WorldWideScience

Sample records for rapid mass learning

  1. Rapid generalization in phonotactic learning

    Directory of Open Access Journals (Sweden)

    Tal Linzen

    2017-10-01

    Full Text Available Speakers judge novel strings to be better potential words of their language if those strings consist of sound sequences that are attested in the language. These intuitions are often generalized to new sequences that share some properties with attested ones: Participants exposed to an artificial language where all words start with the voiced stops [b] and [d] will prefer words that start with other voiced stops (e.g., [g] to words that start with vowels or nasals. The current study tracks the evolution of generalization across sounds during the early stages of artificial language learning. In Experiments 1 and 2, participants received varying amounts of exposure to an artificial language. Learners rapidly generalized to new sounds: In fact, following short exposure to the language, attested patterns were not distinguished from unattested patterns that were similar in their phonological properties to the attested ones. Following additional exposure, participants showed an increasing preference for attested sounds, alongside sustained generalization to unattested ones. Finally, Experiment 3 tested whether participants can rapidly generalize to new sounds based on a single type of sound. We discuss the implications of our results for computational models of phonotactic learning.

  2. Rapid Prototyping of Mobile Learning Games

    Science.gov (United States)

    Federley, Maija; Sorsa, Timo; Paavilainen, Janne; Boissonnier, Kimo; Seisto, Anu

    2014-01-01

    This position paper presents the first results of an on-going project, in which we explore rapid prototyping method to efficiently produce digital learning solutions that are commercially viable. In this first phase, rapid game prototyping and an iterative approach was tested as a quick and efficient way to create learning games and to evaluate…

  3. Early gamma oscillations during rapid auditory processing in children with a language-learning impairment: changes in neural mass activity after training.

    Science.gov (United States)

    Heim, Sabine; Keil, Andreas; Choudhury, Naseem; Thomas Friedman, Jennifer; Benasich, April A

    2013-04-01

    Children with language-learning impairment (LLI) have consistently shown difficulty with tasks requiring precise, rapid auditory processing. Remediation based on neural plasticity assumes that the temporal precision of neural coding can be improved by intensive training protocols. Here, we examined the extent to which early oscillatory responses in auditory cortex change after audio-visual training, using combined source modeling and time-frequency analysis of the human electroencephalogram (EEG). Twenty-one elementary school students diagnosed with LLI underwent the intervention for an average of 32 days. Pre- and post-training assessments included standardized language/literacy tests and EEG recordings in response to fast-rate tone doublets. Twelve children with typical language development were also tested twice, with no intervention given. Behaviorally, improvements on measures of language were observed in the LLI group following completion of training. During the first EEG assessment, we found reduced amplitude and phase-locking of early (45-75 ms) oscillations in the gamma-band range (29-52 Hz), specifically in the LLI group, for the second stimulus of the tone doublet. Amplitude reduction for the second tone was no longer evident for the LLI children post-intervention, although these children still exhibited attenuated phase-locking. Our findings suggest that specific aspects of inefficient sensory cortical processing in LLI are ameliorated after training. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Rapid mass segregation in small stellar clusters

    Science.gov (United States)

    Spera, Mario; Capuzzo-Dolcetta, Roberto

    2017-12-01

    In this paper we focus our attention on small-to-intermediate N-body systems that are, initially, distributed uniformly in space and dynamically `cool' (virial ratios Q=2T/|Ω| below ˜0.3). In this work, we study the mass segregation that emerges after the initial violent dynamical evolution. At this scope, we ran a set of high precision N-body simulations of isolated clusters by means of HiGPUs, our direct summation N-body code. After the collapse, the system shows a clear mass segregation. This (quick) mass segregation occurs in two phases: the first shows up in clumps originated by sub-fragmentation before the deep overall collapse; this segregation is partly erased during the deep collapse to re-emerge, abruptly, during the second phase, that follows the first bounce of the system. In this second stage, the proper clock to measure the rate of segregation is the dynamical time after virialization, which (for cold and cool systems) may be significantly different from the crossing time evaluated from initial conditions. This result is obtained for isolated clusters composed of stars of two different masses (in the ratio mh/ml=2), at varying their number ratio, and is confirmed also in presence of a massive central object (simulating a black hole of stellar size). Actually, in stellar systems starting their dynamical evolution from cool conditions, the fast mass segregation adds to the following, slow, secular segregation which is collisionally induced. The violent mass segregation is an effect persistent over the whole range of N (128 ≤ N ≤1,024) investigated, and is an interesting feature on the astronomical-observational side, too. The semi-steady state reached after virialization corresponds to a mass segregated distribution function rather than that of equipartition of kinetic energy per unit mass as it should result from violent relaxation.

  5. In vitro rapid and mass multiplication of highly valuable medicinal ...

    African Journals Online (AJOL)

    In vitro rapid and mass multiplication of highly valuable medicinal plant Bacopa monnieri (L.) Wettst. Sudhir Sharma, Barkha Kamal, Neelima Rathi, Sudhir Chauhan, Vikas Jadon, Neha Vats, Ashok Gehlot, Sarita Arya ...

  6. Mass Casualties in Combat: Lessons Learned

    National Research Council Canada - National Science Library

    Beekley, Alex C

    2007-01-01

    .... Analysis of multiple and mass casualty events from current conflicts can provide critical lessons learned regarding triage and resource utilization that can potentially be applied to other conflicts...

  7. Integrated database for rapid mass movements in Norway

    Directory of Open Access Journals (Sweden)

    C. Jaedicke

    2009-03-01

    Full Text Available Rapid gravitational slope mass movements include all kinds of short term relocation of geological material, snow or ice. Traditionally, information about such events is collected separately in different databases covering selected geographical regions and types of movement. In Norway the terrain is susceptible to all types of rapid gravitational slope mass movements ranging from single rocks hitting roads and houses to large snow avalanches and rock slides where entire mountainsides collapse into fjords creating flood waves and endangering large areas. In addition, quick clay slides occur in desalinated marine sediments in South Eastern and Mid Norway. For the authorities and inhabitants of endangered areas, the type of threat is of minor importance and mitigation measures have to consider several types of rapid mass movements simultaneously.

    An integrated national database for all types of rapid mass movements built around individual events has been established. Only three data entries are mandatory: time, location and type of movement. The remaining optional parameters enable recording of detailed information about the terrain, materials involved and damages caused. Pictures, movies and other documentation can be uploaded into the database. A web-based graphical user interface has been developed allowing new events to be entered, as well as editing and querying for all events. An integration of the database into a GIS system is currently under development.

    Datasets from various national sources like the road authorities and the Geological Survey of Norway were imported into the database. Today, the database contains 33 000 rapid mass movement events from the last five hundred years covering the entire country. A first analysis of the data shows that the most frequent type of recorded rapid mass movement is rock slides and snow avalanches followed by debris slides in third place. Most events are recorded in the steep fjord

  8. Integrated database for rapid mass movements in Norway

    Science.gov (United States)

    Jaedicke, C.; Lied, K.; Kronholm, K.

    2009-03-01

    Rapid gravitational slope mass movements include all kinds of short term relocation of geological material, snow or ice. Traditionally, information about such events is collected separately in different databases covering selected geographical regions and types of movement. In Norway the terrain is susceptible to all types of rapid gravitational slope mass movements ranging from single rocks hitting roads and houses to large snow avalanches and rock slides where entire mountainsides collapse into fjords creating flood waves and endangering large areas. In addition, quick clay slides occur in desalinated marine sediments in South Eastern and Mid Norway. For the authorities and inhabitants of endangered areas, the type of threat is of minor importance and mitigation measures have to consider several types of rapid mass movements simultaneously. An integrated national database for all types of rapid mass movements built around individual events has been established. Only three data entries are mandatory: time, location and type of movement. The remaining optional parameters enable recording of detailed information about the terrain, materials involved and damages caused. Pictures, movies and other documentation can be uploaded into the database. A web-based graphical user interface has been developed allowing new events to be entered, as well as editing and querying for all events. An integration of the database into a GIS system is currently under development. Datasets from various national sources like the road authorities and the Geological Survey of Norway were imported into the database. Today, the database contains 33 000 rapid mass movement events from the last five hundred years covering the entire country. A first analysis of the data shows that the most frequent type of recorded rapid mass movement is rock slides and snow avalanches followed by debris slides in third place. Most events are recorded in the steep fjord terrain of the Norwegian west coast, but

  9. Rapid response learning of brand logo priming: Evidence that brand priming is not dominated by rapid response learning.

    Science.gov (United States)

    Boehm, Stephan G; Smith, Ciaran; Muench, Niklas; Noble, Kirsty; Atherton, Catherine

    2017-08-31

    Repetition priming increases the accuracy and speed of responses to repeatedly processed stimuli. Repetition priming can result from two complementary sources: rapid response learning and facilitation within perceptual and conceptual networks. In conceptual classification tasks, rapid response learning dominates priming of object recognition, but it does not dominate priming of person recognition. This suggests that the relative engagement of network facilitation and rapid response learning depends on the stimulus domain. Here, we addressed the importance of the stimulus domain for rapid response learning by investigating priming in another domain, brands. In three experiments, participants performed conceptual decisions for brand logos. Strong priming was present, but it was not dominated by rapid response learning. These findings add further support to the importance of the stimulus domain for the relative importance of network facilitation and rapid response learning, and they indicate that brand priming is more similar to person recognition priming than object recognition priming, perhaps because priming of both brands and persons requires individuation.

  10. Rapid identification of DNA-binding proteins by mass spectrometry

    DEFF Research Database (Denmark)

    Nordhoff, E; Krogsdam, A M; Jorgensen, H F

    1999-01-01

    We report a protocol for the rapid identification of DNA-binding proteins. Immobilized DNA probes harboring a specific sequence motif are incubated with cell or nuclear extract. Proteins are analyzed directly off the solid support by matrix-assisted laser desorption/ionization time-of-flight mass...... was validated by the identification of known prokaryotic and eukaryotic DNA-binding proteins, and its use provided evidence that poly(ADP-ribose) polymerase exhibits DNA sequence-specific binding to DNA....

  11. Differential Rapid Screening of Phytochemicals by Leaf Spray Mass Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Thomas; Graham Cooks, R. [Univ. of Innsbruck, Innsbruck (Austria)

    2014-03-15

    Ambient ionization can be achieved by generating an electrospray directly from plant tissue ('leaf spray'). The resulting mass spectra are characteristic of ionizable phytochemicals in the plant material. By subtracting the leaf spray spectra recorded from the petals of two hibiscus species H. moscheutos and H. syriacus one gains rapid access to the metabolites that differ most in the two petals. One such compound was identified as the sambubioside of quercitin (or delphinidin) while others are known flavones. Major interest centered on a C{sub 19}H{sub 29}NO{sub 5} compound that occurs only in the large H. moscheutos bloom. Attempts were made to characterize this compound by mass spectrometry alone as a test of such an approach. This showed that the compound is an alkaloid, assigned to the polyhydroxylated pyrrolidine class, and bound via a C{sub 3} hydrocarbon unit to a monoterpene.

  12. Detecting rapid mass movements using electrical self-potential measurements

    Science.gov (United States)

    Heinze, Thomas; Limbrock, Jonas; Pudasaini, Shiva P.; Kemna, Andreas

    2017-04-01

    Rapid mass movements are a latent danger for lives and infrastructure in almost any part of the world. Often such mass movements are caused by increasing pore pressure, for example, landslides after heavy rainfall or dam breaking after intrusion of water in the dam. Among several other geophysical methods used to observe water movement, the electrical self-potential method has been applied to a broad range of monitoring studies, especially focusing on volcanism and dam leakage but also during hydraulic fracturing and for earthquake prediction. Electrical self-potential signals may be caused by various mechanisms. Though, the most relevant source of the self-potential field in the given context is the streaming potential, caused by a flowing electrolyte through porous media with electrically charged internal surfaces. So far, existing models focus on monitoring water flow in non-deformable porous media. However, as the self-potential is sensitive to hydraulic parameters of the soil, any change in these parameters will cause an alteration of the electric signal. Mass movement will significantly influence the hydraulic parameters of the solid as well as the pressure field, assuming that fluid movement is faster than the pressure diffusion. We will present results of laboratory experiments under drained and undrained conditions with fluid triggered as well as manually triggered mass movements, monitored with self-potential measurements. For the undrained scenarios, we observe a clear correlation between the mass movements and signals in the electric potential, which clearly differ from the underlying potential variations due to increased saturation and fluid flow. In the drained experiments, we do not observe any measurable change in the electric potential. We therefore assume that change in fluid properties and release of the load causes disturbances in flow and streaming potential. We will discuss results of numerical simulations reproducing the observed effect. Our

  13. Modeling rapid mass movements using the shallow water equations

    Science.gov (United States)

    Hergarten, S.; Robl, J.

    2014-11-01

    We propose a new method to model rapid mass movements on complex topography using the shallow water equations in Cartesian coordinates. These equations are the widely used standard approximation for the flow of water in rivers and shallow lakes, but the main prerequisite for their application - an almost horizontal fluid table - is in general not satisfied for avalanches and debris flows in steep terrain. Therefore, we have developed appropriate correction terms for large topographic gradients. In this study we present the mathematical formulation of these correction terms and their implementation in the open source flow solver GERRIS. This novel approach is evaluated by simulating avalanches on synthetic and finally natural topographies and the widely used Voellmy flow resistance law. The results are tested against analytical solutions and the commercial avalanche model RAMMS. The overall results are in excellent agreement with the reference system RAMMS, and the deviations between the different models are far below the uncertainties in the determination of the relevant fluid parameters and involved avalanche volumes in reality. As this code is freely available and open source, it can be easily extended by additional fluid models or source areas, making this model suitable for simulating several types of rapid mass movements. It therefore provides a valuable tool assisting regional scale natural hazard studies.

  14. Rapid e-Learning Tools Selection Process for Cognitive and Psychomotor Learning Objectives

    Science.gov (United States)

    Ku, David Tawei; Huang, Yung-Hsin

    2012-01-01

    This study developed a decision making process for the selection of rapid e-learning tools that could match different learning domains. With the development of the Internet, the speed of information updates has become faster than ever. E-learning has rapidly become the mainstream for corporate training and academic instruction. In order to reduce…

  15. Rapidly progressive cryptogenic organising pneumonia presenting as a lung mass

    Science.gov (United States)

    Akram, Saeed; Irfan, Muhammad; Aftab, Kanwal

    2009-01-01

    A very rare case of a rapidly progressive variant of cryptogenic organising pneumonia (COP) presenting as a focal mass-like lesion with compression of the large airways leading to respiratory failure is described. A 60-year-old lady presented to the Aga Khan University Hospital Emergency Department in hypoxaemic respiratory failure with a 6-day history of dyspnoea, productive cough and fever. Chest x ray showed a right upper lobe mass-like lesion compressing the large airways and right pleural effusion. She deteriorated in the Emergency Department and was intubated due to worsening hypoxaemic respiratory failure. The pleural fluid and bronchoscopic specimens were negative on microbiological and cytological examination. CT-guided right lung biopsy revealed chronic non-specific inflammation without granuloma and malignancy. COP was diagnosed on video-assisted thoracoscopic (VATS) lung biopsy. She was successfully treated with high dose steroids and discharged in a stable condition; her 3-month follow-up chest x rays showed complete resolution of the lung lesion with some residual fibrosis. PMID:21686529

  16. The auditory brainstem is a barometer of rapid auditory learning.

    Science.gov (United States)

    Skoe, E; Krizman, J; Spitzer, E; Kraus, N

    2013-07-23

    To capture patterns in the environment, neurons in the auditory brainstem rapidly alter their firing based on the statistical properties of the soundscape. How this neural sensitivity relates to behavior is unclear. We tackled this question by combining neural and behavioral measures of statistical learning, a general-purpose learning mechanism governing many complex behaviors including language acquisition. We recorded complex auditory brainstem responses (cABRs) while human adults implicitly learned to segment patterns embedded in an uninterrupted sound sequence based on their statistical characteristics. The brainstem's sensitivity to statistical structure was measured as the change in the cABR between a patterned and a pseudo-randomized sequence composed from the same set of sounds but differing in their sound-to-sound probabilities. Using this methodology, we provide the first demonstration that behavioral-indices of rapid learning relate to individual differences in brainstem physiology. We found that neural sensitivity to statistical structure manifested along a continuum, from adaptation to enhancement, where cABR enhancement (patterned>pseudo-random) tracked with greater rapid statistical learning than adaptation. Short- and long-term auditory experiences (days to years) are known to promote brainstem plasticity and here we provide a conceptual advance by showing that the brainstem is also integral to rapid learning occurring over minutes. Copyright © 2013 IBRO. Published by Elsevier Ltd. All rights reserved.

  17. Rapid Statistical Learning Supporting Word Extraction From Continuous Speech.

    Science.gov (United States)

    Batterink, Laura J

    2017-07-01

    The identification of words in continuous speech, known as speech segmentation, is a critical early step in language acquisition. This process is partially supported by statistical learning, the ability to extract patterns from the environment. Given that speech segmentation represents a potential bottleneck for language acquisition, patterns in speech may be extracted very rapidly, without extensive exposure. This hypothesis was examined by exposing participants to continuous speech streams composed of novel repeating nonsense words. Learning was measured on-line using a reaction time task. After merely one exposure to an embedded novel word, learners demonstrated significant learning effects, as revealed by faster responses to predictable than to unpredictable syllables. These results demonstrate that learners gained sensitivity to the statistical structure of unfamiliar speech on a very rapid timescale. This ability may play an essential role in early stages of language acquisition, allowing learners to rapidly identify word candidates and "break in" to an unfamiliar language.

  18. [Rapid identification of microorganisms using MALDI-TOF mass spectrometry].

    Science.gov (United States)

    Sogawa, Kazuyuki; Watanabe, Masaharu; Nomura, Fumio

    2013-01-01

    In a clinical diagnostic microbiology laboratory, the current method of identifying bacterial isolates is based mainly on phenotypic characteristics, such as the growth pattern on different media, colony morphology, Gram stain, and various biochemical reactions. These techniques collectively allow high-level accuracy in identifying most bacterial isolates, but they are costly and time-consuming. In our clinical microbiology laboratory, we prospectively assessed the ability of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) to identify bacterial strains that were routinely isolated from clinical samples. Bacterial colonies obtained from a total of 468 strains of 92 bacterial species isolated at the Department of Clinical Laboratory at Chiba University were directly placed on target MALDI plates, followed by the addition of CHCA matrix solution. The plates were then subjected to MALDI-TOF MS measurement, and the microorganisms were identified by pattern matching by the libraries in the BioTyper 2.0 software. The identification rates at species and genus levels were 91.7% (429/468) and 97.0% (454/468), respectively. MALDI-TOF MS is a rapid, simple, and high-throughput proteomic technique for the identification of a variety of bacterial species. Since colony to colony differences and the effects of culture duration on the results are minimal, it can be implemented in a conventional laboratory setting. Although for some pathogens, the preanalytic processes should be refined and current database should be improved to obtain more accurate results, the MALDI-TOF MS-based method generally performs as well as the conventional methods and is a promising technology in clinical laboratories.

  19. Developing Collective Learning Extension for Rapidly Evolving Information System Courses

    Science.gov (United States)

    Agarwal, Nitin; Ahmed, Faysal

    2017-01-01

    Due to rapidly evolving Information System (IS) technologies, instructors find themselves stuck in the constant game of catching up. On the same hand students find their skills obsolete almost as soon as they graduate. As part of IS curriculum and education, we need to emphasize more on teaching the students "how to learn" while keeping…

  20. Holographic deep learning for rapid optical screening of anthrax spores.

    Science.gov (United States)

    Jo, YoungJu; Park, Sangjin; Jung, JaeHwang; Yoon, Jonghee; Joo, Hosung; Kim, Min-Hyeok; Kang, Suk-Jo; Choi, Myung Chul; Lee, Sang Yup; Park, YongKeun

    2017-08-01

    Establishing early warning systems for anthrax attacks is crucial in biodefense. Despite numerous studies for decades, the limited sensitivity of conventional biochemical methods essentially requires preprocessing steps and thus has limitations to be used in realistic settings of biological warfare. We present an optical method for rapid and label-free screening of Bacillus anthracis spores through the synergistic application of holographic microscopy and deep learning. A deep convolutional neural network is designed to classify holographic images of unlabeled living cells. After training, the network outperforms previous techniques in all accuracy measures, achieving single-spore sensitivity and subgenus specificity. The unique "representation learning" capability of deep learning enables direct training from raw images instead of manually extracted features. The method automatically recognizes key biological traits encoded in the images and exploits them as fingerprints. This remarkable learning ability makes the proposed method readily applicable to classifying various single cells in addition to B. anthracis, as demonstrated for the diagnosis of Listeria monocytogenes, without any modification. We believe that our strategy will make holographic microscopy more accessible to medical doctors and biomedical scientists for easy, rapid, and accurate point-of-care diagnosis of pathogens.

  1. Holographic deep learning for rapid optical screening of anthrax spores

    Science.gov (United States)

    Jo, YoungJu; Park, Sangjin; Jung, JaeHwang; Yoon, Jonghee; Joo, Hosung; Kim, Min-hyeok; Kang, Suk-Jo; Choi, Myung Chul; Lee, Sang Yup; Park, YongKeun

    2017-01-01

    Establishing early warning systems for anthrax attacks is crucial in biodefense. Despite numerous studies for decades, the limited sensitivity of conventional biochemical methods essentially requires preprocessing steps and thus has limitations to be used in realistic settings of biological warfare. We present an optical method for rapid and label-free screening of Bacillus anthracis spores through the synergistic application of holographic microscopy and deep learning. A deep convolutional neural network is designed to classify holographic images of unlabeled living cells. After training, the network outperforms previous techniques in all accuracy measures, achieving single-spore sensitivity and subgenus specificity. The unique “representation learning” capability of deep learning enables direct training from raw images instead of manually extracted features. The method automatically recognizes key biological traits encoded in the images and exploits them as fingerprints. This remarkable learning ability makes the proposed method readily applicable to classifying various single cells in addition to B. anthracis, as demonstrated for the diagnosis of Listeria monocytogenes, without any modification. We believe that our strategy will make holographic microscopy more accessible to medical doctors and biomedical scientists for easy, rapid, and accurate point-of-care diagnosis of pathogens. PMID:28798957

  2. Rapid maxillary anterior teeth retraction en masse by bone compression: a canine model

    National Research Council Canada - National Science Library

    Liu, Chufeng; Cao, Yang; Liu, Conghua; Zhang, Jincai; Xu, Pingping

    2011-01-01

    The present study sought to establish an animal model to study the feasibility and safety of rapid retraction of maxillary anterior teeth en masse aided by alveolar surgery in order to reduce orthodontic treatment time...

  3. Rapid and generic identification of influenza A and other respiratory viruses with mass spectrometry

    NARCIS (Netherlands)

    Majchrzykiewicz-Koehorst, J.A.; Heikens, E.; Trip, H.; Hulst, A.G.; Jong, A.L. de; Viveen, M.C.; Sedee, N.J.A.; van der Plas, J.; Coenjaerts, F.E.J.; Paauw, A.

    2015-01-01

    The rapid identification of existing and emerging respiratory viruses is crucial in combating outbreaks and epidemics. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a rapid and reliable identification method in bacterial diagnostics, but has not been

  4. Filopodia: A Rapid Structural Plasticity Substrate for Fast Learning

    Directory of Open Access Journals (Sweden)

    Ahmet S. Ozcan

    2017-06-01

    Full Text Available Formation of new synapses between neurons is an essential mechanism for learning and encoding memories. The vast majority of excitatory synapses occur on dendritic spines, therefore, the growth dynamics of spines is strongly related to the plasticity timescales. Especially in the early stages of the developing brain, there is an abundant number of long, thin and motile protrusions (i.e., filopodia, which develop in timescales of seconds and minutes. Because of their unique morphology and motility, it has been suggested that filopodia can have a dual role in both spinogenesis and environmental sampling of potential axonal partners. I propose that filopodia can lower the threshold and reduce the time to form new dendritic spines and synapses, providing a substrate for fast learning. Based on this proposition, the functional role of filopodia during brain development is discussed in relation to learning and memory. Specifically, it is hypothesized that the postnatal brain starts with a single-stage memory system with filopodia playing a significant role in rapid structural plasticity along with the stability provided by the mushroom-shaped spines. Following the maturation of the hippocampus, this highly-plastic unitary system transitions to a two-stage memory system, which consists of a plastic temporary store and a long-term stable store. In alignment with these architectural changes, it is posited that after brain maturation, filopodia-based structural plasticity will be preserved in specific areas, which are involved in fast learning (e.g., hippocampus in relation to episodic memory. These propositions aim to introduce a unifying framework for a diversity of phenomena in the brain such as synaptogenesis, pruning and memory consolidation.

  5. The Effects of Rapid Assessments and Adaptive Restudy Prompts in Multimedia Learning

    Science.gov (United States)

    Renkl, Alexander; Skuballa, Irene T.; Schwonke, Rolf; Harr, Nora; Leber, Jasmin

    2015-01-01

    We investigated the effects of rapid assessment tasks and different adaptive restudy prompts in multimedia learning. The adaptivity was based on rapid assessment tasks that were interspersed throughout a multimedia learning environment. In Experiment 1 (N = 52 university students), we analyzed to which extent rapid assessment tasks were reactive…

  6. The Role of Audiovisual Mass Media News in Language Learning

    Science.gov (United States)

    Bahrani, Taher; Sim, Tam Shu

    2011-01-01

    The present paper focuses on the role of audio/visual mass media news in language learning. In this regard, the two important issues regarding the selection and preparation of TV news for language learning are the content of the news and the linguistic difficulty. Content is described as whether the news is specialized or universal. Universal…

  7. MASS MEDIA AND ENGLISH LEARNING ACTIVITY IN BLITAR INDONESIA

    Directory of Open Access Journals (Sweden)

    Abdul Aziz

    2016-07-01

    Full Text Available This study is intended to know how English teachers in MTsN Selorejo, Blitar employ variety of English learning sources and implement English learning activity relevant to student’s learning preference in order to create joyful and conducive atmosphere of English learning activity to achieve the learning target better. The researcher uses qualitative method to conduct the study. The researcher analyzes the qualitative data from interview and observation in order to describe the phenomena. The findings show that the teachers use variety of English learning sources to enrich English learning materials that are easily to access and familiar to the students. The teachers use the materials from mass media like English corner and English program by radio, television, magazine, and newspaper to facilitate students to improve their English proficiency. The teachers design English learning activity relevant to student’s learning preference and talent based on materials from mass media. It makes students more motivated to learn English and easy to achieve the learning target.

  8. Effects of Spaced versus Massed Training in Function Learning

    Science.gov (United States)

    McDaniel, Mark A.; Fadler, Cynthia L.; Pashler, Harold

    2013-01-01

    A robust finding in the literature is that spacing material leads to better retention than massing; however, the benefit of spacing for concept learning is less clear. When items are massed, it may help the learner to discover the relationship between instances, leading to better abstraction of the underlying concept. Two experiments addressed…

  9. How we learn to make decisions: rapid propagation of reinforcement learning prediction errors in humans.

    Science.gov (United States)

    Krigolson, Olav E; Hassall, Cameron D; Handy, Todd C

    2014-03-01

    Our ability to make decisions is predicated upon our knowledge of the outcomes of the actions available to us. Reinforcement learning theory posits that actions followed by a reward or punishment acquire value through the computation of prediction errors-discrepancies between the predicted and the actual reward. A multitude of neuroimaging studies have demonstrated that rewards and punishments evoke neural responses that appear to reflect reinforcement learning prediction errors [e.g., Krigolson, O. E., Pierce, L. J., Holroyd, C. B., & Tanaka, J. W. Learning to become an expert: Reinforcement learning and the acquisition of perceptual expertise. Journal of Cognitive Neuroscience, 21, 1833-1840, 2009; Bayer, H. M., & Glimcher, P. W. Midbrain dopamine neurons encode a quantitative reward prediction error signal. Neuron, 47, 129-141, 2005; O'Doherty, J. P. Reward representations and reward-related learning in the human brain: Insights from neuroimaging. Current Opinion in Neurobiology, 14, 769-776, 2004; Holroyd, C. B., & Coles, M. G. H. The neural basis of human error processing: Reinforcement learning, dopamine, and the error-related negativity. Psychological Review, 109, 679-709, 2002]. Here, we used the brain ERP technique to demonstrate that not only do rewards elicit a neural response akin to a prediction error but also that this signal rapidly diminished and propagated to the time of choice presentation with learning. Specifically, in a simple, learnable gambling task, we show that novel rewards elicited a feedback error-related negativity that rapidly decreased in amplitude with learning. Furthermore, we demonstrate the existence of a reward positivity at choice presentation, a previously unreported ERP component that has a similar timing and topography as the feedback error-related negativity that increased in amplitude with learning. The pattern of results we observed mirrored the output of a computational model that we implemented to compute reward

  10. Rapid species specific identification and subtyping of Yersinia enterocolitica by MALDI-TOF mass spectrometry.

    Science.gov (United States)

    Stephan, Roger; Cernela, Nicole; Ziegler, Dominik; Pflüger, Valentin; Tonolla, Mauro; Ravasi, Damiana; Fredriksson-Ahomaa, Maria; Hächler, Herbert

    2011-11-01

    Yersinia enterocolitica are Gram-negative pathogens and known as important causes of foodborne infections. Rapid and reliable identification of strains of the species Y. enterocolitica within the genus Yersinia and the differentiation of the pathogenic from the non-pathogenic biotypes has become increasingly important. We evaluated here the application of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) for rapid species identification and subtyping of Y. enterocolitica. To this end, we developed a reference MS database library including 19 Y. enterocolitica (non-pathogenic biotype 1A and pathogenic biotypes 2 and 4) as well as 24 non-Y. enterocolitica strains, belonging to eleven different other Yersinia spp. The strains provided reproducible and unique mass spectra profiles covering a wide molecular mass range (2000 to 30,000 Da). Species-specific and biotype-specific biomarker protein mass patterns were determined for Y. enterocolitica. The defined biomarker mass patterns (SARAMIS SuperSpectrum™) were validated using 117 strains from various Y. enterocolitica bioserotypes in a blind-test. All strains were correctly identified and for all strains the mass spectrometry-based identification scheme yielded identical results compared to a characterization by a combination of biotyping and serotyping. Our study demonstrates that MALDI-TOF-MS is a reliable and powerful tool for the rapid identification of Y. enterocolitica strains to the species level and allows subtyping of strains to the biotype level. Copyright © 2011 Elsevier B.V. All rights reserved.

  11. Incorporating rapid neocortical learning of new schema-consistent information into complementary learning systems theory.

    Science.gov (United States)

    McClelland, James L

    2013-11-01

    The complementary learning systems theory of the roles of hippocampus and neocortex (McClelland, McNaughton, & O'Reilly, 1995) holds that the rapid integration of arbitrary new information into neocortical structures is avoided to prevent catastrophic interference with structured knowledge representations stored in synaptic connections among neocortical neurons. Recent studies (Tse et al., 2007, 2011) showed that neocortical circuits can rapidly acquire new associations that are consistent with prior knowledge. The findings challenge the complementary learning systems theory as previously presented. However, new simulations extending those reported in McClelland et al. (1995) show that new information that is consistent with knowledge previously acquired by a putatively cortexlike artificial neural network can be learned rapidly and without interfering with existing knowledge; it is when inconsistent new knowledge is acquired quickly that catastrophic interference ensues. Several important features of the findings of Tse et al. (2007, 2011) are captured in these simulations, indicating that the neural network model used in McClelland et al. has characteristics in common with neocortical learning mechanisms. An additional simulation generalizes beyond the network model previously used, showing how the rate of change of cortical connections can depend on prior knowledge in an arguably more biologically plausible network architecture. In sum, the findings of Tse et al. are fully consistent with the idea that hippocampus and neocortex are complementary learning systems. Taken together, these findings and the simulations reported here advance our knowledge by bringing out the role of consistency of new experience with existing knowledge and demonstrating that the rate of change of connections in real and artificial neural networks can be strongly prior-knowledge dependent. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  12. Colonisation and mass rearing: learning from others

    Directory of Open Access Journals (Sweden)

    Howell Paul I

    2009-11-01

    Full Text Available Abstract Mosquitoes, just as other insects produced for the sterile insect technique (SIT, are subjected to several unnatural processes including laboratory colonisation and large-scale factory production. After these processes, sterile male mosquitoes must perform the natural task of locating and mating with wild females. Therefore, the colonisation and production processes must preserve characters necessary for these functions. Fortunately, in contrast to natural selection which favours a suite of characteristics that improve overall fitness, colonisation and production practices for SIT strive to maximize only the few qualities that are necessary to effectively control populations. However, there is considerable uncertainty about some of the appropriate characteristics due to the lack of data. Development of biological products for other applications suggest that it is possible to identify and modify competitiveness characteristics in order to produce competitive mass produced sterile mosquitoes. This goal has been pursued - and sometimes achieved - by mosquito colonisation, production, and studies that have linked these characteristics to field performance. Parallels are drawn to studies in other insect SIT programmes and aquaculture which serve as vital technical reference points for mass-production of mosquitoes, most of whose development occurs - and characteristics of which are determined - in an aquatic environment. Poorly understood areas that require further study are numerous: diet, mass handling and genetic and physiological factors that influence mating competitiveness. Compromises in such traits due to demands to increase numbers or reduce costs, should be carefully considered in light of the desired field performance.

  13. measles immunisation growing peri-urban area of a mass a rapidly ...

    African Journals Online (AJOL)

    A mass measles immunisation campaign, with a target coverage rate of 85 - 90%, was launched in Khayelitsha, a rapidly growing urban township in the Cape Town area. Cross-sectional surveys of the measles immunisation status of resident 6 - 23-month-old infants were conducted immediately before, immediately after, ...

  14. Collision-induced fragmentation accurate mass spectrometric analysis methods to rapidly characterize plant extracts

    Science.gov (United States)

    The rapid advances in analytical chromatography equipment have made the reliable and reproducible measurement of a wide range of plant chemical components possible. Full chemical characterization of a given plant material is possible with the new mass spectrometers currently available. For phytochem...

  15. Collision-induced fragmentation accurate mass spectrometric analysis methods to rapidly characterize phytochemicals in plant extracts

    Science.gov (United States)

    The rapid advances in analytical chromatography equipment have made the reliable and reproducible measurement of a wide range of plant chemical components possible. Full chemical characterization of a given plant material is possible with the new mass spectrometers currently available. New methods a...

  16. Rapid learning dynamics in individual honeybees during classical conditioning

    OpenAIRE

    Pamir, Evren; Szyszka, Paul; Scheiner, Ricarda; Nawrot, Martin P

    2014-01-01

    Associative learning in insects has been studied extensively by a multitude of classical conditioning protocols. However, so far little emphasis has been put on the dynamics of learning in individuals. The honeybee is a well-established animal model for learning and memory. We here studied associative learning as expressed in individual behavior based on a large collection of data on olfactory classical conditioning (25 datasets, 3298 animals). We show that the group-averaged learning curve a...

  17. Rapid analysis of drug dissolution by paper spray ionization mass spectrometry.

    Science.gov (United States)

    Liu, Yang; Liu, Ning; Zhou, Ya-Nan; Lin, Lan; He, Lan

    2017-03-20

    With a great quantity of solid dosage tested by dissolution technology, developing a rapid and sensitive method to access the content of drug within dissolution media is highly desired by analysts and scientists. Traditionally, dissolution media is not compatible with mass spectrometry since the inorganic salts in the media might damage the mass spectrometer. Here, paper spray ionization mass spectrometry (PSI-MS), one of the ambient mass spectrometry technologies, is developed to characterize the content of drugs in dissolution media. The porous structure of paper can effectively retain salts from entering mass spectrometer. This makes the measurement of drug content within dissolution media by mass spectrometer possible. After the experimental parameters were optimized, calibration curves of model drugs - enalapril, quinapril and benazepril were established by using corresponding deuterated internal standards. PSI-MS was then deployed to characterize the content of enalapril from the dissolution testing of enalapril tablets. The results from PSI-MS are comparable to those from HPLC characterization. More importantly, the analysis time of 6 samples is shortened from 90min to 6min. Detection limit of enalapril maleate tablets by PSI-MS is 1/300 of LC. PSI-MS is rapid, sensitive and accurate in analyzing drug content from dissolution tests. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. People Mind Wander More during Massed than Spaced Inductive Learning

    Science.gov (United States)

    Metcalfe, Janet; Xu, Judy

    2016-01-01

    This article investigates the relation between mind wandering and the spacing effect in inductive learning. Participants studied works of art by different artists grouped in blocks, where works by a particular artist were either presented all together successively (the massed condition), or interleaved with the works of other artists (the spaced…

  19. Deep Learning for Tumor Classification in Imaging Mass Spectrometry.

    Science.gov (United States)

    Behrmann, Jens; Etmann, Christian; Boskamp, Tobias; Casadonte, Rita; Kriegsmann, Jörg; Maass, Peter

    2017-11-08

    Tumor classification using Imaging Mass Spectrometry (IMS) data has a high potential for future applications in pathology. Due to the complexity and size of the data, automated feature extraction and classification steps are required to fully process the data. Since mass spectra exhibit certain structural similarities to image data, deep learning may offer a promising strategy for classification of IMS data as it has been successfully applied to image classification. Methodologically, we propose an adapted architecture based on deep convolutional networks to handle the characteristics of mass spectrometry data, as well as a strategy to interpret the learned model in the spectral domain based on a sensitivity analysis. The proposed methods are evaluated on two algorithmically challenging tumor classification tasks and compared to a baseline approach. Competitiveness of the proposed methods are shown on both tasks by studying the performance via cross-validation. Moreover, the learned models are analyzed by the proposed sensitivity analysis revealing biologically plausible effects as well as confounding factors of the considered tasks. Thus, this study may serve as a starting point for further development of deep learning approaches in IMS classification tasks. https://gitlab.informatik.uni-bremen.de/digipath/Deep_Learning_for_Tumor_Classification_in_IMS. jbehrmann@uni-bremen.de, christianetmann@uni-bremen.de. Supplementary data are available at Bioinformatics online.

  20. Rapid learning dynamics in individual honeybees during classical conditioning

    Directory of Open Access Journals (Sweden)

    Evren ePamir

    2014-09-01

    Full Text Available Associative learning in insects has been studied extensively by a multitude of classical conditioning protocols. However, so far little emphasis has been put on the dynamics of learning in individuals. The honeybee is a well-established animal model for learning and memory. We here studied associative learning as expressed in individual behavior based on a large collection of data on olfactory classical conditioning (25 datasets, 3,298 animals. We show that the group-averaged learning curve and memory retention score confound three attributes of individual learning: the ability or inability to learn a given task, the generally fast acquisition of a conditioned response in learners, and the high stability of the conditioned response during consecutive training and memory retention trials. We reassessed the prevailing view that more training results in better memory performance and found that 24h memory retention can be indistinguishable after single-trial and multiple-trial conditioning in individuals. We explain how inter-individual differences in learning can be accommodated within the Rescorla-Wagner theory of associative learning. In both data-analysis and modeling we demonstrate how the conflict between population-level and single-animal perspectives on learning and memory can be disentangled.

  1. Identification of the Species of Origin for Meat Products by Rapid Evaporative Ionization Mass Spectrometry.

    Science.gov (United States)

    Balog, Julia; Perenyi, Dora; Guallar-Hoyas, Cristina; Egri, Attila; Pringle, Steven D; Stead, Sara; Chevallier, Olivier P; Elliott, Chris T; Takats, Zoltan

    2016-06-15

    Increasingly abundant food fraud cases have brought food authenticity and safety into major focus. This study presents a fast and effective way to identify meat products using rapid evaporative ionization mass spectrometry (REIMS). The experimental setup was demonstrated to be able to record a mass spectrometric profile of meat specimens in a time frame of <5 s. A multivariate statistical algorithm was developed and successfully tested for the identification of animal tissue with different anatomical origin, breed, and species with 100% accuracy at species and 97% accuracy at breed level. Detection of the presence of meat originating from a different species (horse, cattle, and venison) has also been demonstrated with high accuracy using mixed patties with a 5% detection limit. REIMS technology was found to be a promising tool in food safety applications providing a reliable and simple method for the rapid characterization of food products.

  2. [A young man with rapidly progressing dyspnoea and a mediastinal mass].

    Science.gov (United States)

    van Spronsen, D J; van den Berkmortel, F W P J; Bootsma, G P; de Mulder, P H M

    2004-11-13

    An 18-year-old male presented with a 2-week history of rapid progressive dyspnoea and dry cough due to a large mediastinal mass with compression of the trachea. Based on the raised serum values of the tumour markers chorionogonadotrophin and alphafoetoprotein the diagnosis of germ-cell tumour was made. Because of the severity of his symptoms chemotherapy with bleomycin, etoposide and cisplatin was begun on the same day and before the results of the histology investigations were known. The next day the symptoms were diminished and after completing four courses of chemotherapy there was complete remission. The differential diagnosis of a rapid progressive mediastinal mass is limited and mainly relates to malignant lymphoma and germ-cell tumours. In emergency situations if tumour markers are raised then anti-tumour therapy may be begun before any histological confirmation is available.

  3. CONSTRAINTS ON THE MASS AND RADIUS OF THE ACCRETING NEUTRON STAR IN THE RAPID BURSTER

    Energy Technology Data Exchange (ETDEWEB)

    Sala, G.; Jose, J.; Parikh, A.; Longland, R. [Departament de Fisica i Enginyeria Nuclear, EUETIB, Universitat Politecnica de Catalunya, c/ Comte d' Urgell 187, E-08036 Barcelona (Spain); Haberl, F. [Max-Planck-Institut fuer extraterrestrische Physik, Giessenbachstrasse, D-85748 Garching (Germany); Pardo, L. C. [Grup de Caracteritzacio de Materials, Departament de Fisica i Enginyeria Nuclear, ETSEIB, Universitat Politecnica de Catalunya, Diagonal 647, E-08028 Barcelona, Catalonia (Spain); Andersen, M. [Research and Scientific Support Department, European Space Agency, ESTEC, Keplerlaan 1, NL-2200 AG Noordwijk (Netherlands)

    2012-06-20

    The Rapid Burster (MXB 1730-335) is a unique object, showing both type I and type II X-ray bursts. A type I burst of the Rapid Burster was observed with Swift/X-Ray Telescope on 2009 March 5, showing photospheric radius expansion (PRE) for the first time in this source. We report here on the mass and radius determination from this PRE burst using a Bayesian approach. After marginalization over the likely distance of the system (5.8-10 kpc), we obtain M = 1.1 {+-} 0.3 M{sub Sun} and R = 9.6 {+-} 1.5 km (1{sigma} uncertainties) for the compact object, ruling out the stiffest equations of state for the neutron star. We study the sensitivity of the results to the distance, the color correction factor, and the hydrogen mass fraction in the envelope. We find that only the distance plays a crucial role.

  4. Considerations for Task Analysis Methods and Rapid E-Learning Development Techniques

    Directory of Open Access Journals (Sweden)

    Dr. Ismail Ipek

    2014-02-01

    Full Text Available The purpose of this paper is to provide basic dimensions for rapid training development in e-learning courses in education and business. Principally, it starts with defining task analysis and how to select tasks for analysis and task analysis methods for instructional design. To do this, first, learning and instructional technologies as visions of the future were discussed. Second, the importance of task analysis methods in rapid e-learning was considered, with learning technologies as asynchronous and synchronous e-learning development. Finally, rapid instructional design concepts and e-learning design strategies were defined and clarified with examples, that is, all steps for effective task analysis and rapid training development techniques based on learning and instructional design approaches were discussed, such as m-learning and other delivery systems. As a result, the concept of task analysis, rapid e-learning development strategies and the essentials of online course design were discussed, alongside learner interface design features for learners and designers.

  5. Dynamical Mass Measurements of Contaminated Galaxy Clusters Using Machine Learning

    Science.gov (United States)

    Ntampaka, M.; Trac, H.; Sutherland, D. J.; Fromenteau, S.; Póczos, B.; Schneider, J.

    2016-11-01

    We study dynamical mass measurements of galaxy clusters contaminated by interlopers and show that a modern machine learning algorithm can predict masses by better than a factor of two compared to a standard scaling relation approach. We create two mock catalogs from Multidark’s publicly available N-body MDPL1 simulation, one with perfect galaxy cluster membership information and the other where a simple cylindrical cut around the cluster center allows interlopers to contaminate the clusters. In the standard approach, we use a power-law scaling relation to infer cluster mass from galaxy line-of-sight (LOS) velocity dispersion. Assuming perfect membership knowledge, this unrealistic case produces a wide fractional mass error distribution, with a width of {{Δ }}ε ≈ 0.87. Interlopers introduce additional scatter, significantly widening the error distribution further ({{Δ }}ε ≈ 2.13). We employ the support distribution machine (SDM) class of algorithms to learn from distributions of data to predict single values. Applied to distributions of galaxy observables such as LOS velocity and projected distance from the cluster center, SDM yields better than a factor-of-two improvement ({{Δ }}ε ≈ 0.67) for the contaminated case. Remarkably, SDM applied to contaminated clusters is better able to recover masses than even the scaling relation approach applied to uncontaminated clusters. We show that the SDM method more accurately reproduces the cluster mass function, making it a valuable tool for employing cluster observations to evaluate cosmological models.

  6. The rapid emergence of stimulus specific perceptual learning

    Directory of Open Access Journals (Sweden)

    Zahra eHussain

    2012-07-01

    Full Text Available Is stimulus specific perceptual learning the result of extended practice or does it emerge early in the time course of learning? We examined this issue by manipulating the amount of practice given on a face identification task on Day 1, and altering the familiarity of stimuli on Day 2. We found that a small number of trials was sufficient to produce stimulus specific perceptual learning of faces: on Day 2, response accuracy decreased by the same amount for novel stimuli regardless of whether observers practiced 105 or 840 trials on Day 1. Current models of learning assume early procedural improvements followed by late stimulus specific gains. Our results show that stimulus specific and procedural improvements are distributed throughout the time course of learning

  7. Lessons learned from Rapid Response Research on wildland fires

    Science.gov (United States)

    Leigh Lentile; Penny Morgan; Colin Hardy; Andrew Hudak; Robert Means; Roger Ottmar; Peter Robichaud; Elaine Sutherland; Frederick Way; Sarah Lewis

    2007-01-01

    In recent years, more researchers are collecting data either on active wildfires or immediately after wildfire occurrence. Known as Rapid Response Research, this important undertaking provides real-time information, useful data, and improved tools for managers.

  8. Dissociation of rapid response learning and facilitation in perceptual and conceptual networks of person recognition.

    Science.gov (United States)

    Valt, Christian; Klein, Christoph; Boehm, Stephan G

    2015-08-01

    Repetition priming is a prominent example of non-declarative memory, and it increases the accuracy and speed of responses to repeatedly processed stimuli. Major long-hold memory theories posit that repetition priming results from facilitation within perceptual and conceptual networks for stimulus recognition and categorization. Stimuli can also be bound to particular responses, and it has recently been suggested that this rapid response learning, not network facilitation, provides a sound theory of priming of object recognition. Here, we addressed the relevance of network facilitation and rapid response learning for priming of person recognition with a view to advance general theories of priming. In four experiments, participants performed conceptual decisions like occupation or nationality judgments for famous faces. The magnitude of rapid response learning varied across experiments, and rapid response learning co-occurred and interacted with facilitation in perceptual and conceptual networks. These findings indicate that rapid response learning and facilitation in perceptual and conceptual networks are complementary rather than competing theories of priming. Thus, future memory theories need to incorporate both rapid response learning and network facilitation as individual facets of priming. © 2014 The British Psychological Society.

  9. The effects in humans of rapid loss of body mass on a boxing-related task.

    Science.gov (United States)

    Smith, M S; Dyson, R; Hale, T; Harrison, J H; McManus, P

    2000-09-01

    The physiological effects of strategies for a rapid loss of body mass immediately before weighing-in for competition in weight-governed sports are unclear. This study examined the effects of a 3%-4% loss in body mass on a boxing-related task. Seven novice amateur boxers completed three 3 min rounds of simulated boxing on a prototype boxing ergometer in an euhydrated state (E-trial) and after exercise-induced thermal dehydration (D-trial). All subjects lost body mass following dehydration-mean body mass fell 3.8 (SD +/- 0.3)% [77.3 (SD +/- 11.3) to 74.4 (SD +/- 10.7) kg, PPV) were inconsistent. Four subjects suffered reductions in PV between 15% and 30%, one subject maintained his E-trial value and two recorded an increase. The D-trial mean PV value was 8.0 (SD +/- 17.2)% lower but this fall was not statistically significant (P>0.05). Analysis of D-trial boxing performance showed one subject maintained his performance over the two trials and a second improved 17.8%. A two-way ANOVA (condition x time) with repeated measures on both factors showed no significant main effect differences for condition (F1,6 = 3.93 P>0.05), time (F1.83,48 = 1.12, P>0.05) or interaction between them (F1.93,48, P>0.05). Furthermore, neither heart rate nor blood lactate responses in the boxing task differed between trials. These data were affected by the small sample. Power and effect size analysis using eta(2) procedure and removing the outlier data produced a mean fall in boxing performance of 26.8%. However, some subjects appeared able to resist the deleterious effects of a rapid loss of body mass prior to competition and further research is needed to explain the mechanisms under-pinning this ability.

  10. Rapid Analysis of Corni fructus Using Paper Spray-Mass Spectrometry.

    Science.gov (United States)

    Guo, Yuan; Gu, Zhixin; Liu, Xuemei; Liu, Jingjing; Ma, Ming; Chen, Bo; Wang, Liping

    2017-07-01

    Paper spray-mass spectrometry (PS-MS) is a kind of ambient MS technique for the rapid analysis of samples. Corni fructus has been widely used in traditional Chinese compound preparations and healthy food. However, a number of counterfeits of Corni fructus, such as Crataegi fructus, Lycii fructus, and grape skin are illegally sold in crude herb markets. Therefore, the development of a rapid and high-throughput quality evaluation method is important for ensuring the effectiveness and safety of the crude materials of Corni fructus. To develop PS-MS chemical profiles and a semi-quantitative method of Corni fructus for quality assessment and control, and species distinction of Corni fructus. Both positive and negative ion PS-MS chemical profiles were constructed for species distinction. The statistical analysis of the chemical profiles was accomplished by principal component analysis (PCA). Rapid semi-quantitative analysis of loganin and morroniside in the extracts of Corni fructus were accomplished by PS-MS. The profiles of the Corni fructus and Crataegi fructus samples were clearly clustered into two categories. The limit of quantification (LOQ) in the semi-quantitative analysis was 6 μg/mL and 5.6 μg/mL for loganin and morroniside, respectively. PS-MS is a simple, rapid, and high-throughput method for the quality control and species distinction of Corni fructus. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  11. Elastic uplift in southeast Greenland due to rapid ice mass loss

    DEFF Research Database (Denmark)

    Khan, Shfaqat Abbas; Van dam, Tonie; Hamilton, Gordon S.

    2007-01-01

    , calculated from sequential digital elevation models, contributes about 16 mm of the observed uplift, with an additional 5 mm from volume loss of Kangerdlugssuaq Glacier. The remaining uplift signal is attributed to significant melt-induced ice volume loss from the ice sheet margin along the southeast coast......The rapid unloading of ice from the southeastern sector of the Greenland ice sheet between 2001 and 2006 caused an elastic uplift of 35 mm at a GPS site in Kulusuk. Most of the uplift results from ice dynamic-induced volume losses on two nearby outlet glaciers. Volume loss from Helheim Glacier...... between 62N and 66N. Citation: Khan, S. A., J. Wahr, L. A. Stearns, G. S. Hamilton, T. van Dam, K. M. Larson, and O. Francis (2007), Elastic uplift in southeast Greenland due to rapid ice mass loss....

  12. Coral mass spawning predicted by rapid seasonal rise in ocean temperature

    KAUST Repository

    Keith, Sally A.

