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2022 ◽  
Vol 27 (1) ◽  
pp. 1-25
Author(s):  
Qiang Liu ◽  
Honghui Tang ◽  
Peiran Zhang

Fault injection attack (FIA) has become a serious threat to the confidentiality and fault tolerance of integrated circuits (ICs). Circuit designers need an effective method to evaluate the countermeasures of the IC designs against the FIAs at the design stage. To address the need, this article, based on FPGA emulation, proposes an in-circuit early evaluation framework, in which FIAs are emulated with parameterized fault models. To mimic FIAs, an efficient scan approach is proposed to inject faults at any time at any circuit nodes, while both the time and area overhead of fault injection are reduced. After the circuit design under test (CUT) is submitted to the framework, the scan chains insertion, fault generation, and fault injection are executed automatically, and the evaluation result of the CUT is generated, making the evaluation a transparent process to the designers. Based on the framework, the confidentiality and fault-tolerance evaluations are demonstrated with an information-based evaluation approach. Experiment results on a set of ISCAS89 benchmark circuits show that on average, our approach reduces the area overhead by 41.08% compared with the full scan approach and by over 20.00% compared with existing approaches. The confidentiality evaluation experiments on AES-128 and DES-56 and the fault-tolerance evaluation experiments on two CNN circuits, a RISC-V core, a Cordic core, and the float point arithmetic units show the effectiveness of the proposed framework.


Toxins ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 823
Author(s):  
Mirjam D. Klijnstra ◽  
Elisabeth J. Faassen ◽  
Arjen Gerssen

Phycotoxins occur in various marine and freshwater environments, and can accumulate in edible species such as fish, crabs, and shellfish. Human exposure to these toxins can take place, for instance, through consumption of contaminated species or supplements and through the ingestion of contaminated water. Symptoms of phycotoxin intoxication include paralysis, diarrhea, and amnesia. When the cause of an intoxication cannot directly be found, a screening method is required to identify the causative toxin. In this work, such a screening method was developed and validated for marine and freshwater phycotoxins in different matrices: fish, shellfish, water, and food supplements. Two LC methods were developed: one for hydrophilic and one for lipophilic phycotoxins. Sample extracts were measured in full scan mode with an Orbitrap high resolution mass spectrometer. Additionally, a database was created to process the data. The method was successfully validated for most matrices, and in addition, regulated lipophilic phycotoxins, domoic acid, and some paralytic shellfish poisoning toxins could be quantified in shellfish. The method showed limitations for hydrophilic phycotoxins in sea water and for lipophilic phycotoxins in food supplements. The developed method is a screening method; in order to confirm suspected compounds, comparison with a standard or an additional analysis such as NMR is required.


Foods ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 2473
Author(s):  
Meng-Lei Xu ◽  
Yu Gao ◽  
Xiao Wang ◽  
Xiao Xia Han ◽  
Bing Zhao

Food safety and quality have been gaining increasing attention in recent years. Gas chromatography coupled to tandem mass spectrometry (GC–MS/MS), a highly sensitive technique, is gradually being preferred to GC–MS in food safety laboratories since it provides a greater degree of separation on contaminants. In the analysis of food contaminants, sample preparation steps are crucial. The extraction of multiple target analytes simultaneously has become a new trend. Thus, multi-residue analytical methods, such as QuEChERs and adsorption extraction, are fast, simple, cheap, effective, robust, and safe. The number of microorganic contaminants has been increasing worldwide in recent years and are considered contaminants of emerging concern. High separation in MS/MS might be, in certain cases, favored to sample preparation selectivity. The ideal sample extraction procedure and purification method should take into account the contaminants of interest. Moreover, these methods should cooperate with high-resolution MS, and other sensitive full scan MSs that can produce a more comprehensive detection of contaminants in foods. In this review, we discuss the most recent trends in preparation methods for highly effective detection and analysis of food contaminants, which can be considered tools in the control of food quality and safety.


Insects ◽  
2021 ◽  
Vol 12 (10) ◽  
pp. 886
Author(s):  
Olle Anderbrant ◽  
D. Barry Lyons ◽  
Joakim Bång ◽  
Erik Hedenström ◽  
Hans-Erik Högberg

Extracts of Diprion similis females contained about 15 ng of the sex pheromone precursor 3,7-dimethylpentadecan-2-ol per female. After derivatisation with (S)-2-acetoxypropanoyl chloride, we found that the major stereoisomer in the extract was (2S,3R,7R)-3,7-dimethylpentadecan-2-ol. Small amounts of other stereoisomers of 3,7-dimethylpentadecan-2-ol were also identified in the extract, namely 1% of (2R,3S,7S), 0.3% (2R,3R,7R) and 0.4% of (2R,3R,7S). An unknown fifth substance showed a very similar spectrum to 3,7-dimethylpentadecan-2-ol, both in SIM and full scan mode. None of the earlier suggested behavioural synergistic isomers ((2S,3S,7S), (2S,3S,7R) and (2S,3R,7S)) were detected in the extracts. In field tests in Ontario, Canada, the earlier identified main pheromone component, viz. the propanoate of (2S,3R,7R)-3,7-dimethylpentadecan-2-ol, was tested alone and in combination with other stereoisomers, earlier reported to be synergistic. No synergistic effects were detected and the threo four-isomer blend was as attractive as the pure main compound. Thus, one of the few examples of a diprionid sawfly using more than one substance in its sex pheromone could not be confirmed. The results also suggest that monitoring programs can use the more easily synthesized threo-blend without losing efficiency. Furthermore, the study suggests that other diprionid pheromones may benefit from a reinvestigation, to clarify possible synergistic effects of stereoisomers.


