◽  
Peripheral Blood ◽  
Large Scale ◽  
Mass Cytometry ◽  
Data Governance ◽  
Advisory Committees ◽  
Blood Samples ◽  
Data Files

Abstract: Title: Architecture of sample preparation and data governance of Immuno-genomic data collected from bone marrow and peripheral blood samples obtained from multiple myeloma patients In multiple myeloma (MM), the interactions between malignant plasma cells and the bone marrow microenvironment is crucial to fully understand tumor development, disease progression, and response to therapy. The core challenge in understanding those interactions has been the establishment of a standard process and a standard model for handling the data quality workflow and the underlying data models. Here we present the Platform (Figure 1), an integrated data flow architecture designed to create data inventory and process tracking protocols for multi-dimensional and multi-technology immune data files. This system has been designed to inventory and track peripheral blood and bone marrow samples from multiple myeloma subjects submitted for immune analysis under the MMRF Immune Atlas initiative (figure 2), and the processing and storage of Single Cell RNA-seq (scRNA-seq) and Mass Cytometry time-of-flight (CyTOF) data files derived from these immune analyses. While these methods have been previously applied on both tumor and immune populations in MM [2,3], this level of multi-institutional and multi-technology is unique. The Cloud Immune-Precision platform contains standardized protocols and bioinformatics workflows for the identification and categorization of immune cell populations and functional states based upon scRNA-seq gene signatures (ref: Bioinformatics manuscript in submission) and CyTOF protein signatures. Upon further expansion, it will contain high dimensional scRNAseq and CyTOF immune data from both bone marrow and peripheral blood samples from myeloma patients enrolled in the Multiple Myeloma Research Foundation (MMRF) CoMMpass study (NCT01454297) [1] (Figure 3). The architecture covers the automation of data governance protocols, data transformation and ETL model developments that will create an immune proteomic and profiling database and its integration into clinical and genomics databases: e.g. the MMRF CoMMpass clinical trial. This large-scale data integration will establish a cutting-edge Immune-Precision central platform supporting large scale, immune-focused advanced analytics in multiple myeloma patients. This platform will allow researchers to interrogate the relationships between immune transcriptomic and proteomic signatures and tumor genomic features, and their impact on clinical outcomes, to aid in the optimization of therapy and therapeutic sequencing. Furthermore, this platform also promotes the potential to (further) elucidate the mechanisms-of-action of approved and experimental myeloma therapies, drive biomarker discovery, and identify new targets for drug discovery. Figure 1: Cloud Immune-Precision Platform (Integrated data flow architecture designed to create data inventory and process tracking protocols for multi-dimensional and multi-technology immune data files) Figure 2: Sample tracking process architecture Figure 3: Data file creation and repository process tracking References: 1- Settino, Marzia et al. "MMRF-CoMMpass Data Integration and Analysis for Identifying Prognostic Markers." Computational Science - ICCS 2020: 20th International Conference, Amsterdam, The Netherlands, June 3-5, 2020, Proceedings, Part III vol. 12139 564-571. 22 May. 2020, doi:10.1007/978-3-030-50420-5_42 2- Ledergor, Guy et al. "Single cell dissection of plasma cell heterogeneity in symptomatic and asymptomatic myeloma." Nature medicine vol. 24,12 (2018): 1867-1876. doi:10.1038/s41591-018-0269-2 3- Hansmann, Leo et al. "Mass cytometry analysis shows that a novel memory phenotype B cell is expanded in multiple myeloma." Cancer immunology research vol. 3,6 (2015): 650-60. doi:10.1158/2326-6066.CIR-14-0236-T Figure 1 Disclosures Bhasin: Canomiiks Inc: Current equity holder in private company, Other: Co-Founder. Dhodapkar:Amgen: Membership on an entity's Board of Directors or advisory committees, Other; Celgene/BMS: Membership on an entity's Board of Directors or advisory committees, Other; Janssen: Membership on an entity's Board of Directors or advisory committees, Other; Roche/Genentech: Membership on an entity's Board of Directors or advisory committees, Other; Lava Therapeutics: Membership on an entity's Board of Directors or advisory committees, Other; Kite: Membership on an entity's Board of Directors or advisory committees, Other.