    2016-05-11

    Coral spawning times have been linked to multiple environmental factors; however, to what extent these factors act as generalized cues across multiple species and large spatial scales is unknown. We used a unique dataset of coral spawning from 34 reefs in the Indian and Pacific Oceans to test if month of spawning and peak spawning month in assemblages of Acropora spp. can be predicted by sea surface temperature (SST), photosynthetically available radiation, wind speed, current speed, rainfall or sunset time. Contrary to the classic view that high mean SST initiates coral spawning, we found rapid increases in SST to be the best predictor in both cases (month of spawning: R2 = 0.73, peak: R2 = 0.62). Our findings suggest that a rapid increase in SST provides the dominant proximate cue for coral mass spawning over large geographical scales. We hypothesize that coral spawning is ultimately timed to ensure optimal fertilization success.

  13. Promoting Rapid Learning in the Histology Laboratory by Integrating Technology

    Science.gov (United States)

    Shields, Vonnie

    2008-01-01

    This paper describes the results of incorporating technology in the histology laboratory by using high-resolution video-imaging equipment (VIE). The study sought to determine if (1) the VIE would allow students to more easily and rapidly find histological structures over more conventional methods, and (2) if they could find the structures with the…

  14. Seed oil polyphenols: rapid and sensitive extraction method and high resolution-mass spectrometry identification.

    Science.gov (United States)

    Koubaa, Mohamed; Mhemdi, Houcine; Vorobiev, Eugène

    2015-05-01

    Phenolic content is a primary parameter for vegetables oil quality evaluation, and directly involved in the prevention of oxidation and oil preservation. Several methods have been reported in the literature for polyphenols extraction from seed oil but the approaches commonly used remain manually handled. In this work, we propose a rapid and sensitive method for seed oil polyphenols extraction and identification. For this purpose, polyphenols were extracted from Opuntia stricta Haw seed oil, using high frequency agitation, separated, and then identified using a liquid chromatography-high resolution mass spectrometry method. Our results showed good sensitivity and reproducibility of the developed methods. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. [Rapid detection of antimicrobial resistance by MALDI-TOF mass spectrometry].

    Science.gov (United States)

    Oviaño, Marina; Dolores Rojo, María; Navarro Marí, José María; Bou, Germán

    2016-06-01

    In recent years, MALDI-TOF (matrix-assisted laser desorption ionization time-of-flight) mass spectrometry has become established as a first-line diagnostic tool in the identification of microorganisms, including those producing human infections. Rapid detection of antimicrobial resistance is one of the future applications of this technique with the greatest likelihood of success. This review describes the most important studies published in this field and discusses potential future challenges and the clinical application of this technique in the next few years. Copyright © 2016 Elsevier España, S.L.U. All rights reserved.

  16. Rapid detection of milk adulteration using intact protein flow injection mass spectrometric fingerprints combined with chemometrics.

    Science.gov (United States)

    Du, Lijuan; Lu, Weiying; Cai, Zhenzhen Julia; Bao, Lei; Hartmann, Christoph; Gao, Boyan; Yu, Liangli Lucy

    2018-02-01

    Flow injection mass spectrometry (FIMS) combined with chemometrics was evaluated for rapidly detecting economically motivated adulteration (EMA) of milk. Twenty-two pure milk and thirty-five counterparts adulterated with soybean, pea, and whey protein isolates at 0.5, 1, 3, 5, and 10% (w/w) levels were analyzed. The principal component analysis (PCA), partial least-squares-discriminant analysis (PLS-DA), and support vector machine (SVM) classification models indicated that the adulterated milks could successfully be classified from the pure milks. FIMS combined with chemometrics might be an effective method to detect possible EMA in milk. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Rapid E-learning Development Strategies and a Multimedia Project Design Model

    OpenAIRE

    Ömer Faruk Sözcü; İsmail İpek

    2014-01-01

    The purpose of the study is to discuss e-learning design strategies which can be used for multimedia projects as a design model. Recent advances in instructional technologies have been found to be very important in the design of training courses by using rapid instructional design (ID) approaches. The approaches were developed to use in training and developing e-learning projects as well as multimedia design tools. For this reason, this paper will clarify the basic e-learning development tech...

  18. Rapid and sensitive liquid chromatography-mass spectrometry method for determination of ropinirole in human plasma.

    Science.gov (United States)

    Bhatt, Jignesh; Jangid, Arvind; Shetty, Raghavendra; Shah, Bhavin; Kambli, Sandeep; Subbaiah, Gunta; Singh, Sadhana

    2006-03-18

    A rapid and robust liquid chromatography-mass spectrometry (LC-MS/MS) method was developed for non-ergoline dopamine D(2)-receptor agonist, ropinirole in human plasma using Es-citalopram oxalate as an internal standard. The method involves solid phase extraction from plasma, reversed-phase simple isocratic chromatographic conditions and mass spectrometric detection that enables a detection limit at picogram levels. The proposed method was validated with linear range of 20-1,200 pg/ml. The extraction recoveries for ropinirole and internal standard were 90.45 and 65.42%, respectively. The R.S.D.% of intra-day and inter-day assay was lower than 15%. For its sensitivity and reliability, the proposed method is particularly suitable for pharmacokinetic studies.

  19. Accessible surfaces of beta proteins increase with increasing protein molecular mass more rapidly than those of other proteins.

    Directory of Open Access Journals (Sweden)

    Anna V Glyakina

    Full Text Available Here we present a systematic analysis of accessible surface areas and hydrogen bonds of 2554 globular proteins from four structural classes (all-α, all-β, α/β and α+β proteins that is aimed to learn in which structural class the accessible surface area increases with increasing protein molecular mass more rapidly than in other classes, and what structural peculiarities are responsible for this effect. The beta structural class of proteins was found to be the leader, with the following possible explanations of this fact. First, in beta structural proteins, the fraction of residues not included in the regular secondary structure is the largest, and second, the accessible surface area of packaged elements of the beta-structure increases more rapidly with increasing molecular mass in comparison with the alpha-structure. Moreover, in the beta structure, the probability of formation of backbone hydrogen bonds is higher than that in the alpha helix for all residues of α+β proteins (the average probability is 0.73±0.01 for the beta-structure and 0.60±0.01 for the alpha-structure without proline and α/β proteins, except for asparagine, aspartic acid, glycine, threonine, and serine (0.70±0.01 for the beta-structure and 0.60±0.01 for the alpha-structure without the proline residue. There is a linear relationship between the number of hydrogen bonds and the number of amino acid residues in the protein (Number of hydrogen bonds=0.678·number of residues-3.350.

  20. Rapid discrimination of fatty acid composition in fats and oils by electrospray ionization mass spectrometry.

    Science.gov (United States)

    Kurata, Shoji; Yamaguchi, Kazutaka; Nagai, Masatoshi

    2005-12-01

    Fatty acids in 42 types of saponified vegetable and animal oils were analyzed by electrospray ionization mass spectrometry (ESI-MS) for the development of their rapid discrimination. The compositions were compared with those analyzed by gas chromatography-mass spectrometry (GC-MS), a more conventional method used in the discrimination of fats and oils. Fatty acids extracted with 2-propanol were-detected as deprotonated molecular ions ([M-H]-) in the ESI-MS spectra of the negative-ion mode. The composition obtained by ESI-MS corresponded to the data of the total ion chromatograms by GC-MS. The ESI-MS analysis discriminated the fats and oils within only one minute after starting the measurement. The detection limit for the analysis was approximately 10(-10) g as a sample amount analyzed for one minute. This result showed that the ESI-MS analysis discriminated the fats and oils much more rapidly and sensitively than the GC-MS analysis, which requires several tens of minutes and approximately 10(-9) g. Accordingly, the ESI-MS analysis was found to be suitable for a screening procedure for the discrimination of fats and oils.

  1. Modelling rapid mass movements using the shallow water equations in Cartesian coordinates

    Science.gov (United States)

    Hergarten, S.; Robl, J.

    2015-03-01

    We propose a new method to model rapid mass movements on complex topography using the shallow water equations in Cartesian coordinates. These equations are the widely used standard approximation for the flow of water in rivers and shallow lakes, but the main prerequisite for their application - an almost horizontal fluid table - is in general not satisfied for avalanches and debris flows in steep terrain. Therefore, we have developed appropriate correction terms for large topographic gradients. In this study we present the mathematical formulation of these correction terms and their implementation in the open-source flow solver GERRIS. This novel approach is evaluated by simulating avalanches on synthetic and finally natural topographies and the widely used Voellmy flow resistance law. Testing the results against analytical solutions and the proprietary avalanche model RAMMS, we found a very good agreement. As the GERRIS flow solver is freely available and open source, it can be easily extended by additional fluid models or source areas, making this model suitable for simulating several types of rapid mass movements. It therefore provides a valuable tool for assisting regional-scale natural hazard studies.

  2. Rapid and Concomitant Analysis of Pharmaceuticals in Treated Wastewater by Coated Blade Spray Mass Spectrometry.

    Science.gov (United States)

    Poole, Justen J; Gómez-Ríos, German A; Boyaci, Ezel; Reyes-Garcés, Nathaly; Pawliszyn, Janusz

    2017-11-07

    The widespread use of pharmaceuticals in both human and animal populations, and the resultant contamination of surface waters from the outflow of water treatment facilities is an issue of growing concern. This has raised the need for analytical methods that can both perform rapid sample analysis and overcome the limitations of conventional analysis procedures, such as multistep workflows and tedious procedures. Coated blade spray (CBS) is a solid-phase microextraction based technique that enables the direct-to-mass-spectrometry analysis of extracted compounds via the use of limited organic solvent to desorb analytes and perform electrospray ionization. This paper documents how CBS can be applied for the concomitant tandem mass spectrometric (MS/MS) analysis of nine pharmaceuticals in treated wastewater. The total analysis times of less than 11 min provided limits of detection lower than 50 ng L-1 for all target compounds in river water. The CBS methodology was then compared to a conventional solid-phase extraction technique for the analysis of the final effluent of six wastewater treatment facilities. The experimental results strongly suggest that CBS offers scientists a viable alternative method for analyzing water samples that is both rapid and relatively solvent-free.

  3. Rapid fingerprinting of lignin by ambient ionization high resolution mass spectrometry and simplified data mining.

    Science.gov (United States)

    Crawford, Elizabeth A; Gerbig, Stefanie; Spengler, Bernhard; Volmer, Dietrich A

    2017-11-22

    Ambient ionization techniques are typically used to analyze samples in their native states with minimal or no sample pretreatment prior to mass spectrometric (MS) analysis. Desorption electrospray ionization (DESI) and direct analysis in real time (DART) were systematically investigated in this work for direct solid analysis of depolymerized lignin samples, with the goal of rapidly fingerprinting these samples, to efficiently characterize the subunits of this renewable energy source. High resolution MS was required for enhanced selectivity in this study due to the inherent structural complexity of lignin. DESI provided results across a broader mass range (up to m/z 700) than DART and also ionized saturated compounds of low oxygen-to-carbon (O/C) ratios and low double bond equivalents (DBE). While DART detected the same core lignin monomeric and dimeric compounds as seen with DESI and electrospray ionization (ESI), results were restricted to a narrower mass range to m/z 500, due to thermal degradation and losses of methoxy groups. In contrast to DESI and ESI, the DART spectra were nearly void of saturated components. On a structural level, the core lignin compounds were visually fingerprinted and ionization method performances critically assessed by employing simplified Kendrick-based data mining approaches. A novel simplified data visualization approach was developed in this work based on modified Kendrick mass defect (KMD) filtering for lignin subunits and plotting the mass defect values against the degree of unsaturation. Direct visualization of monomeric, dimeric and trimeric lignin species was simplified by the KMD separation plots, easily allowing the core lignin compounds to be visually identified and compared. Modified KMD bases, namely methoxy and phenol bases, which represent monomer-specific lignin constituents, were successfully used to classify and group the complex mixture of lignin species. Further separation of methoxy-related lignin species was

  4. 'Rapid Learning health care in oncology' - an approach towards decision support systems enabling customised radiotherapy'.

    Science.gov (United States)

    Lambin, Philippe; Roelofs, Erik; Reymen, Bart; Velazquez, Emmanuel Rios; Buijsen, Jeroen; Zegers, Catharina M L; Carvalho, Sara; Leijenaar, Ralph T H; Nalbantov, Georgi; Oberije, Cary; Scott Marshall, M; Hoebers, Frank; Troost, Esther G C; van Stiphout, Ruud G P M; van Elmpt, Wouter; van der Weijden, Trudy; Boersma, Liesbeth; Valentini, Vincenzo; Dekker, Andre

    2013-10-01

    An overview of the Rapid Learning methodology, its results, and the potential impact on radiotherapy. Rapid Learning methodology is divided into four phases. In the data phase, diverse data are collected about past patients, treatments used, and outcomes. Innovative information technologies that support semantic interoperability enable distributed learning and data sharing without additional burden on health care professionals and without the need for data to leave the hospital. In the knowledge phase, prediction models are developed for new data and treatment outcomes by applying machine learning methods to data. In the application phase, this knowledge is applied in clinical practice via novel decision support systems or via extensions of existing models such as Tumour Control Probability models. In the evaluation phase, the predictability of treatment outcomes allows the new knowledge to be evaluated by comparing predicted and actual outcomes. Personalised or tailored cancer therapy ensures not only that patients receive an optimal treatment, but also that the right resources are being used for the right patients. Rapid Learning approaches combined with evidence based medicine are expected to improve the predictability of outcome and radiotherapy is the ideal field to study the value of Rapid Learning. The next step will be to include patient preferences in the decision making. Copyright © 2013 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

  5. Rapid weight loss and the body fluid balance and hemoglobin mass of elite amateur boxers.

    Science.gov (United States)

    Reljic, Dejan; Hässler, Eike; Jost, Joachim; Friedmann-Bette, Birgit

    2013-01-01

    Dehydration is assumed to be a major adverse effect associated with rapid loss of body mass for competing in a lower weight class in combat sports. However, the effects of such weight cutting on body fluid balance in a real-life setting are unknown. To examine the effects of 5% or greater loss of body mass within a few days before competition on body water, blood volume, and plasma volume in elite amateur boxers. Case-control study. Sports medicine laboratory. Seventeen male boxers (age = 19.2 ± 2.9 years, height = 175.1 ± 7.0 cm, mass = 65.6 ± 9.2 kg) were assigned to the weight-loss group (WLG; n = 10) or the control group (CON; n = 7). The WLG reduced body mass by restricting fluid and food and inducing excessive sweat loss by adhering to individual methods. The CON participated in their usual precompetition training. During an ordinary training period (t-1), 2 days before competition (t-2), and 1 week after competition (t-3), we performed bioelectrical impedance measurements; calculated total body water, intracellular water, and extracellular water; and estimated total hemoglobin mass (tHbmass), blood volume, and plasma volume by the CO-rebreathing method. In the WLG, the loss of body mass (5.6% ± 1.7%) led to decreases in total body water (6.0% ± 0.9%), extracellular water (12.4% ± 7.6%), tHbmass (5.3% ± 3.8%), blood volume (7.6% ± 2.1%; P .05). At t-3, total body water, extracellular water, and plasma volume had returned to near baseline values, but tHbmass and blood volume still were less than baseline values (P .05). In a real-life setting, the loss of approximately 6% body mass within 5 days induced hypohydration, which became evident by the decreases in body water and plasma volume. The reduction in tHbmass was a surprising observation that needs further investigation.

  6. Rapid confirmatory analysis of avermectin residues in milk by liquid chromatography tandem mass spectrometry

    Directory of Open Access Journals (Sweden)

    Nurullah Ozdemir

    2016-01-01

    Full Text Available Our study developed a quick method for confirmatory analysis of avermectins (abamectin B1a, doramectin, ivermectin B1a, eprinomectin B1a, and moxidectin in bovine milk according to the European Commission Decision 2002/657/EC requirements. Avermectins were liquid–liquid extracted with acetonitrile, followed by an evaporation step, and then analyzed by liquid chromatography/electrospray ionization tandem mass spectrometry in the negative ion mode. An in-house method validation was performed and the data reported on specificity, linearity, recovery, limit of detection, limit of quantitation, decision limit, and detection capability. The advantage of this method is that low levels of avermectins are detectable and quantitatively confirmed at a rapid rate in milk.

  7. The Impacts of the Mass Rapid Transit System on Household Car Ownership in Taipei

    Directory of Open Access Journals (Sweden)

    Wen-Hsiu Huang

    2014-06-01

    Full Text Available This paper investigates the impacts of Taipei Mass Rapid Transit (MRT system on household car ownership and analyses how socioeconomic characteristics affect household car ownership. We employ a difference-in-difference (DID strategy integrated with generalized Poisson regression models to examine the effects of MRT. The results are as follows: first, the establishment of Taipei MRT significantly reduced the level of household car ownership. Expanding the network of MRT system can be a feasible policy to control car ownership. Second, the levels of household car ownership are related to household’s socioeconomic characteristics. Third, households with high dependence on public transport own fewer cars after Taipei MRT began operation. Hence, the traffic authority should adopt more effective methods to encourage public transit use in order to decrease household car ownership.

  8. Qualitative CFD for Rapid Learning in Industrial and Academic Applications

    Science.gov (United States)

    Variano, Evan

    2010-11-01

    We present a set of tools that allow CFD to be used at an early stage in the design process. Users can rapidly explore the qualitative aspects of fluid flow using real-time simulations that react immediately to design changes. This can guide the design process by fostering an intuitive understanding of fluid dynamics at the prototyping stage. We use an extremely stable Navier-Stokes solver that is available commercially (and free to academic users) plus a custom user interface. The code is designed for the animation and gaming industry, and we exploit the powerful graphical display capabilities to develop a unique human-machine interface. This interface allows the user to efficiently explore the flow in 3D + real time, fostering an intuitive understanding of steady and unsteady flow patterns. There are obvious extensions to use in an academic setting. The trade-offs between accuracy and speed will be discussed in the context of CFD's role in design and education.

  9. Rapid maxillary anterior teeth retraction en masse by bone compression: a canine model.

    Directory of Open Access Journals (Sweden)

    Chufeng Liu

    Full Text Available OBJECTIVE: The present study sought to establish an animal model to study the feasibility and safety of rapid retraction of maxillary anterior teeth en masse aided by alveolar surgery in order to reduce orthodontic treatment time. METHOD: Extraction of the maxillary canine and alveolar surgery were performed on twelve adult beagle dogs. After that, the custom-made tooth-borne distraction devices were placed on beagles' teeth. Nine of the dogs were applied compression at 0.5 mm/d for 12 days continuously. The other three received no force as the control group. The animals were killed in 1, 14, and 28 days after the end of the application of compression. RESULTS: The tissue responses were assessed by craniometric measurement as well as histological examination. Gross alterations were evident in the experimental group, characterized by anterior teeth crossbite. The average total movements of incisors within 12 days were 4.63±0.10 mm and the average anchorage losses were 1.25±0.12 mm. Considerable root resorption extending into the dentine could be observed 1 and 14 days after the compression. But after consolidation of 28 days, there were regenerated cementum on the dentine. There was no apparent change in the control group. No obvious tooth loosening, gingival necrosis, pulp degeneration, or other adverse complications appeared in any of the dogs. CONCLUSIONS: This is the first experimental study for testing the technique of rapid anterior teeth retraction en masse aided by modified alveolar surgery. Despite a preliminary animal model study, the current findings pave the way for the potential clinical application that can accelerate orthodontic tooth movement without many adverse complications. CLINICAL RELEVANCE: It may become a novel method to shorten the clinical orthodontic treatment time in the future.

  10. Classification of Bacillus and Brevibacillus species using rapid analysis of lipids by mass spectrometry.

    Science.gov (United States)

    AlMasoud, Najla; Xu, Yun; Trivedi, Drupad K; Salivo, Simona; Abban, Tom; Rattray, Nicholas J W; Szula, Ewa; AlRabiah, Haitham; Sayqal, Ali; Goodacre, Royston

    2016-11-01

    Bacillus are aerobic spore-forming bacteria that are known to lead to specific diseases, such as anthrax and food poisoning. This study focuses on the characterization of these bacteria by the detection of lipids extracted from 33 well-characterized strains from the Bacillus and Brevibacillus genera, with the aim to discriminate between the different species. For the purpose of analysing the lipids extracted from these bacterial samples, two rapid physicochemical techniques were used: matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF-MS) and liquid chromatography in conjunction with mass spectrometry (LC-MS). The findings of this investigation confirmed that MALDI-TOF-MS could be used to identify different bacterial lipids and, in combination with appropriate chemometrics, allowed for the discrimination between these different bacterial species, which was supported by LC-MS. The average correct classification rates for the seven species of bacteria were 62.23 and 77.03 % based on MALDI-TOF-MS and LC-MS data, respectively. The Procrustes distance for the two datasets was 0.0699, indicating that the results from the two techniques were very similar. In addition, we also compared these bacterial lipid MALDI-TOF-MS profiles to protein profiles also collected by MALDI-TOF-MS on the same bacteria (Procrustes distance, 0.1006). The level of discrimination between lipids and proteins was equivalent, and this further indicated the potential of MALDI-TOF-MS analysis as a rapid, robust and reliable method for the classification of bacteria based on different bacterial chemical components. Graphical abstract MALDI-MS has been successfully developed for the characterization of bacteria at the subspecies level using lipids and benchmarked against HPLC.

  11. Rapid screening of Alternaria mycotoxins using MALDI-TOF mass spectrometry.

    Science.gov (United States)

    Sivagnanam, Kumaran; Komatsu, Emy; Rampitsch, Christoph; Perreault, Hélène; Gräfenhan, Tom

    2017-01-01

    Members of the Alternaria genus produce various toxins whose occurrence in agricultural commodities is a major concern for humans and the environment. The present study developed a simple and efficient matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) method for the rapid detection of Alternaria toxins. A new method for the detection of alternariol (AOH), alternariol monomethyl ether (AME) and tentoxin (TEN) by MALDI-TOF MS was developed. Different solid phase extraction (SPE) clean-up methods were tried to optimize the purification of wheat matrix, and an optimal extraction method was designed to recover the three Alternaria toxins. In addition, various MALDI matrices were examined and α-cyano-4-hydroxycinnamic acid (CHCA) matrix gave good repeatability for all three Alternaria toxins. This is the first study to report the detection of three important Alternaria toxins concurrently using MALDI-TOF MS and opens up the possibility of rapid screening of Alternaria toxins in several other cereals and food products. © 2016 Her Majesty the Queen in Right of Canada Journal of the Science of Food and Agriculture © 2016 Society of Chemical Industry. © 2016 Her Majesty the Queen in Right of Canada Journal of the Science of Food and Agriculture © 2016 Society of Chemical Industry.

  12. [Rapid determination of volatile organic compounds in workplace air by protable gas chromatography-mass spectrometer].

    Science.gov (United States)

    Zhu, H B; Su, C J; Tang, H F; Ruan, Z; Liu, D H; Wang, H; Qian, Y L

    2017-10-20

    Objective: To establish a method for rapid determination of 47 volatile organic compounds in the air of workplace using portable gas chromatography-mass spectrometer(GC-MS). Methods: The mixed standard gas with different concentration levels was made by using the static gas distribution method with the high purity nitrogen as dilution gas. The samples were injected into the GC-MS by a hand-held probe. Retention time and characteristic ion were used for qualitative analysis,and the internal standard method was usd for quantitation. Results: The 47 poisonous substances were separated and determined well. The linear range of this method was 0.2-16.0 mg/m(3),and the relative standard deviation of 45 volatile ovganic compounds was 3.8%-15.8%. The average recovery was 79.3%-119.0%. Conclusion: The method is simple,accurate,sensitive,has good separation effect,short analysis period, can be used for qualitative and quantitative analysis of volatile organic compounds in the workplace, and also supports the rapid identification and detection of occupational hazards.

  13. [Rapid identification of microorganisms by mass spectrometry in a blood culture system. Comparison of two procedures].

    Science.gov (United States)

    Cattani, María E; Posse, Tamara; Hermes, Ricardo L; Kaufman, Sara C

    2015-01-01

    Rapid identification of microorganisms is critical in hospitalized infected patients. Blood culture is currently the gold standard for detecting and identifying microorganisms causing bacteremia or sepsis. The introduction of mass spectrometry by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF MS) in microbiology laboratories, especially in microorganisms growing in blood culture bottles, provides rapid identification. This study evaluates the performance of the Maldi Sepsityper Biotyper procedure (hereinafter, MS) compared to that of an in-home method (hereinafter, HF). Eight hundred and forty (840) positive blood culture bottles were processed using the HF procedure, 542 of which were also processed using MS. The organisms were identified in 670 (79.76%) and 391 (72.14%) bottles respectively (p = 0,0013). This study demonstrates the effectiveness of both procedures for identifying microorganisms directly from positive blood culture bottles. However, the HF procedure proved to be more effective than MS, especially in the presence of Gram positive organisms. Copyright © 2015 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  14. Rapid determination of uranium isotopes in urine by inductively coupled plasma-mass spectrometry.

    Science.gov (United States)

    Shi, Y; Dai, X; Collins, R; Kramer-Tremblay, S

    2011-08-01

    Following a radiological or nuclear emergency involving uranium exposure, rapid analytical methods are needed to analyze the concentration of uranium isotopes in human urine samples for early dose assessment. The inductively coupled plasma mass spectrometry (ICP-MS) technique, with its high sample throughput and high sensitivity, has advantages over alpha spectrometry for uranium urinalysis after minimum sample preparation. In this work, a rapid sample preparation method using an anion exchange chromatographic column was developed to separate uranium from the urine matrix. A high-resolution sector field ICP-MS instrument, coupled with a high sensitivity desolvation sample introduction inlet, was used to determine uranium isotopes in the samples. The method can analyze up to 24 urine samples in two hours with the limits of detection of 0.0014, 0.10, and 2.0 pg mL(-1) for (234)U, (235)U, and (238)U, respectively, which meet the requirement for isotopic analysis of uranium in a radiation emergency.

  15. Rapid and reliable discrimination between Shigella species and Escherichia coli using MALDI-TOF mass spectrometry.

    Science.gov (United States)

    Paauw, Armand; Jonker, Debby; Roeselers, Guus; Heng, Jonathan M E; Mars-Groenendijk, Roos H; Trip, Hein; Molhoek, E Margo; Jansen, Hugo-Jan; van der Plas, Jan; de Jong, Ad L; Majchrzykiewicz-Koehorst, Joanna A; Speksnijder, Arjen G C L

    2015-01-01

    E. coli-Shigella species are a cryptic group of bacteria in which the Shigella species are distributed within the phylogenetic tree of E. coli. The nomenclature is historically based and the discrimination of these genera developed as a result of the epidemiological need to identify the cause of shigellosis, a severe disease caused by Shigella species. For these reasons, this incorrect classification of shigellae persists to date, and the ability to rapidly characterize E. coli and Shigella species remains highly desirable. Until recently, existing matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) assays used to identify bacteria could not discriminate between E. coli and Shigella species. Here we present a rapid classification method for the E. coli-Shigella phylogroup based on MALDI-TOF MS which is supported by genetic analysis. E. coli and Shigella isolates were collected and genetically characterized by MLVA. A custom reference library for MALDI-TOF MS that represents the genetic diversity of E. coli and Shigella strains was developed. Characterization of E. coli and Shigella species is based on an approach with Biotyper software. Using this reference library it was possible to distinguish between Shigella species and E. coli. Of the 180 isolates tested, 94.4% were correctly classified as E. coli or shigellae. The results of four (2.2%) isolates could not be interpreted and six (3.3%) isolates were classified incorrectly. The custom library extends the existing MALDI-TOF MS method for species determination by enabling rapid and accurate discrimination between Shigella species and E. coli. Copyright © 2015 Elsevier GmbH. All rights reserved.

  16. One Size Fits All Learning Preferences: an Exploration of Rapid Authoring Tools

    Directory of Open Access Journals (Sweden)

    Niav McEvoy

    2013-05-01

    Full Text Available Virtual Learning Environments (VLEs are increasingly being used by colleges and universities to deliver and/or complement traditional face-to-face courses. The range of learning technologies available for use within these virtual platforms is considerable, but how confident are we that these learning tools support the learning process for students? It is crucial that the learning tools utilised in virtual platforms do not cause additional barriers for the online and distant learner. This Survey research study is designed to determine if rapid authoring tools can meet the needs of a variety of learning preferences of adult learners. The study focuses specifically on the use of virtual tutorials, created using the rapid authoring tool Articulate Presenter 2007, to establish the learning preferences of the students as represented by Fleming's (2011 VARK model. In total, ten variations of the VARK learning preferences were represented across respondents, with the majority indicating a uni-modal preference in an online self-administered questionnaire. Overall, the majority of students responded positively in relation to their experience of the virtual tutorial.

  17. Mass Spectral Profile for Rapid Differentiating Beta-Lactams from Their Ring-Opened Impurities

    Directory of Open Access Journals (Sweden)

    Hecheng Wang

    2015-01-01

    Full Text Available High performance liquid chromatography tandem mass spectrometry (HPLC MS has been widely used for β-lactam antibiotics determination. However, its application to identify impurities of these frequently used drugs is not sufficient at present. In this job, characteristic profiles of the collision induced dissociation (CID spectra of both β-lactams and ring-opened β-lactams were extracted from the MS data of six β-lactam antibiotics and their forty-five impurities, and were confirmed by the MS data reported in the literature. These characteristics have been successfully applied to rapid differentiation of β-lactam and ring-opened β-lactam impurities in cefixime, cefdinir, and cefaclor. However, these characteristic profiles can only be obtained under low activating voltage. They did not display in the high energy activated CID spectra. Diagnostic fragmentations for determining the localization of double bond and substituents on the thiazine ring and the side chain were also observed. In addition, several characteristic fragmentations are hopeful to be used to differentiate the configurations of C-2 on the thiazine ring of ring-opened impurities, which is generally disadvantageous of mass spectrometry. Taken together, forty-five impurities were identified from the capsules of cefixime, cefdinir, and cefaclor.

  18. The Formation of Rapidly Rotating Black Holes in High-mass X-Ray Binaries

    Science.gov (United States)

    Batta, Aldo; Ramirez-Ruiz, Enrico; Fryer, Chris

    2017-09-01

    High-mass X-ray binaries (HMXRBs), such as Cygnus X-1, host some of the most rapidly spinning black holes (BHs) known to date, reaching spin parameters a≳ 0.84. However, there are several effects that can severely limit the maximum BH spin parameter that could be obtained from direct collapse, such as tidal synchronization, magnetic core-envelope coupling, and mass loss. Here, we propose an alternative scenario where the BH is produced by a failed supernova (SN) explosion that is unable to unbind the stellar progenitor. A large amount of fallback material ensues, whose interaction with the secondary naturally increases its overall angular momentum content, and therefore the spin of the BH when accreted. Through SPH hydrodynamic simulations, we studied the unsuccessful explosion of an 8 {M}⊙ pre-SN star in a close binary with a 12 {M}⊙ companion with an orbital period of ≈1.2 days, finding that it is possible to obtain a BH with a high spin parameter a≳ 0.8 even when the expected spin parameter from direct collapse is a≲ 0.3. This scenario also naturally explains the atmospheric metal pollution observed in HMXRB stellar companions.

  19. Mass Housing Using GFRG Panels: A Sustainable, Rapid and Affordable Solution

    Science.gov (United States)

    Cherian, Philip; Paul, Shinto; Krishna, S. R. Gouri; Menon, Devdas; Meher Prasad, A.

    2017-06-01

    This work gives an overview of research and development carried out at IIT Madras, using glass fibre reinforced gypsum (GFRG) panels, to provide an innovative solution for rapid and affordable mass housing. The GFRG panels (124 mm thick), made from recycled industrial waste gypsum (from the fertilizer industry), are prefabricated in 3 m × 12 m sizes with cellular cavities inside, which can be filled with reinforced concrete wherever required and can be used as walls as well as floor slabs. The tests carried out (over the past 12 years) establish the performance of GFRG building systems to resist gravity and lateral loads as a load-bearing system (without beams and columns) in multi-storeyed buildings up to 8-10 storeys, with adequate strength, serviceability, durability and ductility. A two-storeyed four-apartment demonstration building has also been successfully constructed in the IIT Madras campus and presently a mass housing scheme (40 apartment units) using this technology is being demonstrated at Nellore. A structural design code has also been approved by the Bureau of Indian Standards, based on the extensive studies carried out on GFRG building systems.

  20. A Rapid Auto-Indexing Technology for Designing Readable E-Learning Content

    Science.gov (United States)

    Yu, Pao-Ta; Liao, Yuan-Hsun; Su, Ming-Hsiang; Cheng, Po-Jen; Pai, Chun-Hsuan

    2012-01-01

    A rapid scene indexing method is proposed to improve retrieval performance for students accessing instructional videos. This indexing method is applied to anchor suitable indices to the instructional video so that students can obtain several small lesson units to gain learning mastery. The method also regulates online course progress. These…

  1. Rapid E-learning Development Strategies and a Multimedia Project Design Model

    Science.gov (United States)

    Sözcü, Ömer Faruk; Ipek, Ismail

    2014-01-01

    The purpose of the study is to discuss e-learning design strategies which can be used for multimedia projects as a design model. Recent advances in instructional technologies have been found to be very important in the design of training courses by using rapid instructional design (ID) approaches. The approaches were developed to use in training…

  2. ACUTE EFFECTS OF SELF-SELECTED REGIMEN OF RAPID BODY MASS LOSS IN COMBAT SPORTS ATHLETES

    Directory of Open Access Journals (Sweden)

    Jaan Ereline

    2008-06-01

    Full Text Available The purpose of the study was to assess the acute effects of the self-selected regimen of rapid body mass loss (RBML on muscle performance and metabolic response to exercise in combat sports athletes. Seventeen male athletes (20.8 ± 1.0 years; mean ± SD reduced their body mass by 5.1 ± 1.1% within 3 days. The RBML was achieved by a gradual reduction of energy and fluid intake and mild sauna procedures. A battery of tests was performed before (Test 1 and immediately after (Test 2 RBML. The test battery included the measurement of the peak torque of knee extensors for three different speeds, assessment of total work (Wtot performed during a 3-min intermittent intensity knee extension exercise and measurements of blood metabolites (ammonia, lactate, glucose and urea. Absolute peak torque was lower in Test 2 compared with Test 1 at angular velocities of 1.57 rad·s-1 (218.6 ± 40.9 vs. 234.4 ± 42.2 N·m; p = 0.013 and 3.14 rad·s-1 (100.3 ± 27.8 vs. 111.7 ± 26.2 N·m; p = 0.008. The peak torque in relation to body mass remained unchanged for any speed. Absolute Wtot was lower in Test 2 compared with Test 1 (6359 ± 2326 vs. 7452 ± 3080 J; p = 0.003 as well as Wtot in relation to body mass (89.1 ± 29.9 vs. 98.6 ± 36.4 J·kg-1; p = 0.034, respectively. As a result of RBML, plasma urea concentration increased from 4.9 to 5.9 mmol·l-1 (p = 0.003. The concentration of ammonia in a post-test sample in Test 2 tended to be higher in comparison with Test 1 (80.9 ± 29.1 vs. 67.6 ± 26.5 mmol·l-1; p = 0.082. The plasma lactate and glucose responses to exercise were similar in Test 1 and Test 2. We conclude that the self-selected regimen of RBML impairs muscle performance in 3-min intermittent intensity exercise and induces an increase in blood urea concentration in experienced male combat sports athletes

  3. ADVANTAGES OF RAPID METHOD FOR DETERMINING SCALE MASS AND DECARBURIZED LAYER OF ROLLED COIL STEEL

    Directory of Open Access Journals (Sweden)

    E. V. Parusov

    2016-08-01

    Full Text Available Purpose. To determine the universal empirical relationships that allow for operational calculation of scale mass and decarbonized layer depth based on the parameters of the technological process for rolled coil steel production. Methodology. The research is carried out on the industrial batches of the rolled steel of SAE 1006 and SAE 1065 grades. Scale removability was determined in accordance with the procedure of «Bekaert» company by the specifi-cations: GA-03-16, GA-03-18, GS-03-02, GS-06-01. The depth of decarbonized layer was identified in accordance with GOST 1763-68 (M method. Findings. Analysis of experimental data allowed us to determine the rational temperature of coil formation of the investigated steel grades, which provide the best possible removal of scale from the metal surface, a minimal amount of scale, as well as compliance of the metal surface color with the require-ments of European consumers. Originality. The work allowed establishing correlation of the basic quality indicators of the rolled coil high carbon steel (scale mass, depth of decarbonized layer and inter-laminar distance in pearlite with one of the main parameters (coil formation temperature of the deformation and heat treatment mode. The re-sulting regression equations, without metallographic analysis, can be used to determine, with a minimum error, the quantitative values of the total scale mass, depth of decarbonized layer and the average inter-lamellar distance in pearlite of the rolled coil high carbon steel. Practical value. Based on the specifications of «Bekaert» company (GA-03-16, GA-03-18, GS-03-02 and GS-06-01 the method of testing descaling by mechanical means from the surface of the rolled coil steel of low- and high-carbon steel grades was developed and approved in the environment of PJSC «ArcelorMittal Kryvyi Rih». The work resulted in development of the rapid method for determination of total and remaining scale mass on the rolled coil steel

  4. Perceptual learning of time-compressed speech: more than rapid adaptation.

    Science.gov (United States)

    Banai, Karen; Lavner, Yizhar

    2012-01-01

    Time-compressed speech, a form of rapidly presented speech, is harder to comprehend than natural speech, especially for non-native speakers. Although it is possible to adapt to time-compressed speech after a brief exposure, it is not known whether additional perceptual learning occurs with further practice. Here, we ask whether multiday training on time-compressed speech yields more learning than that observed during the initial adaptation phase and whether the pattern of generalization following successful learning is different than that observed with initial adaptation only. Two groups of non-native Hebrew speakers were tested on five different conditions of time-compressed speech identification in two assessments conducted 10-14 days apart. Between those assessments, one group of listeners received five practice sessions on one of the time-compressed conditions. Between the two assessments, trained listeners improved significantly more than untrained listeners on the trained condition. Furthermore, the trained group generalized its learning to two untrained conditions in which different talkers presented the trained speech materials. In addition, when the performance of the non-native speakers was compared to that of a group of naïve native Hebrew speakers, performance of the trained group was equivalent to that of the native speakers on all conditions on which learning occurred, whereas performance of the untrained non-native listeners was substantially poorer. Multiday training on time-compressed speech results in significantly more perceptual learning than brief adaptation. Compared to previous studies of adaptation, the training induced learning is more stimulus specific. Taken together, the perceptual learning of time-compressed speech appears to progress from an initial, rapid adaptation phase to a subsequent prolonged and more stimulus specific phase. These findings are consistent with the predictions of the Reverse Hierarchy Theory of perceptual

  5. FROM TRADITIONAL DISTANCE LEARNING TO MASS ONLINE OPEN COURSES

    Directory of Open Access Journals (Sweden)

    V. N. Vasilev

    2014-01-01

    Full Text Available The issue of transition for higher education institutions of Russia from traditional distance learning to mass electronic education on the basis of the online open courses is considered, its relevance is proved. Analysis of the major prerequisites for transition success is carried out (a demand for the educational Internet resources from mobile devices; existence of a large number of various electronic resources which are successfully used in practice by higher education institutions in remote educational technologies; maintaining experience for electronic magazines of students’ progress for planning and estimation of training results; essential growth of material costs in the world online training market. Key issues of transition are defined and the basic principles of electronic online courses development are formulated. A technique for electronic online course development aimed at the result is given. The technique contains the following four stages: planning of expected training results, course electronic content structuring and training scenarios creation, development of the tests plan and electronic estimated means for automatic control of the planned training results; course realization by means of game mechanics and technologies of network communication between students. Requirements to various forms of control planned in the course of learning results are defined. Two kinds of electronic online courses are assigned (knowledge-intensive and technological courses. Examples of their realization in the authors’ online courses "Wave Optics", "Theory of Graphs ", "Development of Web Interfaces on the Basis of HTML and CSS" created and practically used in NRU ITMO in 2013 are given. Finally, the actual tasks of mass open education development in the leading higher education institutions of Russia are set forth.

  6. Rapid quality assessment of Radix Aconiti Preparata using direct analysis in real time mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Zhu Hongbin; Wang Chunyan; Qi Yao [Changchun Center of Mass Spectrometry and Chemical Biology Laboratory, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); University of Chinese Academy of Sciences, Beijing 100039 (China); Song Fengrui, E-mail: songfr@ciac.jl.cn [Changchun Center of Mass Spectrometry and Chemical Biology Laboratory, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Liu Zhiqiang; Liu Shuying [Changchun Center of Mass Spectrometry and Chemical Biology Laboratory, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China)

    2012-11-08

    Highlights: Black-Right-Pointing-Pointer DART MS combined with PCA and HCA was used to rapidly identify markers of Radix Aconiti. Black-Right-Pointing-Pointer The DART MS behavior of six aconitine-type alkaloids was investigated. Black-Right-Pointing-Pointer Chemical markers were recognized between the qualified and unqualified samples. Black-Right-Pointing-Pointer DART MS was shown to be an effective tool for quality control of Radix Aconiti Preparata. - Abstract: This study presents a novel and rapid method to identify chemical markers for the quality control of Radix Aconiti Preparata, a world widely used traditional herbal medicine. In the method, the samples with a fast extraction procedure were analyzed using direct analysis in real time mass spectrometry (DART MS) combined with multivariate data analysis. At present, the quality assessment approach of Radix Aconiti Preparata was based on the two processing methods recorded in Chinese Pharmacopoeia for the purpose of reducing the toxicity of Radix Aconiti and ensuring its clinical therapeutic efficacy. In order to ensure the safety and effectivity in clinical use, the processing degree of Radix Aconiti should be well controlled and assessed. In the paper, hierarchical cluster analysis and principal component analysis were performed to evaluate the DART MS data of Radix Aconiti Preparata samples in different processing times. The results showed that the well processed Radix Aconiti Preparata, unqualified processed and the raw Radix Aconiti could be clustered reasonably corresponding to their constituents. The loading plot shows that the main chemical markers having the most influence on the discrimination amongst the qualified and unqualified samples were mainly some monoester diterpenoid aconitines and diester diterpenoid aconitines, i.e. benzoylmesaconine, hypaconitine, mesaconitine, neoline, benzoylhypaconine, benzoylaconine, fuziline, aconitine and 10-OH-mesaconitine. The established DART MS approach in

  7. MALDI-TOF mass spectrometry for the rapid identification of aetiological agents of sepsis

    Directory of Open Access Journals (Sweden)

    Roberto Degl’Innocenti

    2013-04-01

    Full Text Available Introduction: The MALDI-TOF has recently become part of the methods of microbiological investigation in many laboratories of bacteriology with advantages both practical and economical.The use of this technique for the rapid identification of the causative agents of sepsis is of strategic importance to the ability to provide the clinician with useful information for a prompt and rapid establishment of an empirical antimicrobial “targeted” therapy. Methods: It was tested a total of 343 positive blood culture bottles from 211 patients. The samples after collection were incubated in the BACTEC FX (Becton Dickinson, USA. From these bottles were taken a few milliliters of broth culture and transferred into a vacutainer tube containing gel. This was centrifuged, the supernatant was decanted, and finally recovered the bacterial suspension on the gel. With micro-organisms recovered in this way, after several washes with distilled water, was prepared a slide for microscopic examination with Gram stain, and a plate for mass spectrometry (MS-Vitek, bioMérieux, France.Then, the same samples were inoculated on solid agar media according to the protocol in use in our laboratory.The next day was checked the possible bacterial growth on solid media; we then proceeded to the identification of the colonies by Vitek MS and / or with the system Vitek2 (bioMérieux, France. Results: 258 (75.2% positive vials show concordant results between direct identification and identification after growth on agar. For 83 (24.2% positive bottles there has been full compliance with the microscopic examination but not with culture. In particular, two bottles (0.6% have given complete discordance between the direct identification and that after growth. Conclusions: The protocol we use for the direct identification of organisms responsible for sepsis, directly on positive bottles, seems to be a quick and inexpensive procedure, which in less than 60 minutes can give valuable

  8. A real time metabolomic profiling approach to detecting fish fraud using rapid evaporative ionisation mass spectrometry.

    Science.gov (United States)

    Black, Connor; Chevallier, Olivier P; Haughey, Simon A; Balog, Julia; Stead, Sara; Pringle, Steven D; Riina, Maria V; Martucci, Francesca; Acutis, Pier L; Morris, Mike; Nikolopoulos, Dimitrios S; Takats, Zoltan; Elliott, Christopher T

    2017-01-01

    Fish fraud detection is mainly carried out using a genomic profiling approach requiring long and complex sample preparations and assay running times. Rapid evaporative ionisation mass spectrometry (REIMS) can circumvent these issues without sacrificing a loss in the quality of results. To demonstrate that REIMS can be used as a fast profiling technique capable of achieving accurate species identification without the need for any sample preparation. Additionally, we wanted to demonstrate that other aspects of fish fraud other than speciation are detectable using REIMS. 478 samples of five different white fish species were subjected to REIMS analysis using an electrosurgical knife. Each sample was cut 8-12 times with each one lasting 3-5 s and chemometric models were generated based on the mass range m/z 600-950 of each sample. The identification of 99 validation samples provided a 98.99% correct classification in which species identification was obtained near-instantaneously (≈ 2 s) unlike any other form of food fraud analysis. Significant time comparisons between REIMS and polymerase chain reaction (PCR) were observed when analysing 6 mislabelled samples demonstrating how REIMS can be used as a complimentary technique to detect fish fraud. Additionally, we have demonstrated that the catch method of fish products is capable of detection using REIMS, a concept never previously reported. REIMS has been proven to be an innovative technique to help aid the detection of fish fraud and has the potential to be utilised by fisheries to conduct their own quality control (QC) checks for fast accurate results.

  9. Rapid Mass Spectrometric Analysis of a Novel Fucoidan, Extracted from the Brown Alga Coccophora langsdorfii

    Directory of Open Access Journals (Sweden)

    Stanislav D. Anastyuk

    2014-01-01

    Full Text Available The novel highly sulfated (35% fucoidan fraction Cf2 , which contained, along with fucose, galactose and traces of xylose and uronic acids was purified from the brown alga Coccophora langsdorfii. Its structural features were predominantly determined (in comparison with fragments of known structure by a rapid mass spectrometric investigation of the low-molecular-weight fragments, obtained by “mild” (5 mg/mL and “exhaustive” (maximal concentration autohydrolysis. Tandem matrix-assisted laser desorption/ionization mass spectra (MALDI-TOF/TOFMS of fucooligosaccharides with even degree of polymerization (DP, obtained by “mild” autohydrolysis, were the same as that observed for fucoidan from Fucus evanescens, which have a backbone of alternating (1 → 3- and (1 → 4 linked sulfated at C-2 and sometimes at C-4 of 3-linked α-L-Fucp residues. Fragmentation patterns of oligosaccharides with odd DP indicated sulfation at C-2 and at C-4 of (1 → 3 linked α-L-Fucp residues on the reducing terminus. Minor sulfation at C-3 was also suggested. The “exhaustive” autohydrolysis allowed us to observe the “mixed” oligosaccharides, built up of fucose/xylose and fucose/galactose. Xylose residues were found to occupy both the reducing and nonreducing termini of FucXyl disaccharides. Nonreducing galactose residues as part of GalFuc disaccharides were found to be linked, possibly, by 2-type of linkage to fucose residues and were found to be sulfated, most likely, at position C-2.

  10. Rapid quantification of ionophores in feeds by liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Huang, Min; Rumbeiha, Wilson K; Braselton, W Emmett; Johnson, Margaret

    2011-09-01

    Ionophores are widely used in veterinary medicine as coccidiostats and for improving nutrient utilization in livestock production. Because of widespread use, ionophores sometimes cause poisoning in livestock. Quantifying concentration of these compounds in feeds for diagnostic purposes is needed. A method with a single step of solvent extraction was developed for rapid simultaneous quantification of monensin, lasalocid, salinomycin, and narasin in feeds by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The ionophores were extracted using methanol:water (90:10). With the high specificity and high sensitivity of tandem mass spectrometry, the extract was introduced for measurement without further processing. The effect of particle size of feeds on extraction efficiency was also investigated. It was found that feeds passing through a 1-mm filter or sieve show better quantitative extraction. Nigericin was used as internal standard for the measurement. The method was validated by fortification of the selected ionophore compounds in horse feed at different concentrations. The typical recovery rate was 69-122%. Meanwhile, various interlaboratory proficiency test samples of different matrices were also quantified as part of the procedure for method validation. A good agreement was found between results and the suggested values. The method is very sensitive, with detection limits between 0.018 µg/g and 0.056 µg/g for the compounds tested. Results showed that the lower limit of quantification was 0.2 µg/g for the ionophore compounds, which is much lower than the contents of the ionophores in medicated feeds, which is generally approximately 10-100 µg/g feed.

  11. Rapid screening of clenbuterol in urine samples by desorption electrospray ionization tandem mass spectrometry.

    Science.gov (United States)

    Lin, Ziqing; Zhang, Sichun; Zhao, Mengxia; Yang, Chengdui; Chen, Depu; Zhang, Xinrong

    2008-06-01

    Rapid screening of clenbuterol in urine was performed by combining desorption electrospray ionization (DESI) and tandem mass spectrometry (MS/MS). Optimization experiments were carried out including the selection of substrates, spray solutions, nebulizing gas pressures, high-voltage power supplies and flow rates of spray solution. The limit of detection (LOD), defined as the lowest quantity that can be detected, was 5.0 pg for the pure compound. Using DESI coupled with solid-phase extraction (SPE), the linear response range was from 10 to 400 ng/mL (R(2) = 0.993) and the concentration LOD for urine sample was 2.0 ng/mL. The analysis for one spiked urine sample was achieved within 4 min. In addition to the fast analysis speed, MS/MS provided structural information for the confirmation of clenbuterol. Urine samples from different people were investigated and the recoveries were within 100 +/- 20%. The developed method can potentially be used for screening of clenbuterol in doping control.

  12. Rapid and high-throughput pan-Orthopoxvirus detection and identification using PCR and mass spectrometry.

    Directory of Open Access Journals (Sweden)

    Mark W Eshoo

    2009-07-01

    Full Text Available The genus Orthopoxvirus contains several species of related viruses, including the causative agent of smallpox (Variola virus. In addition to smallpox, several other members of the genus are capable of causing human infection, including monkeypox, cowpox, and other zoonotic rodent-borne poxviruses. Therefore, a single assay that can accurately identify all orthopoxviruses could provide a valuable tool for rapid broad orthopovirus identification. We have developed a pan-Orthopoxvirus assay for identification of all members of the genus based on four PCR reactions targeting Orthopoxvirus DNA and RNA helicase and polymerase genes. The amplicons are detected using electrospray ionization-mass spectrometry (PCR/ESI-MS on the Ibis T5000 system. We demonstrate that the assay can detect and identify a diverse collection of orthopoxviruses, provide sub-species information and characterize viruses from the blood of rabbitpox infected rabbits. The assay is sensitive at the stochastic limit of PCR and detected virus in blood containing approximately six plaque-forming units per milliliter from a rabbitpox virus-infected rabbit.

  13. Adjustment to Subtle Time Constraints and Power Law Learning in Rapid Serial Visual Presentation.

    Science.gov (United States)

    Shin, Jacqueline C; Chang, Seah; Cho, Yang Seok

    2015-01-01

    We investigated whether attention could be modulated through the implicit learning of temporal information in a rapid serial visual presentation (RSVP) task. Participants identified two target letters among numeral distractors. The stimulus-onset asynchrony immediately following the first target (SOA1) varied at three levels (70, 98, and 126 ms) randomly between trials or fixed within blocks of trials. Practice over 3 consecutive days resulted in a continuous improvement in the identification rate for both targets and attenuation of the attentional blink (AB), a decrement in target (T2) identification when presented 200-400 ms after another target (T1). Blocked SOA1s led to a faster rate of improvement in RSVP performance and more target order reversals relative to random SOA1s, suggesting that the implicit learning of SOA1 positively affected performance. The results also reveal "power law" learning curves for individual target identification as well as the reduction in the AB decrement. These learning curves reflect the spontaneous emergence of skill through subtle attentional modulations rather than general attentional distribution. Together, the results indicate that implicit temporal learning could improve high level and rapid cognitive processing and highlights the sensitivity and adaptability of the attentional system to subtle constraints in stimulus timing.