2021 ◽  
Vol 72 (3) ◽  
pp. 198-204
Author(s):  
Davorka Sutlović ◽  
Sendi Kuret ◽  
Marija Definis

Abstract We believe that analysing pooled urine samples for recreational drugs used at mass events can provide useful information about trends in drug use. An opportunity arose with the Ultra Europe music festival, which is attended by more than 150,000 people from over 150 countries every year. We analysed 30 pooled urine samples collected from portable chemical toilets located at or close to the Ultra Europe music festival venue in Split, Croatia in 2016–2018 to detect the presence of classic and new psychoactive substances (NPS). Four urine samples collected in 2016 were from a toilet without added chemicals (otherwise used to kill the smell) while the remaining samples were collected from toilets with added chemicals. Samples were qualitatively analysed with gas chromatography-mass spectrometry (GC/MS) using the full-scan mode. Data were compared with the Wiley mass spectral library of designer drugs and our in-house library containing about 1000 compounds and metabolites. We identified forty-six different substances and metabolites, 26 of which were classic substances/metabolites, mostly from the stimulants group, while 20 were NPS. In the NPS group, most of them were phenethylamines and cathinones. The variety of substances was the highest on the first day of the festival regardless of the year, but 2018 showed a significant drop compared to the previous two years. The results of our study revealed a stable trend of classic drug consumption, while NPS trend changed from one year to another.


2021 ◽  
Author(s):  
Vijay Laxmi Mohanta ◽  
Brijesh Kumar Mishra

Abstract Disinfection is an essential step to keep humans healthy from microorganisms present in drinking water. However, the formation of disinfection by-products (DBPs) is associated with adverse health effects, and the presence of organic pollutants in groundwater results in even more detrimental effects. Therefore, a better treatment technique is required to disinfect and remove organic pollutants simultaneously to control the formation of DBPs. Electro-chlorination (EC) was carried out using graphite electrode at the current density of 0.54–1.09 mA/cm2 and sodium chloride for in-situ hypochlorite generation to treat groundwater contaminated with phenol and aniline. The comparative study between chlorination and EC showed a significant level of oxidation of phenol and aniline, resulting in their reduction up to 98.48% and 99.47%, respectively, in the EC process. Due to the higher mineralization rate of aniline, both chlorination and EC method are found to be effective. However, only the EC method is found to be appropriate and effective for treating phenol-contaminated water as the chlorination method resulted in the formation of complicated phenolic by-products. Gas-Chromatography/Mass-Spectrometry (GCMS) was used to assess the by-product formation of chlorination and EC in contaminated groundwater through the full-scan.


Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 4000
Author(s):  
Lulu Xu ◽  
Zhanpeng Shang ◽  
Yungang Tian ◽  
Ming Xiong ◽  
Dilaram Nijat ◽  
...  

Shengmaisan (SMS) is a famous traditional Chinese medicine (TCM) formula to treat coronary heart diseases. It has been developed into several TCM patent drugs to meet the demands of different patients. In this study, a research strategy was proposed to reveal the chemical variations among four SMS-based patent drugs, including Shengmai Oral Solution (Shengmaiyin, SMY), Shengmai Capsule (Shengmai Jiaonang, SMJN), Yiqi Fumai Injection (YQFMI), and Yiqi Fumai Capsule (Yiqi Fumai Jiaonang, YQJN). Firstly, 227 compounds were tentatively identified using an Orbitrap-MS in the full scan/dd-MS2 mode. Secondly, untargeted metabolomics analysis suggested that ginsenosides, steroidal saponins, and lignans were the main types of differential compounds for the four patent drugs. Finally, the contents of 25 compounds were simultaneously determined in 30 batches of samples in the parallel reaction monitoring (PRM) mode. Partial least squares discriminant analysis (PLS-DA) revealed the contents of ginsenosides Re, Rg1, Rb1, Ro, and Rg3, and schisandrin showed the highest intergroup variations. These compounds were chemical markers to differentiate the SMS-based patent drugs.


2021 ◽  
Author(s):  
Zuzana Vankova ◽  
Ondrej Peterka ◽  
Michaea Chocholouskova ◽  
Robert Jirasko ◽  
Denise Wolrab ◽  
...  

Reversed-phase ultrahigh-performance liquid chromatography - mass spectrometry (RP-UHPLC/MS) method was developed with the aim to unambiguously identify a large number of lipid species from multiple lipid classes in human plasma. The optimized RP-UHPLC/MS method employed the C18 column with sub-2 micrometer particles with the total run time of 25 min. The chromatographic resolution was investigated with 42 standards from 18 lipid classes. The UHPLC system was coupled to high-resolution quadrupole - time-of-flight (QTOF) mass analyzer using electrospray ionization (ESI) measuring full scan and tandem mass spectra (MS/MS) in positive- and negative-ion modes with high mass accuracy. Our identification approach was based on m/z values measured with mass accuracy within 5 ppm tolerance in the full scan mode, characteristic fragment ions in MS/MS, and regularity in chromatographic retention dependences for individual lipid species, which provides the highest level of confidence for reported identifications of lipid species including regioisomeric and other isobaric forms. The graphs of dependences of retention times on the carbon number or on the number of double bond(s) in fatty acyl chains were constructed to support the identification of lipid species in homologous lipid series. Our list of identified lipid species is also compared with previous publications investigating human blood samples by various MS based approaches. In total, we have reported more than 500 lipid species representing 26 polar and nonpolar lipid classes detected in NIST Standard reference material 1950 human plasma.


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