scholarly journals Smallholder Farmers’ Challenges of Coping with COVID-19 Containments: Insights from two food regions in Indonesia

2021 ◽  
Vol 21 (06) ◽  
pp. 18223-18244
Author(s):  
Silke Stöber ◽  
◽  
K Adinata ◽  
T Ramba ◽  
N Paganini ◽  
...  
Keyword(s):  
Food Security ◽  
Large Scale ◽  
Fruits And Vegetables ◽  
Smallholder Farmers ◽  
Observational Research ◽  
Food Groups ◽  
Social Distancing ◽  
Limited Mobility ◽  
Female Farmers ◽  
Price Spikes

The COVID-19 pandemic has forced governments around the world to impose containment measures to prevent the rapid spread of the corona virus. The Indonesian government implemented “large-scale social restrictions,” which have impacted farming and farmers’ food security. Farmers are both producers and consumers of food and, therefore, have been facing new challenges due to transport restrictions, price spikes for inputs, price drops for their produce, or conditions which aggravated cooperation, such as social distancing. This study aims at analysing the challenges of the containments from a smallholder farmer perspective and examining farmers’ coping potential. A digital survey with 323 farmers has been designed as comparative observational research in Toraja, South Sulawesi, and selected regions of Java. The Bonferroni Multiple Comparison Test was used to test for significance regarding socio-economic factors and space. A logistic regression model extracted determinants for crisis coping. Results reveal, that female farmers worry more about COVID-19 outbreak compared to men at a significant level. In contrast, male farmers, particularly in Java, are more concerned about social restrictions due to limited mobility. Food price spikes were reported in both regions, with sharp increases for fish, fruits, and vegetables in Java, for staples in Toraja, and for meat and sugar in both regions. Food groups, that trade through agents and brokers or are transported longer distances were affected most due to their complex and long supply chains that were disrupted during the restrictions. In Java, farmers face multiple shocks, of which climate change was reported even more often than the pandemic related shocks. Not being able to help each other on the farm due to social distancing is a significant concern of farmers in Toraja. As a result of food market disturbances, farmers began to grow and eat more vegetables and fruits. In conclusion, food security for farmers slightly decreased due to affordability, and market disruptions already point to long-term income losses. The study team recommends to promote smallholders’ healthy food production, value addition and direct end-consumer linkages to build back better their livelihoods post-COVID-19.

Investigation of ambient noise seismological methods on a bridge model

2021 ◽  
Author(s):  
Chun-Man Liao ◽  
Franziska Mehrkens ◽  
Celine Hadziioannou ◽  
Ernst Niederleithinger
Keyword(s):  
Wave Propagation ◽  
Large Scale ◽  
Seismic Velocity ◽  
Measurement Data ◽  
Correlation Coefficients ◽  
Coda Wave ◽  
Velocity Change ◽  
Promising Tool ◽  
Bridge Model ◽  
Noise Measurements

<p>The aim of this work is to investigate the application of seismological noise-based monitoring for bridge structures. A large-scale two-span concrete bridge model with a build-in post-tensioning system, which is exposed to environmental conditions, is chosen as our experimental test structure. Ambient seismic noise measurements were carried out under different pre-stressed conditions. Using the seismic interferometry technique, which is applied to the measurement data in the frequency domain, we reconstruct waveforms that relate to wave propagation in the structure. The coda wave interferometry technique is then implemented by comparing two waveforms recorded in two pre-stress states. Any relative seismic velocity changes are identified by determining the correlation coefficients and reveal the influence of the pre-stressing force. The decrease of the wave propagation velocity indicates the loss of the pre-stress and weakening stiffness due to opening or event extension of cracks. We conclude that the seismological methods used to estimate velocity change can be a promising tool for structural health monitoring of civil structures.</p>

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