  14. Adjustment to subtle time constraints and power law learning in rapid serial visual presentation

    Directory of Open Access Journals (Sweden)

    Jacqueline Chakyung Shin

    2015-11-01

    Full Text Available We investigated whether attention could be modulated through the implicit learning of temporal information in a rapid serial visual presentation (RSVP task. Participants identified two target letters among numeral distractors. The stimulus-onset asynchrony immediately following the first target (SOA1 varied at three levels (70, 98, and 126 ms randomly between trials or fixed within blocks of trials. Practice over three consecutive days resulted in a continuous improvement in the identification rate for both targets and attenuation of the attentional blink (AB, a decrement in target (T2 identification when presented 200-400 ms after another target (T1. Blocked SOA1s led to a faster rate of improvement in RSVP performance and more target order reversals relative to random SOA1s, suggesting that the implicit learning of SOA1 positively affected performance. The results also reveal power law learning curves for individual target identification as well as the reduction in the AB decrement. These learning curves reflect the spontaneous emergence of skill through subtle attentional modulations rather than general attentional distribution. Together, the results indicate that implicit temporal learning could improve high level and rapid cognitive processing and highlights the sensitivity and adaptability of the attentional system to subtle constraints in stimulus timing.

  15. Potential of short-column liquid chromatographia with tandem mass spectrometric detection for the rapid study of pesticide degradation

    NARCIS (Netherlands)

    Hogenboom, A.C.; Steen, R.J.C.A.; Niessen, W.M.A.; Brinkman, U.A.T.

    1998-01-01

    The applicability of solid-phase extraction-LC using two short columns (SPE-LC) and/or single-short-column liquid chromatography (SSC) combined on- line with tandem mass spectrometry (MS) was demonstrated for the rapid study of pesticide degradation. A fast analytical procedure was developed to

  16. Toward Automating HIV Identification: Machine Learning for Rapid Identification of HIV-Related Social Media Data.

    Science.gov (United States)

    Young, Sean D; Yu, Wenchao; Wang, Wei

    2017-02-01

    "Social big data" from technologies such as social media, wearable devices, and online searches continue to grow and can be used as tools for HIV research. Although researchers can uncover patterns and insights associated with HIV trends and transmission, the review process is time consuming and resource intensive. Machine learning methods derived from computer science might be used to assist HIV domain experts by learning how to rapidly and accurately identify patterns associated with HIV from a large set of social data. Using an existing social media data set that was associated with HIV and coded by an HIV domain expert, we tested whether 4 commonly used machine learning methods could learn the patterns associated with HIV risk behavior. We used the 10-fold cross-validation method to examine the speed and accuracy of these models in applying that knowledge to detect HIV content in social media data. Logistic regression and random forest resulted in the highest accuracy in detecting HIV-related social data (85.3%), whereas the Ridge Regression Classifier resulted in the lowest accuracy. Logistic regression yielded the fastest processing time (16.98 seconds). Machine learning can enable social big data to become a new and important tool in HIV research, helping to create a new field of "digital HIV epidemiology." If a domain expert can identify patterns in social data associated with HIV risk or HIV transmission, machine learning models could quickly and accurately learn those associations and identify potential HIV patterns in large social data sets.

  17. A flexible mechanism of rule selection enables rapid feature-based reinforcement learning

    Directory of Open Access Journals (Sweden)

    Matthew eBalcarras

    2016-03-01

    Full Text Available Learning in a new environment is influenced by prior learning and experience. Correctly applying a rule that maps a context to stimuli, actions, and outcomes enables faster learning and better outcomes compared to relying on strategies for learning that are ignorant of task structure. However, it is often difficult to know when and how to apply learned rules in new contexts. In our study we explored how subjects employ different strategies for learning the relationship between stimulus features and positive outcomes in a probabilistic task context. We test the hypothesis that task naive subjects will show enhanced learning of feature specific reward associations by switching to the use of an abstract rule that associates stimuli by feature type and restricts selections to that dimension. To test this hypothesis we designed a decision making task where subjects receive probabilistic feedback following choices between pairs of stimuli. In the task, trials are grouped in two contexts by blocks, where in one type of block there is no unique relationship between a specific feature dimension (stimulus shape or colour and positive outcomes, and following an un-cued transition, alternating blocks have outcomes that are linked to either stimulus shape or colour. Two-thirds of subjects (n=22/32 exhibited behaviour that was best fit by a hierarchical feature-rule model. Supporting the prediction of the model mechanism these subjects showed significantly enhanced performance in feature-reward blocks, and rapidly switched their choice strategy to using abstract feature rules when reward contingencies changed. Choice behaviour of other subjects (n=10/32 was fit by a range of alternative reinforcement learning models representing strategies that do not benefit from applying previously learned rules. In summary, these results show that untrained subjects are capable of flexibly shifting between behavioural rules by leveraging simple model-free reinforcement

  18. Rapid detection of undesired cosmetic ingredients by matrix-assisted laser desorption ionization time-of-flight mass spectrometry.

    Science.gov (United States)

    Ouyang, Jie; An, Dongli; Chen, Tengteng; Lin, Zhiwei

    2017-10-01

    In recent years, cosmetic industry profits soared due to the widespread use of cosmetics, which resulted in illicit manufacturers and products of poor quality. Therefore, the rapid and accurate detection of the composition of cosmetics has become crucial. At present, numerous methods, such as gas chromatography and liquid chromatography-mass spectrometry, were available for the analysis of cosmetic ingredients. However, these methods present several limitations, such as failure to perform comprehensive and rapid analysis of the samples. Compared with other techniques, matrix-assisted laser desorption ionization time-of-flight mass spectrometry offered the advantages of wide detection range, fast speed and high accuracy. In this article, we briefly summarized how to select a suitable matrix and adjust the appropriate laser energy. We also discussed the rapid identification of undesired ingredients, focusing on antibiotics and hormones in cosmetics.

  19. Urban Air Pollution in Taiwan before and after the Installation of a Mass Rapid Transit System.

    Science.gov (United States)

    Ding, Pei-Hsiou; Wang, Gen-Shuh; Chen, Bing-Yu; Wan, Gwo-Hwa

    2016-09-01

    Urbanization causes air pollution in metropolitan areas, coupled with meteorological factors that affect air quality. Although previous studies focused on the relationships of urbanization, air pollution, and climate change in Western countries, this study evaluated long-term variations of air quality and meteorological factors in Taiwanese metropolitan areas (Taipei area, Taichung City, and Kaohsiung City) and a rural area (Hualien County) between 1993 and 2012. The influence of a mass rapid transit (MRT) system on air quality was also evaluated. Air pollutant concentrations and meteorology data were collected from Taiwan Environmental Protection Administration (TEPA) air monitoring stations and Central Weather Bureau stations in the surveyed areas, respectively. Analyses indicate that levels of air pollution in metropolitan areas were greater than in the rural area. Kaohsiung City had the highest levels of O, SO, and particulate matter 2.5 or 10 µm in diameter (PM and PM). Clear downward trends for CO, NO, PM, PM, and especially SO concentrations were found in the surveyed areas, whereas O showed no decrease. Both O and PM concentrations showed similar bimodal seasonal distributions. Taiwan's air quality has improved significantly since 1993, indicating the effectiveness of promoting air pollution strategies and policies by the TEPA. Air pollution had an obvious improvement in Taipei area after the MRT system began operations in 1996. Because global climate may potentially affect urban air pollution in Taiwan, further study to clarify the mechanisms by which air pollution may affect human health and other biological effects is warranted. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  20. Modular Rapid E-Learning Framework (MORELF) in Desktop Virtualization Environment: An Effective Hybrid Implementation in Nurse Education

    Science.gov (United States)

    Parlakkilic, Alattin

    2015-01-01

    Generally it is not easy for an instructor to prepare and deliver electronic courses via e-learning. Therefore it is necessary to work and develop an easy system. In this context module technology was used to for provide modularity in conducting educational development of e-learning course. Then, rapid e-learning was used for more quick and easy…

  1. MASS MEDIA AND ENGLISH LEARNING ACTIVITY IN BLITAR INDONESIA

    OpenAIRE

    Abdul Aziz

    2016-01-01

    This study is intended to know how English teachers in MTsN Selorejo, Blitar employ variety of English learning sources and implement English learning activity relevant to student’s learning preference in order to create joyful and conducive atmosphere of English learning activity to achieve the learning target better. The researcher uses qualitative method to conduct the study. The researcher analyzes the qualitative data from interview and observation in order to describe the phenomena. The...

  2. Knowledge bases, clinical decision support systems, and rapid learning in oncology.

    Science.gov (United States)

    Yu, Peter Paul

    2015-03-01

    One of the most important benefits of health information technology is to assist the cognitive process of the human mind in the face of vast amounts of health data, limited time for decision making, and the complexity of the patient with cancer. Clinical decision support tools are frequently cited as a technologic solution to this problem, but to date useful clinical decision support systems (CDSS) have been limited in utility and implementation. This article describes three unique sources of health data that underlie fundamentally different types of knowledge bases which feed into CDSS. CDSS themselves comprise a variety of models which are discussed. The relationship of knowledge bases and CDSS to rapid learning health systems design is critical as CDSS are essential drivers of rapid learning in clinical care. Copyright © 2015 by American Society of Clinical Oncology.

  3. Learning through policy tourism: circulating bus rapid transit from South America to South Africa

    OpenAIRE

    Astrid Wood

    2014-01-01

    Study tours, a form of ‘policy tourism’ in which local actors travel elsewhere to see best practice and meet with those in the exporting locality who implemented it, have become a basic tenet for policy exchange. In the pursuit of these lessons, hundreds of South African public transport enthusiasts visited South America, particularly Bogota, to learn of its thriving bus rapid transit (BRT) network. This paper evaluates the influence of these exchanges on BRT circulation and adoption—what tak...

  4. Hippocampal size predicts rapid learning of a cognitive map in humans.

    Science.gov (United States)

    Schinazi, Victor R; Nardi, Daniele; Newcombe, Nora S; Shipley, Thomas F; Epstein, Russell A

    2013-06-01

    The idea that humans use flexible map-like representations of their environment to guide spatial navigation has a long and controversial history. One reason for this enduring controversy might be that individuals vary considerably in their ability to form and utilize cognitive maps. Here we investigate the behavioral and neuroanatomical signatures of these individual differences. Participants learned an unfamiliar campus environment over a period of three weeks. In their first visit, they learned the position of different buildings along two routes in separate areas of the campus. During the following weeks, they learned these routes for a second and third time, along with two paths that connected both areas of the campus. Behavioral assessments after each learning session indicated that subjects formed a coherent representation of the spatial structure of the entire campus after learning a single connecting path. Volumetric analyses of structural MRI data and voxel-based morphometry (VBM) indicated that the size of the right posterior hippocampus predicted the ability to use this spatial knowledge to make inferences about the relative positions of different buildings on the campus. An inverse relationship between gray matter volume and performance was observed in the caudate. These results suggest that (i) humans can rapidly acquire cognitive maps of large-scale environments and (ii) individual differences in hippocampal anatomy may provide the neuroanatomical substrate for individual differences in the ability to learn and flexibly use these cognitive maps. © 2013 Wiley Periodicals, Inc. Copyright © 2013 Wiley Periodicals, Inc.

  5. Rapid Associative Learning and Stable Long-Term Memory in the Squid Euprymna scolopes.

    Science.gov (United States)

    Zepeda, Emily A; Veline, Robert J; Crook, Robyn J

    2017-06-01

    Learning and memory in cephalopod molluscs have received intensive study because of cephalopods' complex behavioral repertoire and relatively accessible nervous systems. While most of this research has been conducted using octopus and cuttlefish species, there has been relatively little work on squid. Euprymna scolopes Berry, 1913, a sepiolid squid, is a promising model for further exploration of cephalopod cognition. These small squid have been studied in detail for their symbiotic relationship with bioluminescent bacteria, and their short generation time and successful captive breeding through multiple generations make them appealing models for neurobiological research. However, little is known about their behavior or cognitive ability. Using the well-established "prawn-in-the-tube" assay of learning and memory, we show that within a single 10-min trial E. scolopes learns to inhibit its predatory behavior, and after three trials it can retain this memory for at least 12 d. Rapid learning and very long-term retention were apparent under two different training schedules. To our knowledge, this study is the first demonstration of learning and memory in this species as well as the first demonstration of associative learning in any squid.

  6. Rapid High-throughput Species Identification of Botanical Material Using Direct Analysis in Real Time High Resolution Mass Spectrometry.

    Science.gov (United States)

    Lesiak, Ashton D; Musah, Rabi A

    2016-10-02

    We demonstrate that direct analysis in real time-high resolution mass spectrometry can be used to produce mass spectral profiles of botanical material, and that these chemical fingerprints can be used for plant species identification. The mass spectral data can be acquired rapidly and in a high throughput manner without the need for sample extraction, derivatization or pH adjustment steps. The use of this technique bypasses challenges presented by more conventional techniques including lengthy chromatography analysis times and resource intensive methods. The high throughput capabilities of the direct analysis in real time-high resolution mass spectrometry protocol, coupled with multivariate statistical analysis processing of the data, provide not only class characterization of plants, but also yield species and varietal information. Here, the technique is demonstrated with two psychoactive plant products, Mitragyna speciosa (Kratom) and Datura (Jimsonweed), which were subjected to direct analysis in real time-high resolution mass spectrometry followed by statistical analysis processing of the mass spectral data. The application of these tools in tandem enabled the plant materials to be rapidly identified at the level of variety and species.

  7. Rapid Evaporative Ionisation Mass Spectrometry (REIMS) Provides Accurate Direct from Culture Species Identification within the Genus Candida.

    Science.gov (United States)

    Cameron, Simon J S; Bolt, Frances; Perdones-Montero, Alvaro; Rickards, Tony; Hardiman, Kate; Abdolrasouli, Alireza; Burke, Adam; Bodai, Zsolt; Karancsi, Tamas; Simon, Daniel; Schaffer, Richard; Rebec, Monica; Balog, Julia; Takáts, Zoltan

    2016-11-14

    Members of the genus Candida, such as C. albicans and C. parapsilosis, are important human pathogens. Other members of this genus, previously believed to carry minimal disease risk, are increasingly recognised as important human pathogens, particularly because of variations in susceptibilities to widely used anti-fungal agents. Thus, rapid and accurate identification of clinical Candida isolates is fundamental in ensuring timely and effective treatments are delivered. Rapid Evaporative Ionisation Mass Spectrometry (REIMS) has previously been shown to provide a high-throughput platform for the rapid and accurate identification of bacterial and fungal isolates. In comparison to commercially available matrix assisted laser desorption ionisation time of flight mass spectrometry (MALDI-ToF), REIMS based methods require no preparative steps nor time-consuming cell extractions. Here, we report on the ability of REIMS-based analysis to rapidly and accurately identify 153 clinical Candida isolates to species level. Both handheld bipolar REIMS and high-throughput REIMS platforms showed high levels of species classification accuracy, with 96% and 100% of isolates classified correctly to species level respectively. In addition, significantly different (FDR corrected P value < 0.05) lipids within the 600 to 1000 m/z mass range were identified, which could act as species-specific biomarkers in complex microbial communities.

  8. Rapid synaptic potentiation within the anterior cingulate cortex mediates trace fear learning

    Directory of Open Access Journals (Sweden)

    Descalzi Giannina

    2012-02-01

    Full Text Available Abstract Although the cortex has been extensively studied in long-term memory storage, less emphasis has been placed on immediate cortical contributions to fear memory formation. AMPA receptor plasticity is strongly implicated in learning and memory, and studies have identified calcium permeable AMPA receptors (CP-AMPARs as mediators of synaptic strengthening. Trace fear learning engages the anterior cingulate cortex (ACC, but whether plastic events occur within the ACC in response to trace fear learning, and whether GluN2B subunits are required remains unknown. Here we show that the ACC is necessary for trace fear learning, and shows a rapid 20% upregulation of membrane AMPA receptor GluA1 subunits that is evident immediately after conditioning. Inhibition of NMDA receptor GluN2B subunits during training prevented the upregulation, and disrupted trace fear memory retrieval 48 h later. Furthermore, intra-ACC injections of the CP-AMPAR channel antagonist, 1-naphthylacetyl spermine (NASPM immediately following trace fear conditioning blocked 24 h fear memory retrieval. Accordingly, whole cell patch clamp recordings from c-fos positive and c-fos negative neurons within the ACC in response to trace fear learning revealed an increased sensitivity to NASPM in recently activated neurons that was reversed by reconsolidation update extinction. Our results suggest that trace fear learning is mediated through rapid GluN2B dependent trafficking of CP-AMPARs, and present in vivo evidence that CP-AMPAR activity within the ACC immediately after conditioning is necessary for subsequent memory consolidation processes.

  9. Visual Perceptual Echo Reflects Learning of Regularities in Rapid Luminance Sequences.

    Science.gov (United States)

    Chang, Acer Y-C; Schwartzman, David J; VanRullen, Rufin; Kanai, Ryota; Seth, Anil K

    2017-08-30

    A novel neural signature of active visual processing has recently been described in the form of the "perceptual echo", in which the cross-correlation between a sequence of randomly fluctuating luminance values and occipital electrophysiological signals exhibits a long-lasting periodic (∼100 ms cycle) reverberation of the input stimulus (VanRullen and Macdonald, 2012). As yet, however, the mechanisms underlying the perceptual echo and its function remain unknown. Reasoning that natural visual signals often contain temporally predictable, though nonperiodic features, we hypothesized that the perceptual echo may reflect a periodic process associated with regularity learning. To test this hypothesis, we presented subjects with successive repetitions of a rapid nonperiodic luminance sequence, and examined the effects on the perceptual echo, finding that echo amplitude linearly increased with the number of presentations of a given luminance sequence. These data suggest that the perceptual echo reflects a neural signature of regularity learning.Furthermore, when a set of repeated sequences was followed by a sequence with inverted luminance polarities, the echo amplitude decreased to the same level evoked by a novel stimulus sequence. Crucially, when the original stimulus sequence was re-presented, the echo amplitude returned to a level consistent with the number of presentations of this sequence, indicating that the visual system retained sequence-specific information, for many seconds, even in the presence of intervening visual input. Altogether, our results reveal a previously undiscovered regularity learning mechanism within the human visual system, reflected by the perceptual echo.SIGNIFICANCE STATEMENT How the brain encodes and learns fast-changing but nonperiodic visual input remains unknown, even though such visual input characterizes natural scenes. We investigated whether the phenomenon of "perceptual echo" might index such learning. The perceptual echo is a

  10. Training of tonal similarity ratings in non-musicians: a "rapid learning" approach.

    Science.gov (United States)

    Oechslin, Mathias S; Läge, Damian; Vitouch, Oliver

    2012-01-01

    Although cognitive music psychology has a long tradition of expert-novice comparisons, experimental training studies are rare. Studies on the learning progress of trained novices in hearing harmonic relationships are still largely lacking. This paper presents a simple training concept using the example of tone/triad similarity ratings, demonstrating the gradual progress of non-musicians compared to musical experts: In a feedback-based "rapid learning" paradigm, participants had to decide for single tones and chords whether paired sounds matched each other well. Before and after the training sessions, they provided similarity judgments for a complete set of sound pairs. From these similarity matrices, individual relational sound maps, intended to display mental representations, were calculated by means of non-metric multidimensional scaling (NMDS), and were compared to an expert model through procrustean transformation. Approximately half of the novices showed substantial learning success, with some participants even reaching the level of professional musicians. Results speak for a fundamental ability to quickly train an understanding of harmony, show inter-individual differences in learning success, and demonstrate the suitability of the scaling method used for learning research in music and other domains. Results are discussed in the context of the "giftedness" debate.

  11. Rapid and accurate intraoperative pathological diagnosis by artificial intelligence with deep learning technology.

    Science.gov (United States)

    Zhang, Jing; Song, Yanlin; Xia, Fan; Zhu, Chenjing; Zhang, Yingying; Song, Wenpeng; Xu, Jianguo; Ma, Xuelei

    2017-09-01

    Frozen section is widely used for intraoperative pathological diagnosis (IOPD), which is essential for intraoperative decision making. However, frozen section suffers from some drawbacks, such as time consuming and high misdiagnosis rate. Recently, artificial intelligence (AI) with deep learning technology has shown bright future in medicine. We hypothesize that AI with deep learning technology could help IOPD, with a computer trained by a dataset of intraoperative lesion images. Evidences supporting our hypothesis included the successful use of AI with deep learning technology in diagnosing skin cancer, and the developed method of deep-learning algorithm. Large size of the training dataset is critical to increase the diagnostic accuracy. The performance of the trained machine could be tested by new images before clinical use. Real-time diagnosis, easy to use and potential high accuracy were the advantages of AI for IOPD. In sum, AI with deep learning technology is a promising method to help rapid and accurate IOPD. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Rapid Detection of OXA-48-Producing Enterobacteriaceae by Matrix-Assisted Laser Desorption Ionization−Time of Flight Mass Spectrometry

    Science.gov (United States)

    Oviaño, Marina; Barba, Maria José; Fernández, Begoña; Ortega, Adriana; Aracil, Belén; Oteo, Jesús; Campos, José

    2015-01-01

    A rapid and sensitive (100%) matrix-assisted laser desorption ionization−time of flight mass spectrometry (MALDI-TOF MS) assay was developed to detect OXA-48-type producers, using 161 previously characterized clinical isolates. Ertapenem was monitored to detect carbapenem resistance, and temocillin was included in the assay as a marker for OXA-48-producers. Structural analysis of temocillin is described. Data are obtained within 60 min. PMID:26677247

  13. Characterizing rapid, activity-linked conformational transitions in proteins via sub-second hydrogen deuterium exchange mass spectrometry.

    Science.gov (United States)

    Resetca, Diana; Wilson, Derek J

    2013-11-01

    This review outlines the application of time-resolved electrospray ionization mass spectrometry (TRESI-MS) and hydrogen-deuterium exchange (HDX) to study rapid, activity-linked conformational transitions in proteins. The method is implemented on a microfluidic chip which incorporates all sample-handling steps required for a 'bottom-up' HDX workflow: a capillary mixer for sub-second HDX labeling, a static mixer for HDX quenching, a microreactor for rapid protein digestion, and on-chip electrospray. By combining short HDX labeling pulses with rapid digestion, this approach provides a detailed characterization of the structural transitions that occur during protein folding, ligand binding, post-translational modification and catalytic turnover in enzymes. This broad spectrum of applications in areas largely inaccessible to conventional techniques means that microfluidics-enabled TRESI-MS/HDX is a unique and powerful approach for investigating the dynamic basis of protein function. © 2013 FEBS.

  14. Combination of SDS-PAGE and intact mass analysis for rapid determination of heterogeneities in monoclonal antibody therapeutics.

    Science.gov (United States)

    Yamada, Hideaki; Matsumura, Chiemi; Yamada, Keita; Teshima, Koichiro; Hiroshima, Takashi; Kinoshita, Mitsuhiro; Suzuki, Shigeo; Kakehi, Kazuaki

    2017-05-01

    mAbs are currently mainstream in biopharmaceuticals, and their market has been growing due to their high target specificity. Characterization of heterogeneities in mAbs is performed to secure their quality and safety by physicochemical analyses. However, they require time-consuming task, which often strain the resources of drug development in pharmaceuticals. Rapid and direct method to determine the heterogeneities should be a powerful tool for pharmaceutical analysis. Considering the advantages of electrophoresis and MS, this study addresses the combination of SDS-PAGE and intact mass analysis, which provides direct, rapid, and orthogonal determination of heterogeneities in mAb therapeutics. mAb therapeutics that migrated in SDS-PAGE were recovered from gel by treatment with SDC-containing buffer. Usage of SDC-containing buffer as extraction solvent and ethanol-based staining solution enhanced the recovery of intact IgG from SDS-PAGE gels. Recovery of mAbs reached more than 86% with 0.2% SD. The heterogeneities, especially N-glycan variants in the recovered mAb therapeutics, were clearly determined by intact mass analysis. We believe that the study is important in pharmaceuticals‧ perspective since orthogonal combination of gel electrophoresis and intact mass analysis should be pivotal role for rapid and precise characterization of mAbs. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Lessons Learned from Applying Design Thinking in a NASA Rapid Design Study in Aeronautics

    Science.gov (United States)

    McGowan, Anna-Maria; Bakula, Casey; Castner, Raymond

    2017-01-01

    In late 2015, NASA's Aeronautics Research Mission Directorate (ARMD) funded an experiment in rapid design and rapid teaming to explore new approaches to solving challenging design problems in aeronautics in an effort to cultivate and foster innovation. This report summarizes several lessons learned from the rapid design portion of the study. This effort entailed learning and applying design thinking, a human-centered design approach, to complete the conceptual design for an open-ended design challenge within six months. The design challenge focused on creating a capability to advance experimental testing of autonomous aeronautics systems, an area of great interest to NASA, the US government as a whole, and an entire ecosystem of users and developers around the globe. A team of nine civil servant researchers from three of NASA's aeronautics field centers with backgrounds in several disciplines was assembled and rapidly trained in design thinking under the guidance of the innovation and design firm IDEO. The design thinking process, while used extensively outside the aerospace industry, is less common and even counter to many practices within the aerospace industry. In this report, several contrasts between common aerospace research and development practices and design thinking are discussed, drawing upon the lessons learned from the NASA rapid design study. The lessons discussed included working towards a design solution without a set of detailed design requirements, which may not be practical or even feasible for management to ascertain for complex, challenging problems. This approach allowed for the possibility of redesigning the original problem statement to better meet the needs of the users. Another lesson learned was to approach problems holistically from the perspective of the needs of individuals that may be affected by advances in topic area instead of purely from a technological feasibility viewpoint. The interdisciplinary nature of the design team also

  16. Rapid changes in brain structure predict improvements induced by perceptual learning.

    Science.gov (United States)

    Ditye, Thomas; Kanai, Ryota; Bahrami, Bahador; Muggleton, Neil G; Rees, Geraint; Walsh, Vincent

    2013-11-01

    Practice-dependent changes in brain structure can occur in task relevant brain regions as a result of extensive training in complex motor tasks and long-term cognitive training but little is known about the impact of visual perceptual learning on brain structure. Here we studied the effect of five days of visual perceptual learning in a motion-color conjunction search task using anatomical MRI. We found rapid changes in gray matter volume in the right posterior superior temporal sulcus, an area sensitive to coherently moving stimuli, that predicted the degree to which an individual's performance improved with training. Furthermore, behavioral improvements were also predicted by volumetric changes in an extended white matter region underlying the visual cortex. These findings point towards quick and efficient plastic neural mechanisms that enable the visual brain to deal effectively with changing environmental demands. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. Adaptive Neuron Model: An architecture for the rapid learning of nonlinear topological transformations

    Science.gov (United States)

    Tawel, Raoul (Inventor)

    1994-01-01

    A method for the rapid learning of nonlinear mappings and topological transformations using a dynamically reconfigurable artificial neural network is presented. This fully-recurrent Adaptive Neuron Model (ANM) network was applied to the highly degenerate inverse kinematics problem in robotics, and its performance evaluation is bench-marked. Once trained, the resulting neuromorphic architecture was implemented in custom analog neural network hardware and the parameters capturing the functional transformation downloaded onto the system. This neuroprocessor, capable of 10(exp 9) ops/sec, was interfaced directly to a three degree of freedom Heathkit robotic manipulator. Calculation of the hardware feed-forward pass for this mapping was benchmarked at approximately 10 microsec.

  18. Cortical plasticity induced by rapid Hebbian learning of novel tonal word-forms : Evidence from mismatch negativity

    NARCIS (Netherlands)

    Yue, Jinxing; Bastiaanse, Roelien; Alter, Kai

    2014-01-01

    Although several experiments reported rapid cortical plasticity induced by passive exposure to novel segmental patterns, few studies have devoted attention to the neural dynamics during the rapid learning of novel tonal word-forms in tonal languages, such as Chinese. In the current study, native

  19. Rapid comparison of a candidate biosimilar to an innovator monoclonal antibody with advanced liquid chromatography and mass spectrometry technologies.

    Science.gov (United States)

    Xie, Hongwei; Chakraborty, Asish; Ahn, Joomi; Yu, Ying Qing; Dakshinamoorthy, Deepalakshmi P; Gilar, Martin; Chen, Weibin; Skilton, St John; Mazzeo, Jeffery R

    2010-01-01

    This study shows that state-of-the-art liquid chromatography (LC) and mass spectrometry (MS) can be used for rapid verification of identity and characterization of sequence variants and posttranslational modifications (PTMs) for antibody products. A candidate biosimilar IgG1 monoclonal antibody (mAb) was compared in detail to a commercially available innovator product. Intact protein mass, primary sequence, PTMs, and the micro-differences between the two mAbs were identified and quantified simultaneously. Although very similar in terms of sequences and modifications, a mass difference observed by LC-MS intact mass measurements indicated that they were not identical. Peptide mapping, performed with data independent acquisition LC-MS using an alternating low and elevated collision energy scan mode (LC-MS(E)), located the mass difference between the biosimilar and the innovator to a two amino acid residue variance in the heavy chain sequences. The peptide mapping technique was also used to comprehensively catalogue and compare the differences in PTMs of the biosimilar and innovator mAbs. Comprehensive glycosylation profiling confirmed that the proportion of individual glycans was different between the biosimilar and the innovator, although the number and identity of glycans were the same. These results demonstrate that the combination of accurate intact mass measurement, released glycan profiling, and LC-MS(E) peptide mapping provides a set of routine tools that can be used to comprehensively compare a candidate biosimilar and an innovator mAb.

  20. Training of tonal similarity ratings in non-musicians: a rapid learning approach

    Directory of Open Access Journals (Sweden)

    Mathias S Oechslin

    2012-05-01

    Full Text Available Although music psychology has a long tradition of expert-novice comparisons, experimental training studies are rare. Studies on the learning progress of trained novices in hearing harmonic relationships are still largely lacking. This paper presents a simple training concept using the example of tone/triad similarity ratings, demonstrating the gradual progress of non-musicians compared to musical experts: In a feedback-based rapid learning paradigm, participants had to decide for single tones and chords whether paired sounds matched each other well. Before and after the training sessions, they provided similarity judgments for a complete set of sound pairs. From these similarity matrices, individual relational sound maps, aiming to map the mental representations, were calculated by means of non-metric multidimensional scaling (NMDS, which were compared to an expert model through procrustean transformation. Approximately half of the novices showed substantial learning success, with some participants even reaching the level of professional musicians. Results speak for a fundamental ability to quickly train an understanding of harmony, show inter-individual differences in learning success, and demonstrate the suitability of the scaling method used for music psychological research. Results are discussed in the context of the giftedness debate.

  1. Rapid L2 Word Learning through High Constraint Sentence Context: An Event-Related Potential Study

    Directory of Open Access Journals (Sweden)

    Baoguo Chen

    2017-12-01

    Full Text Available Previous studies have found quantity of exposure, i.e., frequency of exposure (Horst et al., 1998; Webb, 2008; Pellicer-Sánchez and Schmitt, 2010, is important for second language (L2 contextual word learning. Besides this factor, context constraint and L2 proficiency level have also been found to affect contextual word learning (Pulido, 2003; Tekmen and Daloglu, 2006; Elgort et al., 2015; Ma et al., 2015. In the present study, we adopted the event-related potential (ERP technique and chose high constraint sentences as reading materials to further explore the effects of quantity of exposure and proficiency on L2 contextual word learning. Participants were Chinese learners of English with different English proficiency levels. For each novel word, there were four high constraint sentences with the critical word at the end of the sentence. Learners read sentences and made semantic relatedness judgment afterwards, with ERPs recorded. Results showed that in the high constraint condition where each pseudoword was embedded in four sentences with consistent meaning, N400 amplitude upon this pseudoword decreased significantly as learners read the first two sentences. High proficiency learners responded faster in the semantic relatedness judgment task. These results suggest that in high quality sentence contexts, L2 learners could rapidly acquire word meaning without multiple exposures, and L2 proficiency facilitated this learning process.

  2. Advanced Mass Spectrometric Methods for the Rapid and Quantitative Characterization of Proteomes

    Directory of Open Access Journals (Sweden)

    Richard D. Smith

    2006-04-01

    Full Text Available Progress is reviewed towards the development of a global strategy that aims to extend the sensitivity, dynamic range, comprehensiveness and throughput of proteomic measurements based upon the use of high performance separations and mass spectrometry. The approach uses high accuracy mass measurements from Fourier transform ion cyclotron resonance mass spectrometry (FTICR to validate peptide ‘accurate mass tags’ (AMTs produced by global protein enzymatic digestions for a specific organism, tissue or cell type from ‘potential mass tags’ tentatively identified using conventional tandem mass spectrometry (MS/MS. This provides the basis for subsequent measurements without the need for MS/ MS. High resolution capillary liquid chromatography separations combined with high sensitivity, and high resolution accurate FTICR measurements are shown to be capable of characterizing peptide mixtures of more than 105 components. The strategy has been initially demonstrated using the microorganisms Saccharomyces cerevisiae and Deinococcus radiodurans. Advantages of the approach include the high confidence of protein identification, its broad proteome coverage, high sensitivity, and the capability for stableisotope labeling methods for precise relative protein abundance measurements.

  3. Rapid tomato volatile profiling by using proton-transfer reaction mass spectrometry (PTS-MS)

    NARCIS (Netherlands)

    Farneti, B.; Cristescu, S.M.; Costa, G.; Harren, F.J.M.; Woltering, E.J.

    2012-01-01

    The availability of rapid and accurate methods to assess fruit flavor is of utmost importance to support quality control especially in the breeding phase. Breeders need more information and analytical tools to facilitate selection for complex multigenic traits such as flavor quality. In this study,

  4. Galaxy stellar mass functions from ZFOURGE/CANDELS: An excess of low-mass galaxies since z = 2 and the rapid buildup of quiescent galaxies

    Energy Technology Data Exchange (ETDEWEB)

    Tomczak, Adam R.; Tran, Kim-Vy H.; Papovich, Casey; Kawinwanichakij, Lalitwadee; Mehrtens, Nicola; Spitler, Lee R.; Tilvi, Vithal [George P. and Cynthia W. Mitchell Institute for Fundamental Physics and Astronomy, Department of Physics and Astronomy, Texas A and M University, College Station, TX 77843 (United States); Quadri, Ryan F.; Kelson, Daniel D.; McCarthy, Patrick J.; Monson, Andrew J.; Persson, S. Eric [Carnegie Observatories, Pasadena, CA 91101 (United States); Labbé, Ivo; Straatman, Caroline M. S. [Sterrewacht Leiden, Leiden University, NL-2300 RA Leiden (Netherlands); Glazebrook, Karl; Allen, Rebecca; Kacprzak, Glenn G. [Centre for Astrophysics and Supercomputing, Swinburne University, Hawthorn, VIC 3122 (Australia); Brammer, Gabriel B. [European Southern Observatory, Alonso de Córdova 3107, Casilla 19001, Vitacura, Santiago (Chile); Van Dokkum, Pieter, E-mail: tomczak@physics.tamu.edu [Department of Astronomy, Yale University, New Haven, CT 06520 (United States)

    2014-03-10

    Using observations from the FourStar Galaxy Evolution Survey (ZFOURGE), we obtain the deepest measurements to date of the galaxy stellar mass function (SMF) at 0.2 < z < 3. ZFOURGE provides well-constrained photometric redshifts made possible through deep medium-bandwidth imaging at 1-2 μm. We combine this with Hubble Space Telescope imaging from the Cosmic Assembly Near-IR Deep Extragalactic Legacy Survey, allowing for the efficient selection of both blue and red galaxies down to stellar masses of ∼10{sup 9.5} M {sub ☉} at z ∼ 2.5. The total surveyed area is 316 arcmin{sup 2} distributed over three independent fields. We supplement these data with the wider and shallower NEWFIRM Medium-Band Survey to provide stronger constraints at high masses. Several studies at z ≤ 1.5 have revealed a steepening of the slope at the low-mass end of the SMF, leading to an upturn at masses <10{sup 10} M {sub ☉} that is not well described by a standard single-Schechter function. We find evidence that this feature extends to at least z ∼ 2 and that it can be found in both the star-forming and quiescent populations individually. The characteristic mass (M*) and slope at the lowest masses (α) of a double-Schechter function fit to the SMF stay roughly constant at Log(M/M {sub ☉}) ∼ 10.65 and ∼ – 1.5, respectively. The SMF of star-forming galaxies has evolved primarily in normalization, while the change in shape is relatively minor. Our data allow us, for the first time, to observe a rapid buildup at the low-mass end of the quiescent SMF. Since z = 2.5, the total stellar mass density of quiescent galaxies (down to 10{sup 9} M {sub ☉}) has increased by a factor of ∼12, whereas the mass density of star-forming galaxies only increases by a factor of ∼2.2.

  5. Rapid confirmatory analysis of non-steroidal anti-inflammatory drugs in bovine milk by rapid resolution liquid chromatography tandem mass spectrometry.

    Science.gov (United States)

    Dowling, Geraldine; Gallo, Pasquale; Malone, Edward; Regan, Liam

    2009-11-13

    A rapid method has been developed to analyse carprofen (CPF), diclofenac (DCF), mefenamic acid (MFN), niflumic acid (NIFLU), naproxen (NAP), oxyphenylbutazone (OXYPHEN), phenylbutazone (PBZ) and suxibuzone (SUXI) residues in bovine milk. Milk samples are extracted with acetonitrile and sample extracts were purified on Evolute ABN solid phase extraction cartridges. Aliquots were analysed by rapid resolution liquid chromatography tandem mass spectrometry (RRLC-MS/MS) with a runtime of 6.5 min. The method was validated in bovine milk, according to the criteria defined in Commission Decision 2002/657/EC. CCalpha values of 0.46, 1.08, 0.92, 1.26, 1.29, 2.12, 0.55 and 2.86 ng mL(-1) were determined for CPF, DCF, MFN, NIFLU, NAP, OXYPHEN, PBZ and SUXI, respectively. CCbeta values of 0.79, 1.85, 1.56, 2.15, 2.19, 3.62, 0.94 and 4.87 ng mL(-1) were determined for CPF, DCF, MFN, NIFLU, NAP, OXYPHEN, PBZ and SUXI, respectively. The measurement uncertainty of the method was estimated at 9, 28, 28, 45, 46, 45, 10 and 39% for CPF, DCF, MFN, NIFLU, NAP, OXYPHEN, PBZ and SUXI. Fortifying bovine milk samples (n=18) in three separate assays, show the accuracy of the method to be between 82 and 108%. The precision of the method, expressed as RSD values for the within-lab reproducibility at the three levels of fortification (5, 7.5 and 10 ng mL(-1)) was less than 16%, respectively. The advantage of the method is that low ng mL(-1) levels can be detected and quantitatively confirmed rapidly in milk and that 3 batches of samples can be analysed within a single day using RRLC-MS/MS with a runtime of 6.5 min.

  6. Accurate Mass Fragment Library for Rapid Analysis of Pesticides on Produce Using Ambient Pressure Desorption Ionization with High-Resolution Mass Spectrometry

    Science.gov (United States)

    Kern, Sara E.; Lin, Lora A.; Fricke, Frederick L.

    2014-08-01

    U.S. food imports have been increasing steadily for decades, intensifying the need for a rapid and sensitive screening technique. A method has been developed that uses foam disks to sample the surface of incoming produce. This work provides complimentary information to the extensive amount of published pesticide fragmentation data collected using LCMS systems (Sack et al. Journal of Agricultural and Food Chemistry, 59, 6383-6411, 2011; Mol et al. Analytical and Bioanalytical Chemistry, 403, 2891-2908, 2012). The disks are directly analyzed using transmission-mode direct analysis in real time (DART) ambient pressure desorption ionization coupled to a high resolution accurate mass-mass spectrometer (HRAM-MS). In order to provide more certainty in the identification of the pesticides detected, a library of accurate mass fragments and isotopes of the protonated parent molecular ion (the [M+H]+) has been developed. The HRAM-MS is equipped with a quadrupole mass filter, providing the capability of "data-dependent" fragmentation, as opposed to "all -ion" fragmentation (where all of the ions enter a collision chamber and are fragmented at once). A temperature gradient for the DART helium stream and multiple collision energies were employed to detect and fragment 164 pesticides of varying chemical classes, sizes, and polarities. The accurate mass information of precursor ([M+H]+ ion) and fragment ions is essential in correctly identifying chemical contaminants on the surface of imported produce. Additionally, the inclusion of isotopes of the [M+H]+ in the database adds another metric to the confirmation process. The fragmentation data were collected using a Q-Exactive mass spectrometer and were added to a database used to process data collected with an Exactive mass spectrometer, an instrument that is more readily available for this screening application. The commodities investigated range from smooth-skinned produce such as apples to rougher surfaces like broccoli. The

  7. Rapid detection of cocaine, benzoylecgonine and methylecgonine in fingerprints using surface mass spectrometry.

    Science.gov (United States)

    Bailey, Melanie J; Bradshaw, Robert; Francese, Simona; Salter, Tara L; Costa, Catia; Ismail, Mahado; P Webb, Roger; Bosman, Ingrid; Wolff, Kim; de Puit, Marcel

    2015-09-21

    Latent fingerprints provide a potential route to the secure, high throughput and non-invasive detection of drugs of abuse. In this study we show for the first time that the excreted metabolites of drugs of abuse can be detected in fingerprints using ambient mass spectrometry. Fingerprints and oral fluid were taken from patients attending a drug and alcohol treatment service. Gas chromatography mass spectrometry (GC-MS) was used to test the oral fluid of patients for the presence of cocaine and benzoylecgonine. The corresponding fingerprints were analysed using Desorption Electrospray Ionization (DESI) which operates under ambient conditions and Ion Mobility Tandem Mass Spectrometry Matrix Assisted Laser Desorption Ionization (MALDI-IMS-MS/MS) and Secondary Ion Mass Spectrometry (SIMS). The detection of cocaine, benzoylecgonine (BZE) and methylecgonine (EME) in latent fingerprints using both DESI and MALDI showed good correlation with oral fluid testing. The sensitivity of SIMS was found to be insufficient for this application. These results provide exciting opportunities for the use of fingerprints as a new sampling medium for secure, non-invasive drug detection. The mass spectrometry techniques used here offer a high level of selectivity and consume only a small area of a single fingerprint, allowing repeat and high throughput analyses of a single sample.

  8. Rapid sample classification using an open port sampling interface coupled with liquid introduction atmospheric pressure ionization mass spectrometry.

    Science.gov (United States)

    Van Berkel, Gary J; Kertesz, Vilmos

    2017-02-15

    An "Open Access"-like mass spectrometric platform to fully utilize the simplicity of the manual open port sampling interface for rapid characterization of unprocessed samples by liquid introduction atmospheric pressure ionization mass spectrometry has been lacking. The in-house developed integrated software with a simple, small and relatively low-cost mass spectrometry system introduced here fills this void. Software was developed to operate the mass spectrometer, to collect and process mass spectrometric data files, to build a database and to classify samples using such a database. These tasks were accomplished via the vendor-provided software libraries. Sample classification based on spectral comparison utilized the spectral contrast angle method. Using the developed software platform near real-time sample classification is exemplified using a series of commercially available blue ink rollerball pens and vegetable oils. In the case of the inks, full scan positive and negative ion ESI mass spectra were both used for database generation and sample classification. For the vegetable oils, full scan positive ion mode APCI mass spectra were recorded. The overall accuracy of the employed spectral contrast angle statistical model was 95.3% and 98% in case of the inks and oils, respectively, using leave-one-out cross-validation. This work illustrates that an open port sampling interface/mass spectrometer combination, with appropriate instrument control and data processing software, is a viable direct liquid extraction sampling and analysis system suitable for the non-expert user and near real-time sample classification via database matching. Published in 2016. This article is a U.S. Government work and is in the public domain in the USA. Published in 2016. This article is a U.S. Government work and is in the public domain in the USA.

  9. Rapid development of adaptive, climate-driven clinal variation in seed mass in the invasive annual Forb Echium plantagineum L.

    Directory of Open Access Journals (Sweden)

    Tara K Konarzewski

    Full Text Available We examined adaptive clinal variation in seed mass among populations of an invasive annual species, Echium plantagineum, in response to climatic selection. We collected seeds from 34 field populations from a 1,000 km long temperature and rainfall gradient across the species' introduced range in south-eastern Australia. Seeds were germinated, grown to reproductive age under common glasshouse conditions, and progeny seeds were harvested and weighed. Analyses showed that seed mass was significantly related to climatic factors, with populations sourced from hotter, more arid sites producing heavier seeds than populations from cooler and wetter sites. Seed mass was not related to edaphic factors. We also found that seed mass was significantly related to both longitude and latitude with each degree of longitude west and latitude north increasing seed mass by around 2.5% and 4% on average. There was little evidence that within-population or between-population variation in seed mass varied in a systematic manner across the study region. Our findings provide compelling evidence for development of a strong cline in seed mass across the geographic range of a widespread and highly successful invasive annual forb. Since large seed mass is known to provide reproductive assurance for plants in arid environments, our results support the hypothesis that the fitness and range potential of invasive species can increase as a result of genetic divergence of populations along broad climatic gradients. In E. plantagineum population-level differentiation has occurred in 150 years or less, indicating that the adaptation process can be rapid.

  10. Mass Balance Evolution of Black Rapids Glacier, Alaska, 1980–2100, and Its Implications for Surge Recurrence

    Directory of Open Access Journals (Sweden)

    Christian Kienholz

    2017-07-01

    Full Text Available Surge-type Black Rapids Glacier, Alaska, has undergone strong retreat since it last surged in 1936–1937. To assess its evolution during the late Twentieth and Twenty-first centuries and determine potential implications for surge likelihood, we run a simplified glacier model over the periods 1980–2015 (hindcasting and 2015–2100 (forecasting. The model is forced by daily temperature and precipitation fields, with downscaled reanalysis data used for the hindcasting. A constant climate scenario and an RCP 8.5 scenario based on the GFDL-CM3 climate model are employed for the forecasting. Debris evolution is accounted for by a debris layer time series derived from satellite imagery (hindcasting and a parametrized debris evolution model (forecasting. A retreat model accounts for the evolution of the glacier geometry. Model calibration, validation and parametrization rely on an extensive set of in situ and remotely sensed observations. To explore uncertainties in our projections, we run the glacier model in a Monte Carlo fashion, varying key model parameters and input data within plausible ranges. Our results for the hindcasting period indicate a negative mass balance trend, caused by atmospheric warming in the summer, precipitation decrease in the winter and surface elevation lowering (climate-elevation feedback, which exceed the moderating effects from increasing debris cover and glacier retreat. Without the 2002 rockslide deposits on Black Rapids' lower reaches, the mass balances would be more negative, by ~20% between the 2003 and 2015 mass-balance years. Despite its retreat, Black Rapids Glacier is substantially out of balance with the current climate. By 2100, ~8% of Black Rapids' 1980 area are projected to vanish under the constant climate scenario and ~73% under the RCP 8.5 scenario. For both scenarios, the remaining glacier portions are out of balance, suggesting continued retreat after 2100. Due to mass starvation, a surge in the Twenty

  11. Mass balance evolution of Black Rapids Glacier, Alaska, 1980-2100, and its implications for surge recurrence

    Science.gov (United States)

    Kienholz, Christian; Hock, Regine; Truffer, Martin; Bieniek, Peter; Lader, Richard

    2017-07-01

    Surge-type Black Rapids Glacier, Alaska, has undergone strong retreat since it last surged in 1936-37. To assess its evolution during the late 20th and 21st centuries and determine potential implications for surge likelihood, we run a simplified glacier model over the periods 1980-2015 (hindcasting) and 2015-2100 (forecasting). The model is forced by daily temperature and precipitation fields, with downscaled reanalysis data used for the hindcasting. A constant climate scenario and an RCP 8.5 scenario based on the GFDL-CM3 climate model are employed for the forecasting. Debris evolution is accounted for by a debris layer time series derived from satellite imagery (hindcasting) and a parametrized debris evolution model (forecasting). A retreat model accounts for the evolution of the glacier geometry. Model calibration, validation and parametrization rely on an extensive set of in situ and remotely sensed observations. To explore uncertainties in our projections, we run the glacier model in a Monte Carlo fashion, varying key model parameters and input data within plausible ranges. Our results for the hindcasting period indicate a negative mass balance trend, caused by atmospheric warming in the summer, precipitation decrease in the winter and surface elevation lowering (climate-elevation feedback), which exceed the moderating effects from increasing debris cover and glacier retreat. Without the 2002 rockslide deposits on Black Rapids' lower reaches, the mass balances would be more negative, by 20% between the 2003 and 2015 mass-balance years. Despite its retreat, Black Rapids Glacier is substantially out of balance with the current climate. By 2100, 8% of Black Rapids' 1980 area are projected to vanish under the constant climate scenario and 73% under the RCP 8.5 scenario. For both scenarios, the remaining glacier portions are out of balance, suggesting continued retreat after 2100. Due to mass starvation, a surge in the 21st century is unlikely. The projected

  12. Mass fingerprint analysis of spider mites (Acari) by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry for rapid discrimination.

    Science.gov (United States)

    Kajiwara, Hideyuki; Hinomoto, Norihide; Gotoh, Tetsuo

    2016-04-30

    Discrimination of spider mite species is still performed using morphological information, although DNA and other biological approaches have been attempted for identification purposes. These techniques need much time, are expensive, and require specialist staff. As an alternative, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) analysis is applied for rapid discrimination of spider mite species. Spider mites were analyzed using MALDI-TOFMS after extraction with 70% formic acid and acetonitrile. A single spider mite was also analyzed directly on double-sided carbon tape. A dendrogram was compiled from the MS data. Evolutionarily close and morphologically similar spider mites, the Kanzawa (Tetranychus kanzawai) and the two-spotted (T. urticae) spider mites, as well as three other related species of spider mites, could be discriminated by mass fingerprints. Although female adults were mainly used in this report, male adults and nymphs showed almost the same mass fingerprints and were not considered to affect discrimination capability. A single spider mite on double-sided carbon tape was analyzed directly by MALDI-TOFMS. Spider mites could be analyzed directly by MALDI-TOFMS, with evolutionarily and morphologically closely related spider mites showing different mass fingerprints, allowing for their identification. Copyright © 2016 John Wiley & Sons, Ltd.

  13. Microstructural evolution in a rapidly solidified Al-4mass%Fe droplet

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seong-Gyoon (Department of Materials Science and Engineering, Kunsan National University, Kunsan 573-360 (Korea, Republic of)); Shin, Seong-Ho (Central Laboratory, Sammi Special Steel Company, Changwon 641-050 (Korea, Republic of)); Suzuki, Toshio (Engineering Research Institute, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113 (Japan)); Umeda, Takateru (Department of Metallurgy, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113 (Japan))

    1994-05-15

    A two-dimensional non-newtonian numerical analysis on the solidification of Al-4mass%Fe droplet was represented which includes the transition between the partitionless and partitioned solidification modes. It was shown that, instead of the banded-structure formation, a strong instability on the macroscopic solid-liquid interface occurs in the transition range. The patterns predicted as functions of the initial undercooling and the droplet size were compared with the microstructures of the gas-atomized Al-4mass%Fe powders. ((orig.))

  14. Process Modelling of Rapid Manufacturing Based Mass Customisation System for Fabrication of Custom Foot Orthoses: Review Paper

    Directory of Open Access Journals (Sweden)

    Saleh Jumani

    2013-04-01

    Full Text Available The need for custom-made devices, rehabilitation aids and treatments is explicit in the medical sector. Applications of rapid manufacturing techniques based on additive fabrication processes combined with medical digitising technologies can generate high quality solutions in situations where the need for custom-made devices and rehabilitation aids and low-lead times are very important factors. Foot orthoses are medical devices applied in the treatment of biomechanical foot disorders, foot injuries and foot diseases including rheumatoid arthritis and diabetes. The significant challenge in the treatment of foot related diseases is progressing pathological deterioration in the affected sites of the foot which requires quick provision of the orthoses. A process model is developed using the IDEF0 modelling technique in which a rapid manufacturing approach is integrated in the design and fabrication process of custom foot orthoses. The process model will be used in the development of rapid manufacturing based design and fabrication system for mass customisation of foot orthoses. The developed system is aimed at mass scale production of custom foot orthoses with the advantages of reduced cost, reduced lead-time and improved product in terms of increased fit, consistency and accuracy in the final product.

  15. Modular Rapid E-Learning Framework (MORELFT in Desktop Virtualization Environment: An Effective Hybrid Implementation in Nurse Education

    Directory of Open Access Journals (Sweden)

    Alaattin PARLAKKILIC

    2015-01-01

    Full Text Available Generally it is not easy for an instructor to prepare and deliver electronic courses via e-learning. Therefore it is necessary to work and develop an easy system. In this context module technology was used to for provide modularity in conducting educational development of e-learning course. Then, rapid e-learning was used for more quick and easy course development. In order to implement modular rapid e-learning, a desktop virtual environment was set up. Modular rapid e-learning was used by teachers and students in a one semester course and student success and reactions were evaluated. And also the overall hybrid system cost was calculated and reported. In implementation we combined modular course design with rapid e-learning and desktop virtualization in education of 3rd year nursing students for a one semester course. The effectiveness of this hybrid method was evaluated with respect to students’ success, students’ opinions and over all cost effectiveness. It was seen that the hybrid method was educationally more effective than traditional method comparing with previous year students' success and fit with students’ requirements. The cost reduction was %41 comparing with traditional desktop and e-learning system.

  16. Improved Neural Signal Classification in a Rapid Serial Visual Presentation Task Using Active Learning.

    Science.gov (United States)

    Marathe, Amar R; Lawhern, Vernon J; Wu, Dongrui; Slayback, David; Lance, Brent J

    2016-03-01

    The application space for brain-computer interface (BCI) technologies is rapidly expanding with improvements in technology. However, most real-time BCIs require extensive individualized calibration prior to use, and systems often have to be recalibrated to account for changes in the neural signals due to a variety of factors including changes in human state, the surrounding environment, and task conditions. Novel approaches to reduce calibration time or effort will dramatically improve the usability of BCI systems. Active Learning (AL) is an iterative semi-supervised learning technique for learning in situations in which data may be abundant, but labels for the data are difficult or expensive to obtain. In this paper, we apply AL to a simulated BCI system for target identification using data from a rapid serial visual presentation (RSVP) paradigm to minimize the amount of training samples needed to initially calibrate a neural classifier. Our results show AL can produce similar overall classification accuracy with significantly less labeled data (in some cases less than 20%) when compared to alternative calibration approaches. In fact, AL classification performance matches performance of 10-fold cross-validation (CV) in over 70% of subjects when training with less than 50% of the data. To our knowledge, this is the first work to demonstrate the use of AL for offline electroencephalography (EEG) calibration in a simulated BCI paradigm. While AL itself is not often amenable for use in real-time systems, this work opens the door to alternative AL-like systems that are more amenable for BCI applications and thus enables future efforts for developing highly adaptive BCI systems.

  17. Contributions of the hippocampus and entorhinal cortex to rapid visuomotor learning in rhesus monkeys.

    Science.gov (United States)

    Yang, Tianming; Bavley, Rachel L; Fomalont, Kevin; Blomstrom, Kevin J; Mitz, Andrew R; Turchi, Janita; Rudebeck, Peter H; Murray, Elisabeth A

    2014-09-01

    The hippocampus and adjacent structures in the medial temporal lobe are essential for establishing new associative memories. Despite this knowledge, it is not known whether the hippocampus proper is essential for establishing such memories, nor is it known whether adjacent regions like the entorhinal cortex might contribute. To test the contributions of these regions to the formation of new associative memories, we trained rhesus monkeys to rapidly acquire arbitrary visuomotor associations, i.e., associations between visual stimuli and spatially directed actions. We then assessed the effects of reversible inactivations of either the hippocampus (Experiment 1) or entorhinal cortex (Experiment 2) on the within-session rate of learning. For comparison, we also evaluated the effects of the inactivations on performance of problems of the same type that had been well learned prior to any inactivations. We found that inactivation of the entorhinal cortex but not hippocampus produced impairments in acquiring novel arbitrary associations. The impairment did not extend to the familiar, previously established associations. These data indicate that the entorhinal cortex is causally involved in establishing new associations, as opposed to retrieving previously learned associations. Published 2014. This article is a U.S. Government work and is in the public domain in the USA. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

  18. Rapid mass spectrometric analysis of 15N-Leu incorporation fidelity during preparation of specifically labeled NMR samples

    DEFF Research Database (Denmark)

    Truhlar, Stephanie M E; Cervantes, Carla F; Torpey, Justin W

    2008-01-01

    . MALDI TOF-TOF MS/MS data provide additional information that shows where the "extra" (15)N labels are incorporated, which can be useful in confirming ambiguous assignments. The described procedure provides a rapid technique to monitor the fidelity of selective labeling that does not require a lot......Advances in NMR spectroscopy have enabled the study of larger proteins that typically have significant overlap in their spectra. Specific (15)N-amino acid incorporation is a powerful tool for reducing spectral overlap and attaining reliable sequential assignments. However, scrambling of the label...... during protein expression is a common problem. We describe a rapid method to evaluate the fidelity of specific (15)N-amino acid incorporation. The selectively labeled protein is proteolyzed, and the resulting peptides are analyzed using MALDI mass spectrometry. The (15)N incorporation is determined...

  19. A deep learning approach for the analysis of masses in mammograms with minimal user intervention.

    Science.gov (United States)

    Dhungel, Neeraj; Carneiro, Gustavo; Bradley, Andrew P

    2017-04-01

    We present an integrated methodology for detecting, segmenting and classifying breast masses from mammograms with minimal user intervention. This is a long standing problem due to low signal-to-noise ratio in the visualisation of breast masses, combined with their large variability in terms of shape, size, appearance and location. We break the problem down into three stages: mass detection, mass segmentation, and mass classification. For the detection, we propose a cascade of deep learning methods to select hypotheses that are refined based on Bayesian optimisation. For the segmentation, we propose the use of deep structured output learning that is subsequently refined by a level set method. Finally, for the classification, we propose the use of a deep learning classifier, which is pre-trained with a regression to hand-crafted feature values and fine-tuned based on the annotations of the breast mass classification dataset. We test our proposed system on the publicly available INbreast dataset and compare the results with the current state-of-the-art methodologies. This evaluation shows that our system detects 90% of masses at 1 false positive per image, has a segmentation accuracy of around 0.85 (Dice index) on the correctly detected masses, and overall classifies masses as malignant or benign with sensitivity (Se) of 0.98 and specificity (Sp) of 0.7. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. A rapid and specific derivatization procedure to identify acyl-glucuronides by mass spectrometry.

    Science.gov (United States)

    Vaz, Alfin D N; Wang, Wei Wei; Bessire, Andrew J; Sharma, Raman; Hagen, Anne E

    2010-07-30

    A simple procedure is described to identify acyl-glucuronides by coupled liquid chromatography/mass spectrometry after derivatization to a hydroxamic acid with hydroxylamine. The reaction specificity obviates the need for isolation of the acyl-glucuronide from an extract. Glucuronides derived from carbamic acids, and alkyl- and aromatic amines, are inert to the derivatization reaction conditions, making the hydroxamic acid derivative a fingerprint for acyl-glucuronides. Copyright 2010 John Wiley & Sons, Ltd.

  1. Barrier Free Conditions of Mass Rapid Transit Stations in Hong Kong

    OpenAIRE

    OSAKAYA, Yoshiyuki; Aoyama, Takeshi; RATANAMART, Suphawadee

    2010-01-01

    In Hong Kong, it is estimated that aging will be rapidly going on after 2010. Increase of the elderly means increase of the disabled. In Hong Kong, there are 3 KCR lines(East Line, West Line and Ma On Shan Line) and 7 MTR lines(Kwun Tong Line, Tsuen Wan Line, Island Line, Tsueng Wan O Line,Tung Chung Line, Airport Line and Disneyland Line) in 2006. This study firstly made the actual conditions of barrier free at all 81 stations clear. It secondly made problems clear. It thirdly showed proposa...

  2. Human serum processing and analysis methods for rapid and reproducible N-glycan mass profiling.

    Science.gov (United States)

    Kronewitter, Scott R; de Leoz, Maria Lorna A; Peacock, Kyle S; McBride, Kelly R; An, Hyun Joo; Miyamoto, Suzanne; Leiserowitz, Gary S; Lebrilla, Carlito B

    2010-10-01

    Glycans constitute a new class of compounds for biomarker discovery. Glycosylation is a common post-translational modification and is often associated with transformation to malignancy. To analyze glycans, they are released from proteins, enriched, and measured with mass spectrometry. For biomarker discovery, repeatability at every step of the process is important. Locating and minimizing the process variability is key to establishing a robust platform stable enough for biomarker discovery. Understanding the variability of the measurement devices helps understand the variability associated with the chemical processing. This report explores the potential use of methods expediting the enzymatic release of glycans such as a microwave reactor and automation of the solid-phase extraction with a robotic liquid handler. The study employs matrix-assisted laser desorption/ionization-Fourier transform ion cyclotron resonance mass spectrometry but would be suitable with any mass spectrometry method. Methods for system-wide data analysis are examined because proper metrics for evaluating the performance of glycan sample preparation procedures are not well established.

  3. Rapid analysis of urinary opiates using fast gas chromatography–mass spectrometry and hydrogen as a carrier gas

    Directory of Open Access Journals (Sweden)

    Sumandeep Rana

    2014-09-01

    Gas chromatographic–mass spectrometric analysis was performed in electron ionization mode by selective ion monitoring, using hydrogen as a carrier gas, a short narrow bore GC capillary column, and fast temperature program, allowing for a rapid analytical cycle to maximize the instrument time for high throughput laboratories. While maintaining specificity for these drugs, concentrations in human urine ranging from 50 to 5,000 ng/mL can be measured with intraday and interday imprecision, expressed as variation coefficients, of less than 2.3% for all analytes within a run time of less than 3.5 minutes.

  4. Rapid and Accurate Identification of Animal Species in Natural Leather Goods by Liquid Chromatography/Mass Spectrometry.

    Science.gov (United States)

    Izuchi, Yukari; Takashima, Tsuneo; Hatano, Naoya

    2016-01-01

    The demand for leather goods has grown globally in recent years. Industry revenue is forecast to reach $91.2 billion by 2018. There is an ongoing labelling problem in the leather items market, in that it is currently impossible to identify the species that a given piece of leather is derived from. To address this issue, we developed a rapid and simple method for the specific identification of leather derived from cattle, horses, pigs, sheep, goats, and deer by analysing peptides produced by the trypsin-digestion of proteins contained in leather goods using liquid chromatography/mass spectrometry. We determined species-specific amino acid sequences by liquid chromatography/tandem mass spectrometry analysis using the Mascot software program and demonstrated that collagen α-1(I), collagen α-2(I), and collagen α-1(III) from the dermal layer of the skin are particularly useful in species identification.

  5. Learning Curves of Virtual Mastoidectomy in Distributed and Massed Practice

    DEFF Research Database (Denmark)

    Andersen, Steven Arild Wuyts; Konge, Lars; Cayé-Thomasen, Per

    2015-01-01

    IMPORTANCE: Repeated and deliberate practice is crucial in surgical skills training, and virtual reality (VR) simulation can provide self-directed training of basic surgical skills to meet the individual needs of the trainee. Assessment of the learning curves of surgical procedures is pivotal in ...

  6. From Reciprocity to Interdependence: Mass Incarceration and Service-Learning

    Science.gov (United States)

    Ryder, Phyllis Mentzell

    2016-01-01

    This essay considers the difficulty of seeing systems of oppression--a challenging first step of writing for social change. I argue that service-learning faculty and public writing scholars have relied on outdated ways of thinking about racism and oppression, treating social issues as isolated instances of discrimination. Instead, by drawing from…

  7. Precision mass measurements for studies of nucleosynthesis via the rapid neutron-capture process. Penning-trap mass measurements of neutron-rich cadmium and caesium isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Atanasov, Dinko

    2016-07-06

    Although the theory for the rapid neutron-capture process (r-process) was developed more than 55 years ago, the astrophysical site is still under a debate. Theoretical studies predict that the r-process path proceeds through very neutron-rich nuclei with very asymmetric proton-to-neutron ratios. Knowledge about the properties of neutron-rich isotopes found in similar regions of the nuclear chart and furthermore suitable for r-process studies is still little or even not existing. The basic nuclear properties such as binding energies, half-lives, neutron-induced or neutron-capture reaction cross-sections, play an important role in theoretical simulations and can vary or even drastically alternate results of these studies. Therefore, a considerable effort was put forward to access neutron-rich isotopes at radioactive ion-beam facilities like ISOLDE at CERN. The goal of this PhD thesis is to describe the experimental work done for the precision mass measurements of neutron-rich cadmium ({sup 129-131}Cd) and caesium ({sup 132,146-148}Cs) isotopes. Measurements were done at the on-line radioactive ion-beam facility ISOLDE by using the four-trap mass spectrometer ISOLTRAP. The cadmium isotopes are key nuclides for the synthesis of stable isotopes around the mass peak A = 130 in the Solar System abundance.

  8. Evaluation of methods of rapid mass killing of segregated early weaned piglets.

    Science.gov (United States)

    Whiting, Terry L; Steele, Gregory G; Wamnes, Steinar; Green, Chris

    2011-07-01

    The operational logistics of mass killing of healthy, surplus piglets by manual blunt force trauma, controlled blunt force trauma, intraperitoneal injection of barbiturate, and free bullet were recorded. Objective performance variables evaluated were, speed of application, human resource and input cost, animal restraint required, and failure rate. Subjective evaluation of esthetics and difficulty of application indicated manual blunt force trauma is an unacceptable technique. Under field conditions, physical methods of killing were superior to intraperitoneal injection of concentrated pentobarbital. Considering animal welfare metrics in isolation, controlled blunt force trauma was superior to all other techniques attempted.

  9. Weight, Mass, and Gravity: Threshold Concepts in Learning Science

    Science.gov (United States)

    Bar, Varda; Brosh, Yaffa; Sneider, Cary

    2016-01-01

    Threshold concepts are essential ideas about the natural world that present either a barrier or a gateway to a deep understanding of science. Weight, mass, and gravity are threshold concepts that underpin students' abilities to understand important ideas in all fields of science, embodied in the performance expectations in the Next Generation…

  10. Rapid detection of economic adulterants in fresh milk by liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Abernethy, Grant; Higgs, Kerianne

    2013-05-03

    A method to aid in the detection of the economically driven adulteration of fresh milk with a range of small, nitrogen containing compounds, including melamine, ammeline, ammelide, cyanuric acid, allantoin, thiourea, urea, biuret, triuret, semicarbazide, aminotriazine, 3- and 4-aminotriazole, cyanamide, dicyandiamide, guanidine, choline, hydroxyproline, nitrate, and a range of amino acids, has been developed. (15)N2-Urea is used as an internal standard. The adulteration of milk with exogenous urea has previously been difficult to detect because of the variation in the naturally occurring levels of urea in milk. However, by monitoring the contaminants biuret and triuret, which comprise up to 1% of synthetic urea, the adulteration of milk with urea-based fertilizer can be detected. We estimate that to be economically viable, adulteration of the order of 90-4000ppm of the above adulterants would need to be added to fresh milk. For most of the compounds, an arbitrary detection threshold of 2ppm is therefore more than sufficient. For biuret, a lower detection threshold, better than 0.5ppm, is desirable and the sensitivity for biuret and triuret can be improved by the post-column addition of lithium to create lithium adducts under electrospray ionisation. Sample handling involves a two-step solvent precipitation method that is deployed in a 96-well plate format, and the hydrophilic interaction liquid chromatography uses a rapid gradient (1.2min). Three separate injections, to detect the positively charged compounds, the negatively charged compounds and amino acids and finally the lithium adducts, are used. This rapid and qualitative survey method may be deployed as a second tier screening method to quickly reduce sample numbers indicated as irregular by an FTIR based screening system, and to direct analysis to appropriate quantification methods. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. Rapid Preconcentration for Liquid Chromatography-Mass Spectrometry Assay of Trace Level Neuropeptides

    Science.gov (United States)

    Zhou, Ying; Mabrouk, Omar S.; Kennedy, Robert T.

    2013-11-01

    Measurement of neuropeptides in the brain through in vivo microdialysis sampling provides direct correlation between neuropeptide concentration and brain function. Capillary liquid chromatography-multistage mass spectrometry (CLC-MSn) has proven to be effective at measuring endogenous neuropeptides in microdialysis samples. In the method, microliter samples are concentrated onto nanoliter volume packed beds before ionization and mass spectrometry analysis. The long times required for extensive preconcentration present a barrier to routine use because of the many samples that must be analyzed and instability of neuropeptides. In this study, we evaluated the capacity of 75 μm inner diameter (i.d.) capillary column packed with 10 μm reversed phase particles for increasing the throughput in CLC-MSn based neuropeptide measurement. Coupling a high injection flow rate for fast sample loading/desalting with a low elution flow rate to maintain detection sensitivity, this column has reduced analysis time from ˜30 min to 3.8 min for 5 μL sample, with 3 pM limit of detection (LOD) for enkephalins and 10 pM LOD for dynorphin A1-8 in 5 μL sample. The use of isotope-labeled internal standard lowered peptide signal variation to less than 5 %. This method was validated for in vivo detection of Leu and Met enkephalin with microdialysate collected from rat globus pallidus. The improvement in speed and stability makes CLC-MSn measurement of neuropeptides in vivo more practical.

  12. Stress-enhanced fear learning in rats is resistant to the effects of immediate massed extinction.

    Science.gov (United States)

    Long, Virginia A; Fanselow, Michael S

    2012-11-01

    Enhanced fear learning occurs subsequent to traumatic or stressful events and is a persistent challenge to the treatment of post-traumatic stress disorder (PTSD). Facilitation of learning produced by prior stress can elicit an exaggerated fear response to a minimally aversive event or stimulus. Stress-enhanced fear learning (SEFL) is a rat model of PTSD; rats previously exposed to the SEFL 15 electrical shocks procedure exhibit several behavioral responses similar to those seen in patients with PTSD. However, past reports found that SEFL is not mitigated by extinction (a model of exposure therapy) when the spaced extinction began 24 h after stress. Recent studies found that extinction from 10 min to 1 h subsequent to fear conditioning "erased" learning, whereas later extinction, occurring from 24 to 72 h after conditioning did not. Other studies indicate that massed extinction is more effective than spaced procedures. Therefore, we examined the time-dependent nature of extinction on the stress-induced enhancement of fear learning using a massed trial's procedure. Experimental rats received 15 foot shocks and were given either no extinction or massed extinction 10 min or 72 h later. Our present data indicate that SEFL, following traumatic stress, is resistant to immediate massed extinction. Experimental rats showed exaggerated new fear learning regardless of when extinction training occurred. Thus, post-traumatic reactivity such as SEFL does not seem responsive to extinction treatments.

  13. Stress-enhanced fear learning in rats is resistant to the effects of immediate massed extinction

    Science.gov (United States)

    Long, Virginia A.; Fanselow, Michael S.

    2014-01-01

    Enhanced fear learning occurs subsequent to traumatic or stressful events and is a persistent challenge to the treatment of post-traumatic stress disorder (PTSD). Facilitation of learning produced by prior stress can elicit an exaggerated fear response to a minimally aversive event or stimulus. Stress-enhanced fear learning (SEFL) is a rat model of PTSD; rats previously exposed to the SEFL 15 electrical shocks procedure exhibit several behavioral responses similar to those seen in patients with PTSD. However, past reports found that SEFL is not mitigated by extinction (a model of exposure therapy) when the spaced extinction began 24 h after stress. Recent studies found that extinction from 10 min to 1 h subsequent to fear conditioning “erased” learning, whereas later extinction, occurring from 24 to 72 h after conditioning did not. Other studies indicate that massed extinction is more effective than spaced procedures. Therefore, we examined the time-dependent nature of extinction on the stress-induced enhancement of fear learning using a massed trial’s procedure. Experimental rats received 15 foot shocks and were given either no extinction or massed extinction 10 min or 72 h later. Our present data indicate that SEFL, following traumatic stress, is resistant to immediate massed extinction. Experimental rats showed exaggerated new fear learning regardless of when extinction training occurred. Thus, post-traumatic reactivity such as SEFL does not seem responsive to extinction treatments. PMID:22176467

  14. Direct analysis in real time mass spectrometry for the rapid identification of four highly hazardous pesticides in agrochemicals.

    Science.gov (United States)

    Wang, Lei; Zhao, Pengyue; Zhang, Fengzu; Li, Yanjie; Pan, Canping

    2012-08-30

    Direct analysis in real time (DART) is a new ion source technique, which is conducted in the open air under ambient conditions, applied to the rapid and direct analysis of any material (gases, liquids, and solids) with minimal or no sample preparation. In order to take advantage of the capacity of DART mass spectrometry for the real-time analysis of hazardous ingredients in commercial agrochemicals, a pilot study of rapid qualitative determination of hazardous pesticides was performed. Highly hazardous pesticides were identified by DART ionization coupled to a single-quadrupole mass spectrometer (DART-MS). Acetonitrile was chosen for dissolving samples prior to the analysis. Samples were analyzed by this technique in as little as 5 s. Phorate, carbofuran, ethoprophos and fipronil were be detected directly from commercial agrochemicals. The ionization-related parameters (DART temperature, grid voltage and MS fragment) of these compounds were optimized to obtain highly response. Isotope patterns were taken into consideration for qualitative identification. Relative standard deviations (RSDs, n = 5) of 2.3-15.0% were obtained by measuring the relative abundance of selected isotopes. This study showed that DART-MS technology was able to qualitatively determine the existence of highly hazardous pesticides in commercial pesticide formulations. It is suggested that this technology should be applied for routine monitoring in the market. Copyright © 2012 John Wiley & Sons, Ltd.

  15. Rapid fingerprinting and classification of extra virgin olive oil by microjet sampling and extractive electrospray ionization mass spectrometry.

    Science.gov (United States)

    Law, Wai Siang; Chen, Huan Wen; Balabin, Roman; Berchtold, Christian; Meier, Lukas; Zenobi, Renato

    2010-04-01

    Microjet sampling in combination with extractive electrospray ionization (EESI) mass spectrometry (MS) was applied to the rapid characterization and classification of extra virgin olive oil (EVOO) without any sample pretreatment. When modifying the composition of the primary ESI spray solvent, mass spectra of an identical EVOO sample showed differences. This demonstrates the capability of this technique to extract molecules with varying polarities, hence generating rich molecular information of the EVOO. Moreover, with the aid of microjet sampling, compounds of different volatilities (e.g.E-2-hexenal, trans-trans-2,4-heptadienal, tyrosol and caffeic acid) could be sampled simultaneously. EVOO data was also compared with that of other edible oils. Principal Component Analysis (PCA) was performed to discriminate EVOO and EVOO adulterated with edible oils. Microjet sampling EESI-MS was found to be a simple, rapid (less than 2 min analysis time per sample) and powerful method to obtain MS fingerprints of EVOO without requiring any complicated sample pretreatment steps.

  16. Rapid determination of ginkgolic acids in Ginkgo biloba kernels and leaves by direct analysis in real time-mass spectrometry.

    Science.gov (United States)

    Huang, Zhongping; Xu, Yueting; Huang, Yilei; Liu, Charles; Jiang, Kezhi; Wang, Lili

    2017-11-14

    A novel method based on direct analysis in real time integrated with mass spectrometry was established and applied into rapid determination of ginkgolic acids in Ginkgo biloba kernels and leaves. Instrument parameter settings were optimized to obtain the sensitive and accurate determination of ginkgolic acids. At the sample introduction speed of 0.2 mm/s, high intensity of [M-H]- ions for ginkgolic acids were observed in the negative ion mode by utilization of high-purity helium gas at 450°C. Two microliters of methanol extract of G. biloba kernels or leaves dropped on the surface of Quick-Strip module was analyzed after solvent evaporated to dryness. A series of standard solutions of ginkgolic acid 13:0 in the range of 2-50 mg/L were analyzed with a correlation coefficient r = 0.9981 and relative standard deviation (n = 5) from 12.5 to 13.7%. The limit of detection was 0.5 mg/L. The results of direct analysis in real time-mass spectrometry were in agreement with those observed by thermochemolysis gas chromatography. The proposed method demonstrated significant potential in the application of the high-throughput screening and rapid analysis for ginkgolic acids in dietary supplements. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Rapid mass spectrometric analysis of 15N-Leu incorporation fidelity during preparation of specifically labeled NMR samples.

    Science.gov (United States)

    Truhlar, Stephanie M E; Cervantes, Carla F; Torpey, Justin W; Kjaergaard, Magnus; Komives, Elizabeth A

    2008-09-01

    Advances in NMR spectroscopy have enabled the study of larger proteins that typically have significant overlap in their spectra. Specific (15)N-amino acid incorporation is a powerful tool for reducing spectral overlap and attaining reliable sequential assignments. However, scrambling of the label during protein expression is a common problem. We describe a rapid method to evaluate the fidelity of specific (15)N-amino acid incorporation. The selectively labeled protein is proteolyzed, and the resulting peptides are analyzed using MALDI mass spectrometry. The (15)N incorporation is determined by analyzing the isotopic abundance of the peptides in the mass spectra using the program DEX. This analysis determined that expression with a 10-fold excess of unlabeled amino acids relative to the (15)N-amino acid prevents the scrambling of the (15)N label that is observed when equimolar amounts are used. MALDI TOF-TOF MS/MS data provide additional information that shows where the "extra" (15)N labels are incorporated, which can be useful in confirming ambiguous assignments. The described procedure provides a rapid technique to monitor the fidelity of selective labeling that does not require a lot of protein. These advantages make it an ideal way of determining optimal expression conditions for selectively labeled NMR samples.

  18. Enhancing Student Learning in Knowledge-Based Courses: Integrating Team-Based Learning in Mass Communication Theory Classes

    Science.gov (United States)

    Han, Gang; Newell, Jay

    2014-01-01

    This study explores the adoption of the team-based learning (TBL) method in knowledge-based and theory-oriented journalism and mass communication (J&MC) courses. It first reviews the origin and concept of TBL, the relevant theories, and then introduces the TBL method and implementation, including procedures and assessments, employed in an…

  19. Rapid characterisation of Klebsiella oxytoca isolates from contaminated liquid hand soap using mass spectrometry, FTIR and Raman spectroscopy.

    Science.gov (United States)

    Dieckmann, Ralf; Hammerl, Jens Andre; Hahmann, Hartmut; Wicke, Amal; Kleta, Sylvia; Dabrowski, Piotr Wojciech; Nitsche, Andreas; Stämmler, Maren; Al Dahouk, Sascha; Lasch, Peter

    2016-06-23

    Microbiological monitoring of consumer products and the efficiency of early warning systems and outbreak investigations depend on the rapid identification and strain characterisation of pathogens posing risks to the health and safety of consumers. This study evaluates the potential of three rapid analytical techniques for identification and subtyping of bacterial isolates obtained from a liquid hand soap product, which has been recalled and reported through the EU RAPEX system due to its severe bacterial contamination. Ten isolates recovered from two bottles of the product were identified as Klebsiella oxytoca and subtyped using matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI TOF MS), near-infrared Fourier transform (NIR FT) Raman spectroscopy and Fourier transform infrared (FTIR) spectroscopy. Comparison of the classification results obtained by these phenotype-based techniques with outcomes of the DNA-based methods pulsed-field gel electrophoresis (PFGE), multi-locus sequence typing (MLST) and single nucleotide polymorphism (SNP) analysis of whole-genome sequencing (WGS) data revealed a high level of concordance. In conclusion, a set of analytical techniques might be useful for rapid, reliable and cost-effective microbial typing to ensure safe consumer products and allow source tracking.

  20. A microfabricated silicon platform with 60 microfluidic chips for rapid mass spectrometric analysis.

    Science.gov (United States)

    Sainiemi, Lauri; Nissilä, Teemu; Kostiainen, Risto; Ketola, Raimo A; Franssila, Sami

    2011-09-07

    This work presents a way of using silicon microfabrication to take advantage of the rim of a silicon wafer in a novel manner. Our circular multichip platform, which is fabricated using only standard microfabrication techniques, has 60 identical miniaturized micropillar array electrospray ionization (μPESI) chips at the periphery of a silicon wafer. The fabricated platform is fixed on a computer controlled rotating table, in front of a mass spectrometer (MS). After each MS measurement an unused μPESI chip is aligned towards the MS by the programmable rotating table. Our wafer-scale platform enabled measurement of 60 samples in 8 minutes. The samples can also be stored on the platform for later analysis.

  1. Electrospray ionization mass spectrometry fingerprinting of perfumes: Rapid classification and counterfeit detection.

    Science.gov (United States)

    Marques, Lygia de Azevedo; Catharino, Rodrigo Ramos; Bruns, Roy E; Eberlin, Marcos N

    2006-01-01

    A fast procedure to classify perfumes and identify counterfeit samples is described. Dilution of a few microL of the sample in a 1:1 methanol/water solution is followed by detection of its major polar components via direct infusion electrospray ionization mass spectrometry (ESI-MS) in the positive ion mode. As proof-of-principle cases, three famous brands of perfumes were used. The ESI+-MS fingerprints of authentic samples were very characteristic, showing distinctive sets of polar markers for each sample. Principal component analysis (PCA) placed samples of the three perfume brands in well-defined groups. Counterfeit samples were also clearly detected owing to contrasting ESI-MS fingerprints, with PCA placing these samples far away from the authentic samples. Copyright 2006 John Wiley & Sons, Ltd.

  2. Learning to rapidly re-contact the lost plume in chemical plume tracing.

    Science.gov (United States)

    Cao, Meng-Li; Meng, Qing-Hao; Wang, Jia-Ying; Luo, Bing; Jing, Ya-Qi; Ma, Shu-Gen

    2015-03-27

    Maintaining contact between the robot and plume is significant in chemical plume tracing (CPT). In the time immediately following the loss of chemical detection during the process of CPT, Track-Out activities bias the robot heading relative to the upwind direction, expecting to rapidly re-contact the plume. To determine the bias angle used in the Track-Out activity, we propose an online instance-based reinforcement learning method, namely virtual trail following (VTF). In VTF, action-value is generalized from recently stored instances of successful Track-Out activities. We also propose a collaborative VTF (cVTF) method, in which multiple robots store their own instances, and learn from the stored instances, in the same database. The proposed VTF and cVTF methods are compared with biased upwind surge (BUS) method, in which all Track-Out activities utilize an offline optimized universal bias angle, in an indoor environment with three different airflow fields. With respect to our experimental conditions, VTF and cVTF show stronger adaptability to different airflow environments than BUS, and furthermore, cVTF yields higher success rates and time-efficiencies than VTF.

  3. Learning to Rapidly Re-Contact the Lost Plume in Chemical Plume Tracing

    Directory of Open Access Journals (Sweden)

    Meng-Li Cao

    2015-03-01

    Full Text Available Maintaining contact between the robot and plume is significant in chemical plume tracing (CPT. In the time immediately following the loss of chemical detection during the process of CPT, Track-Out activities bias the robot heading relative to the upwind direction, expecting to rapidly re-contact the plume. To determine the bias angle used in the Track-Out activity, we propose an online instance-based reinforcement learning method, namely virtual trail following (VTF. In VTF, action-value is generalized from recently stored instances of successful Track-Out activities. We also propose a collaborative VTF (cVTF method, in which multiple robots store their own instances, and learn from the stored instances, in the same database. The proposed VTF and cVTF methods are compared with biased upwind surge (BUS method, in which all Track-Out activities utilize an offline optimized universal bias angle, in an indoor environment with three different airflow fields. With respect to our experimental conditions, VTF and cVTF show stronger adaptability to different airflow environments than BUS, and furthermore, cVTF yields higher success rates and time-efficiencies than VTF.

  4. Learning to Rapidly Re-Contact the Lost Plume in Chemical Plume Tracing

    Science.gov (United States)

    Cao, Meng-Li; Meng, Qing-Hao; Wang, Jia-Ying; Luo, Bing; Jing, Ya-Qi; Ma, Shu-Gen

    2015-01-01

    Maintaining contact between the robot and plume is significant in chemical plume tracing (CPT). In the time immediately following the loss of chemical detection during the process of CPT, Track-Out activities bias the robot heading relative to the upwind direction, expecting to rapidly re-contact the plume. To determine the bias angle used in the Track-Out activity, we propose an online instance-based reinforcement learning method, namely virtual trail following (VTF). In VTF, action-value is generalized from recently stored instances of successful Track-Out activities. We also propose a collaborative VTF (cVTF) method, in which multiple robots store their own instances, and learn from the stored instances, in the same database. The proposed VTF and cVTF methods are compared with biased upwind surge (BUS) method, in which all Track-Out activities utilize an offline optimized universal bias angle, in an indoor environment with three different airflow fields. With respect to our experimental conditions, VTF and cVTF show stronger adaptability to different airflow environments than BUS, and furthermore, cVTF yields higher success rates and time-efficiencies than VTF. PMID:25825974

  5. Learning new color names produces rapid increase in gray matter in the intact adult human cortex.

    Science.gov (United States)

    Kwok, Veronica; Niu, Zhendong; Kay, Paul; Zhou, Ke; Mo, Lei; Jin, Zhen; So, Kwok-Fai; Tan, Li Hai

    2011-04-19

    The human brain has been shown to exhibit changes in the volume and density of gray matter as a result of training over periods of several weeks or longer. We show that these changes can be induced much faster by using a training method that is claimed to simulate the rapid learning of word meanings by children. Using whole-brain magnetic resonance imaging (MRI) we show that learning newly defined and named subcategories of the universal categories green and blue in a period of 2 h increases the volume of gray matter in V2/3 of the left visual cortex, a region known to mediate color vision. This pattern of findings demonstrates that the anatomical structure of the adult human brain can change very quickly, specifically during the acquisition of new, named categories. Also, prior behavioral and neuroimaging research has shown that differences between languages in the boundaries of named color categories influence the categorical perception of color, as assessed by judgments of relative similarity, by response time in alternative forced-choice tasks, and by visual search. Moreover, further behavioral studies (visual search) and brain imaging studies have suggested strongly that the categorical effect of language on color processing is left-lateralized, i.e., mediated by activity in the left cerebral hemisphere in adults (hence "lateralized Whorfian" effects). The present results appear to provide a structural basis in the brain for the behavioral and neurophysiologically observed indices of these Whorfian effects on color processing.

  6. Rapid characterization of chemical compounds in liquid and solid states using thermal desorption electrospray ionization mass spectrometry.

    Science.gov (United States)

    Huang, Min-Zong; Zhou, Chi-Chang; Liu, De-Lin; Jhang, Siou-Sian; Cheng, Sy-Chyi; Shiea, Jentaie

    2013-10-01

    Rapid characterization of thermally stable chemical compounds in solid or liquid states is achieved through thermal desorption electrospray ionization mass spectrometry (TD-ESI/MS). A feature of this technique is that sampling, desorption, ionization, and mass spectrometric detection are four separate events with respect to time and location. A metal probe was used to sample analytes in their solid or liquid states. The probe was then inserted in a preheated oven to thermally desorb the analytes on the probe. The desorbed analytes were carried by a nitrogen gas stream into an ESI plume, where analyte ions were formed via interactions with charged solvent species generated in the ESI plume. The analyte ions were subsequently detected by a mass analyzer attached to the TD-ESI source. Quantification of acetaminophen in aqueous solutions using TD-ESI/MS was also performed in which a linear response for acetaminophen was obtained between 25 and 500 ppb (R(2) = 0.9978). The standard deviation for a reproducibility test for ten liquid samples was 9.6%. Since sample preparation for TD-ESI/MS is unnecessary, a typical analysis can be completed in less than 10 s. Analytes such as the active ingredients in over-the-counter drugs were rapidly characterized regardless of the different physical properties of said drugs, which included liquid eye drops, viscous cold syrup solution, ointment cream, and a drug tablet. This approach was also used to detect trace chemical compounds in illicit drugs and explosives, in which samples were obtained from the surfaces of a cell phone, piece of luggage made from hard plastic, business card, and wooden desk.

  7. Toward rapid learning in cancer treatment selection: An analytical engine for practice-based clinical data.

    Science.gov (United States)

    Finlayson, Samuel G; Levy, Mia; Reddy, Sunil; Rubin, Daniel L

    2016-04-01

    Wide-scale adoption of electronic medical records (EMRs) has created an unprecedented opportunity for the implementation of Rapid Learning Systems (RLSs) that leverage primary clinical data for real-time decision support. In cancer, where large variations among patient features leave gaps in traditional forms of medical evidence, the potential impact of a RLS is particularly promising. We developed the Melanoma Rapid Learning Utility (MRLU), a component of the RLS, providing an analytical engine and user interface that enables physicians to gain clinical insights by rapidly identifying and analyzing cohorts of patients similar to their own. A new approach for clinical decision support in Melanoma was developed and implemented, in which patient-centered cohorts are generated from practice-based evidence and used to power on-the-fly stratified survival analyses. A database to underlie the system was generated from clinical, pharmaceutical, and molecular data from 237 patients with metastatic melanoma from two academic medical centers. The system was assessed in two ways: (1) ability to rediscover known knowledge and (2) potential clinical utility and usability through a user study of 13 practicing oncologists. The MRLU enables physician-driven cohort selection and stratified survival analysis. The system successfully identified several known clinical trends in melanoma, including frequency of BRAF mutations, survival rate of patients with BRAF mutant tumors in response to BRAF inhibitor therapy, and sex-based trends in prevalence and survival. Surveyed physician users expressed great interest in using such on-the-fly evidence systems in practice (mean response from relevant survey questions 4.54/5.0), and generally found the MRLU in particular to be both useful (mean score 4.2/5.0) and useable (4.42/5.0). The MRLU is an RLS analytical engine and user interface for Melanoma treatment planning that presents design principles useful in building RLSs. Further research is

  8. Development of a Rapid Microbore Metabolic Profiling Ultraperformance Liquid Chromatography-Mass Spectrometry Approach for High-Throughput Phenotyping Studies.

    Science.gov (United States)

    Gray, Nicola; Adesina-Georgiadis, Kyrillos; Chekmeneva, Elena; Plumb, Robert S; Wilson, Ian D; Nicholson, Jeremy K

    2016-06-07

    A rapid gradient microbore ultraperformance liquid chromatography-mass spectrometry (UPLC-MS) method has been developed to provide a high-throughput analytical platform for the metabolic phenotyping of urine from large sample cohorts. The rapid microbore metabolic profiling (RAMMP) approach was based on scaling a conventional reversed-phase UPLC-MS method for urinary profiling from 2.1 mm × 100 mm columns to 1 mm × 50 mm columns, increasing the linear velocity of the solvent, and decreasing the gradient time to provide an analysis time of 2.5 min/sample. Comparison showed that conventional UPLC-MS and rapid gradient approaches provided peak capacities of 150 and 50, respectively, with the conventional method detecting approximately 19 000 features compared to the ∼6 000 found using the rapid gradient method. Similar levels of repeatability were seen for both methods. Despite the reduced peak capacity and the reduction in ions detected, the RAMMP method was able to achieve similar levels of group discrimination as conventional UPLC-MS when applied to rat urine samples obtained from investigative studies on the effects of acute 2-bromophenol and chronic acetaminophen administration. When compared to a direct infusion MS method of similar analysis time the RAMMP method provided superior selectivity. The RAMMP approach provides a robust and sensitive method that is well suited to high-throughput metabonomic analysis of complex mixtures such as urine combined with a 5-fold reduction in analysis time compared with the conventional UPLC-MS method.

  9. Rapid identification of regulated organic chemical compounds in toys using ambient ionization and a miniature mass spectrometry system.

    Science.gov (United States)

    Guo, Xiangyu; Bai, Hua; Lv, Yueguang; Xi, Guangcheng; Li, Junfang; Ma, Xiaoxiao; Ren, Yue; Ouyang, Zheng; Ma, Qiang

    2018-04-01

    Rapid, on-site analysis was achieved through significantly simplified operation procedures for a wide variety of toy samples (crayon, temporary tattoo sticker, finger paint, modeling clay, and bubble solution) using a miniature mass spectrometry system with ambient ionization capability. The labor-intensive analytical protocols involving sample workup and chemical separation, traditionally required for MS-based analysis, were replaced by direct sampling analysis using ambient ionization methods. A Mini β ion trap miniature mass spectrometer was coupled with versatile ambient ionization methods, e.g. paper spray, extraction spray and slug-flow microextraction nanoESI for direct identification of prohibited colorants, carcinogenic primary aromatic amines, allergenic fragrances, preservatives and plasticizers from raw toy samples. The use of paper substrates coated with Co 3 O 4 nanoparticles allowed a great increase in sensitivity for paper spray. Limits of detection as low as 5μgkg -1 were obtained for target analytes. The methods being developed based on the integration of ambient ionization with miniature mass spectrometer represent alternatives to current in-lab MS analysis operation, and would enable fast, outside-the-lab screening of toy products to ensure children's safety and health. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Rapid screening and characterisation of antioxidants of Cosmos caudatus using liquid chromatography coupled with mass spectrometry.

    Science.gov (United States)

    Shui, Guanghou; Leong, Lai Peng; Wong, Shih Peng

    2005-11-15

    Ulam raja (Cosmos caudatus) is used traditionally for improving blood circulation. In this study, it was found that ulam raja had extremely high antioxidant capacity of about 2,400 mg l-ascorbic acid equivalent antioxidant capacity (AEAC) per 100 g of fresh sample. Antioxidant peaks in extract of ulam raja were firstly characterized using free radical spiking test through high performance liquid chromatography coupled with mass spectrometry (MS). Upon reaction with 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) free radicals, intensities of antioxidant peaks will be significantly reduced. HPLC/MS(n) was further applied to elucidate the chemical structures of antioxidant peaks characterized in the spiking test. More than twenty antioxidants were identified in ulam raja, and their chemical structures were proposed. The major antioxidants in ulam raja were attributed to a number of proanthocyanidins that existed as dimers through hexamers, quercetin glycosides, chlorogenic, neo-chlorogenic, crypto-chlorogenic acid and (+)-catching. High content of antioxidants antioxidants contained in ulam raja could be partly responsible for its ability to reduce oxidative stress.

  11. Rapid characterization of biotherapeutic proteins by size-exclusion chromatography coupled to native mass spectrometry.

    Science.gov (United States)

    Haberger, Markus; Leiss, Michael; Heidenreich, Anna-Katharina; Pester, Oxana; Hafenmair, Georg; Hook, Michaela; Bonnington, Lea; Wegele, Harald; Haindl, Markus; Reusch, Dietmar; Bulau, Patrick

    2016-01-01

    High-molecular weight aggregates such as antibody dimers and other side products derived from incorrect light or heavy chain association typically represent critical product-related impurities for bispecific antibody formats. In this study, an approach employing ultra-pressure liquid chromatography size-exclusion separation combined with native electrospray ionization mass spectrometry for the simultaneous formation, identification and quantification of size variants in recombinant antibodies was developed. Samples exposed to storage and elevated temperature(s) enabled the identification of various bispecific antibody size variants. This test system hence allowed us to study the variants formed during formulation and bio-process development, and can thus be transferred to quality control units for routine in-process control and release analytics. In addition, native SEC-UV/MS not only facilitates the detailed analysis of low-abundant and non-covalent size variants during process characterization/validation studies, but is also essential for the SEC-UV method validation prior to admission to the market.

  12. Mass spectrometry proteomics: Ready for the deep learning (r)evolution?

    OpenAIRE

    Bittremieux, Wout; Laukens, Kris

    2017-01-01

    In the past few years deep learning (DL) has revolutionized machine learning research, achieving tremendous increases in performance on a variety of problems, ranging from image recognition to natural language processing. In bioinformatics deep neural networks have already been used to solve important problems in genomics, but they have not seen a lot of use in biological mass spectrometry (MS) yet. Nevertheless, there is a huge opportunity to apply DL to MS research as well. Here we show how...

  13. A SIMPLE AND RAPID MATRIX-ASSISTED LASER DESORPTION/IONIZATION TIME OF FLIGHT MASS SPECTROMETRY METHOD TO SCREEN FISH PLASMA SAMPLES FOR ESTROGEN-RESPONSIVE BIOMARKERS

    Science.gov (United States)

    In this study, we describe and evaluate the performance of a simple and rapid mass spectral method for screening fish plasma for estrogen-responsive biomarkers using matrix assisted laster desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS) couopled with a short...

  14. Rapid Quadrupole-Time-of-Flight Mass Spectrometry Method Quantifies Oxygen-Rich Lignin Compound in Complex Mixtures

    Science.gov (United States)

    Boes, Kelsey S.; Roberts, Michael S.; Vinueza, Nelson R.

    2017-12-01

    Complex mixture analysis is a costly and time-consuming task facing researchers with foci as varied as food science and fuel analysis. When faced with the task of quantifying oxygen-rich bio-oil molecules in a complex diesel mixture, we asked whether complex mixtures could be qualitatively and quantitatively analyzed on a single mass spectrometer with mid-range resolving power without the use of lengthy separations. To answer this question, we developed and evaluated a quantitation method that eliminated chromatography steps and expanded the use of quadrupole-time-of-flight mass spectrometry from primarily qualitative to quantitative as well. To account for mixture complexity, the method employed an ionization dopant, targeted tandem mass spectrometry, and an internal standard. This combination of three techniques achieved reliable quantitation of oxygen-rich eugenol in diesel from 300 to 2500 ng/mL with sufficient linearity (R2 = 0.97 ± 0.01) and excellent accuracy (percent error = 0% ± 5). To understand the limitations of the method, it was compared to quantitation attained on a triple quadrupole mass spectrometer, the gold standard for quantitation. The triple quadrupole quantified eugenol from 50 to 2500 ng/mL with stronger linearity (R2 = 0.996 ± 0.003) than the quadrupole-time-of-flight and comparable accuracy (percent error = 4% ± 5). This demonstrates that a quadrupole-time-of-flight can be used for not only qualitative analysis but also targeted quantitation of oxygen-rich lignin molecules in complex mixtures without extensive sample preparation. The rapid and cost-effective method presented here offers new possibilities for bio-oil research, including: (1) allowing for bio-oil studies that demand repetitive analysis as process parameters are changed and (2) making this research accessible to more laboratories. [Figure not available: see fulltext.

  15. [Rapid determination of alkaloids in tobacco using gas chromatography-mass spectrometry with full scan-selected ion monitoring mode].

    Science.gov (United States)

    Wang, Baoxing; Yang, Shihua; Hou, Ying; Zeng, Xiaoying; Wu, Yi; Xu, Guowang

    2008-05-01

    Simultaneous full scan-selected ion monitoring mode (Scan-SIM) is a new improvement method of data acquisition of gas chromatography-mass spectrometry (GC-MS). A method of determing alkaloids in tobacco was established by GC-MS with Scan-SIM. Nicotine, nornicotine, anabasine and anatabine were determined with scan mode, and myosmine, nicotyrine, 2,3'-bipyridyl and cotinine were determined with SIM mode. The average recoveries of alkaloids ranged from 94.8% to 98.8%, and the relative standard deviations were less than 6.0% (n = 5). Therefore, it is a simple, rapid, accurate method. Tobacco samples picked in different years were determined using this method, and the results were satisfactory.

  16. Rapid identification of molecular changes in tulsi (Ocimum sanctum Linn) upon ageing using leaf spray ionization mass spectrometry.

    Science.gov (United States)

    Sarkar, Depanjan; Srimany, Amitava; Pradeep, T

    2012-10-07

    Tulsi or Holy Basil (Ocimum sanctum Linn) is a medicinally important plant. Ursolic acid (UA) and oleanolic acid (OA) are among its major constituents which account for many medicinal activities of the plant. In the present work, we deployed a new ambient ionization method, leaf spray ionization, for rapid detection of UA, OA and their oxidation products from tulsi leaves. Tandem electrospray ionization mass spectrometry (ESI-MS) has been performed on tulsi leaf extracts in methanol to establish the identity of the compounds. We probed changes occurring in the relative amounts of the parent compounds (UA and OA) with their oxidized products and the latter show an increasing trend upon ageing. The findings are verified by ESI-MS analysis of tulsi leaf extracts, which shows the same trend proving the reliability of the leaf spray method.

  17. Rapid Analysis of Bisphenol A and Its Analogues in Food Packaging Products by Paper Spray Ionization Mass Spectrometry.

    Science.gov (United States)

    Chen, Shuo; Chang, Quanying; Yin, Kai; He, Qunying; Deng, Yongxiu; Chen, Bo; Liu, Chengbin; Wang, Ying; Wang, Liping

    2017-06-14

    In this study, a paper spray ionization mass spectrometric (PS-MS) method was developed for the rapid in situ screening and simultaneous quantitative analysis of bisphenol A and its analogues, i.e., bisphenol S, bisphenol F, and bisphenol AF, in food packaging products. At the optimal PS-MS conditions, the calibration curves of bisphenols in the range of 1-100 μg/mL were linear. The correlation coefficients were higher than 0.998, and the LODs of the target compounds were 0.1-0.3 μg/mL. After a simple treatment by dichloromethane on the surface, the samples were analyzed by PS-MS in situ for rapid screening without a traditional sample pretreatment procedure, such as powdering, extraction, and enrichment steps. The analytical time of the PS-MS method was less than 1 min. In comparison with conventional HPLC-MS/MS, it was demonstrated that PS-MS was a more effective high-throughput screening and quantitative analysis method.

  18. A rapid quantitative method for the analysis of synthetic cannabinoids by liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Freijo, Tom D; Harris, Steve E; Kala, Subbarao V

    2014-10-01

    Synthetic cannabinoids represent an emerging drug problem in the USA, as these compounds are constantly being modified and rapidly sold as soon as they become available. Laboratories around the world are constantly improving the analytical methods to detect and identify these newly available designer drugs. This study used a simple approach to detect and quantify a variety of synthetic cannabinoids (14 parent compounds and 15 metabolites including series XLR, AM, JWH, UR, RCS, PB, HU and AB-FUBINACA) using LC-MS-MS. Drug-free urine samples spiked with various synthetic cannabinoids and their metabolites were separated on a C18-Hypersil Gold column using an Agilent 1290 ultra-high performance liquid chromatography and detected by an AB Sciex API 4000 tandem mass spectrometer. Studies were carried out to determine limit of detection, limit of quantitation, upper limit of linearity, ion suppression, interference, precision and accuracy to validate the method. Urine samples from patients and known users were hydrolyzed with β-glucuronidase prior to the analysis by LC-MS-MS, and the data are presented. The method described here is rapid, highly sensitive and specific for the identification of a variety of synthetic cannabinoids. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  19. Rapid detection of sugar alcohol precursors and corresponding nitrate ester explosives using direct analysis in real time mass spectrometry.

    Science.gov (United States)

    Sisco, Edward; Forbes, Thomas P

    2015-04-21

    This work highlights the rapid detection of nitrate ester explosives and their sugar alcohol precursors by direct analysis in real time mass spectrometry (DART-MS) using an off-axis geometry. Demonstration of the effect of various parameters, such as ion polarity and in-source collision induced dissociation (CID) on the detection of these compounds is presented. Sensitivity of sugar alcohols and nitrate ester explosives was found to be greatest in negative ion mode with sensitivities ranging from hundreds of picograms to hundreds of nanograms, depending on the characteristics of the particular molecule. Altering the in-source CID potential allowed for acquisition of characteristic molecular ion spectra as well as fragmentation spectra. Additional studies were completed to identify the role of different experimental parameters on the sensitivity for these compounds. Variables that were examined included the DART gas stream temperature, the presence of a related compound (i.e., the effect of a precursor on the detection of a nitrate ester explosive), incorporation of dopant species and the role of the analysis surface. It was determined that each variable affected the response and detection of both sugar alcohols and the corresponding nitrate ester explosives. From this work, a rapid and sensitive method for the detection of individual sugar alcohols and corresponding nitrate ester explosives, or mixtures of the two, has been developed, providing a useful tool in the real-world identification of homemade explosives.

  20. Optimization of Analytical Conditions for a Rapid Determination of Aniline in Environmental Water by Liquid Chromatography/Tandem Mass Spectrometry.

    Science.gov (United States)

    Furukawa, Koji; Hashimoto, Makoto; Kaneco, Satoshi

    2017-01-01

    A rapid determination of aniline in environmental water was examined based on liquid chromatography/tandem mass spectrometry (LC/MS/MS). Environmental water samples were diluted 20-fold with Mill-Q water and measured by LC/MS/MS after adding a surrogate substance (aniline-d5). In the results of the present study, the calibration curve of aniline showed good linearity in the range of 0.05 - 2.0 μg/L. Since the RSD (repeatability) by measuring repeatedly an aniline standard solution (0.05 μg/L, n = 7) was 3.2%, the repeatability of this work was very excellent. In addition, the recovery rate of aniline in environmental water was in the range of 99.0 - 102% with RSD 3.4 - 7.7%, and very good recovery test results were obtained. From these results, this analytical method was confirmed to be effective for aniline measurements of environmental water samples. Also, it is possible to conduct rapid analyses of aniline in environmental water without any solid-phase extraction process, compared to the solid-phase extraction-GC/MS method.

  1. Rapidly increasing body mass index among children, adolescents and young adults in a transitioning population, South Africa, 2008-15.

    Science.gov (United States)

    Sartorius, B; Sartorius, K; Taylor, M; Aagaard-Hansen, J; Dukhi, N; Day, C; Ndlovu, N; Slotow, R; Hofman, K

    2017-12-14

    There is a global epidemic of overweight and obesity; however, this rate of increase is even greater in some low- and middle-income countries (LMIC). South Africa (SA) is undergoing rapid socioeconomic and demographic changes that have triggered a rapid nutrition transition. The paper focuses on the recent rate of change of body mass index (BMI) among children, adolescents and young adults, further stratified by key sociodemographic factors. We analysed mean BMI of 28 247 individuals (including children) from 7301 households by age and year, from anthropometric data from four national cross-sectional (repeated panel) surveys using non-linear fitted curves and associated 95% confidence intervals. From 2008 to 2015, there was rapid rise in mean BMI in the 6-25 age band, with the highest risk (3-4+ BMI unit increase) among children aged 8-10 years. The increase was largely among females in urban areas and of middle-high socioeconomic standing. Prominent gains were also observed in certain rural areas, with extensive geographical heterogeneity across the country. We have demonstrated a major deviation from the current understanding of patterns of BMI increase, with a rate of increase substantially greater in the developing world context compared with the global pattern. This population-wide effect will have major consequences for national development as the epidemic of related non-communicable disease unfolds, and will overtax the national health care budget. Our refined understanding highlights that risks are further compounded for certain groups/places, and emphasizes that urgent geographical and population-targeted interventions are necessary. These interventions could include a sugar tax, clearer food labelling, revised school feeding programmes and mandatory bans on unhealthy food marketing to children.The scenario unfolding in South Africa will likely be followed in other LMICs.

  2. Perspectives of Patients With Cancer on the Ethics of Rapid-Learning Health Systems.

    Science.gov (United States)

    Jagsi, Reshma; Griffith, Kent A; Sabolch, Aaron; Jones, Rochelle; Spence, Rebecca; De Vries, Raymond; Grande, David; Bradbury, Angela R

    2017-07-10

    Purpose To inform the evolving implementation of CancerLinQ and other rapid-learning systems for oncology care, we sought to evaluate perspectives of patients with cancer regarding ethical issues. Methods Using the GfK Group online research panel, representative of the US population, we surveyed 875 patients with cancer; 621 (71%) responded. We evaluated perceptions of appropriateness (scored from 1 to 10; 10, very appropriate) using scenarios and compared responses by age, race, and education. We constructed a scaled measure of comfort with secondary use of deidentified medical information and evaluated its correlates in a multivariable model. Results Of the sample, 9% were black and 9% Hispanic; 38% had completed high school or less, and 59% were age ≥ 65 years. Perceptions of appropriateness were highest when consent was obtained and university researchers used data to publish a research study (weighted mean appropriateness, 8.47) and lowest when consent was not obtained and a pharmaceutical company used data for marketing (weighted mean appropriateness, 2.7). Most respondents (72%) thought secondary use of data for research was very important, although those with lower education were less likely to endorse this (62% v 78%; P information from medical records varied by scenario and overall was associated with distrust in the health care system. Conclusion Perceptions of patients with cancer regarding secondary data use depend on the user and the specific use of the data, while also frequently differing by patient sociodemographic factors. Such information is critical to inform ongoing efforts to implement oncology learning systems.

  3. Fourier Transform Mass Spectrometry and Nuclear Magnetic Resonance Analysis for the Rapid and Accurate Characterization of Hexacosanoylceramide.

    Science.gov (United States)

    Ross, Charles W; Simonsick, William J; Bogusky, Michael J; Celikay, Recep W; Guare, James P; Newton, Randall C

    2016-06-28

    Ceramides are a central unit of all sphingolipids which have been identified as sites of biological recognition on cellular membranes mediating cell growth and differentiation. Several glycosphingolipids have been isolated, displaying immunomodulatory and anti-tumor activities. These molecules have generated considerable interest as potential vaccine adjuvants in humans. Accurate analyses of these and related sphingosine analogues are important for the characterization of structure, biological function, and metabolism. We report the complementary use of direct laser desorption ionization (DLDI), sheath flow electrospray ionization (ESI) Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS) and high-field nuclear magnetic resonance (NMR) analysis for the rapid, accurate identification of hexacosanoylceramide and starting materials. DLDI does not require stringent sample preparation and yields representative ions. Sheath-flow ESI yields ions of the product and byproducts and was significantly better than monospray ESI due to improved compound solubility. Negative ion sheath flow ESI provided data of starting materials and products all in one acquisition as hexacosanoic acid does not ionize efficiently when ceramides are present. NMR provided characterization of these lipid molecules complementing the results obtained from MS analyses. NMR data was able to differentiate straight chain versus branched chain alkyl groups not easily obtained from mass spectrometry.

  4. Rapid assignment of malting barley varieties by matrix-assisted laser desorption-ionisation - Time-of-flight mass spectrometry.

    Science.gov (United States)

    Šedo, Ondrej; Kořán, Michal; Jakešová, Michaela; Mikulíková, Renata; Boháč, Michal; Zdráhal, Zbyněk

    2016-09-01

    A method for discriminating malting barley varieties based on direct matrix-assisted laser desorption-ionisation - time-of-flight mass spectrometry (MALDI-TOF MS) fingerprinting of proteins was developed. Signals corresponding to hordeins were obtained by simple mixing of powdered barley grain with a MALDI matrix solution containing 12.5mgmL(-1) of ferulic acid in an acetonitrile:water:formic acid 50:33:17 v/v/v mixture. Compared to previous attempts at MALDI-TOF mass spectrometric analysis of barley proteins, the extraction and fractionation steps were practically omitted, resulting in a significant reduction in analytical time and costs. The discriminatory power was examined on twenty malting barley varieties and the practicability of the method was tested on sixty barley samples acquired from Pilsner Urquell Brewery. The method is proposed as a rapid tool for variety assignment and purity determination of malting barley that may replace gel electrophoresis currently used for this purpose. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Rapid and sensitive liquid chromatography tandem mass spectrometry method for the quantification of ambroxol in human plasma.

    Science.gov (United States)

    Hu, Wanqun; Xu, Yu; Liu, Fei; Liu, Aixiang; Guo, Qingxiang

    2008-10-01

    A sensitive, specific and rapid high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was described and validated for the quantification of ambroxol in human plasma using enalaprilat as the internal standard (IS). Chromatographic separation was performed on a Lichrospher CN column with a mobile phase of methanol and water (containing 0.1% formic acid) (70:30, v/v). The total run time was 5.0 min for each sample. The analytes was detected by mass spectrometry with electrospray ionization source in positive selected reaction monitoring mode. The precursor-fragment ion reaction for ambroxol was m/z 378.9 --> 263.8, and for IS was m/z 349.0 --> 205.9. The linearity was established over the concentration range of 1.56-400.00 ng/mL. The inter-day and the intra-day precisions were all within 10%. A simple protein precipitation with methanol was adopted for sample preparation. The extraction recoveries of ambroxol and IS were higher than 90.80%. The validated method was successfully applied in pharmacokinetic study after oral administration of 90 mg ambroxol to 24 healthy volunteers.

  6. Fourier Transform Mass Spectrometry and Nuclear Magnetic Resonance Analysis for the Rapid and Accurate Characterization of Hexacosanoylceramide

    Directory of Open Access Journals (Sweden)

    Charles W. Ross

    2016-06-01

    Full Text Available Ceramides are a central unit of all sphingolipids which have been identified as sites of biological recognition on cellular membranes mediating cell growth and differentiation. Several glycosphingolipids have been isolated, displaying immunomodulatory and anti-tumor activities. These molecules have generated considerable interest as potential vaccine adjuvants in humans. Accurate analyses of these and related sphingosine analogues are important for the characterization of structure, biological function, and metabolism. We report the complementary use of direct laser desorption ionization (DLDI, sheath flow electrospray ionization (ESI Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS and high-field nuclear magnetic resonance (NMR analysis for the rapid, accurate identification of hexacosanoylceramide and starting materials. DLDI does not require stringent sample preparation and yields representative ions. Sheath-flow ESI yields ions of the product and byproducts and was significantly better than monospray ESI due to improved compound solubility. Negative ion sheath flow ESI provided data of starting materials and products all in one acquisition as hexacosanoic acid does not ionize efficiently when ceramides are present. NMR provided characterization of these lipid molecules complementing the results obtained from MS analyses. NMR data was able to differentiate straight chain versus branched chain alkyl groups not easily obtained from mass spectrometry.

  7. Extranodal NK/T-cell lymphoma, nasal type, manifesting as rapidly progressive dementia without any mass or enhancing brain lesion.

    Science.gov (United States)

    Shimatani, Yoshimitsu; Nakano, Yuta; Tsuyama, Naoko; Murayama, Shigeo; Oki, Ryosuke; Miyamoto, Ryosuke; Murakami, Nagahisa; Fujita, Koji; Watanabe, Syunsuke; Uehara, Hisanori; Abe, Takashi; Nodera, Hiroyuki; Kawarai, Toshitaka; Izumi, Yuishin; Kaji, Ryuji

    2016-10-01

    Among the many potential etiologies for rapidly progressive dementia (RPD), primary central nervous system extranodal NK/T-cell lymphoma, nasal-type (ENKL) is a rare entity. We present the first reported case of autopsy-proven RPD due to ENKL without any mass or enhancing lesion of the brain. A 54-year-old immunocompetent man presented with RPD, myoclonus and ataxia. The mini-mental state examination (MMSE) score was 22/30. His brain MRI revealed progressive brain atrophy without gadolinium enhancement or mass lesion. Five months after the initial evaluation, cognitive impairment further worsened with an MMSE score of 3/30. At the advanced stage, lumbar MRI showed swollen cauda equina with gadolinium enhancement. The number of Epstein-Barr virus (EBV) DNA in cerebrospinal fluid had gradually increased. Twelve months after onset, the patient died of respiratory failure. Pathological findings revealed that lymphoma cells had diffusely invaded the meninges, parenchyma of the brain, spinal cord and cauda equina. Cells were positive for CD3, CD56 and EBV-encoded small RNAs and negative for CD20. No evidence of malignancy was identified in the visceral organs. This report indicates that ENKL should be recognized as one of the rare causes of RPD. Early testing for EBV-DNA in cerebrospinal fluid and imaging of cauda equina would be useful diagnostic tools. © 2016 Japanese Society of Neuropathology.

  8. Desorption electrospray ionisation mass spectrometry: A rapid screening tool for veterinary drug preparations and forensic samples from hormone crime investigations

    Energy Technology Data Exchange (ETDEWEB)

    Nielen, M.W.F. [RIKILT Institute of Food Safety, P.O. Box 230, 6700 AE Wageningen (Netherlands); Wageningen University, Laboratory of Organic Chemistry, Dreijenplein 8, 6703 HB Wageningen (Netherlands)], E-mail: michel.nielen@wur.nl; Hooijerink, H. [RIKILT Institute of Food Safety, P.O. Box 230, 6700 AE Wageningen (Netherlands); Claassen, F.C. [Wageningen University, Laboratory of Organic Chemistry, Dreijenplein 8, 6703 HB Wageningen (Netherlands); Engelen, M.C. van [RIKILT Institute of Food Safety, P.O. Box 230, 6700 AE Wageningen (Netherlands); Beek, T.A. van [Wageningen University, Laboratory of Organic Chemistry, Dreijenplein 8, 6703 HB Wageningen (Netherlands)

    2009-04-01

    Hormone and veterinary drug screening and forensics can benefit from the recent developments in desorption electrospray ionisation (DESI) mass spectrometry (MS). In this work the feasibility of DESI application has been studied. Using a linear ion trap or quadrupole time-of-flight (TOF) MS instrument both full-scan and data-dependent collision-induced dissociation MS{sup n} spectra were acquired in seconds without sample preparation. Preliminary data are presented for the rapid screening of (pro)hormone supplement samples, an illegal steroid cocktail and forensic samples from veterinary drug investigations. The potential of this DESI approach is clearly demonstrated since compounds observed could be independently confirmed by liquid chromatography/TOFMS with accurate mass measurement, and/or proton nuclear magnetic resonance spectroscopy. Specific concerns related to false-positive and false-negative findings due to limitations in quantification and memory-effects are briefly discussed. It is envisaged that DESI will achieve a prominent role in hormone and veterinary drug analysis in the near future.

  9. Assessing the Merits of International Service-Learning in Developing Professionalism in Mass Communication

    Science.gov (United States)

    Motley, Phillip; Sturgill, Amanda

    2013-01-01

    This project assessed how an international service-learning course affected mass communication students' knowledge of professionalism. Using written reflections and focus group transcripts from four courses that took place in Central America, we observed that placing students in immersive environments, where they are able to work on authentic…

  10. Machine-z: Rapid Machine-Learned Redshift Indicator for Swift Gamma-Ray Bursts

    Science.gov (United States)

    Ukwatta, T. N.; Wozniak, P. R.; Gehrels, N.

    2016-01-01

    Studies of high-redshift gamma-ray bursts (GRBs) provide important information about the early Universe such as the rates of stellar collapsars and mergers, the metallicity content, constraints on the re-ionization period, and probes of the Hubble expansion. Rapid selection of high-z candidates from GRB samples reported in real time by dedicated space missions such as Swift is the key to identifying the most distant bursts before the optical afterglow becomes too dim to warrant a good spectrum. Here, we introduce 'machine-z', a redshift prediction algorithm and a 'high-z' classifier for Swift GRBs based on machine learning. Our method relies exclusively on canonical data commonly available within the first few hours after the GRB trigger. Using a sample of 284 bursts with measured redshifts, we trained a randomized ensemble of decision trees (random forest) to perform both regression and classification. Cross-validated performance studies show that the correlation coefficient between machine-z predictions and the true redshift is nearly 0.6. At the same time, our high-z classifier can achieve 80 per cent recall of true high-redshift bursts, while incurring a false positive rate of 20 per cent. With 40 per cent false positive rate the classifier can achieve approximately 100 per cent recall. The most reliable selection of high-redshift GRBs is obtained by combining predictions from both the high-z classifier and the machine-z regressor.

  11. Method Development for Rapid Analysis of Natural Radioactive Nuclides Using Sector Field Inductively Coupled Plasma Mass Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Lim, J.M.; Ji, Y.Y.; Lee, H.; Park, J.H.; Jang, M.; Chung, K.H.; Kang, M.J.; Choi, G.S. [Korea Atomic Energy Research Institute (Korea, Republic of)

    2014-07-01

    As an attempt to reduce the social costs and apprehension arising from radioactivity in the environment, an accurate and rapid assessment of radioactivity is highly desirable. Naturally occurring radioactive materials (NORM) are widely spread throughout the environment. The concern with radioactivity from these materials has therefore been growing for the last decade. In particular, radiation exposure in the industry when handling raw materials (e.g., coal mining and combustion, oil and gas production, metal mining and smelting, mineral sands (REE, Ti, Zr), fertilizer (phosphate), and building materials) has been brought to the public's attention. To decide the proper handling options, a rapid and accurate analytical method that can be used to evaluate the radioactivity of radionuclides (e.g., {sup 238}U, {sup 235}U, {sup 232}Th, {sup 226}Ra, and {sup 40}K) should be developed and validated. Direct measuring methods such as alpha spectrometry, a liquid scintillation counter (LSC), and mass-spectrometry are usually used for the measurement of radioactivity in NORM samples, and they encounter the most significant difficulties during pretreatment (e.g., purification, speciation, and dilution/enrichment). Since the pretreatment process consequently plays an important role in the measurement uncertainty, method development and validation should be performed. Furthermore, a-spectrometry has a major disadvantage of a long counting time, while it has a prominent measurement capability at a very low activity level of {sup 238}U, {sup 235}U, {sup 232}Th, and {sup 226}Ra. Contrary to the α-spectrometry method, a measurement technique using ICP-MS allow radioactivity in many samples to be measured in a short time period with a high degree of accuracy and precision. In this study, a method was developed for a rapid analysis of natural radioactive nuclides using ICP-MS. A sample digestion process was established using LiBO{sub 2} fusion and Fe co-precipitation. A magnetic

  12. Precision mass measurements for studies of nucleosynthesis via the rapid neutron-capture process Penning-trap mass measurements of neutron-rich cadmium and caesium isotopes

    CERN Document Server

    AUTHOR|(CDS)2085660; Litvinov, Yuri A.; Kreim, Susanne

    Although the theory for the rapid neutron-capture process (r-process) was developed more than 55 years ago, the astrophysical site is still under a debate. Theoretical studies predict that the r-process path proceeds through very neutron-rich nuclei with very asymmetric proton- to-neutron ratios. Knowledge about the properties of neutron-rich isotopes found in similar regions of the nuclear chart and furthermore suitable for r-process studies is still little or even not existing. The basic nuclear properties such as binding energies, half-lives, neutron-induced or neutron-capture reaction cross-sections, play an important role in theoretical simulations and can vary or even drastically alternate results of these studies. Therefore, a considerable effort was put forward to access neutron-rich isotopes at radioactive ion-beam facilities like ISOLDE at CERN. The goal of this PhD thesis is to describe the experimental work done for the precision mass measurements of neutron-rich cadmium (129−131 Cd) and caesium...

  13. Rapid detection of porins by matrix-assisted laser desorption/ionization-time of flight mass spectrometry

    Directory of Open Access Journals (Sweden)

    Yanyan eHU

    2015-08-01

    Full Text Available The rapid and cost-efficient determination of carbapenem resistance is an important prerequisite for the choice of an adequate antibiotic therapy. A MALDI-TOF MS-based assay was set up to detect porins in the current study. A loss of the components of porin alone such as OmpK35/OmpK36 or together with the production of carbapenemases will augment the carbapenem resistance. Ten strains of E. coli and eight strains of K. pneumoniae were conducted for both SDS-PAGE and MALDI-TOF MS analysis. MALDI-TOF/TOF MS analysis was then performed to verify the corrospondence of proteins between SDS-PAGE and MALDI-TOF MS. The results indicated that the mass spectrum of ca. 35,000-m/z, 37,000-m/z and 38,000-m/z peaks of E. coli ATCC 25922 corresponded to OmpA, OmpC and OmpF with molecular weight of approximately ca. 38 kDa, 40 kDa and 41 kDa in SDS-PAGE gel, respectively. The band of OmpC and OmpF porins were unable to be distinguished by SDS-PAGE, whereas it was easy to be differentiated by MALDI-TOF MS. As for K. pneumoniae isolates, the mass spectrum of ca. 36,000-m/z and 38,600-m/z peaks was observed corresponding to OmpA and OmpK36 with molecular weight of approximately ca. 40 kDa and 42 kDa in SDS-PAGE gel, respectively. Porin OmpK35 was not observed in the current SDS-PAGE, while a 37,000-m/z peak was found in K. pneumoniae ATCC 13883 and carbapenem-susceptible strains by MALDI-TOF MS which was presumed to be the characteristic peak of the OmpK35 porin. Compared with SDS-PAGE, MALDI-TOF MS is able to rapidly identify the porin-deficient strains within half an hour with better sensitivity, less cost, and is easier to operate and has less interference.

  14. Plasmonic Thermal Decomposition/Digestion of Proteins: A Rapid On-Surface Protein Digestion Technique for Mass Spectrometry Imaging.

    Science.gov (United States)

    Zhou, Rong; Basile, Franco

    2017-09-05

    A method based on plasmon surface resonance absorption and heating was developed to perform a rapid on-surface protein thermal decomposition and digestion suitable for imaging mass spectrometry (MS) and/or profiling. This photothermal process or plasmonic thermal decomposition/digestion (plasmonic-TDD) method incorporates a continuous wave (CW) laser excitation and gold nanoparticles (Au-NPs) to induce known thermal decomposition reactions that cleave peptides and proteins specifically at the C-terminus of aspartic acid and at the N-terminus of cysteine. These thermal decomposition reactions are induced by heating a solid protein sample to temperatures between 200 and 270 °C for a short period of time (10-50 s per 200 μm segment) and are reagentless and solventless, and thus are devoid of sample product delocalization. In the plasmonic-TDD setup the sample is coated with Au-NPs and irradiated with 532 nm laser radiation to induce thermoplasmonic heating and bring about site-specific thermal decomposition on solid peptide/protein samples. In this manner the Au-NPs act as nanoheaters that result in a highly localized thermal decomposition and digestion of the protein sample that is independent of the absorption properties of the protein, making the method universally applicable to all types of proteinaceous samples (e.g., tissues or protein arrays). Several experimental variables were optimized to maximize product yield, and they include heating time, laser intensity, size of Au-NPs, and surface coverage of Au-NPs. Using optimized parameters, proof-of-principle experiments confirmed the ability of the plasmonic-TDD method to induce both C-cleavage and D-cleavage on several peptide standards and the protein lysozyme by detecting their thermal decomposition products with matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). The high spatial specificity of the plasmonic-TDD method was demonstrated by using a mask to digest designated sections of

  15. Rapid Identification of the Foodborne Pathogen Trichinella spp. by Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry.

    Science.gov (United States)

    Mayer-Scholl, Anne; Murugaiyan, Jayaseelan; Neumann, Jennifer; Bahn, Peter; Reckinger, Sabine; Nöckler, Karsten

    2016-01-01

    Human trichinellosis occurs through consumption of raw or inadequately processed meat or meat products containing larvae of the parasitic nematodes of the genus Trichinella. Currently, nine species and three genotypes are recognized, of which T. spiralis, T. britovi and T. pseudospiralis have the highest public health relevance. To date, the differentiation of the larvae to the species and genotype level is based primarily on molecular methods, which can be relatively time consuming and labor intensive. Due to its rapidness and ease of use a matrix assisted laser desorption / ionization time of flight mass spectrometry (MALDI-TOF MS) reference spectra database using Trichinella strains of all known species and genotypes was created. A formicacid/acetonitrile protein extraction was carried out after pooling 10 larvae of each Trichinella species and genotype. Each sample was spotted 9 times using α-cyano 4-hydoxy cinnamic acid matrix and a MicroFlex LT mass spectrometer was used to acquire 3 spectra (m/z 2000 to 20000 Da) from each spot resulting in 27 spectra/species or genotype. Following the spectra quality assessment, Biotyper software was used to create a main spectra library (MSP) representing nine species and three genotypes of Trichinella. The evaluation of the spectra generated by MALDI-TOF MS revealed a classification which was comparable to the results obtained by molecular methods. Also, each Trichinella species utilized in this study was distinct and distinguishable with a high confidence level. Further, different conservation methods such as freezing and conservation in alcohol and the host species origin of the isolated larvae did not have a significant influence on the generated spectra. Therefore, the described MALDI-TOF MS can successfully be implemented for both genus and species level identification and represents a major step forward in the use of this technique in foodborne parasitology.

  16. Rapid dereplication of estrogenic compounds in pomegranate (Punica granatum) using on-line biochemical detection coupled to mass spectrometry.

    Science.gov (United States)

    van Elswijk, Danny A; Schobel, Uwe P; Lansky, Ephraim P; Irth, Hubertus; van der Greef, Jan

    2004-01-01

    During recent years, phytoestrogens have been receiving an increasing amount of interest, as several lines of evidence suggest a possible role in preventing a range of diseases, including the hormonally dependent cancers. In this context, various parts of the pomegranate fruit (Punica granatum; Punicaceae), e.g. seed oil, juice, fermented juice and peel extract, have been shown to exert suppressive effects on human breast cancer cells in vitro. On-line biochemical detection coupled to mass spectrometry (LC-BCD-MS) was applied to rapidly profile the estrogenic activity in the pomegranate peel extract. The crude mixture was separated by HPLC, after which the presence of biologically active compounds, known or unknown, was detected by means of an on-line beta-estrogen receptor (ER) bioassay. Chemical information, such as molecular weight and MS/MS fingerprint, was obtained in real time by directing part of the HPLC effluent towards a mass spectrometer. Using this approach in total three estrogenic compounds, i.e. luteolin, quercetin and kaempferol, were detected and identified by comparing the obtained molecular weights and negative ion APCI MS/MS spectra with the data of an estrogenic compound library. Although well known in literature and widely distributed in nature, the presence of these phytoestrogenic compounds in pomegranate peel extract was not reported previously. Compared to traditional screening approaches of complex mixtures, often characterized by a repeating cycle of HPLC fractionation and biological screening, LC-BCD-MS was shown to profoundly accelerate the time required for compound description and identification.

  17. BREATHING FIRE: HOW STELLAR FEEDBACK DRIVES RADIAL MIGRATION, RAPID SIZE FLUCTUATIONS, AND POPULATION GRADIENTS IN LOW-MASS GALAXIES

    Energy Technology Data Exchange (ETDEWEB)

    El-Badry, Kareem; Geha, Marla [Department of Astronomy, Yale University, New Haven, CT (United States); Wetzel, Andrew; Hopkins, Philip F. [TAPIR, California Institute of Technology, Pasadena, CA USA (United States); Kereš, Dusan; Chan, T. K. [Department of Physics, Center for Astrophysics and Space Sciences, University of California at San Diego, La Jolla (United States); Faucher-Giguère, Claude-André, E-mail: kareem.el-badry@yale.edu [Department of Physics and Astronomy and CIERA, Northwestern University, Evanston, IL (United States)

    2016-04-01

    We examine the effects of stellar feedback and bursty star formation on low-mass galaxies (M{sub star} = 2 × 10{sup 6} − 5 × 10{sup 10} M{sub ⊙}) using the Feedback in Realistic Environments (FIRE) simulations. While previous studies emphasized the impact of feedback on dark matter profiles, we investigate the impact on the stellar component: kinematics, radial migration, size evolution, and population gradients. Feedback-driven outflows/inflows drive significant radial stellar migration over both short and long timescales via two processes: (1) outflowing/infalling gas can remain star-forming, producing young stars that migrate ∼1 kpc within their first 100 Myr, and (2) gas outflows/inflows drive strong fluctuations in the global potential, transferring energy to all stars. These processes produce several dramatic effects. First, galaxies’ effective radii can fluctuate by factors of >2 over ∼200 Myr, and these rapid size fluctuations can account for much of the observed scatter in the radius at fixed M{sub star}. Second, the cumulative effects of many outflow/infall episodes steadily heat stellar orbits, causing old stars to migrate outward most strongly. This age-dependent radial migration mixes—and even inverts—intrinsic age and metallicity gradients. Thus, the galactic-archaeology approach of calculating radial star formation histories from stellar populations at z = 0 can be severely biased. These effects are strongest at M{sub star} ≈ 10{sup 7–9.6} M{sub ⊙}, the same regime where feedback most efficiently cores galaxies. Thus, detailed measurements of stellar kinematics in low-mass galaxies can strongly constrain feedback models and test baryonic solutions to small-scale problems in ΛCDM.

  18. Rapid Identification of the Foodborne Pathogen Trichinella spp. by Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry.

    Directory of Open Access Journals (Sweden)

    Anne Mayer-Scholl

    Full Text Available Human trichinellosis occurs through consumption of raw or inadequately processed meat or meat products containing larvae of the parasitic nematodes of the genus Trichinella. Currently, nine species and three genotypes are recognized, of which T. spiralis, T. britovi and T. pseudospiralis have the highest public health relevance. To date, the differentiation of the larvae to the species and genotype level is based primarily on molecular methods, which can be relatively time consuming and labor intensive. Due to its rapidness and ease of use a matrix assisted laser desorption / ionization time of flight mass spectrometry (MALDI-TOF MS reference spectra database using Trichinella strains of all known species and genotypes was created. A formicacid/acetonitrile protein extraction was carried out after pooling 10 larvae of each Trichinella species and genotype. Each sample was spotted 9 times using α-cyano 4-hydoxy cinnamic acid matrix and a MicroFlex LT mass spectrometer was used to acquire 3 spectra (m/z 2000 to 20000 Da from each spot resulting in 27 spectra/species or genotype. Following the spectra quality assessment, Biotyper software was used to create a main spectra library (MSP representing nine species and three genotypes of Trichinella. The evaluation of the spectra generated by MALDI-TOF MS revealed a classification which was comparable to the results obtained by molecular methods. Also, each Trichinella species utilized in this study was distinct and distinguishable with a high confidence level. Further, different conservation methods such as freezing and conservation in alcohol and the host species origin of the isolated larvae did not have a significant influence on the generated spectra. Therefore, the described MALDI-TOF MS can successfully be implemented for both genus and species level identification and represents a major step forward in the use of this technique in foodborne parasitology.

  19. Potential of fermentation profiling via rapid measurement of amino acid metabolism by liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Dalluge, Joseph J; Smith, Sean; Sanchez-Riera, Fernando; McGuire, Chris; Hobson, Russell

    2004-07-16

    Monitoring amino acid metabolism during fermentation has significant potential from the standpoint of strain selection, optimizing growth and production in host strains, and profiling microbial metabolism and growth state. A method has been developed based on rapid quantification of underivatized amino acids using liquid chromatography-electrospray tandem mass spectrometry (LC-MS-MS) to monitor the metabolism of 20 amino acids during microbial fermentation. The use of a teicoplanin-based chiral stationary phase coupled with electrospray tandem mass spectrometry allows complete amino acid analyses in less than 4 min. Quantification is accomplished using five isotopically labeled amino acids as internal standards. Because comprehensive chromatographic separation and derivatization are not required, analysis time is significantly less than traditional reversed- or normal-phase LC-based amino acid assays. Intra-sample precisions for amino acid measurements in fermentation supernatants using this method average 4.9% (R.S.D.). Inter-day (inter-fermentation) precisions for individual amino acid measurements range from 4.2 to 129% (R.S.D.). Calibration curves are linear over the range 0-300 microg/ml, and detection limits are estimated at 50-450 ng/ml. Data visualization techniques for constructing semi-quantitative fermentation profiles of nitrogen source utilization have also been developed and implemented, and demonstrate that amino acid profiles generally correlate with observed growth profiles. Further, cellular growth events, such as lag-time and cell lysis can be detected using this methodology. Correlation coefficients for the time profiles of each amino acid measured illustrate that while several amino acids are differentially metabolized in similar fermentations, a select group of amino acids display strong correlations in these samples, indicating a sub-population of analytes that may be most useful for fermentation profiling.

  20. Rhesus monkeys (Macaca mulatta) rapidly learn to select dominant individuals in videos of artificial social interactions between unfamiliar conspecifics.

    Science.gov (United States)

    Paxton, Regina; Basile, Benjamin M; Adachi, Ikuma; Suzuki, Wendy A; Wilson, Mark E; Hampton, Robert R

    2010-11-01

    Social animals, such as primates, must behave appropriately in complex social situations such as dominance interactions. Learning dominance information through trial and error would be dangerous; therefore, cognitive mechanisms for rapid learning of dominance information by observation would be adaptive. We used a set of digitally edited artificial social interactions to examine whether rhesus monkeys (Macaca mulatta) can learn dominance relationships between unfamiliar conspecifics through observation. Our method allowed random assignment of stimulus monkeys to ranks in an artificial hierarchy, controlling for nonbehavioral cues that could indicate dominance. Subject monkeys watched videos depicting 1 stimulus monkey behaving dominantly toward another and were rewarded for selecting the dominant individual. Monkeys rapidly learned this discrimination across 5 behavior types in Experiment 1 and transferred performance to novel videos of new individuals in Experiment 2. In addition, subjects selected the dominant individual more often than expected by chance in probe videos containing no behavioral dominance information, indicating some retention of the relative dominance status of stimulus monkeys from training. Together, our results suggest that monkeys can learn dominance hierarchies through observation of third-party social interactions. (PsycINFO Database Record (c) 2010 APA, all rights reserved).

  1. Estimating the mass of the Local Group using machine learning applied to numerical simulations

    Science.gov (United States)

    McLeod, M.; Libeskind, N.; Lahav, O.; Hoffman, Y.

    2017-12-01

    We present a new approach to calculating the combined mass of the Milky Way (MW) and Andromeda (M31), which together account for the bulk of the mass of the Local Group (LG). We base our work on an ensemble of 30,190 halo pairs from the Small MultiDark simulation, assuming a ΛCDM (Cosmological Constant and Cold Dark Matter) cosmology. This is used in conjunction with machine learning methods (artificial neural networks, ANN) to investigate the relationship between the mass and selected parameters characterising the orbit and local environment of the binary. ANN are employed to take account of additional physics arising from interactions with larger structures or dynamical effects which are not analytically well understood. Results from the ANN are most successful when the velocity shear is provided, which demonstrates the flexibility of machine learning to model physical phenomena and readily incorporate new information. The resulting estimate for the Local Group mass, when shear information is included, is 4.9×1012Msolar, with an error of ±0.8×1012Msolar from the 68% uncertainty in observables, and a r.m.s. scatter interval of +1.7‑1.3×1012Msolar estimated scatter from the differences between the model estimates and simulation masses for a testing sample of halo pairs. We also consider a recently reported large relative transverse velocity of M31 and the Milky Way, and produce an alternative mass estimate of 3.6±0.3+2.1‑1.3×1012Msolar. Although the methods used predict similar values for the most likely mass of the LG, application of ANN compared to the traditional Timing Argument reduces the scatter in the log mass by approximately half when tested on samples from the simulation.

  2. Rapid identification of Mycobacterium avium clinical isolates by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

    Science.gov (United States)

    Lin, Chuan-Sheng; Su, Chih-Cheng; Hsieh, Shang-Chen; Lu, Chia-Chen; Wu, Tsu-Lan; Jia, Ju-Hsin; Wu, Ting-Shu; Han, Chau-Chung; Tsai, Wen-Cherng; Lu, Jang-Jih; Lai, Hsin-Chih

    2015-04-01

    Rapid and accurate discrimination of Mycobacterium avium from other mycobacteria is essential for appropriate therapeutic management and timely intervention for infection control. However, routine clinical identification methods for M. avium are both time consuming and labor intensive. In the present study, matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) was used to identify specific cellular protein pattern for rapid identification of M. avium isolates. A total of 40 clinically relevant Mycobacterium strains comprising 13 distinct species were enrolled for the MALDI-TOF MS identification. A 10-minute extraction-free examination procedure was set up to obtain mass spectral fingerprints from whole bacterial cells. The characteristic mass spectral peak patterns in the m/z (mass/charge ratio) range of 5-20 kDa can be obtained within 10 minutes. The species-specific mass spectra for M. avium is identified and can be differentiated from as Mycobacterium strains. This technique shortens and simplifies the identification procedure of MALDI-TOF MS and may further extend the mycobacterial MALDI-TOF MS database. Simplicity and rapidity of identification procedures make MALDI-TOF MS an attractive platform in routine identification of mycobacteria. MALDI-TOF MS is applicable for rapid discrimination of M. avium from other Mycobacterium species, and shows its potential for clinical application. Copyright © 2013. Published by Elsevier B.V.

  3. Rapid Production of E-Learning Materials with Reusable Learning Objects: Experiences from the Global Academy for Extension Practice

    Directory of Open Access Journals (Sweden)

    Mary Holz-Clause

    2012-08-01

    Full Text Available Open educational resources, institutional collaborations, and content reusability approaches have been quickly emerging to minimize the time and money spent on developing e-learning materials. Reusing content with reusable learning objects (RLOs is carving a new path for research on reusing and repurposing available high quality e-learning content. Prior research shows that this component-based approach best fits how educators prefer to access materials. In this paper, without arguing the merits and demerits of RLOs as a concept, the authors present an effective and affordable approach to creating e-learning materials with RLOs. The authors also present how they have implemented the proposed RLO approach in converting learning modules of the Global Academy for Extension Practice into multiple e-learning material formats.

  4. Establishment of an Efficient In Vitro Regeneration Protocol for Rapid and Mass Propagation of Dendrobium chrysotoxum Lindl. Using Seed Culture

    Science.gov (United States)

    2014-01-01

    An efficient in vitro regeneration protocol from seed culture has been established successfully for Dendrobium chrysotoxum, an epiphytic orchid having tremendous ornamental and medicinal values. Seed germination response was encouraging in Mitra (M) medium enriched with different combinations of auxins and cytokinins. Medium supplemented with 0.4% activated charcoal (AC), 2 mg/L 6-benzyl amino purine (BAP), and 2 mg/L indole-3-acetic acid (IAA) produced best seed germination percentage in 2 weeks of culture. Incorporation of higher concentration of kinetin (KN) or BAP in combination with low auxin in medium induced pronounced shooting and leaf formation. Reduction in leaf development was evident when cytokinins exist singly in medium indicating synergistic effect of auxin and cytokinin in leaf induction. Presence of elevated level of indole-3-butyric acid (IBA) or 1-naphthalene acetic acid (NAA) with low cytokinin content in medium generated more in vitro rooting, though IBA was found to be more effective in rooting induction as compared to NAA. The in vitro protocol for asymbiotic seed germination developed from the present investigation can be used for rapid mass propagation of this highly important Dendrobium orchid species. PMID:25401154

  5. Rapid Determination of L-carnitine in Infant and Toddler Formulas by Liquid Chromatography Tandem Mass Spectrometry.

    Science.gov (United States)

    Ahn, Jang-Hyuk; Kwak, Byung-Man; Park, Jung-Min; Kim, Na-Kyeoung; Kim, Jin-Man

    2014-01-01

    A rapid and simple analytical method for L-carnitine was developed for infant and toddler formulas by liquid chromatography tandem mass spectrometry (LC-MS/MS). A 0.3 g of infant formula and toddler formula sample was mixed in a 50 mL conical tube with 9 mL water and 1 mL 0.1 M hydrochloric acid (HCl) to chemical extraction. Then, chloroform was used for removing a lipid fraction. After centrifuged, L-carnitine was separated and quantified using LC-MS/MS with electrospray ionization (ESI) mode. The precursor ion for L-carnitine was m/z 162, and product ions were m/z 103 (quantitative) and m/z 85 (qualitative), respectively. The results for spiked recovery test were in the range of 93.18-95.64% and the result for certified reference material (SRM 1849a) was within the range of the certificated values. This method could be implemented in many laboratories that require time and labor saving.

  6. Establishment of an efficient in vitro regeneration protocol for rapid and mass propagation of Dendrobium chrysotoxum Lindl. using seed culture.

    Science.gov (United States)

    Nongdam, Potshangbam; Tikendra, Leimapokpam

    2014-01-01

    An efficient in vitro regeneration protocol from seed culture has been established successfully for Dendrobium chrysotoxum, an epiphytic orchid having tremendous ornamental and medicinal values. Seed germination response was encouraging in Mitra (M) medium enriched with different combinations of auxins and cytokinins. Medium supplemented with 0.4% activated charcoal (AC), 2 mg/L 6-benzyl amino purine (BAP), and 2 mg/L indole-3-acetic acid (IAA) produced best seed germination percentage in 2 weeks of culture. Incorporation of higher concentration of kinetin (KN) or BAP in combination with low auxin in medium induced pronounced shooting and leaf formation. Reduction in leaf development was evident when cytokinins exist singly in medium indicating synergistic effect of auxin and cytokinin in leaf induction. Presence of elevated level of indole-3-butyric acid (IBA) or 1-naphthalene acetic acid (NAA) with low cytokinin content in medium generated more in vitro rooting, though IBA was found to be more effective in rooting induction as compared to NAA. The in vitro protocol for asymbiotic seed germination developed from the present investigation can be used for rapid mass propagation of this highly important Dendrobium orchid species.

  7. Rapid and reliable MALDI-TOF mass spectrometry identification of Candida non-albicans isolates from bloodstream infections.

    Science.gov (United States)

    Pulcrano, Giovanna; Iula, Dora Vita; Vollaro, Antonio; Tucci, Alessandra; Cerullo, Monica; Esposito, Matilde; Rossano, Fabio; Catania, Maria Rosaria

    2013-09-01

    Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry (MS) fingerprinting has recently become an effective instrument for rapid microbiological diagnostics and in particular for identification of micro-organisms directly in a positive blood culture. The aim of the study was to evaluate a collection of 82 stored yeast isolates from bloodstream infection, by MALDI-TOF MS; 21 isolates were identified also directly from positive blood cultures and in the presence of other co-infecting micro-organisms. Of the 82 isolates grown on plates, 64 (76%) were correctly identified by the Vitek II system and 82 (100%) by MALDI-TOF MS; when the two methods gave different results, the isolate was identified by PCR. MALDI-TOF MS was unreliable in identifying two isolates (Candida glabrata and Candida parapsilosis) directly from blood culture; however, direct analysis from positive blood culture samples was fast and effective for the identification of yeast, which is of great importance for early and adequate treatment. © 2013. Published by Elsevier B.V. All rights reserved.

  8. Infrastructure and distributed learning methodology for privacy-preserving multi-centric rapid learning health care: euroCAT

    Directory of Open Access Journals (Sweden)

    Timo M. Deist

    2017-06-01

    The euroCAT infrastructure has been successfully implemented in five radiation clinics across three countries. SVM models can be learned on data distributed over all five clinics. Furthermore, the infrastructure provides a general framework to execute learning algorithms on distributed data. The ongoing expansion of the euroCAT network will facilitate machine learning in radiation oncology. The resulting access to larger datasets with sufficient variation will pave the way for generalizable prediction models and personalized medicine.

  9. Relationships between rapid isometric torque characteristics and vertical jump performance in division I collegiate American football players: influence of body mass normalization.

    Science.gov (United States)

    Thompson, Brennan J; Ryan, Eric D; Sobolewski, Eric J; Smith, Doug B; Akehi, Kazuma; Conchola, Eric C; Buckminster, Tyler

    2013-10-01

    The purpose of the present study was to examine the relationships between absolute and body mass-normalized rapid isometric torque variables and vertical jump (VJ) performance of the leg extensors and flexors in elite National Collegiate Athletic Association Division I Football Bowl Subdivision collegiate American football players. Thirty-one players performed isometric maximal voluntary contractions of the leg extensor and flexor muscle groups and a countermovement VJ. Rate of torque development (RTD) and the contractile impulse (IMPULSE) were determined from 0 to 30, 0 to 50, 0 to 100, and 0 to 200 milliseconds from the onset of muscular contraction. The relationships between absolute and normalized rapid torque variables and VJ performance were assessed using correlation coefficients (r). There were no significant correlations (p > 0.05) observed between the absolute rapid torque variables and VJ performance, except for leg flexion RTD at 0-200 milliseconds (p = 0.024). All normalized rapid torque variables of the leg extensors and flexors were significantly correlated to VJ performance (p ≤ 0.001-0.026). These findings indicated that normalizing rapid torque variables to body mass improves the relationships between isometric rapid torque variables and VJ performance and normalized leg extension and flexion are both similarly related to VJ performance. Strength and conditioning professionals may use these findings in an attempt to identify and monitor dynamic sport performance. Furthermore, future studies examining the relationship between dynamic on the field performances and laboratory-based isometric strength testing may consider including normalized rapid torque variables.

  10. Computer-aided classification of mammographic masses using the deep learning technology: a preliminary study

    Science.gov (United States)

    Qiu, Yuchen; Yan, Shiju; Tan, Maxine; Cheng, Samuel; Liu, Hong; Zheng, Bin

    2016-03-01

    Although mammography is the only clinically acceptable imaging modality used in the population-based breast cancer screening, its efficacy is quite controversy. One of the major challenges is how to help radiologists more accurately classify between benign and malignant lesions. The purpose of this study is to investigate a new mammographic mass classification scheme based on a deep learning method. In this study, we used an image dataset involving 560 regions of interest (ROIs) extracted from digital mammograms, which includes 280 malignant and 280 benign mass ROIs, respectively. An eight layer deep learning network was applied, which employs three pairs of convolution-max-pooling layers for automatic feature extraction and a multiple layer perception (MLP) classifier for feature categorization. In order to improve robustness of selected features, each convolution layer is connected with a max-pooling layer. A number of 20, 10, and 5 feature maps were utilized for the 1st, 2nd and 3rd convolution layer, respectively. The convolution networks are followed by a MLP classifier, which generates a classification score to predict likelihood of a ROI depicting a malignant mass. Among 560 ROIs, 420 ROIs were used as a training dataset and the remaining 140 ROIs were used as a validation dataset. The result shows that the new deep learning based classifier yielded an area under the receiver operation characteristic curve (AUC) of 0.810+/-0.036. This study demonstrated the potential superiority of using a deep learning based classifier to distinguish malignant and benign breast masses without segmenting the lesions and extracting the pre-defined image features.

  11. Dynamic changes in single unit activity and γ oscillations in a thalamocortical circuit during rapid instrumental learning.

    Directory of Open Access Journals (Sweden)

    Chunxiu Yu

    Full Text Available The medial prefrontal cortex (mPFC and mediodorsal thalamus (MD together form a thalamocortical circuit that has been implicated in the learning and production of goal-directed actions. In this study we measured neural activity in both regions simultaneously, as rats learned to press a lever to earn food rewards. In both MD and mPFC, instrumental learning was accompanied by dramatic changes in the firing patterns of the neurons, in particular the rapid emergence of single-unit neural activity reflecting the completion of the action and reward delivery. In addition, we observed distinct patterns of changes in the oscillatory LFP response in MD and mPFC. With learning, there was a significant increase in theta band oscillations (6-10 Hz in the MD, but not in the mPFC. By contrast, gamma band oscillations (40-55 Hz increased in the mPFC, but not in the MD. Coherence between these two regions also changed with learning: gamma coherence in relation to reward delivery increased, whereas theta coherence did not. Together these results suggest that, as rats learned the instrumental contingency between action and outcome, the emergence of task related neural activity is accompanied by enhanced functional interaction between MD and mPFC in response to the reward feedback.

  12. Rapid analysis of pharmaceuticals and personal care products in fish plasma micro-aliquots using liquid chromatography tandem mass spectrometry.

    Science.gov (United States)

    Chen, Fangfang; Gong, Zhiyuan; Kelly, Barry C

    2015-02-27

    A sensitive analytical method based on liquid-liquid extraction (LLE) and liquid chromatography tandem mass spectrometry (LC-MS/MS) was developed for rapid analysis of 11 pharmaceuticals and personal care products (PPCPs) in fish plasma micro-aliquots (∼20μL). Target PPCPs included, bisphenol A, carbamazepine, diclofenac, fluoxetine, gemfibrozil, ibuprofen, naproxen, risperidone, sertraline, simvastatin and triclosan. A relatively quicker and cheaper LLE procedure exhibited comparable analyte recoveries with solid-phase extraction. Rapid separation and analysis of target compounds in fish plasma extracts was achieved by employing a high efficiency C-18 HPLC column (Agilent Poroshell 120 SB-C18, 2.1mm×50mm, 2.7μm) and fast polarity switching, enabling effective monitoring of positive and negative ions in a single 9min run. With the exception of bisphenol A, which exhibited relatively high background contamination, method detection limits of individual PPCPs ranged between 0.15 and 0.69pg/μL, while method quantification limits were between 0.05 and 2.3pg/μL. Mean matrix effect (ME) values ranged between 65 and 156% for the various target analytes. Isotope dilution quantification using isotopically labelled internal surrogates was utilized to correct for signal suppression or enhancement and analyte losses during sample preparation. The method was evaluated by analysis of 20μL plasma micro-aliquots collected from zebrafish (Danio rerio) from a laboratory bioaccumulation study, which included control group fish (no exposure), as well as fish exposed to environmentally relevant concentrations of PPCPs. Using the developed LC-MS/MS based method, concentrations of the studied PPCPs were consistently detected in the low pg/μL (ppb) range. The method may be useful for investigations requiring fast, reliable concentration measurements of PPCPs in fish plasma. In particular, the method may be applicable for in situ contaminant biomonitoring, as well as

  13. Rapid screening of N-oxides of chemical warfare agents degradation products by ESI-tandem mass spectrometry.

    Science.gov (United States)

    Sridhar, L; Karthikraj, R; Lakshmi, V V S; Raju, N Prasada; Prabhakar, S

    2014-08-01

    Rapid detection and identification of chemical warfare agents and related precursors/degradation products in various environmental matrices is of paramount importance for verification of standards set by the chemical weapons convention (CWC). Nitrogen mustards, N,N-dialkylaminoethyl-2-chlorides, N,N-dialkylaminoethanols, N-alkyldiethanolamines, and triethanolamine, which are listed CWC scheduled chemicals, are prone to undergo N-oxidation in environmental matrices or during decontamination process. Thus, screening of the oxidized products of these compounds is also an important task in the verification process because the presence of these products reveals alleged use of nitrogen mustards or precursors of VX compounds. The N-oxides of aminoethanols and aminoethylchlorides easily produce [M + H](+) ions under electrospray ionization conditions, and their collision-induced dissociation spectra include a specific neutral loss of 48 u (OH + CH2OH) and 66 u (OH + CH2Cl), respectively. Based on this specific fragmentation, a rapid screening method was developed for screening of the N-oxides by applying neutral loss scan technique. The method was validated and the applicability of the method was demonstrated by analyzing positive and negative samples. The method was useful in the detection of N-oxides of aminoethanols and aminoethylchlorides in environmental matrices at trace levels (LOD, up to 500 ppb), even in the presence of complex masking agents, without the use of time-consuming sample preparation methods and chromatographic steps. This method is advantageous for the off-site verification program and also for participation in official proficiency tests conducted by the Organization for the Prohibition of Chemical Weapons (OPCW), the Netherlands. The structure of N-oxides can be confirmed by the MS/MS experiments on the detected peaks. A liquid chromatography-mass spectrometry (LC-MS) method was developed for the separation of isomeric N-oxides of aminoethanols and

  14. Multilevel learning-based segmentation of ill-defined and spiculated masses in mammograms

    Energy Technology Data Exchange (ETDEWEB)

    Tao, Yimo; Lo, Shih-Chung B.; Freedman, Matthew T.; Makariou, Erini; Xuan, Jianhua [Department of Electrical and Computer Engineering, Virginia Polytechnic Institute and State University, Arlington, Virginia 22203 (United States) and Department of Radiology, ISIS Center, Georgetown University Medical Center, Washington, DC 20007 (United States); Department of Radiology, ISIS Center, Georgetown University Medical Center, Washington, DC 20007 (United States); Department of Oncology, Georgetown University Medical Center, Washington, DC 20007 (United States); Department of Radiology, Georgetown University Medical Center, Washington, DC 20007 (United States); Department of Electrical and Computer Engineering, Virginia Polytechnic Institute and State University, Arlington, Virginia 22203 (United States)

    2010-11-15

    Purpose: A learning-based approach integrating the use of pixel-level statistical modeling and spiculation detection is presented for the segmentation of mammographic masses with ill-defined margins and spiculations. Methods: The algorithm involves a multiphase pixel-level classification, using a comprehensive group of features computed from regional intensity, shape, and textures, to generate a mass-conditional probability map (PM). Then, the mass candidate, along with the background clutters consisting of breast fibroglandular and other nonmass tissues, is extracted from the PM by integrating the prior knowledge of shape and location of masses. A multiscale steerable ridge detection algorithm is employed to detect spiculations. Finally, all the object-level findings, including mass candidate, detected spiculations, and clutters, along with the PM, are integrated by graph cuts to generate the final segmentation mask. Results: The method was tested on 54 masses (51 malignant and 3 benign), all with ill-defined margins and irregular shape or spiculations. The ground truth delineations were provided by five experienced radiologists. Area overlapping ratio of 0.689 ({+-}0.160) and 0.540 ({+-}0.164) were obtained for segmenting entire mass and margin portion only, respectively. Williams index of area and contour based measurements indicated that the segmentation results of the algorithm agreed well with the radiologists' delineation. Conclusions: The proposed approach could closely delineate the mass body. Most importantly, it is capable of including mass margin and its spicule extensions which are considered as key features for breast lesion analyses.

  15. A digital microfluidic system for the investigation of pre-steady-state enzyme kinetics using rapid quenching with MALDI-TOF mass spectrometry

    NARCIS (Netherlands)

    Nichols, K.P.F.; Gardeniers, Johannes G.E.

    2007-01-01

    A digital microfluidic system based on electrowetting has been developed to facilitate the investigation of pre-steady-state reaction kinetics using rapid quenching and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The device consists of individually

  16. Proton Transfer Reaction Mass Spectrometry detects rapid changes in volatile metabolite emission by Mycobacterium smegmatis after the addition of specific antimicrobial agents

    NARCIS (Netherlands)

    Crespo, E.; Cristescu, S. M.; de Ronde, H.; Kuijper, S.; Kolk, A.H.J.; Anthony, R.M.; Harren, F. J. M.

    2011-01-01

    The metabolic activity of plants, animals or microbes can be monitored by gas headspace analysis. This can be achieved using Proton Transfer Reaction Mass Spectrometry (PTR-MS), a highly sensitive detection method for trace gas analysis. PTR-MS is rapid and can detect metabolic responses on-line as

  17. What can we learn from atmospheres of transitioning low-mass towards habitable planets?

    Science.gov (United States)

    Ikoma, Masahiro

    2015-07-01

    Transit observations with the Kepler space telescope revealed that planets smaller than Neptune are much more abundant than gas giants beyond our Solar System. The observed mass-radius relationships for such small planets are known to be diverse, which may mean that the amount of the atmospheric gas differs from planet to planet. Also, recent observational characterization of atmospheres of some transiting low-mass exoplanets suggests that the atmospheric composition is also diverse. Thus, understanding the diversity of atmospheres of transiting low-mass planets and their origins must be a key to predicting possible diversity of planets in habitable zones. In this paper, I will overview recent theories of the formation and evolution of planetary atmosphere. I will also discuss what we can learn from on-going and future observations for characterizing transiting planet atmospheres.

  18. Mass detection in digital breast tomosynthesis: Deep convolutional neural network with transfer learning from mammography.

    Science.gov (United States)

    Samala, Ravi K; Chan, Heang-Ping; Hadjiiski, Lubomir; Helvie, Mark A; Wei, Jun; Cha, Kenny

    2016-12-01

    Develop a computer-aided detection (CAD) system for masses in digital breast tomosynthesis (DBT) volume using a deep convolutional neural network (DCNN) with transfer learning from mammograms. A data set containing 2282 digitized film and digital mammograms and 324 DBT volumes were collected with IRB approval. The mass of interest on the images was marked by an experienced breast radiologist as reference standard. The data set was partitioned into a training set (2282 mammograms with 2461 masses and 230 DBT views with 228 masses) and an independent test set (94 DBT views with 89 masses). For DCNN training, the region of interest (ROI) containing the mass (true positive) was extracted from each image. False positive (FP) ROIs were identified at prescreening by their previously developed CAD systems. After data augmentation, a total of 45 072 mammographic ROIs and 37 450 DBT ROIs were obtained. Data normalization and reduction of non-uniformity in the ROIs across heterogeneous data was achieved using a background correction method applied to each ROI. A DCNN with four convolutional layers and three fully connected (FC) layers was first trained on the mammography data. Jittering and dropout techniques were used to reduce overfitting. After training with the mammographic ROIs, all weights in the first three convolutional layers were frozen, and only the last convolution layer and the FC layers were randomly initialized again and trained using the DBT training ROIs. The authors compared the performances of two CAD systems for mass detection in DBT: one used the DCNN-based approach and the other used their previously developed feature-based approach for FP reduction. The prescreening stage was identical in both systems, passing the same set of mass candidates to the FP reduction stage. For the feature-based CAD system, 3D clustering and active contour method was used for segmentation; morphological, gray level, and texture features were extracted and merged with a

  19. Rapid quantification of metabolic intermediates in blood by liquid chromatography-tandem mass spectrometry to investigate congenital lactic acidosis.

    Science.gov (United States)

    Peng, Minzhi; Cai, Yanna; Fang, Xiefan; Liu, Li

    2016-10-26

    A novel liquid chromatography-tandem mass spectrometry (LC-MS/MS) method has been established to quantify metabolic intermediates, including lactate (Lac), pyruvate (Pyr), acetoacetate (ACAC) and 3-hydroxybutyrate (3-HB) in blood. Samples were deproteinized with methanol-acetonitrile solution, and analytes were separated on an adamantyl group-bonded reverse phase column and detected in multiple reaction monitoring mode. Total analysis time was 4 min per sample. Method validation results displayed that limits of quantification were 10.0 μmol L(-1) for Lac and Pyr, and 5.0 μmol L(-1)for ACAC and 3-HB. The within- and between-run coefficients of variation were in the range of 1.2-6.4% for all analytes. The recoveries were ranged from 95.6 to 111.5%. The reference values of analytes were determined for the pediatric population. Duo to instability of Lac, Pyr and ACAC in vitro, a comprehensive stability assay was performed to determine optimal conditions for sample collection, pretreatment and storage. Results showed that precipitation of protein in blood at bedside combined with low storage temperature could effectively preserve the integrity of Lac, Pyr and 3-HB, but the precipitated protein accelerated degradation of ACAC. Isolation of supernatant fluid slowed degradation of ACAC. Supernatant samples could store at -20 °C for 10 days. The use of plasma or serum to determine these intermediates was not recommended. In this study, 450 samples from patients were analyzed, and 7 patients were diagnosed as congenital lactic acidosis. With the advantages of rapid, accurate and reliable, this method is very suitable for congenital lactic acidosis screening and researches related to energy metabolism. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Rapid detection and ruling out of neonatal sepsis by PCR coupled with Electrospray Ionization Mass Spectrometry (PCR/ESI-MS).

    Science.gov (United States)

    Delcò, Cristina; Karam, Oliver; Pfister, Riccardo; Gervaix, Alain; Renzi, Gesuele; Emonet, Stéphane; Schrenzel, Jacques; Posfay-Barbe, Klara M

    2017-05-01

    Sepsis is an important cause of morbidity and mortality in neonates and clinicians are typically required to administer empiric antibiotics while waiting for blood culture results. However, prolonged and inappropriate use of antibiotics is associated with various complications and adverse events. Better tools to rapidly rule out bacterial infections are therefore needed. We aimed to assess the negative predictive value of PCR coupled with Electrospray Ionization Mass Spectrometry (PCR/ESI-MS) compared to conventional blood cultures in neonatal sepsis. Prospective observational study. All consecutive neonates (PCR/ESI-MS analysis were collected at the same time as samples for the blood culture, before the initiation of antibiotics. Our primary objective was to evaluate the negative predictive value of PCR/ESI-MS for the detection of bacteria in the bloodstream of newborns with suspected sepsis. Our secondary objective was the evaluation of the sensitivity, specificity and positive predictive value of the PCR/ESI-MS in such a neonatal population. We analysed 114 samples over 14months. The median age and weight were 32weeks+3days and 1840g, respectively. Two patients had negative PCR/ESI-MS results, but positive blood cultures. Overall, the negative predictive value was 98% (95%CI: 92% to 100%). Based on these results, PCR/ESI-MS analysis of blood samples of neonates with suspected sepsis appears to have a very good negative predictive value when compared to blood cultures as gold standard. This novel test might allow for early reassessment of the need for antibiotics. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Rapid methods to determine procyanidins, anthocyanins, theobromine and caffeine in rat tissues by liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Serra, Aida; Macià, Alba; Romero, Maria-Paz; Piñol, Carme; Motilva, Maria-José

    2011-06-01

    Rapid, selective and sensitive methods were developed and validated to determine procyanidins, anthocyanins and alkaloids in different biological tissues, such as liver, brain, the aorta vein and adipose tissue. For this purpose, standards of procyanidins (catechin, epicatechin, and dimer B(2)), anthocyanins (cyanidin-3-glucoside and malvidin-3-glucoside) and alkaloids (theobromine, caffeine and theophylline) were used. The methods included the extraction of homogenized tissues by off-line liquid-solid extraction, and then solid-phase extraction to analyze alkaloids, or microelution solid-phase extraction plate for the analysis of procyanidins and anthocyanins. The eluted extracts were then analyzed by ultra-performance liquid chromatography-electrospray ionization-tandem mass spectrometry, using a triple quadrupole as the analyzer. The optimum extraction solution was water/methanol/phosphoric acid 4% (94/4.5/1.5, v/v/v). The extraction recoveries were higher than 81% for all the studied compounds in all the tissues, except the anthocyanins, which were between 50 and 65% in the liver and brain. In order to show the applicability of the developed methods, different rat tissues were analyzed to determine the procyanidins, anthocyanins and alkaloids and their generated metabolites. The rats had previously consumed 1g of a grape pomace extract (to analyze procyanidins and anthocyanins) or a cocoa extract (to analyze alkaloids) per kilogram of body weight. Different tissues were extracted 4h after administration of the respective extracts. The analysis of the metabolites revealed a hepatic metabolism of procyanidins. The liver was the tissue which produced a greater accumulation of these metabolites. Copyright © 2011 Elsevier B.V. All rights reserved.

  2. Carbachol induces a rapid and sustained hydrolysis of polyphosphoinositide in bovine tracheal smooth muscle measurements of the mass of polyphosphoinositides, 1,2-diacylglycerol, and phosphatidic acid.

    Science.gov (United States)

    Takuwa, Y; Takuwa, N; Rasmussen, H

    1986-11-05

    The effects of carbachol on polyphosphoinositides and 1,2-diacylglycerol metabolism were investigated in bovine tracheal smooth muscle by measuring both lipid mass and the turnover of [3H]inositol-labeled phosphoinositides. Carbachol induces a rapid reduction in the mass of phosphatidylinositol 4,5-bisphosphate and phosphatidylinositol 4-monophosphate and a rapid increase in the mass of 1,2-diacylglycerol and phosphatidic acid. These changes in lipid mass are sustained for at least 60 min. The level of phosphatidylinositol shows a delayed and progressive decrease during a 60-min period of carbachol stimulation. The addition of atropine reverses these responses completely. Carbachol stimulates a rapid loss in [3H]inositol radioactivity from phosphatidylinositol 4,5-bisphosphate and phosphatidylinositol 4-monophosphate associated with production of [3H]inositol trisphosphate. The carbachol-induced change in the mass of phosphoinositides and phosphatidic acid is not affected by removal of extracellular Ca2+ and does not appear to be secondary to an increase in intracellular Ca2+. These results indicate that carbachol causes phospholipase C-mediated polyphosphoinositide breakdown, resulting in the production of inositol trisphosphate and a sustained increase in the actual content of 1,2-diacylglycerol. These results strongly suggest that carbachol-induced contraction is mediated by the hydrolysis of polyphosphoinositides with the resulting generation of two messengers: inositol 1,4,5-trisphosphate and 1,2-diacylglycerol.

  3. Carbachol induces a rapid and sustained hydrolysis of polyphosphoinositide in bovine tracheal smooth muscle measurements of the mass of polyphosphoinositides, 1,2-diacylglycerol, and phosphatidic acid

    Energy Technology Data Exchange (ETDEWEB)

    Takuwa, Y.; Takuwa, N.; Rasmussen, H.

    1986-11-05

    The effects of carbachol on polyphosphoinositides and 1,2-diacylglycerol metabolism were investigated in bovine tracheal smooth muscle by measuring both lipid mass and the turnover of (/sup 3/H)inositol-labeled phosphoinositides. Carbachol induces a rapid reduction in the mass of phosphatidylinositol 4,5-bisphosphate and phosphatidylinositol 4-monophosphate and a rapid increase in the mass of 1,2-diacylglycerol and phosphatidic acid. These changes in lipid mass are sustained for at least 60 min. The level of phosphatidylinositol shows a delayed and progressive decrease during a 60-min period of carbachol stimulation. The addition of atropine reverses these responses completely. Carbachol stimulates a rapid loss in (/sup 3/H)inositol radioactivity from phosphatidylinositol 4,5-bisphosphate and phosphatidylinositol 4-monophosphate associated with production of (/sup 3/H)inositol trisphosphate. The carbachol-induced change in the mass of phosphoinositides and phosphatidic acid is not affected by removal of extracellular Ca/sup 2 +/ and does not appear to be secondary to an increase in intracellular Ca/sup 2 +/. These results indicate that carbachol causes phospholipase C-mediated polyphosphoinositide breakdown, resulting in the production of inositol trisphosphate and a sustained increase in the actual content of 1,2-diacylglycerol. These results strongly suggest that carbachol-induced contraction is mediated by the hydrolysis of polyphosphoinositides with the resulting generation of two messengers: inositol 1,4,5-trisphosphate and 1,2-diacylglycerol.

  4. Rapid language-related plasticity: microstructural changes in the cortex after a short session of new word learning.

    Science.gov (United States)

    Hofstetter, Shir; Friedmann, Naama; Assaf, Yaniv

    2017-04-01

    Human brain imaging revealed that the brain can undergo structural plasticity following new learning experiences. Most magnetic resonance imaging (MRI) uncovered morphometric alternation in cortical density after the long-term training of weeks to months. A recent diffusion tensor imaging (DTI) study has found changes in diffusion indices after 2 h of training, primarily in the hippocampus. However, whether a short learning experience can induce microstructural changes in the neocortex is still unclear. Here, we used diffusion MRI, a method sensitive to tissue microstructure, to study cortical plasticity. To attain cortical involvement, we used a short language task (under 1 h) of introducing new lexical items (flower names) to the lexicon. We have found significant changes in diffusivity in cortical regions involved in language and reading (inferior frontal gyrus, middle temporal gyrus, and inferior parietal lobule). In addition, the difference in the values of diffusivity correlated with the lexical learning rate in the task. Moreover, significant changes were found in white matter tracts near the cortex, and the extent of change correlated with behavioral measures of lexical learning rate. These findings provide first evidence of short-term cortical plasticity in the human brain after a short language learning task. It seems that short training of less than an hour of high cognitive demand can induce microstructural changes in the cortex, suggesting a rapid time scale of neuroplasticity and providing additional evidence of the power of MRI to investigate the temporal and spatial progressions of this process.

  5. A Rapid Review of the Factors Affecting Healthcare Students' Satisfaction with Small-Group, Active Learning Methods.

    Science.gov (United States)

    Kilgour, James M; Grundy, Lisa; Monrouxe, Lynn V

    2016-01-01

    PHENOMENON: Problem-based learning (PBL) and other small-group, active learning methodologies have been widely adopted into undergraduate and postgraduate healthcare curricula across the world. Although much research has examined student perceptions of these innovative teaching pedagogies, there are still questions over which factors influence these views. This article aims to identify these key elements that affect healthcare student satisfaction with PBL and other small-group learning methods, including case-based and team-based learning. A systematic rapid review method was used to identify high-quality original research papers from the healthcare education literature from between 2009 and 2014. All papers were critically appraised before inclusion in line with published guidelines. Narrative synthesis was achieved using an inductively developed, thematic framework approach. Fifty-four papers were included in the narrative synthesis. The evidence suggests that, despite an initial period of negative emotion and anxiety, the perspectives of healthcare students toward small-group, active learning methods are generally positive. The key factors influencing this satisfaction level include (a) the facilitator role, (b) tutorial structure, (c) individual student factors, (d) case authenticity, (e) increased feedback, (f) group harmony, and (g) resource availability. Insights: Student satisfaction is an important determinant of healthcare education quality, and the findings of this review may be of value in future curriculum design. The evidence described here suggests that an ideal curriculum may be based on an expert-led, hybrid PBL model.

  6. Exemplar variability facilitates rapid learning of an otherwise unlearnable grammar by individuals with language-based learning disability.

    Science.gov (United States)

    von Koss Torkildsen, Janne; Dailey, Natalie S; Aguilar, Jessica M; Gómez, Rebecca; Plante, Elena

    2013-04-01

    Even without explicit instruction, learners are able to extract information about the form of a language simply by attending to input that reflects the underlying grammar. In this study, the authors explored the role of variability in this learning by asking whether varying the number of unique exemplars heard by the learner affects learning of an artificial syntactic form. Learners with normal language (n = 16) and language-based learning disability (LLD; n = 16) were exposed to strings of nonwords that represented an underlying grammar. Half of the learners heard 3 exemplars 16 times each (low variability group), and the other half of the learners heard 24 exemplars twice each (high variability group). Learners were then tested for recognition of items heard and generalization of the grammar with new nonword strings. Only those learners with LLD who were in the high variability group were able to demonstrate generalization of the underlying grammar. For learners with normal language, both those in the high and the low variability groups showed generalization of the grammar, but relative effect sizes suggested a larger learning effect in the high variability group. The results demonstrate that the structure of the learning context can determine the ability to generalize from specific training items to novel cases.

  7. A deep learning and novelty detection framework for rapid phenotyping in high-content screening

    Science.gov (United States)

    Sommer, Christoph; Hoefler, Rudolf; Samwer, Matthias; Gerlich, Daniel W.

    2017-01-01

    Supervised machine learning is a powerful and widely used method for analyzing high-content screening data. Despite its accuracy, efficiency, and versatility, supervised machine learning has drawbacks, most notably its dependence on a priori knowledge of expected phenotypes and time-consuming classifier training. We provide a solution to these limitations with CellCognition Explorer, a generic novelty detection and deep learning framework. Application to several large-scale screening data sets on nuclear and mitotic cell morphologies demonstrates that CellCognition Explorer enables discovery of rare phenotypes without user training, which has broad implications for improved assay development in high-content screening. PMID:28954863

  8. Machine Learning on Signal-to-Noise Ratios Improves Peptide Array Design in SAMDI Mass Spectrometry.

    Science.gov (United States)

    Xue, Albert Y; Szymczak, Lindsey C; Mrksich, Milan; Bagheri, Neda

    2017-09-05

    Emerging peptide array technologies are able to profile molecular activities within cell lysates. However, the structural diversity of peptides leads to inherent differences in peptide signal-to-noise ratios (S/N). These complex effects can lead to potentially unrepresentative signal intensities and can bias subsequent analyses. Within mass spectrometry-based peptide technologies, the relation between a peptide's amino acid sequence and S/N remains largely nonquantitative. To address this challenge, we present a method to quantify and analyze mass spectrometry S/N of two peptide arrays, and we use this analysis to portray quality of data and to design future arrays for SAMDI mass spectrometry. Our study demonstrates that S/N varies significantly across peptides within peptide arrays, and variation in S/N is attributable to differences of single amino acids. We apply supervised machine learning to predict peptide S/N based on amino acid sequence, and identify specific physical properties of the amino acids that govern variation of this metric. We find low peptide-S/N concordance between arrays, demonstrating that different arrays require individual characterization and that global peptide-S/N relationships are difficult to identify. However, with proper peptide sampling, this study illustrates how machine learning can accurately predict the S/N of a peptide in an array, allowing for the efficient design of arrays through selection of high S/N peptides.

  9. Rapid determination of benzodiazepines, zolpidem and their metabolites in urine using direct injection liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Jeong, Yu-Dong; Kim, Min Kyung; Suh, Sung Ill; In, Moon Kyo; Kim, Jin Young; Paeng, Ki-Jung

    2015-12-01

    Benzodiazepines and zolpidem are generally prescribed as sedative, hypnotics, anxiolytics or anticonvulsants. These drugs, however, are frequently misused in drug-facilitated crime. Therefore, a rapid and simple liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed for identification and quantification of benzodiazepines, zolpidem and their metabolites in urine using deuterium labeled internal standards (IS). Urine samples (120 μL) mixed with 80 μL of the IS solution were centrifuged. An aliquot (5 μL) of the sample solution was directly injected into the LC-MS/MS system for analysis. The mobile phases consisted of water and acetonitrile containing 2mM ammonium trifluoroacetate and 0.2% acetic acid. The analytical column was a Zorbax SB-C18 (100 mm × 2.1 mm i.d., 3.5 μm, Agilent). The separation and detection of 18 analytes were achieved within 10 min. Calibration curves were linear over the concentration ranges of 0.5-20 ng/mL (zolpidem), 1.0-40 ng/mL (flurazepam and temazepam), 2.5-100 ng/mL (7-aminoclonazepam, 1-hydroxymidazolam, midazolam, flunitrazepam and alprazolam), 5.0-200 ng/mL (zolpidem phenyl-4-carboxylic acid, α-hydroxyalprazolam, oxazepam, nordiazepam, triazolam, diazepam and α-hydroxytriazolam), 10-400 ng/mL (lorazepam and desalkylflurazepam) and 10-100 ng/mL (N-desmethylflunitrazepam) with the coefficients of determination (r(2)) above 0.9971. The dilution integrity of the analytes was examined for supplementation of short linear range. Dilution precision and accuracy were tested using two, four and ten-folds dilutions and they ranged from 3.7 to 14.4% and -12.8 to 12.5%, respectively. The process efficiency for this method was 63.0-104.6%. Intra- and inter-day precisions were less than 11.8% and 9.1%, while intra- and inter-day accuracies were less than -10.0 to 8.2%, respectively. The lower limits of quantification were lower than 10 ng/mL for each analyte. The applicability of the developed method was successfully

  10. Reverse transcription-PCR-electrospray ionization mass spectrometry for rapid detection of biothreat and common respiratory pathogens.

    Science.gov (United States)

    Jeng, Kevin; Hardick, Justin; Rothman, Richard; Yang, Samuel; Won, Helen; Peterson, Stephen; Hsieh, Yu-Hsiang; Masek, Billie Jo; Carroll, Karen C; Gaydos, Charlotte A

    2013-10-01

    Electrospray ionization mass spectrometry (ESI-MS) analysis of reverse transcription (RT)-PCR amplicons from human respiratory samples allows for broad pathogen identification approximately 8 h after collection. We investigated the performance characteristics of a high-throughput RT-PCR-coupled ESI-MS assay for distinguishing biothreat (BT) agents from common bacterial, fungal, and viral respiratory pathogens in bronchoalveolar lavage (BAL) fluid specimens from subjects with suspected respiratory infections. In a retrospective case series, 202 BAL fluid specimens were collected at the Johns Hopkins Hospital between August 2010 and February 2011 from patients with suspected acute respiratory infections. Samples were processed using standard bacterial, viral, and fungal testing in the clinical microbiology laboratory as part of routine care and then were blindly spiked with either water or nucleic acids from BT organisms (Bacillus anthracis, Yersinia pestis, Francisella tularensis, Brucella spp., Burkholderia spp., and Rickettsia prowazekii) and tested by RT-PCR-ESI-MS. The sensitivities and specificities of RT-PCR-ESI-MS versus standard clinical methods were as follows: for mock BT DNA, 98.5% sensitivity (95% confidence interval [CI], 94.2 to 99.7%) and 100% specificity (95% CI, 93.1 to 100.0%); for bacterial pathogens, 81.8% sensitivity (95% CI, 74.3 to 87.6%) and 73.6% specificity (95% CI, 64.2 to 81.4%); for viral pathogens, 93.3% sensitivity (95% CI, 66.0 to 99.7%) and 97.3% specificity (95% CI, 89.7 to 99.5%); for fungal pathogens, 42.6% sensitivity (95% CI, 29.5 to 56.7%) and 97.8% specificity (95% CI, 91.8 to 99.6%). Our data suggest that RT-PCR-ESI-MS is a useful adjunct to standard culture protocols for rapid detection of both BT and common respiratory pathogens; further study is required for assay validation, especially for fungal detection, and potential implementation.

  11. Reverse Transcription-PCR–Electrospray Ionization Mass Spectrometry for Rapid Detection of Biothreat and Common Respiratory Pathogens

    Science.gov (United States)

    Jeng, Kevin; Rothman, Richard; Yang, Samuel; Won, Helen; Peterson, Stephen; Hsieh, Yu-Hsiang; Masek, Billie Jo; Carroll, Karen C.; Gaydos, Charlotte A.

    2013-01-01

    Electrospray ionization mass spectrometry (ESI-MS) analysis of reverse transcription (RT)-PCR amplicons from human respiratory samples allows for broad pathogen identification approximately 8 h after collection. We investigated the performance characteristics of a high-throughput RT-PCR-coupled ESI-MS assay for distinguishing biothreat (BT) agents from common bacterial, fungal, and viral respiratory pathogens in bronchoalveolar lavage (BAL) fluid specimens from subjects with suspected respiratory infections. In a retrospective case series, 202 BAL fluid specimens were collected at the Johns Hopkins Hospital between August 2010 and February 2011 from patients with suspected acute respiratory infections. Samples were processed using standard bacterial, viral, and fungal testing in the clinical microbiology laboratory as part of routine care and then were blindly spiked with either water or nucleic acids from BT organisms (Bacillus anthracis, Yersinia pestis, Francisella tularensis, Brucella spp., Burkholderia spp., and Rickettsia prowazekii) and tested by RT-PCR–ESI-MS. The sensitivities and specificities of RT-PCR–ESI-MS versus standard clinical methods were as follows: for mock BT DNA, 98.5% sensitivity (95% confidence interval [CI], 94.2 to 99.7%) and 100% specificity (95% CI, 93.1 to 100.0%); for bacterial pathogens, 81.8% sensitivity (95% CI, 74.3 to 87.6%) and 73.6% specificity (95% CI, 64.2 to 81.4%); for viral pathogens, 93.3% sensitivity (95% CI, 66.0 to 99.7%) and 97.3% specificity (95% CI, 89.7 to 99.5%); for fungal pathogens, 42.6% sensitivity (95% CI, 29.5 to 56.7%) and 97.8% specificity (95% CI, 91.8 to 99.6%). Our data suggest that RT-PCR–ESI-MS is a useful adjunct to standard culture protocols for rapid detection of both BT and common respiratory pathogens; further study is required for assay validation, especially for fungal detection, and potential implementation. PMID:23903543

  12. Characterizing the Performance of a Proton-Transfer-Reaction Mass Spectrometer with a Rapid Cycling Tenax Preconcentrator

    Energy Technology Data Exchange (ETDEWEB)

    Garland, S.P.; Alexander, M.L.

    2006-01-01

    Volatile organic compounds (VOCs) are species of interest for atmospheric modeling, worker chemical exposure and medical studies. Sometimes the required detection limits for these compounds is below the capability of existing real-time instrumentation. Preconcentrators have been implemented as an inexpensive way to amplify chemical signals and improve detection limits. Proton-transfer-reaction mass spectrometry (PTR-MS) has been used as a tool for studying low concentrations of VOCs, but it lacks the capability to differentiate chemical signal contributions from isobaric compounds. In this work, behavior of a newly designed Tenax TA preconcentrator when coupled with a PTRMS is characterized. This novel preconcentrator design allows rapid temperature cycling, maintaining near real-time response. The preconcentrator was exposed to a sample gas of toluene in varying concentrations and loading times between and then thermally desorbed for analysis by PTR-MS. The effects of preconcentrating multiple analytes simultaneously were also investigated as well as the chromatographic effects of the preconcentrator. A linear behavior was observed when the integrated ion count rates (ICPS) from thermal desorption peaks were regressed against both varying loading times at a constant toluene concentration and varying concentrations with constant loading times. From these trends, it is possible to determine the concentration of a VOC by knowing its ICPS from thermal desorption peaks from a known preconcentration time. Peak height ion count rates representing ultimate detectability were amplified by factors up to 257 times the original signal, extending the range of the PTR-MS from 50pptv to nearly 250 parts per quadrillion. This corresponds to an ultimate sensitivity of 200 parts per quadrillion with 20 minute time resolution. Quantitative preconcentrator behavior was demonstrated using ICPS from these ion peaks and were amplified as much as 148 times their original signal. Results

  13. Health co-benefits in mortality avoidance from implementation of the mass rapid transit (MRT) system in Kuala Lumpur, Malaysia.

    Science.gov (United States)

    Kwan, Soo Chen; Tainio, Marko; Woodcock, James; Hashim, Jamal Hisham

    2016-03-01

    The mass rapid transit (MRT) is the largest transport infrastructure project under the national key economic area (NKEA) in Malaysia. As urban rail is anticipated to be the future spine of public transport network in the Greater Kuala Lumpur city, it is important to mainstream climate change mitigation and public health benefits in the local transport development. This study quantifies the health co-benefits in terms of mortality among the urbanites when the first line of the 150 km MRT system in Kuala Lumpur commences by 2017. Using comparative health risk assessment, we estimated the potential health co-benefits from the establishment of the MRT system. We estimated the reduced CO2 emissions and air pollution (PM2.5) exposure reduction among the general population from the reduced use of motorized vehicles. Mortality avoided from traffic incidents involving motorcycles and passenger cars, and from increased physical activity from walking while using the MRT system was also estimated. A total of 363,130 tonnes of CO2 emissions could be reduced annually from the modal shift from cars and motorcycles to the MRT system. Atmospheric PM2.5 concentration could be reduced 0.61 μg/m3 annually (2%). This could avoid a total of 12 deaths, mostly from cardio-respiratory diseases among the city residents. For traffic injuries, 37 deaths could be avoided annually from motorcycle and passenger cars accidents especially among the younger age categories (aged 15-30). One additional death was attributed to pedestrian walking. The additional daily physical activity to access the MRT system could avoid 21 deaths among its riders. Most of the mortality avoided comes from cardiovascular diseases. Overall, a total of 70 deaths could be avoided annually among both the general population and the MRT users in the city. The implementation of the MRT system in Greater Kuala Lumpur could bring substantial health co-benefits to both the general population and the MRT users mainly from the

  14. The disk wind in the rapidly spinning stellar-mass black hole 4U 1630-472 observed with NuSTAR

    DEFF Research Database (Denmark)

    King, Ashley L.; Walton, Dominic J.; Miller, Jon M.

    2014-01-01

    We present an analysis of a short NuSTAR observation of the stellar-mass black hole and low-mass X-ray binary 4U 1630-472. Reflection from the inner accretion disk is clearly detected for the first time in this source, owing to the sensitivity of NuSTAR. With fits to the reflection spectrum, we...... find evidence for a rapidly spinning black hole, (1σ statistical errors). However, archival data show that the source has relatively low radio luminosity. Recently claimed relationships between jet power and black hole spin would predict either a lower spin or a higher peak radio luminosity. We also...

  15. Dynamic solid phase microextraction for sampling of airborne sarin with gas chromatography-mass spectrometry for rapid field detection and quantification.

    Science.gov (United States)

    Hook, Gary L; Jackson Lepage, Carmela; Miller, Stephen I; Smith, Philip A

    2004-08-01

    A portable dynamic air sampler and solid phase microextraction were used to simultaneously detect, identify, and quantify airborne sarin with immediate analysis of samples using a field portable gas chromatography-mass spectrometry system. A mathematical model was used with knowledge of the mass of sarin trapped, linear air velocity past the exposed sampling fiber, and sample duration allowing calculation of concentration estimates. For organizations with suitable field portable instrumentation, these methods are potentially useful for rapid onsite detection and quantification of high concern analytes, either through direct environmental sampling or through sampling of air collected in bags.

  16. Detection of Gelatin Adulteration in Traditional Chinese Medicine: Analysis of Deer-Horn Glue by Rapid-Resolution Liquid Chromatography-Triple Quadrupole Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Jia Chen

    2015-01-01

    Full Text Available Simultaneous identification of donkey-hide gelatin and bovine-hide gelatin in deer-horn glue was established by rapid-resolution liquid chromatography-triple quadrupole mass spectrometry. Water containing 1% NH4HCO3 was used for sample dissolution and trypsin was used for hydrolysis of the gelatins. After separation by a SB-C18 reversed-phase analytical column, collagen marker peptides were detected by mass spectrometry in positive electrospray ionization mode with multiple reaction monitoring. The method was specific, precise and reliable, and suitable for detection of adulterants derived from donkey-hide gelatin and bovine-hide gelatin in deer-horn glue.

  17. Phoneme Awareness, Visual-Verbal Paired-Associate Learning, and Rapid Automatized Naming as Predictors of Individual Differences in Reading Ability

    Science.gov (United States)

    Warmington, Meesha; Hulme, Charles

    2012-01-01

    This study examines the concurrent relationships between phoneme awareness, visual-verbal paired-associate learning, rapid automatized naming (RAN), and reading skills in 7- to 11-year-old children. Path analyses showed that visual-verbal paired-associate learning and RAN, but not phoneme awareness, were unique predictors of word recognition,…

  18. Rapid Screening of Multiclass Syrup Adulterants in Honey by Ultrahigh-Performance Liquid Chromatography/Quadrupole Time of Flight Mass Spectrometry.

    Science.gov (United States)

    Du, Bing; Wu, Liming; Xue, Xiaofeng; Chen, Lanzhen; Li, Yi; Zhao, Jing; Cao, Wei

    2015-07-29

    Honey adulteration with sugar syrups is a widespread problem. Several types of syrups have been used in honey adulteration, and there is no available method that can simultaneously detect all of these adulterants. In this study, we generated a small-scale database containing the specific chromatographic and mass spectrometry information on sugar syrup markers and developed a simple, rapid, and effective ultrahigh-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UHPLC/Q-TOF-MS) method for the detection of adulterated honey. Corn syrup, high-fructose corn syrup, inverted syrup, and rice syrup were used as honey adulterants; polysaccharides, difructose anhydrides, and 2-acetylfuran-3-glucopyranoside were used as detection markers. The presence of 10% sugar syrup in honey could be easily detected in <30 min using the developed method. The results revealed that UHPLC/Q-TOF-MS was simple and rapid.

  19. Performance Contracts -- Success or Failure. Contract Learning Projects, Grand Rapids Public Schools, 1970-72.

    Science.gov (United States)

    Webster, Joan M.

    This report evaluates the Grand Rapids Public School (GRPS) experience with performance contracting. The report describes the first two years of the GRPS performance contracting experience, assesses the accomplishments of those two years, and describes the third year (1972-73) program. The author concludes that the contracts were successful and…

  20. Rapid Learning of an Abstract Language-Specific Category: Polish Children's Acquisition of the Instrumental Construction

    Science.gov (United States)

    Dabrowska, Ewa; Tomasello, Michael

    2008-01-01

    Rapid acquisition of linguistic categories or constructions is sometimes regarded as evidence of innate knowledge. In this paper, we examine Polish children's early understanding of an idiosyncratic, language-specific construction involving the instrumental case--which could not be due to innate knowledge. Thirty Polish-speaking children aged 2; 6…

  1. Rapid analysis of formic acid, acetic acid, and furfural in pretreated wheat straw hydrolysates and ethanol in a bioethanol fermentation using atmospheric pressure chemical ionisation mass spectrometry

    Science.gov (United States)

    2011-01-01

    Atmospheric pressure chemical ionisation mass spectrometry (APCI-MS) offers advantages as a rapid analytical technique for the quantification of three biomass degradation products (acetic acid, formic acid and furfural) within pretreated wheat straw hydrolysates and the analysis of ethanol during fermentation. The data we obtained using APCI-MS correlated significantly with high-performance liquid chromatography analysis whilst offering the analyst minimal sample preparation and faster sample throughput. PMID:21896164

  2. Rapid Characterization of Microalgae and Microalgae Mixtures Using Matrix-Assisted Laser Desorption Ionization Time-Of-Flight Mass Spectrometry (MALDI-TOF MS).

    Science.gov (United States)

    Barbano, Duane; Diaz, Regina; Zhang, Lin; Sandrin, Todd; Gerken, Henri; Dempster, Thomas

    2015-01-01

    Current molecular methods to characterize microalgae are time-intensive and expensive. Matrix Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) may represent a rapid and economical alternative approach. The objectives of this study were to determine whether MALDI-TOF MS can be used to: 1) differentiate microalgae at the species and strain levels and 2) characterize simple microalgal mixtures. A common protein extraction sample preparation method was used to facilitate rapid mass spectrometry-based analysis of 31 microalgae. Each yielded spectra containing between 6 and 56 peaks in the m/z 2,000 to 20,000 range. The taxonomic resolution of this approach appeared higher than that of 18S rDNA sequence analysis. For example, two strains of Scenedesmus acutus differed only by two 18S rDNA nucleotides, but yielded distinct MALDI-TOF mass spectra. Mixtures of two and three microalgae yielded relatively complex spectra that contained peaks associated with members of each mixture. Interestingly, though, mixture-specific peaks were observed at m/z 11,048 and 11,230. Our results suggest that MALDI-TOF MS affords rapid characterization of individual microalgae and simple microalgal mixtures.

  3. Rapid Characterization of Microalgae and Microalgae Mixtures Using Matrix-Assisted Laser Desorption Ionization Time-Of-Flight Mass Spectrometry (MALDI-TOF MS)

    Science.gov (United States)

    Barbano, Duane; Diaz, Regina; Zhang, Lin; Sandrin, Todd; Gerken, Henri; Dempster, Thomas

    2015-01-01

    Current molecular methods to characterize microalgae are time-intensive and expensive. Matrix Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) may represent a rapid and economical alternative approach. The objectives of this study were to determine whether MALDI-TOF MS can be used to: 1) differentiate microalgae at the species and strain levels and 2) characterize simple microalgal mixtures. A common protein extraction sample preparation method was used to facilitate rapid mass spectrometry-based analysis of 31 microalgae. Each yielded spectra containing between 6 and 56 peaks in the m/z 2,000 to 20,000 range. The taxonomic resolution of this approach appeared higher than that of 18S rDNA sequence analysis. For example, two strains of Scenedesmus acutus differed only by two 18S rDNA nucleotides, but yielded distinct MALDI-TOF mass spectra. Mixtures of two and three microalgae yielded relatively complex spectra that contained peaks associated with members of each mixture. Interestingly, though, mixture-specific peaks were observed at m/z 11,048 and 11,230. Our results suggest that MALDI-TOF MS affords rapid characterization of individual microalgae and simple microalgal mixtures. PMID:26271045

  4. Learning to Read in Spanish: Contributions of Phonological Awareness, Orthographic Coding, and Rapid Naming

    Science.gov (United States)

    Clinton, Amanda; Christo, Catherine; Shriberg, David

    2013-01-01

    During the past 2 decades, many respective reading processes have been delineated, and much is now known about reading acquisition in children. Most of this research has been completed using English-dominant subjects. As such, the literature focuses on an opaque orthography and aspects of learning to read in this context. In this study, predictors…

  5. Using MALDI-TOF mass spectrometry as a rapid and accurate diagnostic tool in infective endocarditis: a case report of a patient with mitral valve infective endocarditis caused by Abiotrophia defectiva

    DEFF Research Database (Denmark)

    Holler, Jon Gitz; Pedersen, Line; Calum, Henrik

    2011-01-01

    A case of infective endocarditis caused by Abiotrophia defectiva is presented. The use of MALDI-TOF mass spectrometry as a rapid and accurate diagnostic tool in infective endocarditis is discussed.......A case of infective endocarditis caused by Abiotrophia defectiva is presented. The use of MALDI-TOF mass spectrometry as a rapid and accurate diagnostic tool in infective endocarditis is discussed....

  6. Sustaining Health Care Interventions to Achieve Quality Care: What We Can Learn From Rapid Response Teams.

    Science.gov (United States)

    Stolldorf, Deonni P

    Rapid response team (RRT) adoption and implementation are associated with improved quality of care of patients who experience an unanticipated medical emergency. The sustainability of RRTs is vital to achieve long-term benefits of these teams for patients, staff, and hospitals. Factors required to achieve RRT sustainability remain unclear. This study examined the relationship between sustainability elements and RRT sustainability in hospitals that have previously implemented RRTs.

  7. Evaluation of Flow-Injection Tandem Mass Spectrometry for Rapid and High-Throughput Quantitative Determination of B-Vitamins in Nutritional Supplements

    Energy Technology Data Exchange (ETDEWEB)

    Bhandari, Deepak [ORNL; Van Berkel, Gary J [ORNL

    2012-01-01

    The use of flow-injection electrospray ionization tandem mass spectrometry for rapid and high-throughput mass spectral analysis of selected B-vitamins, viz. B1, B2, B3, B5, and B6, in nutritional formulations was demonstrated. A simple and rapid (~5 min) in-tube sample preparation was performed by adding extraction solvent to a powdered sample aliquot followed by agitation, centrifugation, and filtration to recover an extract for analysis. Automated flow injection introduced 1 L of the extracts directly into the mass spectrometer ion source without chromatographic separation. Sample-to-sample analysis time was 60 s representing significant improvement over conventional liquid chromatography approaches which typically require 25-45 min, and often require more significant sample preparation procedures. Quantitative capabilities of the flow-injection analysis were tested using the method of standard additions and NIST standard reference material (SRM 3280) multivitamin/multielement tablets. The quantity determined for each B-vitamin in SRM 3280 was within the statistical range provided for the respective certified values. The same sample preparation and analysis approach was also applied to two different commercial vitamin supplement tablets and proved to be successful in the quantification of the selected B-vitamins as evidenced by an agreement with the labels values and the results obtained using isotope dilution liquid chromatography/mass spectrometry.

  8. Rapid profiling of polymeric phenolic acids in Salvia miltiorrhiza by hybrid data-dependent/targeted multistage mass spectrometry acquisition based on expected compounds prediction and fragment ion searching.

    Science.gov (United States)

    Shen, Yao; Feng, Zijin; Yang, Min; Zhou, Zhe; Han, Sumei; Hou, Jinjun; Li, Zhenwei; Wu, Wanying; Guo, De-An

    2018-01-15

    Phenolic acids are the major water-soluble components in Salvia miltiorrhiza (> 5%). According to previous studies, many of them contribute to the cardiovascular effects and antioxidant effects of S. miltiorrhiza. Polymeric phenolic acids can be considered as the tanshinol derived metabolites, e.g., dimmers, trimers and tetramers. A strategy combined with tanshinol-based expected compounds prediction, total ion chromatogram filtering, Fragment Ion Searching and parent list-based multistage mass spectrometry acquisition by Linear Trap Quadropole-orbitrap Velos Mass Spectrometry was proposed to rapid profile polymeric phenolic acids in S. miltiorrhiza. More than 480 potential polymeric phenolic acids could be screened out by this strategy. Based on the fragment information obtained by parent list-activated data dependent multistage mass spectrometry acquisition, 190 polymeric phenolic acids were characterized by comparing their mass information with literature data, and 18 of them were firstly detected from S. miltiorrhiza. Seven potential compounds were tentatively characterized as new polymeric phenolic acids from S. miltiorrhiza. This strategy facilitates identification of polymeric phenolic acids in complex matrix with both selectivity and sensitivity, which could be expanded for rapid discovery and identification of compounds from complex matrix. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  9. Rapid Detection of Gas Hazards and Leaks with an Atmospheric Sampling, High Resolution, Mass Spectrometer with Low Pumping Requirements Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Miniaturization of mass spectrometers is restricted almost exclusively by the ability of small vacuum pumps to remove gas loads during operation of the instrument....

  10. Rapid and Deep Proteomes by Faster Sequencing on a Benchtop Quadrupole Ultra-High-Field Orbitrap Mass Spectrometer

    DEFF Research Database (Denmark)

    Kelstrup, Christian D; Jersie-Christensen, Rosa R; Batth, Tanveer Singh

    2014-01-01

    Shotgun proteomics is a powerful technology for global analysis of proteins and their post-translational modifications. Here, we investigate faster sequencing speed of the latest Q Exactive HF mass spectrometer, which features an ultra-high-field Orbitrap mass analyzer. Proteome coverage is evalu......Shotgun proteomics is a powerful technology for global analysis of proteins and their post-translational modifications. Here, we investigate faster sequencing speed of the latest Q Exactive HF mass spectrometer, which features an ultra-high-field Orbitrap mass analyzer. Proteome coverage...... in less than 24 hours of analysis time by offline high pH reversed-phase peptide fractionation from which we identify more than 140,000 unique peptide sequences. This is comparable to state-of-the-art multi-day, multi-enzyme efforts. Finally the acquisition methods are evaluated for single-shot...

  11. Rapid and Deep Proteomes by Faster Sequencing on a Benchtop Quadrupole Ultra-High-Field Orbitrap Mass Spectrometer

    DEFF Research Database (Denmark)

    Kelstrup, Christian D; Jersie-Christensen, Rosa R; Batth, Tanveer Singh

    2014-01-01

    Shotgun proteomics is a powerful technology for global analysis of proteins and their post-translational modifications. Here, we investigate faster sequencing speed of the latest Q Exactive HF mass spectrometer, which features an ultra-high-field Orbitrap mass analyzer. Proteome coverage is evalu......Shotgun proteomics is a powerful technology for global analysis of proteins and their post-translational modifications. Here, we investigate faster sequencing speed of the latest Q Exactive HF mass spectrometer, which features an ultra-high-field Orbitrap mass analyzer. Proteome coverage...... per second or up to 600 new peptides sequenced per gradient minute. We identify 4400 proteins from one microgram of HeLa digest using a one hour gradient, which is an approximately 30% improvement compared to previous instrumentation. In addition, we show very deep proteome coverage can be achieved...

  12. The Athena Breast Health Network: developing a rapid learning system in breast cancer prevention, screening, treatment, and care.

    Science.gov (United States)

    Elson, Sarah L; Hiatt, Robert A; Anton-Culver, Hoda; Howell, Lydia P; Naeim, Arash; Parker, Barbara A; Van't Veer, Laura J; Hogarth, Michael; Pierce, John P; Duwors, Robert J; Hajopoulos, Kathy; Esserman, Laura J

    2013-07-01

    The term breast cancer covers many different conditions, whose clinical course ranges from indolent to aggressive. However, current practice in breast cancer prevention and care, and in breast cancer epidemiology, does not take into account the heterogeneity of the disease. A comprehensive understanding of the etiology and progression of different breast cancer subtypes would enable a more patient-centered approach to breast health care: assessing an individual's risk of getting specific subtypes of the disease, providing risk-based screening and prevention recommendations, and, for those diagnosed with the disease, tailored treatment options based on risk and timing of progression and mortality. The Athena Breast Health Network is an initiative of the five University of California medical and cancer centers to prototype this approach and to enable the development of a rapid learning system-connecting risk and outcome information from a heterogeneous patient population in real time and using new knowledge from research to continuously improve the quality of care. The Network is based on integrating clinical and research processes to create a comprehensive approach to accelerating patient-centered breast health care. Since its inception in 2009, the Network has developed a multi-site, transdisciplinary collaboration that enables the learning system. The five-campus collaboration has implemented a shared informatics platform, standardized electronic patient intake questionnaires, and common biospecimen protocols, as well as new clinical programs and multi-center research projects. The Athena Breast Health Network can serve as a model of a rapid learning system that integrates epidemiologic, behavioral, and clinical research with clinical care improvements.

  13. Direct Infusion Electrospray Ionization - Ion Mobility - High Resolution Mass Spectrometry (DIESI-IM-HRMS) for Rapid Characterization of Potential Bioprocess Streams

    Science.gov (United States)

    Munisamy, Sharon M.; Chambliss, C. Kevin; Becker, Christopher

    2012-07-01

    Direct infusion electrospray ionization - ion mobility - high resolution mass spectrometry (DIESI-IM-HRMS) has been utilized as a rapid technique for the characterization of total molecular composition in "whole-sample" biomass hydrolysates and extracts. IM-HRMS data reveal a broad molecular weight distribution of sample components (up to 1100 m/z) and provide trendline isolation of feedstock components from those introduced "in process." Chemical formulas were obtained from HRMS exact mass measurements (with typical mass error less than 5 ppm) and were consistent with structural carbohydrates and other lignocellulosic degradation products. Analyte assignments are supported via IM-MS collision-cross-section measurements and trendline analysis (e.g., all carbohydrate oligomers identified in a corn stover hydrolysate were found to fall within 6 % of an average trendline). These data represent the first report of collision cross sections for several negatively charged carbohydrates and other acidic species occurring natively in biomass hydrolysates.

  14. Rapid Prediction of Bacterial Heterotrophic Fluxomics Using Machine Learning and Constraint Programming.

    Directory of Open Access Journals (Sweden)

    Stephen Gang Wu

    2016-04-01

    Full Text Available 13C metabolic flux analysis (13C-MFA has been widely used to measure in vivo enzyme reaction rates (i.e., metabolic flux in microorganisms. Mining the relationship between environmental and genetic factors and metabolic fluxes hidden in existing fluxomic data will lead to predictive models that can significantly accelerate flux quantification. In this paper, we present a web-based platform MFlux (http://mflux.org that predicts the bacterial central metabolism via machine learning, leveraging data from approximately 100 13C-MFA papers on heterotrophic bacterial metabolisms. Three machine learning methods, namely Support Vector Machine (SVM, k-Nearest Neighbors (k-NN, and Decision Tree, were employed to study the sophisticated relationship between influential factors and metabolic fluxes. We performed a grid search of the best parameter set for each algorithm and verified their performance through 10-fold cross validations. SVM yields the highest accuracy among all three algorithms. Further, we employed quadratic programming to adjust flux profiles to satisfy stoichiometric constraints. Multiple case studies have shown that MFlux can reasonably predict fluxomes as a function of bacterial species, substrate types, growth rate, oxygen conditions, and cultivation methods. Due to the interest of studying model organism under particular carbon sources, bias of fluxome in the dataset may limit the applicability of machine learning models. This problem can be resolved after more papers on 13C-MFA are published for non-model species.

  15. Rapid enzymatic hydrolysis of masked deoxynivalenol and zearalenone prior to liquid chromatography mass spectrometry or immuniassay analysis

    NARCIS (Netherlands)

    Nielen, M.W.F.; Weijers, C.A.G.M.; Peters, J.; Weignerová, L.; Zuilhof, H.; Franssen, M.C.R.

    2014-01-01

    Recently it has been shown that conjugates (‘masked mycotoxins’) may contribute to the total daily intake of hazardous mycotoxins. Therefore, there is an urgent need for rapid analysis methods that assess the level of both free and masked mycotoxins in food and feed. However, the analysis of masked

  16. Rapid screening of chemical warfare nerve agent metabolites in urine by atmospheric solids analysis probe-mass spectroscopy (ASAP-MS).

    Science.gov (United States)

    Zydel, Frank; Smith, J Richard; Pagnotti, Vincent S; Lawrence, Richard J; McEwen, Charles N; Capacio, Benedict R

    2012-01-01

    Exposures to organophosphorus nerve agents (OPNA) remain a threat to both civilian and military populations. Verification of exposures typically involves determinations of urinary metabolites or adducted proteins in blood. Urinary alkyl methylphosphonic acid metabolites resulting from hydrolysis of OPNAs provide a convenient marker for OPNA exposure. In a military setting, urine is a relatively easy sample to obtain, and a rapid turnaround for analyses for the identification of metabolites is critical for field commanders. Timely information on use and identity of OPNAs facilitates decisions regarding employment of personal protective equipment and additional strategies to mitigate additional exposure(s). Herein, we report the development of a rapid mass spectrometric (MS) method to identify OPNA metabolites directly from urine with no sample preparation. Synthetic urine spiked with multiple OPNA metabolites was analyzed using an atmospheric solids analysis probe (ASAP) attached to a high resolution mass spectrometer. The alkyl methylphosphonic acid metabolites resulting from hydrolysis of sarin, cyclosarin, soman, and Russian VX were clearly detectable down to a level of 1.0 ng/ml. The ability to rapidly detect OPNA metabolites in unprepared urine allows for the design of a field-deployable device that could afford field personnel the ability to rapidly screen individuals for specific OPNA exposure. In addition, this provides proof-of-concept evidence that a fieldable ASAP-MS device could afford personnel the ability to rapidly detect OPNAs on skin, equipment, and other porous surfaces. Published 2012. This article is a US Government work and is in the public domain in the USA. Copyright © 2012 John Wiley & Sons, Ltd.

  17. Active machine learning for rapid landslide inventory mapping with VHR satellite images (Invited)

    Science.gov (United States)

    Stumpf, A.; Lachiche, N.; Malet, J.; Kerle, N.; Puissant, A.

    2013-12-01

    VHR satellite images have become a primary source for landslide inventory mapping after major triggering events such as earthquakes and heavy rainfalls. Visual image interpretation is still the prevailing standard method for operational purposes but is time-consuming and not well suited to fully exploit the increasingly better supply of remote sensing data. Recent studies have addressed the development of more automated image analysis workflows for landslide inventory mapping. In particular object-oriented approaches that account for spatial and textural image information have been demonstrated to be more adequate than pixel-based classification but manually elaborated rule-based classifiers are difficult to adapt under changing scene characteristics. Machine learning algorithm allow learning classification rules for complex image patterns from labelled examples and can be adapted straightforwardly with available training data. In order to reduce the amount of costly training data active learning (AL) has evolved as a key concept to guide the sampling for many applications. The underlying idea of AL is to initialize a machine learning model with a small training set, and to subsequently exploit the model state and data structure to iteratively select the most valuable samples that should be labelled by the user. With relatively few queries and labelled samples, an AL strategy yields higher accuracies than an equivalent classifier trained with many randomly selected samples. This study addressed the development of an AL method for landslide mapping from VHR remote sensing images with special consideration of the spatial distribution of the samples. Our approach [1] is based on the Random Forest algorithm and considers the classifier uncertainty as well as the variance of potential sampling regions to guide the user towards the most valuable sampling areas. The algorithm explicitly searches for compact regions and thereby avoids a spatially disperse sampling pattern

  18. Equipment and methods for rapid analysis of PWO full-sized scintillation crystal radiation hardness during mass production

    CERN Document Server

    Drobychev, G Yu; Fedorov, A; Korzhik, M V; Lecoq, P; Lopatik, A; Missevitch, O V; Peigneux, J P; Singovsky, A V; Zouevski, R F

    2001-01-01

    The mass production of lead tungstate crystals (PWO) for the Compact Muon Solenoid (CMS) Project at CERN began at the Bogoroditsk Techno- Chemical Plant (BTCP, Tula Region, Russia) in 2000. Mass production technology, developed in recent years, is based on a set of methods and instrumentation for crystal growth and machining, as well as quality control and certification of crystals. One of the most crucial categories of tolerances is the radiation hardness of crystals. Control of the PWO radiation hardness during the mass production phase requires a reliable, easy-to-use measuring tool with high productivity. A semiautomatic spectrometric setup for PWO radiation hardness monitoring was developed and tested at CERN. After final crosschecks, the setup was put into operation at BTCP. (13 refs).

  19. Precision Mass Measurements of 129-131Cd and Their Impact on Stellar Nucleosynthesis via the Rapid Neutron Capture Process

    CERN Document Server

    Atanasov, D.; Blaum, K.; Cakirli, R.B.; Cocolios, T.E.; George, S.; Herfurth, F.; Kisler, D.; Janka, H.T.; Just, O.; Kowalska, M.; Kreim, S.; Kisler, D.; Litvinov, Yu. A.; Lunney, D.; Manea, V.; Neidherr, D.; Rosenbusch, M.; Schweikhard, L.; Welker, A.; Wienholtz, F.; Wolf, R. N.; Zuber, K.

    2015-01-01

    Masses adjacent to the classical waiting-point nuclide 130Cd have been measured by using the Penning- trap spectrometer ISOLTRAP at ISOLDE/CERN. We find a significant deviation of over 400 keV from earlier values evaluated by using nuclear beta-decay data. The new measurements show the reduction of the N = 82 shell gap below the doubly magic 132Sn. The nucleosynthesis associated with the ejected wind from type-II supernovae as well as from compact object binary mergers is studied, by using state-of-the-art hydrodynamic simulations. We find a consistent and direct impact of the newly measured masses on the calculated abundances in the A = 128 - 132 region and a reduction of the uncertainties from the precision mass input data.

  20. Endocytic pathway rapidly delivers internalized molecules to lysosomes: an analysis of vesicle trafficking, clustering and mass transfer.

    Science.gov (United States)

    Pangarkar, Chinmay; Dinh, Anh-Tuan; Mitragotri, Samir

    2012-08-20

    Lysosomes play a critical role in intracellular drug delivery. For enzyme-based therapies, they represent a potential target site whereas for nucleic acid or many protein drugs, they represent the potential degradation site. Either way, understanding the mechanisms and processes involved in routing of materials to lysosomes after cellular entry is of high interest to the field of drug delivery. Most therapeutic cargoes other than small hydrophobic molecules enter the cells through endocytosis. Endocytosed cargoes are routed to lysosomes via microtubule-based transport and are ultimately shared by various lysosomes via tethering and clustering of endocytic vesicles followed by exchange of their contents. Using a combined experimental and numerical approach, here we studied the rates of mass transfer into and among the endocytic vesicles in a model cell line, 3T3 fibroblasts. In order to understand the relationship of mass transfer with microtubular transport and vesicle clustering, we varied both properties through various pharmacological agents. At the same time, microtubular transport and vesicle clustering were modeled through diffusion-advection equations and the Smoluchowski equations, respectively. Our analysis revealed that the rate of mass transfer is optimally related to microtubular transport and clustering properties of vesicles. Further, the rate of mass transfer is highest in the innate state of the cell. Any perturbation to either microtubular transport or vesicle aggregation led to reduced mass transfer to lysosome. These results suggest that in the absence of an external intervention the endocytic pathway appears to maximize molecular delivery to lysosomes. Strategies are discussed to reduce mass transfer to lysosomes so as to extend the residence time of molecules in endosomes or late endosomes, thus potentially increasing the likelihood of their escape before disposition in the lysosomes. Copyright © 2012 Elsevier B.V. All rights reserved.

  1. Young children learning Spanish make rapid use of grammatical gender in spoken word recognition.

    Science.gov (United States)

    Lew-Williams, Casey; Fernald, Anne

    2007-03-01

    All nouns in Spanish have grammatical gender, with obligatory gender marking on preceding articles (e.g., la and el, the feminine and masculine forms of "the," respectively). Adult native speakers of languages with grammatical gender exploit this cue in on-line sentence interpretation. In a study investigating the early development of this ability, Spanish-learning children (34-42 months) were tested in an eye-tracking procedure. Presented with pairs of pictures with names of either the same grammatical gender (la pelota, "ball [feminine]"; la galleta, "cookie [feminine]") or different grammatical gender (la pelota; el zapato, "shoe [masculine]"), they heard sentences referring to one picture (Encuentra la pelota, "Find the ball"). The children were faster to orient to the referent on different-gender trials, when the article was potentially informative, than on same-gender trials, when it was not, and this ability was correlated with productive measures of lexical and grammatical competence. Spanish-learning children who can speak only 500 words already use gender-marked articles in establishing reference, a processing advantage characteristic of native Spanish-speaking adults.

  2. A drop in the pond: the effect of rapid mass-loss on the dynamics and interaction rate of collisionless particles

    Science.gov (United States)

    Penoyre, Zephyr; Haiman, Zoltán

    2018-01-01

    In symmetric gravitating systems experiencing rapid mass-loss, particle orbits change almost instantaneously, which can lead to the development of a sharply contoured density profile, including singular caustics for collisionless systems. This framework can be used to model a variety of dynamical systems, such as accretion discs following a massive black hole merger and dwarf galaxies following violent early star formation feedback. Particle interactions in the high-density peaks seem a promising source of observable signatures of these mass-loss events (i.e. a possible EM counterpart for black hole mergers or strong gamma-ray emission from dark matter annihilation around young galaxies), because the interaction rate depends on the square of the density. We study post-mass-loss density profiles, both analytic and numerical, in idealized cases and present arguments and methods to extend to any general system. An analytic derivation is presented for particles on Keplerian orbits responding to a drop in the central mass. We argue that this case, with initially circular orbits, gives the most sharply contoured profile possible. We find that despite the presence of a set of singular caustics, the total particle interaction rate is reduced compared to the unperturbed system; this is a result of the overall expansion of the system dominating over the steep caustics. Finally, we argue that this result holds more generally, and the loss of central mass decreases the particle interaction rate in any physical system.

  3. Multicomponent mixed dopant optimization for rapid screening of polycyclic aromatic hydrocarbons using ultra high performance liquid chromatography coupled to atmospheric pressure photoionization high-resolution mass spectrometry

    KAUST Repository

    Sioud, Salim

    2012-05-04

    RATIONALE To enhance the ionization efficiencies in atmospheric pressure photoionization mass spectrometry a dopant with favorable ionization energy such as chlorobenzene is typically used. These dopants are typically toxic and difficult to mix with water-soluble organic solvents. In order to achieve a more efficient and less toxic dopant, a multicomponent mixed dopant was explored. METHODS A multicomponent mixed dopant for non-targeted rapid screening of polycyclic aromatic hydrocarbons (PAHs) was developed and optimized using ultra high performance liquid chromatography (UPLC) coupled to atmospheric pressure photoionization high-resolution mass spectrometry. Various single and multicomponent mixed dopants consisting of ethanol, chlorobenzene, bromobenzene, anisole and toluene were evaluated. RESULTS Fourteen out of eighteen PAHs were successfully separated and detected at low pg/μL levels within 5 min with high mass accuracy ≤4 ppm. The optimal mixed multicomponent dopant consisted of ethanol/chlorobenzene/bromobenzene/anisole (98.975:0.1:0.9:0.025, v/v %) and it improved the limit of detection (LOD) by 2- to 10-fold for the tested PAHs compared to those obtained with pure chlorobenzene. CONCLUSIONS A novel multicomponent dopant that contains 99% ethanol and 1% mixture of chlorobenzene, bromobenzene and anisole was found to be an effective dopant mixture to ionize PAHs. The developed UPLC multicomponent dopant assisted atmospheric pressure photoionization high-resolution mass spectrometry offered a rapid non targeted screening method for detecting the PAHs at low pg/;μL levels within a 5 min run time with high mass accuracy a;circ4 ppm. Copyright © 2012 John Wiley & Sons, Ltd.

  4. Multicomponent mixed dopant optimization for rapid screening of polycyclic aromatic hydrocarbons using ultra high performance liquid chromatography coupled to atmospheric pressure photoionization high-resolution mass spectrometry.

    Science.gov (United States)

    Sioud, Salim; Amad, Ma'an; Al-Talla, Zeyad A

    2012-06-30

    To enhance the ionization efficiencies in atmospheric pressure photoionization mass spectrometry a dopant with favorable ionization energy such as chlorobenzene is typically used. These dopants are typically toxic and difficult to mix with water-soluble organic solvents. In order to achieve a more efficient and less toxic dopant, a multicomponent mixed dopant was explored. A multicomponent mixed dopant for non-targeted rapid screening of polycyclic aromatic hydrocarbons (PAHs) was developed and optimized using ultra high performance liquid chromatography (UPLC) coupled to atmospheric pressure photoionization high-resolution mass spectrometry. Various single and multicomponent mixed dopants consisting of ethanol, chlorobenzene, bromobenzene, anisole and toluene were evaluated. Fourteen out of eighteen PAHs were successfully separated and detected at low pg/μL levels within 5 min with high mass accuracy ≤4 ppm. The optimal mixed multicomponent dopant consisted of ethanol/chlorobenzene/bromobenzene/anisole (98.975:0.1:0.9:0.025, v/v %) and it improved the limit of detection (LOD) by 2- to 10-fold for the tested PAHs compared to those obtained with pure chlorobenzene. A novel multicomponent dopant that contains 99% ethanol and 1% mixture of chlorobenzene, bromobenzene and anisole was found to be an effective dopant mixture to ionize PAHs. The developed UPLC multicomponent dopant assisted atmospheric pressure photoionization high-resolution mass spectrometry offered a rapid non targeted screening method for detecting the PAHs at low pg/μL levels within a 5 min run time with high mass accuracy ≤4 ppm. Copyright © 2012 John Wiley & Sons, Ltd.

  5. [Rapid screening and identification of 22 allergenic disperse dyes in ecological textiles by high performance liquid chromatography-linear ion trap/orbitrap mass spectrometry].

    Science.gov (United States)

    Niu, Zengyuan; Luo, Xin; Ye, Xiwen; Xiu, Xiaoli; Zhang, Li; Wang, Xin; Chen, Jing

    2015-10-01

    A rapid screening method based on high performance liquid chromatography-linear ion trap/orbitrap high-resolution mass spectrometry (HPLC-LTQ/Orbitrap MS) for 22 disperse dyes in ecological textiles has been established. The target compounds were extracted by pyridine/water (1:1, v/v) by shaking extraction in 90 degrees C water bath. The extracts were then separated by a CAPCELL PAK C18 column (100 mm x 2.0 mm, 5 μm) using gradient elution with acetonitrile-5 mmol/L ammonium acetate containing 0.01% (v/v) formic acid as mobile phases, and finally analyzed by HPLC-LTQ/Orbitrap in positive and negative ESI modes. The retention time and accurate mass of parent ion were used for fast screening of 22 disperse dyes, while the confirmatory analysis was obtained by fragments generated by collision-induced dissociation (CID) MS/MS. Target analysis exhibited high mass accuracy (textiles, and Disperse Orange 37/76 was detected in one of them. With high selectivity and strong anti-jamming ability, this method is simple, rapid, accurate, and it can be used for the inspection of disperse dyes in textiles.

  6. [Rapid screening and confirming carcinogenic banned azo colorants in textiles by high performance liquid chromatography-linear ion trap/orbitrap high-resolution mass spectrometry].

    Science.gov (United States)

    Yun, Huan; Liu, Xin; Wang, Jing; Yan, Hua; Cui, Fengyun; Zhang, Zhaohui

    2013-09-01

    A method of high performance liquid chromatography-linear ion trap/orbitrap highresolution mass spectrometry (HPLC-LTP/Orbitrap MS) was ued to screen and confirm-banned azo colorants in textiles rapidly. The analytes were reduced to carcinogenic aromatic amines with sodium dithionite in citrate buffer solution. The reduced solution was extracted bydiatomite, and loadd onto an Acquity UPLC BEH C18 column (50 mm x 2.1 MM. 1.7 microm) with a gradient elution of methanol and 0.1% (v/v) methane acid aqueous solution, and finally detected by linear ion trap/orbitrap high-resolution mass spectrometry in positive ESI mode. In mass spectrometry method, the MS spectrum of high-resolution and the collision induced dissociation (CID) spectrum of data-dependent scan mode were used for screening analysis and conformation, respectively. The calibration curves showed a good linearity in the range of 0.05 -2.00 mg/b, and the correlation coefficients (r) were higher than 0.99. By detecting spiked samples, the limits of quantification were 0.08 mg/kg for all the residues and the recoveries were in the range of 65.5% - 111.5% with the relative standard deviations (RSDs) between 0.87% and 2.49%. The results indicate that the method is simple, rapid, sensitive and suitable for the qualitative and quantitative analysis of carcinogenic aromatic amines in textiles.

  7. UKF-based closed loop iterative learning control of epileptiform wave in a neural mass model.

    Science.gov (United States)

    Shan, Bonan; Wang, Jiang; Deng, Bin; Wei, Xile; Yu, Haitao; Li, Huiyan

    2015-02-01

    A novel closed loop control framework is proposed to inhibit epileptiform wave in a neural mass model by external electric field, where the unscented Kalman filter method is used to reconstruct dynamics and estimate unmeasurable parameters of the model. Specifically speaking, the iterative learning control algorithm is introduced into the framework to optimize the control signal. In the proposed method, the control effect can be significantly improved based on the observation of the past attempts. Accordingly, the proposed method can effectively suppress the epileptiform wave as well as showing robustness to noises and uncertainties. Lastly, the simulation is carried out to illustrate the feasibility of the proposed method. Besides, this work shows potential value to design model-based feedback controllers for epilepsy treatment.

  8. Rapid Patient Discharge Contribution to Bed Surge Capacity During a Mass Casualty Incident: Findings From an Exercise With New York City Hospitals.

    Science.gov (United States)

    Jacobs-Wingo, Jasmine L; Cook, Heather A; Lang, William H

    Mass casualty incidents may increase patient volume suddenly and dramatically, requiring hospitals to expeditiously manage bed inventories to release acute care beds for disaster victims. Electronic patient tracking systems combined with unit walk-throughs can identify patients for rapid discharge. The New York City (NYC) Department of Health and Mental Hygiene's 2013 Rapid Patient Discharge Assessment (RPDA) aimed to determine the maximum number of beds NYC hospitals could make available through rapid patient discharge and to characterize discharge barriers. Unit representatives identified discharge candidates within normal operations in round 1 and additional discharge candidates during a disaster scenario in round 2. Descriptive statistics were performed. Fifty-five NYC hospitals participated in the RPDA exercise; 45 provided discharge candidate counts in both rounds. Representatives identified 4225 patients through the RPDA: among these, 1138 (26.9%) were already confirmed for discharge; 1854 (43.9%) were round 1 discharge candidates; and 1233 (29.2%) were round 2 discharge candidates. These 4225 patients represented 21.4% of total bed capacity. Frequently reported barriers included missing prescriptions for aftercare or discharge orders. The NYC hospitals could implement rapid patient discharge to clear one-fifth of occupied inpatient beds for disaster victims, given they address barriers affecting patients' safe and efficient discharge.

  9. Low-mass vector-meson production at forward rapidity in $p$$+$$p$ collisions at $\\sqrt{s}=200$ GeV

    CERN Document Server

    Adare, A; Ajitanand, N N; Akiba, Y; Akimoto, R; Al-Ta'ani, H; Alexander, J; Alfred, M; Andrews, K R; Angerami, A; Aoki, K; Apadula, N; Appelt, E; Aramaki, Y; Armendariz, R; Asano, H; Aschenauer, E C; Atomssa, E T; Awes, T C; Azmoun, B; Babintsev, V; Bai, M; Bandara, N S; Bannier, B; Barish, K N; Bassalleck, B; Basye, A T; Bathe, S; Baublis, V; Baumann, C; Bazilevsky, A; Beaumier, M; Beckman, S; Belmont, R; Ben-Benjamin, J; Bennett, R; Berdnikov, A; Berdnikov, Y; Black, D; Blau, D S; Bok, J; Bok, J S; Boyle, K; Brooks, M L; Broxmeyer, D; Bryslawskyj, J; Buesching, H; Bumazhnov, V; Bunce, G; Butsyk, S; Campbell, S; Castera, P; Chen, C -H; Chi, C Y; Chiu, M; Choi, I J; Choi, J B; Choudhury, R K; Christiansen, P; Chujo, T; Chvala, O; Cianciolo, V; Citron, Z; Cole, B A; del Valle, Z Conesa; Connors, M; Csanád, M; Csörgő, T; Dairaku, S; Datta, A; Daugherity, M S; David, G; Dayananda, M K; DeBlasio, K; Dehmelt, K; Denisov, A; Deshpande, A; Desmond, E J; Dharmawardane, K V; Dietzsch, O; Ding, L; Dion, A; Do, J H; Donadelli, M; Drapier, O; Drees, A; Drees, K A; Durham, J M; Durum, A; D'Orazio, L; Efremenko, Y V; Engelmore, T; Enokizono, A; En'yo, H; Esumi, S; Fadem, B; Feege, N; Fields, D E; Finger, M; Jr., \\,; Fleuret, F; Fokin, S L; Frantz, J E; Franz, A; Frawley, A D; Fukao, Y; Fusayasu, T; Gal, C; Gallus, P; Garg, P; Garishvili, I; Ge, H; Giordano, F; Glenn, A; Gong, X; Gonin, M; Goto, Y; de Cassagnac, R Granier; Grau, N; Greene, S V; Perdekamp, M Grosse; Gu, Y; Gunji, T; Guo, L; Guragain, H; Gustafsson, H -Å; Hachiya, T; Haggerty, J S; Hahn, K I; Hamagaki, H; Hamblen, J; Han, R; Han, S Y; Hanks, J; Harper, C; Hasegawa, S; Hashimoto, K; Haslum, E; Hayano, R; He, X; Hemmick, T K; Hester, T; Hill, J C; Hollis, R S; Holzmann, W; Homma, K; Hong, B; Horaguchi, T; Hori, Y; Hornback, D; Hoshino, T; Huang, S; Ichihara, T; Ichimiya, R; Iinuma, H; Ikeda, Y; Imai, K; Imazu, Y; Inaba, M; Iordanova, A; Isenhower, D; Ishihara, M; Issah, M; Ivanischev, D; Ivanishchev, D; Iwanaga, Y; Jacak, B V; Jeon, S J; Jezghani, M; Jia, J; Jiang, X; John, D; Johnson, B M; Jones, T; Joo, E; Joo, K S; Jouan, D; Jumper, D S; Kamin, J; Kaneti, S; Kang, B H; Kang, J H; Kang, J S; Kapustinsky, J; Karatsu, K; Kasai, M; Kawall, D; Kazantsev, A V; Kempel, T; Key, J A; Khachatryan, V; Khanzadeev, A; Kihara, K; Kijima, K M; Kim, B I; Kim, C; Kim, D H; Kim, D J; Kim, E -J; Kim, H -J; Kim, M; Kim, Y -J; Kim, Y K; Kinney, E; Kiss, Á; Kistenev, E; Klatsky, J; Kleinjan, D; Kline, P; Koblesky, T; Kochenda, L; Kofarago, M; Komkov, B; Konno, M; Koster, J; Kotov, D; Král, A; Kunde, G J; Kurita, K; Kurosawa, M; Kwon, Y; Kyle, G S; Lacey, R; Lai, Y S; Lajoie, J G; Lebedev, A; Lee, D M; Lee, J; Lee, K B; Lee, K S; Lee, S H; Lee, S R; Leitch, M J; Leite, M A L; Leitgab, M; Li, X; Lim, S H; Levy, L A Linden; Liu, H; Liu, M X; Love, B; Lynch, D; Maguire, C F; Makdisi, Y I; Makek, M; Manion, A; Manko, V I; Mannel, E; Mao, Y; Masui, H; McCumber, M; McGaughey, P L; McGlinchey, D; McKinney, C; Means, N; Meles, A; Mendoza, M; Meredith, B; Miake, Y; Mibe, T; Mignerey, A C; Miki, K; Miller, A J; Milov, A; Mishra, D K; Mitchell, J T; Miyachi, Y; Miyasaka, S; Mizuno, S; Mohanty, A K; Montuenga, P; Moon, H J; Moon, T; Morino, Y; Morreale, A; Morrison, D P; Motschwiller, S; Moukhanova, T V; Murakami, T; Murata, J; Mwai, A; Nagamiya, S; Nagle, J L; Naglis, M; Nagy, M I; Nakagawa, I; Nakagomi, H; Nakamiya, Y; Nakamura, K R; Nakamura, T; Nakano, K; Nattrass, C; Netrakanti, P K; Newby, J; Nguyen, M; Nihashi, M; Niida, T; Nouicer, R; Novitzky, N; Nyanin, A S; Oakley, C; O'Brien, E; Ogilvie, C A; Oka, M; Okada, K; Koop, J D Orjuela; Oskarsson, A; Ouchida, M; Ozaki, H; Ozawa, K; Pak, R; Pantuev, V; Papavassiliou, V; Park, B H; Park, I H; Park, S; Park, S K; Pate, S F; Patel, L; Patel, M; Pei, H; Peng, J -C; Pereira, H; Perepelitsa, D V; Perera, G D N; Peressounko, D Yu; Perry, J; Petti, R; Pinkenburg, C; Pinson, R; Pisani, R P; Proissl, M; Purschke, M L; Qu, H; Rak, J; Ravinovich, I; Read, K F; Reygers, K; Reynolds, D; Riabov, V; Riabov, Y; Richardson, E; Riveli, N; Roach, D; Roche, G; Rolnick, S D; Rosati, M; Rosendahl, S S E; Rowan, Z; Rubin, J G; Sahlmueller, B; Saito, N; Sakaguchi, T; Sako, H; Samsonov, V; Sano, S; Sarsour, M; Sato, S; Sato, T; Savastio, M; Sawada, S; Schaefer, B; Schmoll, B K; Sedgwick, K; Seele, J; Seidl, R; Sen, A; Seto, R; Sett, P; Sexton, A; Sharma, D; Shein, I; Shibata, T -A; Shigaki, K; Shim, H H; Shimomura, M; Shoji, K; Shukla, P; Sickles, A; Silva, C L; Silvermyr, D; Silvestre, C; Sim, K S; Singh, B K; Singh, C P; Singh, V; Slunečka, M; Sodre, T; Soltz, R A; Sondheim, W E; Sorensen, S P; Sourikova, I V; Stankus, P W; Stenlund, E; Stepanov, M; Stoll, S P; Sugitate, T; Sukhanov, A; Sumita, T; Sun, J; Sziklai, J; Takagui, E M; Takahara, A; Taketani, A; Tanabe, R; Tanaka, Y; Taneja, S; Tanida, K; Tannenbaum, M J; Tarafdar, S; Taranenko, A; Tennant, E; Themann, H; Thomas, D; Tieulent, R; Timilsina, A; Todoroki, T; Togawa, M; Tomášek, L; Tomášek, M; Torii, H; Towell, M; Towell, R; Towell, R S; Tserruya, I; Tsuchimoto, Y; Utsunomiya, K; Vale, C; van Hecke, H W; Vargyas, M; Vazquez-Zambrano, E; Veicht, A; Velkovska, J; Vértesi, R; Virius, M; Vossen, A; Vrba, V; Vznuzdaev, E; Wang, X R; Watanabe, D; Watanabe, K; Watanabe, Y; Watanabe, Y S; Wei, F; Wei, R; Wessels, J; Whitaker, S; White, S N; Winter, D; Wolin, S; Woody, C L; Wright, R M; Wysocki, M; Xia, B; Xue, L; Yalcin, S; Yamaguchi, Y L; Yang, R; Yanovich, A; Ying, J; Yokkaichi, S; Yoo, J S; Yoon, I; You, Z; Young, G R; Younus, I; Yushmanov, I E; Zajc, W A; Zelenski, A; Zhou, S

    2014-01-01

    The PHENIX experiment at the Relativistic Heavy Ion Collider has measured low mass vector meson, $\\omega$, $\\rho$, and $\\phi$, production through the dimuon decay channel at forward rapidity ($1.2<|y|<2.2$) in $p$$+$$p$ collisions at $\\sqrt{s}=200$ GeV. The differential cross sections for these mesons are measured as a function of both $p_T$ and rapidity. We also report the integrated differential cross sections over $1

  10. Rapid characterization of dry cured ham produced following different PDOs by proton transfer reaction time of flight mass spectrometry (PTR-ToF-MS).

    Science.gov (United States)

    Del Pulgar, José Sánchez; Soukoulis, Christos; Biasioli, Franco; Cappellin, Luca; García, Carmen; Gasperi, Flavia; Granitto, Pablo; Märk, Tilmann D; Piasentier, Edi; Schuhfried, Erna

    2011-07-15

    In the present study, the recently developed proton transfer reaction time of flight mass spectrometry (PTR-ToF-MS) technique was used for the rapid characterization of dry cured hams produced according to 4 of the most important Protected Designations of Origin (PDOs): an Iberian one (Dehesa de Extremadura) and three Italian ones (Prosciutto di San Daniele, Prosciutto di Parma and Prosciutto Toscano). In total, the headspace composition and respective concentration for nine Spanish and 37 Italian dry cured ham samples were analyzed by direct injection without any pre-treatment or pre-concentration. Firstly, we show that the rapid PTR-ToF-MS fingerprinting in conjunction with chemometrics (Principal Components Analysis) indicates a good separation of the dry cured ham samples according to their production process and that it is possible to set up, using data mining methods, classification models with a high success rate in cross validation. Secondly, we exploited the higher mass resolution of the new PTR-ToF-MS, as compared with standard quadrupole based versions, for the identification of the exact sum formula of the mass spectrometric peaks providing analytical information on the observed differences. The work indicates that PTR-ToF-MS can be used as a rapid method for the identification of differences among dry cured hams produced following the indications of different PDOs and that it provides information on some of the major volatile compounds and their link with the implemented manufacturing practices such as rearing system, salting and curing process, manufacturing practices that seem to strongly affect the final volatile organic profile and thus the perceived quality of dry cured ham. Copyright © 2011 Elsevier B.V. All rights reserved.

  11. Rapid metabolic profiling of Nicotiana tabacum defence responses against Phytophthora nicotianae using direct infrared laser desorption ionization mass spectrometry and principal component analysis.

    Science.gov (United States)

    Ibáñez, Alfredo J; Scharte, Judith; Bones, Philipp; Pirkl, Alexander; Meldau, Stefan; Baldwin, Ian T; Hillenkamp, Franz; Weis, Engelbert; Dreisewerd, Klaus

    2010-06-09

    Successful defence of tobacco plants against attack from the oomycete Phytophthora nicotianae includes a type of local programmed cell death called the hypersensitive response. Complex and not completely understood signaling processes are required to mediate the development of this defence in the infected tissue. Here, we demonstrate that different families of metabolites can be monitored in small pieces of infected, mechanically-stressed, and healthy tobacco leaves using direct infrared laser desorption ionization orthogonal time-of-flight mass spectrometry. The defence response was monitored for 1 - 9 hours post infection. Infrared laser desorption ionization orthogonal time-of-flight mass spectrometry allows rapid and simultaneous detection in both negative and positive ion mode of a wide range of naturally occurring primary and secondary metabolites. An unsupervised principal component analysis was employed to identify correlations between changes in metabolite expression (obtained at different times and sample treatment conditions) and the overall defence response.A one-dimensional projection of the principal components 1 and 2 obtained from positive ion mode spectra was used to generate a Biological Response Index (BRI). The BRI obtained for each sample treatment was compared with the number of dead cells found in the respective tissue. The high correlation between these two values suggested that the BRI provides a rapid assessment of the plant response against the pathogen infection. Evaluation of the loading plots of the principal components (1 and 2) reveals a correlation among three metabolic cascades and the defence response generated in infected leaves. Analysis of selected phytohormones by liquid chromatography electrospray ionization mass spectrometry verified our findings. The described methodology allows for rapid assessment of infection-specific changes in the plant metabolism, in particular of phenolics, alkaloids, oxylipins, and carbohydrates

  12. Rapid metabolic profiling of Nicotiana tabacum defence responses against Phytophthora nicotianae using direct infrared laser desorption ionization mass spectrometry and principal component analysis

    Directory of Open Access Journals (Sweden)

    Weis Engelbert

    2010-06-01

    Full Text Available Abstract Background Successful defence of tobacco plants against attack from the oomycete Phytophthora nicotianae includes a type of local programmed cell death called the hypersensitive response. Complex and not completely understood signaling processes are required to mediate the development of this defence in the infected tissue. Here, we demonstrate that different families of metabolites can be monitored in small pieces of infected, mechanically-stressed, and healthy tobacco leaves using direct infrared laser desorption ionization orthogonal time-of-flight mass spectrometry. The defence response was monitored for 1 - 9 hours post infection. Results Infrared laser desorption ionization orthogonal time-of-flight mass spectrometry allows rapid and simultaneous detection in both negative and positive ion mode of a wide range of naturally occurring primary and secondary metabolites. An unsupervised principal component analysis was employed to identify correlations between changes in metabolite expression (obtained at different times and sample treatment conditions and the overall defence response. A one-dimensional projection of the principal components 1 and 2 obtained from positive ion mode spectra was used to generate a Biological Response Index (BRI. The BRI obtained for each sample treatment was compared with the number of dead cells found in the respective tissue. The high correlation between these two values suggested that the BRI provides a rapid assessment of the plant response against the pathogen infection. Evaluation of the loading plots of the principal components (1 and 2 reveals a correlation among three metabolic cascades and the defence response generated in infected leaves. Analysis of selected phytohormones by liquid chromatography electrospray ionization mass spectrometry verified our findings. Conclusion The described methodology allows for rapid assessment of infection-specific changes in the plant metabolism, in particular

  13. Accretion turnoff and rapid evaporation of very light secondaries in low-mass X-ray binaries

    Energy Technology Data Exchange (ETDEWEB)

    Ruderman, M.; Shaham, J.; Tavani, M.

    1989-01-01

    The illumination of companion stars in very low mass X-ray binaries by various kinds of radiation from the neighborhood of the neutron star after accretion has terminated or during accretion is considered. If a neutron star's spun-up period approaches 0.001 s, pulsar kHz radiation can quench accretion by pushing surrounding plasma away from the neutron star, and may leave the companion to be evaporated by the high-energy radiation component expected from an isolated millisecond radiopulsar. Expected accretion-powered MeV gamma-rays and e(+ or -) winds may also be effective in evaporating dwarf companions. Neutron star spin-down energy release may sustain the power in these radiation mechanisms even while accretion falls. Accretion-powered soft X-rays may speed the mass loss of highly evolved dwarf companions, particularly those with a large fraction of carbon and oxygen. 30 references.

  14. Deep Learning with Convolutional Neural Network for Differentiation of Liver Masses at Dynamic Contrast-enhanced CT: A Preliminary Study.

    Science.gov (United States)

    Yasaka, Koichiro; Akai, Hiroyuki; Abe, Osamu; Kiryu, Shigeru

    2017-10-27

    Purpose To investigate diagnostic performance by using a deep learning method with a convolutional neural network (CNN) for the differentiation of liver masses at dynamic contrast agent-enhanced computed tomography (CT). Materials and Methods This clinical retrospective study used CT image sets of liver masses over three phases (noncontrast-agent enhanced, arterial, and delayed). Masses were diagnosed according to five categories (category A, classic hepatocellular carcinomas [HCCs]; category B, malignant liver tumors other than classic and early HCCs; category C, indeterminate masses or mass-like lesions [including early HCCs and dysplastic nodules] and rare benign liver masses other than hemangiomas and cysts; category D, hemangiomas; and category E, cysts). Supervised training was performed by using 55 536 image sets obtained in 2013 (from 460 patients, 1068 sets were obtained and they were augmented by a factor of 52 [rotated, parallel-shifted, strongly enlarged, and noise-added images were generated from the original images]). The CNN was composed of six convolutional, three maximum pooling, and three fully connected layers. The CNN was tested with 100 liver mass image sets obtained in 2016 (74 men and 26 women; mean age, 66.4 years ± 10.6 [standard deviation]; mean mass size, 26.9 mm ± 25.9; 21, nine, 35, 20, and 15 liver masses for categories A, B, C, D, and E, respectively). Training and testing were performed five times. Accuracy for categorizing liver masses with CNN model and the area under receiver operating characteristic curve for differentiating categories A-B versus categories C-E were calculated. Results Median accuracy of differential diagnosis of liver masses for test data were 0.84. Median area under the receiver operating characteristic curve for differentiating categories A-B from C-E was 0.92. Conclusion Deep learning with CNN showed high diagnostic performance in differentiation of liver masses at dynamic CT. (©) RSNA, 2017 Online

  15. Rapid Species-level Identification of Salvias by Chemometric Processing of Ambient Ionisation Mass Spectrometry-derived Chemical Profiles.

    Science.gov (United States)

    Giffen, Justine E; Lesiak, Ashton D; Dane, A John; Cody, Robert B; Musah, Rabi A

    2017-01-01

    The Salvia genus contains numerous economically important plants that have horticultural, culinary and nutraceutical uses. They are often similar in appearance, making species determination difficult. Species identification of dried Salvia products is also challenging since distinguishing plant morphological features are no longer present. The development of a simple high-throughput method of analysis of fresh and dried Salvia leaves that would permit rapid species-level identification and detection of diagnostic biomarkers. Plant leaves were analysed in their native form by DART-MS without the need for any sample preparation steps. This furnished chemical fingerprints characteristic of each species. In the same experiment, in-source collision-induced dissociation was used to identify biomarkers. Biomarker presence was also independently confirmed by GC-MS. Chemometric processing of DART-MS profiles was performed by kernel discriminant analysis (KDA) and soft independent modelling of class analogy (SIMCA) to classify the fingerprints according to species. The approach was successful despite the occurrence of diurnal cycle and plant-age related chemical profile variations within species. In a single rapid experiment, the presence of essential oil biomarkers such as 3-carene, α-pinene, β-pinene, β-thujone, β-caryophyllene, camphor and borneol could be confirmed. The method was applied to rapid identification and differentiation of Salvia apiana, S. dominica, S. elegans, S. officinalis, S. farinacea and S. patens. Species-level identification of Salvia plant material could be accomplished by chemometric processing of DART-HRMS-derived chemical profiles of both fresh and dried Salvia material. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  16. [Utility of rapid on-site cytology in endoscopic ultrasonography-guided fine needle aspiration of pancreatic masses].

    Science.gov (United States)

    Furuhata, Ayako; Shirahase, Hiroyuki; Shirai, Takao; Hirata, Masahiro; Yoshizawa, Akihiko; Haga, Hironori; Nakaizumi, Akihiko

    2012-05-01

    Endoscopic ultrasonography-guided fine needle aspiration (EUS-FNA) is a safe and effective method for obtaining samples for cytological diagnosis. Pancreatic cancer is extremely serious and often extremely aggressive, so early detection and diagnosis is important. Therefore, we actively perform EUS FNA for pathological diagnosis of cancer of digestive organs, especially the pancreas. EUS-FNA was performed in 67 patients (39 male, 28 female, median age 63.3 years) from January 2007 to December 2010 in Kyoto University Hospital. To eliminate both quantitatively and qualitatively inadequate samples, we performed EUS-FNA with rapid on-site cytology. Two squash preparations of the collected cells from biopsy were retrieved. One was stained on-site with Giemsa for rapid cytology to evaluate the quantity and quality of the cell collection. If necessary, second or third trials were carried out to obtain appropriate samples for final cytology diagnosis. The other was wet-fixed and used for Papanicolaou staining. All 11 cases of inflammatory disease were diagnosed as negative on cytology. Solid-pseudopapillary neoplasm (1 case) and Endocrine neoplasms (3 cases) were correctly diagnosed on cytology. In pancreatic cancer, 49 of 52 cases (94%) were diagnosed as positive, but 3 cases (6%) were false-negative on cytology. The number of centesis for sampling was once in 21 cases, twice in 26 cases and more than twice in 20 cases. In this study of EUS-FNA, sensitivity was 94% and specificity was 100%. Results of our examination suggest that the combination of EUS-FNA and rapid on-site cytology is a highly specific and sensitive test for detection of pancreatic cancer, and may contribute to reduce excessive centesis.

  17. Direct identification of bacteria in positive blood cultures: comparison of two rapid methods, FilmArray and mass spectrometry.

    Science.gov (United States)

    Rand, Kenneth H; Delano, John P

    2014-07-01

    We evaluated the accuracy and performance of the FilmArray Direct from Positive Blood Culture system (BCID) (BioFire Diagnostics, Salt Lake City, UT, USA) and the VITEK Mass Spectrometry System (Vitek MS; bioMerieux, Durham, NC, USA) to identify bacterial isolates from 161 positive blood culture bottles. The BCID uses multiplex PCR to identify 90-95% of common isolates to the genus or species/complex level as well as mecA, Van A/B, and bla(KPC) genes in approximately 1 hour. Of 151 monomicrobic isolates, the FilmArray correctly identified 48/49 (98%) to the genus and 84/84 (100%) to the species/complex level, while 18/151 (12%) gave no identification, as expected from the database. Mass spectrometry correctly identified 142/151 (94%) monomicrobic cultures to the genus level, 137/151 (91%) to the species level, with only 8/151(5%) giving no identification. Although mass spectrometry has a much larger database, the filtration system was cumbersome in contrast to the 3-5 minutes hands-on-time for the BCID. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. Rapid MALDI-TOF Mass Spectrometry Strain Typing during a Large Outbreak of Shiga-Toxigenic Escherichia coli

    Science.gov (United States)

    Christner, Martin; Trusch, Maria; Rohde, Holger; Kwiatkowski, Marcel; Schlüter, Hartmut; Wolters, Manuel; Aepfelbacher, Martin; Hentschke, Moritz

    2014-01-01

    Background In 2011 northern Germany experienced a large outbreak of Shiga-Toxigenic Escherichia coli O104:H4. The large amount of samples sent to microbiology laboratories for epidemiological assessment highlighted the importance of fast and inexpensive typing procedures. We have therefore evaluated the applicability of a MALDI-TOF mass spectrometry based strategy for outbreak strain identification. Methods Specific peaks in the outbreak strain’s spectrum were identified by comparative analysis of archived pre-outbreak spectra that had been acquired for routine species-level identification. Proteins underlying these discriminatory peaks were identified by liquid chromatography tandem mass spectrometry and validated against publicly available databases. The resulting typing scheme was evaluated against PCR genotyping with 294 E. coli isolates from clinical samples collected during the outbreak. Results Comparative spectrum analysis revealed two characteristic peaks at m/z 6711 and m/z 10883. The underlying proteins were found to be of low prevalence among genome sequenced E. coli strains. Marker peak detection correctly classified 292 of 293 study isolates, including all 104 outbreak isolates. Conclusions MALDI-TOF mass spectrometry allowed for reliable outbreak strain identification during a large outbreak of Shiga-Toxigenic E. coli. The applied typing strategy could probably be adapted to other typing tasks and might facilitate epidemiological surveys as part of the routine pathogen identification workflow. PMID:25003758

  19. A rapid screening method to monitor expression of various recombinant proteins from prokaryotic and eukaryotic expression systems using MALDI-TOF mass spectrometry

    DEFF Research Database (Denmark)

    Jebanathirajah, J.A.; Andersen, S.; Blagoev, B.

    2002-01-01

    Rapid methods using matrix-assisted laser desorption ionization-time-of-flight mass spectrometry to monitor recombinant protein expression from various prokaryotic and eukaryotic cell culture systems were devised. Intracellular as well as secreted proteins from both induced and constitutive...... expression systems were measured and monitored from whole cells and growth media, thus providing an alternative to time-consuming traditional methods for screening and monitoring of protein expression. The methods described here involve minimal processing of samples and are therefore relevant to high...

  20. Isocratic Solid Phase Extraction-Liquid Chromatography (SPE-LC) Interfaced to High-Performance Tandem Mass Spectrometry for Rapid Protein Identification

    DEFF Research Database (Denmark)

    Hørning, Ole B; Kjeldsen, Frank; Theodorsen, Søren

    2008-01-01

    Reversed-phase liquid chromatography interfaced to electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) allows analysis of very complex peptide mixtures at great sensitivity, but it can be very time-consuming, typically using 60 min, or more, per sample analysis. We recently introduced...... the isocratic solid phase extraction-liquid chromatography (SPE-LC) technology for rapid separation ( approximately 8 min) of simple peptide samples. We now extend these studies to demonstrate the potential of SPE-LC separation in combination with a hybrid linear ion trap-Orbitrap tandem mass spectrometer...... for efficient analysis of peptide samples in proteomics research. The system performance of SPE-LC-MS/MS was evaluated in terms of sensitivity and efficiency for the analysis of tryptic peptide digests obtained from samples consisting of up to 12 standard proteins. The practical utility of the analytical setup...

  1. Rapid Discrimination of Closely Related Seed Herbs (Cumin, Caraway, and Fennel) by Direct Analysis in Real Time Mass Spectrometry (DART-MS).

    Science.gov (United States)

    Antal, Borbála; Kuki, Ákos; Nagy, Lajos; Nagy, Tibor; Zsuga, Miklós; M-Hamvas, Márta; Vasas, Gábor; Kéki, Sándor

    2016-01-01

    Direct analysis in real time mass spectrometry (DART-MS) was applied as a rapid method for the discrimination of the spices and traditional medicines cumin (Cuminum cyminum L.), caraway (Carum carvi L.), and fennel (Foeniculum vulgare Mill.). The seeds of these plants were analyzed without sample preparation by DART ion source coupled with quadrupole time-of-flight (QTOF) tandem mass spectrometry. The relatively clean DART spectra showed characteristic patterns, fingerprints, for each herb. It was found that a marker compound can be assigned to each species that can identify unambiguously these plants. Principal component analysis has also been used to analyze the DART-MS data of these seed herbs. Crispanone, carvone, and fenchone are the dominant compounds in the positive DART spectra of cumin, caraway, and fennel, respectively. Crispanone was first time identified as a constituent of cumin. Furthermore, the collision-induced dissociation (CID) behavior of the [M+NH4](+) ion of crispanone was also described.

  2. MOOC Design – Dissemination to the Masses or Facilitation of Social Learning and a Deep Approach to Learning?

    DEFF Research Database (Denmark)

    Christensen, Inger-Marie F.; Dam Laursen, Mette; Bøggild, Jacob

    2016-01-01

    This article accounts for the design of the massive open online course (MOOC) Hans Christian Andersen’s Fairy tales on FutureLearn and reports on the effectiveness of this design in terms of engaging learners in social learning and encouraging a deep approach to learning. A learning pathway...... and increased educator feedback. Course data show that that some learners use the space provided for social interaction and mutual support. A learning pathway that engages learners in discussion and progression from week to week facilitates a deep approach to learning. However, this requires more support from...

  3. Early Paleocene landbird supports rapid phylogenetic and morphological diversification of crown birds after the K-Pg mass extinction

    Science.gov (United States)

    Ksepka, Daniel T.; Stidham, Thomas A.; Williamson, Thomas E.

    2017-07-01

    Evidence is accumulating for a rapid diversification of birds following the K-Pg extinction. Recent molecular divergence dating studies suggest that birds radiated explosively during the first few million years of the Paleocene; however, fossils from this interval remain poorly represented, hindering our understanding of morphological and ecological specialization in early neoavian birds. Here we report a small fossil bird from the Nacimiento Formation of New Mexico, constrained to 62.221-62.517 Ma. This partial skeleton represents the oldest arboreal crown group bird known. Phylogenetic analyses recovered Tsidiiyazhi abini gen. et sp. nov. as a member of the Sandcoleidae, an extinct basal clade of stem mousebirds (Coliiformes). The discovery of Tsidiiyazhi pushes the minimum divergence ages of as many as nine additional major neoavian lineages into the earliest Paleocene, compressing the duration of the proposed explosive post-K-Pg radiation of modern birds into a very narrow temporal window parallel to that suggested for placental mammals. Simultaneously, Tsidiiyazhi provides evidence for the rapid morphological (and likely ecological) diversification of crown birds. Features of the foot indicate semizygodactyly (the ability to facultatively reverse the fourth pedal digit), and the arcuate arrangement of the pedal trochleae bears a striking resemblance to the conformation in owls (Strigiformes). Inclusion of fossil taxa and branch length estimates impacts ancestral state reconstructions, revealing support for the independent evolution of semizygodactyly in Coliiformes, Leptosomiformes, and Strigiformes, none of which is closely related to extant clades exhibiting full zygodactyly.

  4. Rapid imaging, detection and quantification of Giardia lamblia cysts using mobile-phone based fluorescent microscopy and machine learning.

    Science.gov (United States)

    Koydemir, Hatice Ceylan; Gorocs, Zoltan; Tseng, Derek; Cortazar, Bingen; Feng, Steve; Chan, Raymond Yan Lok; Burbano, Jordi; McLeod, Euan; Ozcan, Aydogan

    2015-03-07

    Rapid and sensitive detection of waterborne pathogens in drinkable and recreational water sources is crucial for treating and preventing the spread of water related diseases, especially in resource-limited settings. Here we present a field-portable and cost-effective platform for detection and quantification of Giardia lamblia cysts, one of the most common waterborne parasites, which has a thick cell wall that makes it resistant to most water disinfection techniques including chlorination. The platform consists of a smartphone coupled with an opto-mechanical attachment weighing ~205 g, which utilizes a hand-held fluorescence microscope design aligned with the camera unit of the smartphone to image custom-designed disposable water sample cassettes. Each sample cassette is composed of absorbent pads and mechanical filter membranes; a membrane with 8 μm pore size is used as a porous spacing layer to prevent the backflow of particles to the upper membrane, while the top membrane with 5 μm pore size is used to capture the individual Giardia cysts that are fluorescently labeled. A fluorescence image of the filter surface (field-of-view: ~0.8 cm(2)) is captured and wirelessly transmitted via the mobile-phone to our servers for rapid processing using a machine learning algorithm that is trained on statistical features of Giardia cysts to automatically detect and count the cysts captured on the membrane. The results are then transmitted back to the mobile-phone in less than 2 minutes and are displayed through a smart application running on the phone. This mobile platform, along with our custom-developed sample preparation protocol, enables analysis of large volumes of water (e.g., 10-20 mL) for automated detection and enumeration of Giardia cysts in ~1 hour, including all the steps of sample preparation and analysis. We evaluated the performance of this approach using flow-cytometer-enumerated Giardia-contaminated water samples, demonstrating an average cyst capture

  5. Solid-phase microextraction low temperature plasma mass spectrometry for the direct and rapid analysis of chemical warfare simulants in complex mixtures.

    Science.gov (United States)

    Dumlao, Morphy C; Jeffress, Laura E; Gooding, J Justin; Donald, William A

    2016-06-21

    Solid-phase microextraction (SPME) is directly integrated with low temperature plasma ionisation mass spectrometry to rapidly detect organophosphate chemical warfare agent simulants and their hydrolysis products in chemical mixtures, including urine. In this sampling and ionization method, the fibre serves: (i) to extract molecules from their native environment, and (ii) as the ionization electrode that is used to desorb and ionize molecules directly from the SPME surface. By use of a custom fabricated SPME fibre consisting of a stainless steel needle coated with a Linde Type A (LTA) zeolitic microporous material and low temperature plasma mass spectrometry, protonated dimethyl methylphosphonate (DMMP), diethyl ethylphosphonate (DEEP) and pinacolyl methylphosphonic acid (PinMPA) can be detected at less than 100 ppb directly in water and urine. Organophosphates were not readily detected by this approach using an uncoated needle in negative control experiments. The use of the LTA coating significantly outperformed the use of a high alumina Zeolite Socony Mobil-5 (ZSM-5) coating of comparable thickness that is significantly less polar than LTA. By conditioning the LTA probe by immersion in an aqueous CuSO4 solution, the ion abundance for protonated DMMP increased by more than 300% compared to that obtained without any conditioning. Sample recovery values were between 96 and 100% for each analyte. The detection of chemical warfare agent analogues and hydrolysis products required less than 2 min per sample. A key advantage of this sampling and ionization method is that analyte ions can be directly and rapidly sampled from chemical mixtures, such as urine and seawater, without sample preparation or chromatography for sensitive detection by mass spectrometry. This ion source should prove beneficial for portable mass spectrometry applications because relatively low detection limits can be obtained without the use of compressed gases, fluid pumps, and lasers. Moreover, the

  6. Fostering Scientific and Numerate Practices in Journalism to Support Rapid Public Learning

    Directory of Open Access Journals (Sweden)

    Louise Yarnall

    2017-01-01

    Full Text Available Journalism has the potential––and arguably the mandate––to expand public understanding of societally important phenomena. However, some methods for more effectively educating the public have been persistently underutilized: in particular, embedding informative numerical rates and efficient scientific explanations in news reports. In the current era of disrupting and downsizing the news business, the challenges to using such methods have only increased. To address this problem, this article seeks to (a raise awareness about the psychological reasons that help explain why it is crucial to use such elements in news reports, and (b exhibit some methods for doing so that require modest effort. Building on a review of relevant psychological literatures, principles, and existing reporting methods, we describe findings from a series of cognitive-scientific studies that demonstrate how using key––and relatively minimal––scientific and numerical elements can enhance public learning from news reports. We conclude by also describing curricula and resources designed to help journalists and bloggers use these methods.

  7. Rapid Screening and Identification of Daidzein Metabolites in Rats Based on UHPLC-LTQ-Orbitrap Mass Spectrometry Coupled with Data-Mining Technologies

    Directory of Open Access Journals (Sweden)

    Wenjing Zhao

    2018-01-01

    Full Text Available Daidzein, the main bioactive soy isoflavone in Nature, has been found to possess many biological functions. It has been investigated in particular as a phytoestrogen owing to the similarity of its structure with that of the human hormone estrogen. Due to the lack of comprehensive studies on daidzein metabolism, further research is still required to clarify its in vivo metabolic fate and intermediate processes. In this study, an efficient strategy was established using UHPLC-LTQ-Orbitrap mass spectrometry to profile the metabolism of daidzein in rats. Meanwhile, multiple data-mining methods including high-resolution extracted ion chromatogram (HREIC, multiple mass defect filtering (MMDF, neutral loss fragment (NLF, and diagnostic product ion (DPI were utilized to investigate daidzein metabolites from the HR-ESI-MS1 to ESI-MSn stage in both positive and negative ion modes. Consequently, 59 metabolites, including prototype compounds, were positively or tentatively elucidated based on reference standards, accurate mass measurements, mass fragmentation behaviors, chromatographic retention times, and corresponding calculated ClogP values. As a result, dehydration, hydrogenation, methylation, dimethylation, glucuronidation, glucosylation, sulfonation, ring-cleavage, and their composite reactions were ascertained to interpret its in vivo biotransformation. Overall, our results not only revealed the potential pharmacodynamics forms of daidzein, but also aid in establishing a practical strategy for rapid screening and identifying metabolites of natural compounds.

  8. Rapid Screening and Identification of Daidzein Metabolites in Rats Based on UHPLC-LTQ-Orbitrap Mass Spectrometry Coupled with Data-Mining Technologies.

    Science.gov (United States)

    Zhao, Wenjing; Shang, Zhanpeng; Li, Qinqing; Huang, Moran; He, Wenbin; Wang, Zhibin; Zhang, Jiayu

    2018-01-12

    Daidzein, the main bioactive soy isoflavone in Nature, has been found to possess many biological functions. It has been investigated in particular as a phytoestrogen owing to the similarity of its structure with that of the human hormone estrogen. Due to the lack of comprehensive studies on daidzein metabolism, further research is still required to clarify its in vivo metabolic fate and intermediate processes. In this study, an efficient strategy was established using UHPLC-LTQ-Orbitrap mass spectrometry to profile the metabolism of daidzein in rats. Meanwhile, multiple data-mining methods including high-resolution extracted ion chromatogram (HREIC), multiple mass defect filtering (MMDF), neutral loss fragment (NLF), and diagnostic product ion (DPI) were utilized to investigate daidzein metabolites from the HR-ESI-MS¹ to ESI-MSn stage in both positive and negative ion modes. Consequently, 59 metabolites, including prototype compounds, were positively or tentatively elucidated based on reference standards, accurate mass measurements, mass fragmentation behaviors, chromatographic retention times, and corresponding calculated ClogP values. As a result, dehydration, hydrogenation, methylation, dimethylation, glucuronidation, glucosylation, sulfonation, ring-cleavage, and their composite reactions were ascertained to interpret its in vivo biotransformation. Overall, our results not only revealed the potential pharmacodynamics forms of daidzein, but also aid in establishing a practical strategy for rapid screening and identifying metabolites of natural compounds.

  9. Detection and mapping of Cannabinoids in single hair samples through rapid derivatization- Matrix-Assisted Laser Desorption Ionization Mass Spectrometry

    OpenAIRE

    Beasley, Emma; Francese, Simona; Bassindale, Thomas

    2016-01-01

    The sample preparation method reported in this work has permitted for the first time the application of Matrix Assisted Laser Desorption Ionization Mass Spectrometry Profiling and Imaging (MALDI-MSP and MALDI-MSI) for the detection and mapping of cannabinoids in a single hair sample. MALDI-MSI analysis of hair samples has recently been suggested as an alternative technique to traditional methods of GC-MS and LC-MS due to simpler sample preparation, the ability to detect a narrower time frame ...

  10. Surprising Rapid Collapse of Sirius B from Red Giant to White Dwarf Through Mass Transfer to Sirius a

    Science.gov (United States)

    Yousef, Shahinaz; Ali, Ola

    2013-03-01

    Sirius was observed in antiquity as a red star. In his famous astronomy textbook the Almagest written 140 AD, Ptolemy described the star Sirius as fiery red. He curiously depicted it as one of six red-colored stars. The other five are class M and K stars, such as Arcturus and Betelgeuse. Apparent confirmation in ancient Greek and Roman sources are found and Sirius was also reported red in Europe about 1400 years ago. Sirius must have changed to a white dwarf in the night of Ascension. The star chapter in the Quran started with "by the star as it collapsed (1) your companion have not gone astray nor being misled (2), and in verse 49 which is the rotation period of the companion Sirius B around Sirius A, it is said" He is the Lord of Sirius (49). If Sirius actually was red what could have caused it to change into the brilliant bluish-white star we see today? What the naked eye perceives as a single star is actually a binary star system, consisting of a white main sequence star of spectral type A1V, termed Sirius A, and a faint white dwarf companion of spectral type DA2, termed Sirius B. The red color indicates that the star seen then was a red giant. It looks that what they have seen in antiquity was Sirius B which was then a red giant and it collapsed to form a white dwarf. Since there is no evidence of a planetary nebula, then the red Sirius paradox can be solved in terms of stellar evolution with mass transfer. Sirius B was the most massive star which evolved to a red giant and filled the Roche lobe. Mass transfer to Sirius A occurred through the Lagrangian point. Sirius A then became more massive while Sirius B lost mass and shrank. Sirius B then collapsed abruptly into a white dwarf. In the case of Algol, Ptolmy observed it as white star but it was red at the time of El sufi. At present it is white. The rate of mass transfer from Sirius B to Sirius A, and from Algol B to A is estimated from observational data of colour change from red to bullish white to be 0

  11. Rapid and sensitive liquid chromatography-tandem mass spectrometry method for the quantitation of levodropropizine in human plasma.

    Science.gov (United States)

    Tang, Yunbiao; Zhao, Limei; Wang, Yingwu; Fawcett, J Paul; Gu, Jingkai

    2005-05-05

    A rapid and sensitive LC-MS-MS method for quantifying levodropropizine in human plasma after oral administration of a single-dose (60 mg/day) was developed and validated. The sample preparation used liquid-liquid extraction with a mixture of dichloromethane-diethyl ether (2:3, v/v) in a basic environment. The retention time of levodropropizne and zolmitriptan (used as internal standard) was 1.6 and 1.4 min, respectively. The assay was linear over the range 0.25-500 ng/mL with a LOQ of 0.25 ng/mL. The intra- and inter-day precision were levodropropizine concentration profile in human plasma was determined.

  12. Rapid and sensitive hormonal profiling of complex plant samples by liquid chromatography coupled to electrospray ionization tandem mass spectrometry

    Directory of Open Access Journals (Sweden)

    Müller Maren

    2011-11-01

    Full Text Available Abstract Background Plant hormones play a pivotal role in several physiological processes during a plant's life cycle, from germination to senescence, and the determination of endogenous concentrations of hormones is essential to elucidate the role of a particular hormone in any physiological process. Availability of a sensitive and rapid method to quantify multiple classes of hormones simultaneously will greatly facilitate the investigation of signaling networks in controlling specific developmental pathways and physiological responses. Due to the presence of hormones at very low concentrations in plant tissues (10-9 M to 10-6 M and their different chemistries, the development of a high-throughput and comprehensive method for the determination of hormones is challenging. Results The present work reports a rapid, specific and sensitive method using ultrahigh-performance liquid chromatography coupled to electrospray ionization tandem spectrometry (UPLC/ESI-MS/MS to analyze quantitatively the major hormones found in plant tissues within six minutes, including auxins, cytokinins, gibberellins, abscisic acid, 1-amino-cyclopropane-1-carboxyic acid (the ethylene precursor, jasmonic acid and salicylic acid. Sample preparation, extraction procedures and UPLC-MS/MS conditions were optimized for the determination of all plant hormones and are summarized in a schematic extraction diagram for the analysis of small amounts of plant material without time-consuming additional steps such as purification, sample drying or re-suspension. Conclusions This new method is applicable to the analysis of dynamic changes in endogenous concentrations of hormones to study plant developmental processes or plant responses to biotic and abiotic stresses in complex tissues. An example is shown in which a hormone profiling is obtained from leaves of plants exposed to salt stress in the aromatic plant, Rosmarinus officinalis.

  13. Equipment and methods for rapid analysis of PWO full size scintillation crystals radiation hardness at mass production

    CERN Document Server

    Annenkov, A N; Drobychev, G Yu; Fedorov, A; Ivankin, P; Korzhik, M V; Lecoq, P; Ligun, V; Lopatik, A; Matveev, L; Missevitch, O V; Zouevski, R F; Peigneux, J P; Sigovski, A

    2000-01-01

    This year an extensive R&D on lead tungstate crystals has entered into the pre-production phase at the Bogoroditsk Techno-Chemical Plant (BTCP). Laboratory small-scale PWO crystal growth technology, which has been tuned and optimised over the last years, is transforming now into an industrial technology of mass production. This mass production technology is based on a set of methods and instrumentation for crystal growth, machining, crystal quality control and certification. According to the specification on lead tungstate pre-production crystals, one of the most important categories of tolerance is the radiation hardness. Control of the PWO radiation hardness at the pre-production phase requires reliability and an easy to use measuring tool with a high productivity. A semi- automatic spectrometric setup for PWO radiation hardness monitoring has been developed and tested at the X5 CERN irradiation facility. After final crosschecks the setup was set into operation at the BTCP. Together with several other m...

  14. A gas/liquid chromatographic-mass spectrometric method for the rapid screening of 250 pesticides in aqueous matrices

    Energy Technology Data Exchange (ETDEWEB)

    Chandramouli, B.; Harvan, D.; Brittain, S.; Hass, R. [Eno River Labs, LLC. Durham, NC (United States)

    2004-09-15

    Pesticide residues in food present a potentially serious and significant cause for concern. Many pesticides have been associated with significant health effects to the nervous and endocrine systems and some have been deemed carcinogenic. There are many well-established techniques for pesticide analysis. However, commercial pesticide methods have traditionally only been available for specific pesticide families, such as chlorinated pesticides or herbicides, and at detection limits ranging from 0.05 ppb to 1 ppm in aqueous matrices. Techniques that can quickly screen for the presence/absence of pesticide residues in food matrices are critical in ensuring the safety of food and water. This paper outlines a combined Gas Chromatographic-High Resolution Mass Spectrometric (GC-HRMS) and Liquid Chromatographic Tandem Mass Spectrometric (LC-MS/MS) screening assay for 250 pesticides that was developed for use in water, and soda samples at screening levels ranging from 0.1-5 ppb. The pesticides selected have been identified by the European Union as being of concern and the target of possible legislation. The list encompasses a variety of pesticide classes and compound groupings.

  15. Rapid disaster victim identification in mass fatality incidents: decision-support tool to facilitate human remains identification.

    Science.gov (United States)

    de Cosmo, Sergio; Barbera, Joseph A

    2012-10-01

    A quantitative decision-support tool (DST), using a combination of selected human physical attributes as identification elements, was developed to facilitate body identification in mass fatality incidents, particularly in settings with limited availability of technological resources and forensic expertise. To construct the DST, the external biological attributes of interest were first selected. A process was then developed to guide collection of the selected categories of attributes and record them into objective antemortem (AM) and postmortem (PM) records. Finally, a framework for assessing the similarity between confronting PM-AM attribute records was established. The DST evaluates the similarities between each set of like attributes in the AM and PM records being compared. It then computes an overall similarity score for each evaluated AM record that was compared to a selected PM record. The AM record with the highest score represents the highest probable match, with the PM file selected for the comparison. Multiple simulations across a range of mass fatality situations demonstrated the effectiveness of the DST in the experimental setting. The developed DST may provide authorities with a method for expediting body identification without completely eliminating any missing person file from consideration. Under specific circumstances, this method may reduce the need for technologically sophisticated forensic identification techniques (eg, dental records, fingerprints, and DNA). At a minimum, it should facilitate the efficiency of the current technological matching process.

  16. Applying characteristic fragment filtering for rapid detection and identification of ingredients in rhubarb by HPLC coupled with linear ion trap-Orbitrap mass spectrometry.

    Science.gov (United States)

    Wang, Qing; Lu, Zhiwei; Zhang, Li; Zhang, Qingqing; Wang, Meiling; Zhao, Huizhen; Liu, Yuehong; Fu, Shuang; Huang, Zhenghai; Xie, Ziye; Yu, Honghong; Zhang, Zhixin; Gao, Xiaoyan

    2017-07-01

    Chemical characteristic fragment filtering in MSn chromatograms was proposed to detect and identify the components in rhubarb rapidly using high-performance liquid chromatography coupled with linear ion trap-Orbitrap mass spectrometry. Characteristic fragments consist of diagnostic ions and neutral loss fragments. Characteristic fragment filtering is a postacquisition data mining method for the targeted screening of groups with specific structures, including three steps: first, in order to comprehensively summarize characteristic fragments for global identification of the ingredients in rhubarb, representative authentic standards of dominant chemical categories contained in rhubarb were chosen, from which fragmentation rules and a characteristic fragments schedule were proposed; second, characteristic fragment filtering was used to rapidly recognize analogous skeletons; finally, combined with retention time, accurate mass, characteristic fragments, and previous literature, the structures of the filtered compounds were identified or tentatively characterized. As a result, a total of 271 compounds were detected and identified in rhubarb, including 34 anthraquinones, 83 anthrones, 46 tannins, 17 stilbenes, 24 phenylbutanones, 26 acylglucosides, 26 chromones, and 15 other compounds, 69 of which are potentially new compounds. The proposed characteristic fragment filtering strategy would be a reference for the large-scale detection and identification of the ingredients of herbal medicines. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Diagnosis of congenital adrenal hyperplasia by rapid determination of 17alpha-hydroxyprogesterone in dried blood spots by gas chromatography/mass spectrometry following microwave-assisted silylation.

    Science.gov (United States)

    Deng, Chunhui; Ji, Jie; Zhang, Lijuan; Zhang, Xiangmin

    2005-01-01

    17alpha-Hydroxyprogesterone (17OHP) is considered to be the biomarker of congential adrenal hyperplasia (CAH). Screening for CAH in newborns by measuring levels of the biomarker of 17OHP has become routine. In the work, a rapid, simple and sensitive technique was developed for the diagnosis of neonatal CAH by the quantitative analysis of 17OHP in neonatal blood spots. The technique was based on microwave-assisted silylation (MAS) followed by gas chromatography/mass spectrometry (GC/MS). In the method, fast derivatization of 17OHP with N,O-bis(trimethylsilyl)trifluoroacetamide was performed by using microwave irradiation, and the trimethylsilyl derivative thus formed was analyzed by GC/MS. The results of the experiment indicate that MAS followed by GC/MS analysis is a rapid, simple and sensitive method for the determination of 17OHP in blood samples. The proposed technique has been shown to have potential as a powerful tool for the rapid diagnosis of neonatal CAH. (c) 2005 John Wiley & Sons, Ltd.

  18. Simultaneous detection of perchlorate and bromate using rapid high-performance ion exchange chromatography-tandem mass spectrometry and perchlorate removal in drinking water.

    Science.gov (United States)

    West, Danielle M; Mu, Ruipu; Gamagedara, Sanjeewa; Ma, Yinfa; Adams, Craig; Eichholz, Todd; Burken, Joel G; Shi, Honglan

    2015-06-01

    Perchlorate and bromate occurrence in drinking water causes health concerns due to their effects on thyroid function and carcinogenicity, respectively. The purpose of this study was threefold: (1) to advance a sensitive method for simultaneous rapid detection of perchlorate and bromate in drinking water system, (2) to systematically study the occurrence of these two contaminants in Missouri drinking water treatment systems, and (3) to examine effective sorbents for minimizing perchlorate in drinking water. A rapid high-performance ion exchange chromatography-tandem mass spectrometry (HPIC-MS/MS) method was advanced for simultaneous detection of perchlorate and bromate in drinking water. The HPIC-MS/MS method was rapid, required no preconcentration of the water samples, and had detection limits for perchlorate and bromate of 0.04 and 0.01 μg/L, respectively. The method was applied to determine perchlorate and bromate concentrations in total of 23 selected Missouri drinking water treatment systems during differing seasons. The water systems selected include different source waters: groundwater, lake water, river water, and groundwater influenced by surface water. The concentrations of perchlorate and bromate were lower than or near to method detection limits in most of the drinking water samples monitored. The removal of perchlorate by various adsorbents was studied. A cationic organoclay (TC-99) exhibited effective removal of perchlorate from drinking water matrices.

  19. Rapid detection of GM1 ganglioside in cerebrospinal fluid in dogs with GM1 gangliosidosis using matrix-assisted laser desorption ionization time-of-flight mass spectrometry.

    Science.gov (United States)

    Satoh, Hiroyuki; Yamauchi, Toyofumi; Yamasaki, Masahiro; Maede, Yoshimitsu; Yabuki, Akira; Chang, Hye-Sook; Asanuma, Taketoshi; Yamato, Osamu

    2011-11-01

    The concentration of GM1 (monosialotetrahexosyl ganglioside) in cerebrospinal fluid (CSF) is markedly increased in dogs with GM1 gangliosidosis due to GM1 accumulation in the central nervous system and leakage to the CSF. The present study established a rapid and simple method for detection of accumulated GM1 in the CSF in dogs with GM1 gangliosidosis using matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI TOF MS) and discusses the usefulness of this method for the rapid diagnosis and/or high-risk screening of this disease in domestic animals. Cerebrospinal fluid was collected from normal dogs and 4- to 11-month-old Shiba dogs with GM1 gangliosidosis. The MALDI TOF MS analysis was carried out in combination with a special sample plate and a simple desalting step on the plate. Specific signs of GM1 could be detected in the standard GM1 solutions at concentrations of 50 nmol/l or more. The signs were also clearly detected in CSF (131-618 nmol/l) in affected dogs, but not in normal canine CSF (12 ± 5 nmol/l, mean ± standard deviation). The results demonstrated that MALDI TOF MS can detect GM1 accumulated in canine CSF even in the early stage of the disease. In conclusion, the rapid detection of increased CSF GM1 using MALDI TOF MS is a useful method for diagnosis and/or screening for canine GM1 gangliosidosis.

  20. Rapid and simultaneous in situ assessment of aflatoxins and stilbenes using silica plate imprinting mass spectrometry imaging.

    Directory of Open Access Journals (Sweden)

    Diogo N de Oliveira

    Full Text Available A fast and direct combination of techniques for simultaneous mycotoxin and phytoalexin identification in peanut skin and kernel is described. Silica Plate Imprinting Laser Desorption/Ionization Mass Spectrometry Imaging (SPILDI-MSI is a powerful technique that exhibits great advantages, such as solvent-free and matrix-free characteristics, as well as no sample preparation or separation steps. It also permits accurate identification of mycotoxins and phytoalexins with unique fingerprint profiles in just a few seconds. Results are expressed as chemical images of the 4 identified types of aflatoxins (B1, B2, G1 and G2 and a stilbenoid (resveratrol. Also, SPILDI-MSI allows the comparison between the spatial distribution of aflatoxins and resveratrol found in kernel and skin. This novel application has proven to be useful for instantaneous qualitative assessment of aflatoxins and stilbenoids both in the peanut skin and kernel and offers precise tracking of fungal contamination in nuts and other foodstuffs.

  1. A novel method to rapidly distinguish the geographical origin of traditional fermented-salted vegetables by mass fingerprinting

    Science.gov (United States)

    Yoon, So-Ra; Kim, Sung Hyun; Lee, Hae-Won

    2017-01-01

    The geographical origin of kimchi is of interest to consumers and producers because the prices of commercial kimchi products can vary significantly according to the geographical origin. Hence, social issues related to the geographical origin of kimchi in Korea have emerged as a major problem. In this study, the geographical origin of kimchi was determined by comparing the mass fingerprints obtained for Korean and Chinese kimchi samples by MALDI-TOF MS with multivariate analysis. The results obtained herein provide an accurate, powerful tool to clearly discriminate kimchi samples based on their geographical origin within a short time and to ensure food authenticity, which is of significance in the kimchi industry. Furthermore, our MALDI-TOF MS method could be applied to determining the geographical origin of other fermented-salted vegetables at a reduced cost in shorter times. PMID:29149220

  2. A novel method to rapidly distinguish the geographical origin of traditional fermented-salted vegetables by mass fingerprinting.

    Directory of Open Access Journals (Sweden)

    So-Ra Yoon

    Full Text Available The geographical origin of kimchi is of interest to consumers and producers because the prices of commercial kimchi products can vary significantly according to the geographical origin. Hence, social issues related to the geographical origin of kimchi in Korea have emerged as a major problem. In this study, the geographical origin of kimchi was determined by comparing the mass fingerprints obtained for Korean and Chinese kimchi samples by MALDI-TOF MS with multivariate analysis. The results obtained herein provide an accurate, powerful tool to clearly discriminate kimchi samples based on their geographical origin within a short time and to ensure food authenticity, which is of significance in the kimchi industry. Furthermore, our MALDI-TOF MS method could be applied to determining the geographical origin of other fermented-salted vegetables at a reduced cost in shorter times.

  3. Rapid discrimination of environmental Vibrio by matrix-assisted laser desorption ionization time-of-flight mass spectrometry.

    Science.gov (United States)

    Eddabra, Rkia; Prévost, Gilles; Scheftel, Jean-Michel

    2012-04-20

    The aim of this study was to discriminate 30 Vibrio strains isolated from two wastewater treatment plants from Agadir, Morocco by two molecular typing methods, pulsed-field gel electrophoresis (PFGE) and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Out of the 30 strains of Vibrio examined in this study, 5 isolates could not be typed by PFGE and consistently appeared as a smear on the gel. In general, high genetic biodiversity among the Vibrio strains was found regardless to the isolation source. The results of MALDI TOF analysis show a high congruence of strain grouping demonstrating the accuracy and reliability of MALDI-TOF MS. Copyright © 2011 Elsevier GmbH. All rights reserved.

  4. Rapid and simultaneous in situ assessment of aflatoxins and stilbenes using silica plate imprinting mass spectrometry imaging.

    Science.gov (United States)

    de Oliveira, Diogo N; Ferreira, Mônica S; Catharino, Rodrigo R

    2014-01-01

    A fast and direct combination of techniques for simultaneous mycotoxin and phytoalexin identification in peanut skin and kernel is described. Silica Plate Imprinting Laser Desorption/Ionization Mass Spectrometry Imaging (SPILDI-MSI) is a powerful technique that exhibits great advantages, such as solvent-free and matrix-free characteristics, as well as no sample preparation or separation steps. It also permits accurate identification of mycotoxins and phytoalexins with unique fingerprint profiles in just a few seconds. Results are expressed as chemical images of the 4 identified types of aflatoxins (B1, B2, G1 and G2) and a stilbenoid (resveratrol). Also, SPILDI-MSI allows the comparison between the spatial distribution of aflatoxins and resveratrol found in kernel and skin. This novel application has proven to be useful for instantaneous qualitative assessment of aflatoxins and stilbenoids both in the peanut skin and kernel and offers precise tracking of fungal contamination in nuts and other foodstuffs.

  5. Trypsin immobilization on an ethylenediamine-based monolithic minidisk for rapid on-line peptide mass fingerprinting studies.

    Science.gov (United States)

    Nicoli, R; Rudaz, S; Stella, C; Veuthey, J-L

    2009-03-27

    The aim of this work was to develop a trypsin-based micro-immobilized enzyme reactor prepared on a monolithic ethylenediamine BIA Separations CIM (convective interaction media) minidisk. The micro-immobilized enzyme reactor (IMER) was integrated in a liquid chromatography system hyphenated to electrospray ionization tandem mass spectrometry to carry out on-line protein digestion and identification. The performance of this IMER was compared with that obtained using a previously developed bioreactor prepared on a conventional CIM ethylenediamine disk and with that of the commercially available Poroszyme immobilized trypsin cartridge. In this work, we showed how different proteins were identified with good recoveries using a digestion time of 10 min only.

  6. Rapid simultaneous determination of organophosphorus pesticides in human serum and urine by liquid chromatography-mass spectrometry

    Directory of Open Access Journals (Sweden)

    Zlatković Milica

    2010-01-01

    Full Text Available Background/Aim. Analysis of organophosphosphorus compounds and their metabolites in a biological material includes the use of numerous methods, covering both preparation of samples for analysis and their identification that is considered to be very complex. Low concentrations monitoring requires implementation of highly sensitive analytical techniques. The aim of this study was to develop and validate an original and sensitive method for the detection and quantitation of organophosphorus pesticides (dimethoate, diazinon, malathion and malaoxon in human biological matrices (serum, urine. Methods. This method was based on a solid-phase extraction procedure, a chromatographic separation using an ACQUITY UPLC ® HSST3 column and mass spectrometric detection in the positve ion mode. Mobile phase: was consited of Solvent A (5 mM ammonium formate pH 3.0 and Solvent B (0.1% acetic formate in methanol, in a linear gradient (constant flow-rate 0.3 mL/min. Results. The standard curve was linear in the range of 0.05-5.00 mg/L for malathion and malaoxon, 0.10-5.00 mg/L for dimethoate and 0.05-2.50 mg/L for diazinon. The correlation coefficient was r ≥ 0.99. Extraction recoveries were satisfactory and ranged between 90-99%. The limits of detection (LOD was between 0.007- 0.07 mg/L and the limits of quantitation (LOQ ranged between 0.022-0.085 mg/L. Intra- and interassay precision and accuracy were satisfactory for all of the pesticides analyzed. Conclusion. The method of liquid chromatography - mass spectrometry is simple, accurate, and useful for the determination of organophosphorus pesticides in both clinical and forensic toxicology.

  7. Rapid and reliable steroid hormone profiling in Tursiops truncatus blubber using liquid chromatography tandem mass spectrometry (LC-MS/MS).

    Science.gov (United States)

    Boggs, Ashley S P; Schock, Tracey B; Schwacke, Lori H; Galligan, Thomas M; Morey, Jeanine S; McFee, Wayne E; Kucklick, John R

    2017-08-01

    Monitoring of marine mammal steroid hormone status using matrices alternative to blood is desirable due to the ability to remotely collect samples, which minimizes stress to the animal. However, measurement techniques in alternative matrices such as blubber described to date are limited in the number and types of hormones measured. Therefore, a new method using bead homogenization to QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) extraction, C18 post extraction cleanup and analysis by liquid chromatography tandem mass spectrometry (LC-MS/MS) was developed and applied to the measurement of hormone suites in bottlenose dolphin blubber. Validations were conducted in blubber from fresh dead stranded bottlenose dolphin. The final method consisting of two LC separations and garnet bead homogenization was tested for extraction efficiencies. Steroids were separated using a biphenyl column for reproductive hormones and C18 column for corticosteroids. Three hormones previously noted in blubber, testosterone, progesterone, and cortisol, were quantified in addition to previously unmeasured androstenedione, 17-hydroxyprogesterone, 11-deoxycortisol, 11-deoxycorticosterone, and cortisone in a single sample (0.4 g blubber). Extraction efficiencies of all hormones from blubber ranged from 84% to 112% and all RSDs were comparable to those reported using immunoassay methods (< 15%). The method was successfully applied to remote biopsied blubber samples to measure baseline hormone concentrations. Through this method, increased coverage of steroid hormone pathways from a single remotely collected sample potentially enhances the ability to interpret biological phenomena such as reproduction and stress in wild dolphin populations. Graphical abstract The steroid hormone profile is quantifiable from a single sample of bottlenose dolphin blubber using liquid chromatography tandem mass spectrometry. This profile can be applied to remotely collected dart biopsies and be used to

  8. Rapid identification of siderophores by combined thin-layer chromatography/matrix-assisted laser desorption/ionization mass spectrometry.

    Science.gov (United States)

    Hayen, Heiko; Volmer, Dietrich A

    2005-01-01

    The investigation of a combined thin-layer chromatography/matrix-assisted laser desorption/ionization mass spectrometry (TLC/MALDI-MS) method for the analysis of siderophores from microbial samples is described. The investigated siderophores were enterobactin, ferrioxamine B, ferrichrome, ferrirhodin, rhodotorulic acid and coprogen. Solid-phase extraction was employed to recover the siderophores from the microbial samples. After visualization of the spots via spraying with ferric chloride or chrome azurol sulfonate assay solution, the MALDI matrix was applied to the gel surface. Several TLC/MALDI experimental parameters were optimized, such as type and concentration of MALDI matrix, as well as the type and composition of solvent to facilitate analyte transport from the inside of the TLC gel to the surface. The impact of these parameters on sensitivity, precision and ion formation of the various siderophores was studied. The detection limits for the investigated siderophores were in the range 1-4 pmol. These values were about 4-24 times higher than the detection limits obtained directly from stainless steel MALDI targets. The differences were most likely due to incomplete transport of the 'trapped' analyte molecules from the deeper layers of the TLC gel to the surface and into the matrix layer. In addition, chromatographic band broadening spread the analyte further in TLC as compared with the steel plates, resulting in less analyte per surface area. The identification of the siderophores was aided by concurrently applying a Ga(III) nitrate solution to the TLC plate during the visualization step. The resulting formation of Ga(III) complexes lead to distinctive (69)Ga/(71)Ga isotope patterns in the mass spectra. The versatility of the TLC/MALDI-MS assay was demonstrated by using it to analyze siderophores in a Pseudomonas aeruginosa sample. An iron-binding compound was identified in the sample, namely pyochelin (2-(2-o-hydroxyphenyl-2-thiazolin-4-yl)-3

  9. Rapid X-ray variability properties during the unusual very hard state in neutron-star low-mass X-ray binaries

    Science.gov (United States)

    Wijnands, R.; Parikh, A. S.; Altamirano, D.; Homan, J.; Degenaar, N.

    2017-11-01

    Here, we study the rapid X-ray variability (using XMM-Newton observations) of three neutron-star low-mass X-ray binaries (1RXS J180408.9-342058, EXO 1745-248 and IGR J18245-2452) during their recently proposed very hard spectral state. All our systems exhibit a strong to very strong noise component in their power density spectra (rms amplitudes ranging from 34 per cent to 102 per cent) with very low characteristic frequencies (as low as 0.01 Hz). These properties are more extreme than what is commonly observed in the canonical hard state of neutron-star low-mass X-ray binaries observed at X-ray luminosities similar to those we observe from our sources. This suggests that indeed the very hard state is a spectral-timing state distinct from the hard state, although we argue that the variability behaviour of IGR J18245-2452 is very extreme and possibly this source was in a very unusual state. We also compare our results with the rapid X-ray variability of the accreting millisecond X-ray pulsars IGR J00291+5934 and Swift J0911.9-6452 (also using XMM-Newton data) for which previously similar variability phenomena were observed. Although their energy spectra (as observed using the Swift X-ray telescope) were not necessarily as hard (i.e. for Swift J0911.9-6452) as for our other three sources, we conclude that likely both sources were also in very similar state during their XMM-Newton observations. This suggests that different sources that are found in this new state might exhibit different spectral hardness and one has to study both the spectral and the rapid variability to identify this unusual state.

  10. Rapid, non-destructive selection of peanuts for high aflatoxin content by soaking and tandem mass spectrometry.

    Science.gov (United States)

    Schatzki, Thomas F; Haddon, William F

    2002-05-08

    Peanut lots are subject to aflatoxin levels high enough to cause concern to health agencies and trade channels. A possible solution would be to mechanically sort out high aflatoxin nuts from the process stream. Only highly contaminated nuts would need to be removed. However, there exists at present no sorting mechanism which meets commercial needs of adequate reduction and product preservation. To build such a sorter requires knowledge of the properties that can be used for sorting. The first step in the design is to select on the order of one hundred undamaged contaminated nuts which can be compared with noncontaminated ones. Because contaminated nuts are rare, a very large number of nuts needs to be examined nondestructively. We present a method to rapidly carry out such a selection. The method is based on dipping nuts into extraction fluid and examining the resulting fluid by tandem MS without preliminary cleanup. This method has been applied to examine over 65,000 nuts, yielding approximately 120 nuts, each containing more than 250-43000 ng/g aflatoxin (depending on process stream).

  11. Use of Molecular Methods for the Rapid Mass Detection of Schistosoma mansoni (Platyhelminthes: Trematoda) in Biomphalaria spp. (Gastropoda: Planorbidae).

    Science.gov (United States)

    Caldeira, Roberta Lima; Jannotti-Passos, Liana Konovaloffi; Dos Santos Carvalho, Omar

    2017-01-01

    The low stringency-polymerase chain reaction (LS-PCR) and loop-mediated isothermal amplification (LAMP) assays were used to detect the presence of S. mansoni DNA in (1) Brazilian intermediate hosts (Biomphalaria glabrata, B. straminea, and B. tenagophila) with patent S. mansoni infections, (2) B. glabrata snails with prepatent S. mansoni infections, (3) various mixtures of infected and noninfected snails; and (4) snails infected with other trematode species. The assays showed high sensitivity and specificity and could detect S. mansoni DNA when one positive snail was included in a pool of 1,000 negative specimens of Biomphalaria. These molecular approaches can provide a low-cost, effective, and rapid method for detecting the presence of S. mansoni in pooled samples of field-collected Biomphalaria. These assays should aid mapping of transmission sites in endemic areas, especially in low prevalence regions and improve schistosomiasis surveillance. It will be a useful tool to monitor low infection rates of snails in areas where control interventions are leading towards the elimination of schistosomiasis.

  12. Determining the masses and radii of rapidly rotating, oblate neutron stars using energy-resolved waveforms of their X-ray burst oscillations

    Science.gov (United States)

    Lamb, Frederick K.; Miller, M. Coleman

    2014-08-01

    We have developed new, more sophisticated, and much faster Bayesian analysis methods that enable us to estimate the masses and radii of rapidly rotating, oblate neutron stars using the energy-resolved waveforms of their X-ray burst oscillations and to determine the uncertainties in these mass and radius estimates. We first generate the energy-resolved burst oscillation waveforms that would be produced by a hot spot on various rapidly rotating, oblate stars, using the oblate-star Schwarzschild-spacetime (OS) approximation. In generating these synthetic data, we assume that 1 million counts have been collected from the hot spot and that the background is 9 million counts. This produces a realistic modulation amplitude and a total number of counts comparable to the number that could be obtained by a future space mission such as the proposed LOFT or AXTAR missions or the accepted NICER mission by combining data from many bursts from a given star. We then compute the joint posterior distribution of the mass M and radius R in standard models, for each synthetic waveform, and use these posterior distributions to determine the 1-, 2-, and 3-sigma confidence regions in the M-R plane for each synthetic waveform and model. We report here the confidence regions obtained when Schwarzschild+Doppler (S+D) and OS waveform models are used, including results obtained when the properties of the star used to generate the synthetic waveform data differ from the properties of the star used in modeling the waveform. These results are based on research supported by NSF grant AST0709015 at the University of Illinois and NSF grant AST0708424 at the University of Maryland.

  13. Rapid profiling and structural characterization of bioactive compounds and their distribution in different parts of Berberis petiolaris Wall. ex G. Don applying hyphenated mass spectrometric techniques.

    Science.gov (United States)

    Singh, A; Bajpai, V; Srivastava, M; Arya, K R; Kumar, B

    2014-10-15

    Berberis petiolaris Wall. is a lesser known medicinal plant, belonging to the family Berberidaceae. The genus Berberis is known for many biological activities such as anti-microbial, anti-inflammatory and anti-diarrheal, etc. There are not many reports of the isolation of components from Berberis petiolaris. This study aims to seek identification, characterization and quantification of components. A method was developed for rapid screening of phytochemicals using high-pressure liquid chromatography hyphenated with quadrupole time-of-flight mass spectrometry (HPLC/ESI-QTOF-MS/MS). Suitable collision-induced dissociation mass spectrometry (CID-MS/MS) methods were developed for structural investigation of alkaloids, flavanoids and other classes of compounds using nine reference standards for authentication. Multiple reaction monitoring (MRM) methods were developed for quantitative study of five constituents using triple quadrupole-linear ion trap mass spectrometry (UPLC/QqLIT-MS/MS). On the basis of HPLC retention behavior and fragmentation pathways obtained by high-resolution MS and MS/MS, 32 compounds were identified and characterized in different parts of Berberis petiolaris. Quantitative studies of chlorogenic acid, magnoflorine, jatrorrhizine, palmatine and berberine were also completed successfully. Rapid and accurate HPLC/ESI-QTOF-MS/MS and UPLC/ESI-QqLIT-MS/MS methods were established for identification, characterization and quantification of phytochemicals in the ethanolic extract of Berberis petiolaris. These methods, therefore, can be used for studies on phytochemical variation in different parts of the plant. Principle components analysis (PCA) may be used for plant part discrimination. Copyright © 2014 John Wiley & Sons, Ltd.

  14. Magnetic solid phase extraction coupled with desorption corona beam ionization-mass spectrometry for rapid analysis of antidepressants in human body fluids.

    Science.gov (United States)

    Chen, Di; Zheng, Hao-Bo; Huang, Yun-Qing; Hu, Yu-Ning; Yu, Qiong-Wei; Yuan, Bi-Feng; Feng, Yu-Qi

    2015-08-21

    Ambient ionization techniques show good potential in rapid analysis of target compounds. However, a direct application of these ambient ionization techniques for the determination of analytes in a complex matrix is difficult due to the matrix interference and ion suppression. To resolve this problem, here we developed a strategy by coupling magnetic solid phase extraction (MSPE) with desorption corona beam ionization (DCBI)-mass spectrometry (MS). As a proof of concept, the pyrrole-coated Fe3O4 magnetic nanoparticles (Fe3O4@Ppy) were prepared and used for the extraction of antidepressants. After extraction, the Fe3O4@Ppy with trapped antidepressants was then directly subjected to DCBI-MS analysis with the aid of a homemade magnetic glass capillary. As the MSPE process is rapid and the direct DCBI-MS analysis does not need solvent desorption or chromatographic separation processes, the overall analysis can be completed within 3 min. The proposed MSPE-DCBI-MS method was then successfully used to determine antidepressants in human urine and plasma. The calibration curves were obtained in the range of 0.005-0.5 μg mL(-1) for urine and 0.02-1 μg mL(-1) for plasma with reasonable linearity (R(2) > 0.951). The limits of detection of three antidepressants were in the range of 0.2-1 ng mL(-1) for urine and 2-5 ng mL(-1) for plasma. Acceptable reproducibility for rapid analysis was achieved with relative standard deviations less than 19.1% and the relative recoveries were 85.2-118.7%. Taken together, the developed MSPE-DCBI-MS strategy offers a powerful capacity for rapid analysis of target compounds in a complex matrix, which would greatly expand the applications of ambient ionization techniques with plentiful magnetic sorbents.

  15. Rapid analysis of Fructus forsythiae essential oil by ionic liquids-assisted microwave distillation coupled with headspace single-drop microextraction followed by gas chromatography-mass spectrometry.

    Science.gov (United States)

    Jiao, Jiao; Ma, Dan-Hui; Gai, Qing-Yan; Wang, Wei; Luo, Meng; Fu, Yu-Jie; Ma, Wei

    2013-12-04

    A rapid, green and effective miniaturized sample preparation and analytical technique, i.e. ionic liquids-assisted microwave distillation coupled with headspace single-drop microextraction (ILAMD-HS-SDME) followed by gas chromatography-mass spectrometry (GC-MS) was developed for the analysis of essential oil (EO) in Fructus forsythiae. In this work, ionic liquids (ILs) were not only used as the absorption medium of microwave irradiation but also as the destruction agent of plant cell walls. 1-Ethyl-3-methylimidazolium acetate ([C2mim]OAc) was chosen as the optimal ILs. Moreover, n-heptadecane (2.0 μL) was selected as the appropriate suspended solvent for the extraction and concentration of EO. Extraction conditions of the proposed method were optimized using the relative peak area of EO constituents as the index, and the optimal operational parameters were obtained as follows: irradiation power (300 W), sample mass (0.7 g), mass ratio of ILs to sample (2.4), temperature (78°C) and time (3.4 min). In comparison to previous reports, the proposed method was faster and required smaller sample amount but could equally monitor all EO constituents with no significant differences. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. Use of a cholera rapid diagnostic test during a mass vaccination campaign in response to an epidemic in Guinea, 2012.

    Directory of Open Access Journals (Sweden)

    Isabel Martinez-Pino

    Full Text Available BACKGROUND: During the 2012 cholera outbreak in the Republic of Guinea, the Ministry of Health, supported by Médecins Sans Frontières - Operational Center Geneva, used the oral cholera vaccine Shanchol as a part of the emergency response. The rapid diagnostic test (RDT Crystal VC, widely used during outbreaks, detects lipopolysaccharide antigens of Vibrio cholerae O1 and O139, both included in Shanchol. In the context of reactive use of a whole-cell cholera vaccine in a region where cholera cases have been reported, it is essential to know what proportion of vaccinated individuals would be reactive to the RDT and for how long after vaccination. METHODOLOGY/PRINCIPAL FINDINGS: A total of 108 vaccinated individuals, selected systematically among all persons older than one year, were included at vaccination sites and 106 were included in the analysis. Stools samples of this cohort of vaccinated participants were collected and tested with the RDT every day until the test was negative for two consecutive visits or for a maximum of 7 days. A total of 94.3% of cholera vaccine recipients had a positive test after vaccination; all except one of these positive results were reactive only with the O139 antigen. The mean time to become negative in those with an initial positive result after vaccination was 3.8 days, standard deviation 1.1 days. CONCLUSIONS/SIGNIFICANCE: The RDT Crystal VC becomes positive in persons recently vaccinated against cholera, although almost exclusively to the O139 antigen. This reactivity largely disappeared within five days after vaccination. These results suggest that the test can be used normally as soon as 24 hours after vaccination in a context of O1 epidemics, which represent the vast majority of cases, and after a period of five days in areas where V. cholerae O139 is present. The reason why only O139 test line became positive remains to be investigated.

  17. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry for rapid identification of fungal rhinosinusitis pathogens.

    Science.gov (United States)

    Huang, Yanfei; Wang, Jinglin; Zhang, Mingxin; Zhu, Min; Wang, Mei; Sun, Yufeng; Gu, Haitong; Cao, Jingjing; Li, Xue; Zhang, Shaoya; Lu, Xinxin

    2017-03-01

    Filamentous fungi are among the most important pathogens, causing fungal rhinosinusitis (FRS). Current laboratory diagnosis of FRS pathogens mainly relies on phenotypic identification by culture and microscopic examination, which is time consuming and expertise dependent. Although matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) MS has been employed to identify various fungi, its efficacy in the identification of FRS fungi is less clear. A total of 153 FRS isolates obtained from patients were analysed at the Clinical Laboratory at the Beijing Tongren Hospital affiliated to the Capital Medical University, between January 2014 and December 2015. They were identified by traditional phenotypic methods and Bruker MALDI-TOF MS (Bruker, Biotyper version 3.1), respectively. Discrepancies between the two methods were further validated by sequencing. Among the 153 isolates, 151 had correct species identification using MALDI-TOF MS (Bruker, Biot 3.1, score ≥2.0 or 2.3). MALDI-TOF MS enabled identification of some very closely related species that were indistinguishable by conventional phenotypic methods, including 1/10 Aspergillus versicolor, 3/20 Aspergillus flavus, 2/30 Aspergillus fumigatus and 1/20 Aspergillus terreus, which were misidentified by conventional phenotypic methods as Aspergillus nidulans, Aspergillus oryzae, Aspergillus japonicus and Aspergillus nidulans, respectively. In addition, 2/2 Rhizopus oryzae and 1/1 Rhizopus stolonifer that were identified only to the genus level by the phenotypic method were correctly identified by MALDI-TOF MS. MALDI-TOF MS is a rapid and accurate technique, and could replace the conventional phenotypic method for routine identification of FRS fungi in clinical microbiology laboratories.

  18. MOOC Design – Dissemination to the Masses or Facilitation of Social Learning and a Deep Approach to Learning?

    DEFF Research Database (Denmark)

    Christensen, Inger-Marie F.; Dam Laursen, Mette; Bøggild, Jacob

    2016-01-01

    This article accounts for the design of the massive open online course (MOOC) Hans Christian Andersen’s Fairy tales on FutureLearn and reports on the effectiveness of this design in terms of engaging learners in social learning and encouraging a deep approach to learning. A learning pathway...... was designed that provided learners with relevant knowledge, allowed them to practice their analysis skills and provided model responses. In the first run of the MOOC, a light facilitation approach was used to motivate and engage learners. In the second run, this was supplemented with live Q & A sessions...... and increased educator feedback. Course data show that that some learners use the space provided for social interaction and mutual support. A learning pathway that engages learners in discussion and progression from week to week facilitates a deep approach to learning. However, this requires more support from...

  19. Rapid Quantification of Major Volatile Metabolites in Fermented Food and Beverages Using Gas Chromatography-Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Farhana R. Pinu

    2017-07-01

    Full Text Available Here we present a method for the accurate quantification of major volatile metabolites found in different food and beverages, including ethanol, acetic acid and other aroma compounds, using gas chromatography coupled to mass spectrometry (GC-MS. The method is combined with a simple sample preparation procedure using sodium chloride and anhydrous ethyl acetate. The GC-MS analysis was accomplished within 4.75 min, and over 80 features were detected, of which 40 were positively identified using an in-house and a commercialmass spectrometry (MS library. We determined different analytical parameters of these metabolites including the limit of detection (LOD, limit of quantitation (LOQ and range of quantification. In order to validate the method, we also determined detailed analytical characteristics of five major fermentation end products including ethanol, acetic acid, isoamyl alcohol, ethyl-L-lactate and, acetoin. The method showed very low technical variability for the measurements of these metabolites in different matrices (<3% with an excellent accuracy (100% ± 5%, recovery (100% ± 10%, reproducibility and repeatability [Coefficient of variation (CV 1–10%]. To demonstrate the applicability of the method, we analysed different fermented products including balsamic vinegars, sourdough, distilled (whisky and non-distilled beverages (wine and beer.

  20. Rapid and sensitive detection of carbapenemase activity in Acinetobacter baumannii using superficially porous liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Lin, Huei-Ru; Hu, Anren; Lai, Meng-Jiun; Chiang, Chih-Wei; Liao, Chao-Chuan; Chang, Kai-Chih

    2016-12-01

    The emergence and spread of carbapenem-resistant Acinetobacter baumannii poses a challenge for optimizing antibiotic therapies and preventing outbreaks. Traditional phenotypic assays such as the modified Hodge test (MHT) or polymerase chain reaction (PCR)-based detection of the carbapenemase genes are time-consuming and complicated. Therefore, new approaches for the efficient detection of carbapenemase-producing A. baumannii are urgently required. In this study, we used the superficially porous liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay to measure carbapenem hydrolysis in a solution spiked with test strains of A. baumannii. The rate of carbapenem hydrolysis during incubation was expressed as the ratio of the carbapenem peak area of the test A. baumannii strains to the noncarbapenemase-producing A. baumannii ATCC 17978. This method can accurately measure the carbapenem hydrolysis rate and, therefore, can effectively identify carbapenemase-producing strains within 75 minutes. A total of 112 A. baumannii strains were used in this study, including 103 clinical isolates with 68 carbapenem-resistant strains and 35 carbapenem-susceptible strains, seven ATCC strains and two selected mutants. The results of the superficially porous LC-MS/MS assay showed higher detection sensitivity compared to the results of the MHT. Our results demonstrate the ability of the former method to routinely detect carbapenemase-producing A. baumannii. Copyright © 2015. Published by Elsevier B.V.

  1. Liquid Chromatography-Mass Spectrometry-Based Rapid Secondary-Metabolite Profiling of Marine Pseudoalteromonas sp. M2

    Directory of Open Access Journals (Sweden)

    Woo Jung Kim

    2016-01-01

    Full Text Available The ocean is a rich resource of flora, fauna, and food. A wild-type bacterial strain showing confluent growth on marine agar with antibacterial activity was isolated from marine water, identified using 16S rDNA sequence analysis as Pseudoalteromonas sp., and designated as strain M2. This strain was found to produce various secondary metabolites including quinolone alkaloids. Using high-resolution mass spectrometry (MS and nuclear magnetic resonance (NMR analysis, we identified nine secondary metabolites of 4-hydroxy-2-alkylquinoline (pseudane-III, IV, V, VI, VII, VIII, IX, X, and XI. Additionally, this strain produced two novel, closely related compounds, 2-isopentylqunoline-4-one and 2-(2,3-dimetylbutylqunoline-4-(1H-one, which have not been previously reported from marine bacteria. From the metabolites produced by Pseudoalteromonas sp. M2, 2-(2,3-dimethylbutylquinolin-4-one, pseudane-VI, and pseudane-VII inhibited melanin synthesis in Melan-A cells by 23.0%, 28.2%, and 42.7%, respectively, wherein pseudane-VII showed the highest inhibition at 8 µg/mL. The results of this study suggest that liquid chromatography (LC-MS/MS-based metabolite screening effectively improves the efficiency of novel metabolite discovery. Additionally, these compounds are promising candidates for further bioactivity development.

  2. Development of a loop-mediated isothermal amplification method for rapid mass-screening of sand flies for Leishmania infection.

    Science.gov (United States)

    Nzelu, Chukwunonso O; Gomez, Eduardo A; Cáceres, Abraham G; Sakurai, Tatsuya; Martini-Robles, Luiggi; Uezato, Hiroshi; Mimori, Tatsuyuki; Katakura, Ken; Hashiguchi, Yoshihisa; Kato, Hirotomo

    2014-04-01

    Entomological monitoring of Leishmania infection in leishmaniasis endemic areas offers epidemiologic advantages for predicting the risk and expansion of the disease, as well as evaluation of the effectiveness of control programs. In this study, we developed a highly sensitive loop-mediated isothermal amplification (LAMP) method for the mass screening of sand flies for Leishmania infection based on the 18S rRNA gene. The LAMP technique could detect 0.01 parasites, which was more sensitive than classical PCR. The method was robust and could amplify the target DNA within 1h from a crude sand fly template without DNA purification. Amplicon detection could be accomplished by the newly developed colorimetric malachite green (MG)--mediated naked eye visualization. Pre-addition of MG to the LAMP reaction solution did not inhibit amplification efficiency. The field applicability of the colorimetric MG-based LAMP assay was demonstrated with 397 field-caught samples from the endemic areas of Ecuador and eight positive sand flies were detected. The robustness, superior sensitivity, and ability to produce better visual discriminatory reaction products than existing LAMP fluorescence and turbidity assays indicated the field potential usefulness of this new method for surveillance and epidemiological studies of leishmaniasis in developing countries. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. [Rapid determination of 6 pesticide residues in tomato paste by ultra performance liquid chromatography-tandem mass spectrometry].

    Science.gov (United States)

    Su, Min; Li, Shiyu; Li, Fengge; Gong, Zhiguo; Wang, Jinhua

    2011-11-01

    An ultra performance liquid chromatography-tandem mass spectrometric method (UPLC-MS/MS) was established for the simultaneous determination of imidacloprid, carbendazim, thiophanate-methyl, propamocarb, methomyl and dimethomorph residues in tomato paste. The samples were extracted by methanol-water (1: 1, v/v) containing 0.1% (v/v) acetic acid. The separation was performed on a Waters Acquity UPLC system with a BEH C18 column with the gradient elution of methanol and water (containing 10 mmol/L ammonium acetate). The six pesticides were determined in the modes of electrospray positive ionization (ESI+) and multiple reaction monitoring (MRM). The analytes were quantified by matrix-matched standard solution, and the calibration curves showed good linearity within the concentrations of 0.005 to 0.2 mg/L and the correlation coefficients (r) were more than 0.995. The average recoveries of the six pesticides ranged from 66.8% to 102.9% in the three spiked levels of 0.02, 0.05 and 0.2 mg/kg. The relative standard deviations (RSDs) were all less than 15%. The limits of quantification (LOQ, S/N > 10) were 0.02 mg/kg for the all analytes. The results indicate that the method is easier, faster, more sensitive, and suitable for the qualitative and quantitative confirmation of the six pesticide residues from tomato paste.

  4. A rapid liquid chromatography tandem mass spectrometry-based method for measuring propranolol on dried blood spots.

    Science.gov (United States)

    Della Bona, Maria Luisa; Malvagia, Sabrina; Villanelli, Fabio; Giocaliere, Elisa; Ombrone, Daniela; Funghini, Silvia; Filippi, Luca; Cavallaro, Giacomo; Bagnoli, Paola; Guerrini, Renzo; la Marca, Giancarlo

    2013-05-05

    Propranolol, a non-selective beta blocker drug, is used in young infants and newborns for treating several heart diseases; its pharmacokinetics has been extensively evaluated in adult patients using extrapolation to treat pediatric population. The purpose of the present study was to develop and validate a method to measure propranolol levels in dried blood spots. The analysis was performed by using liquid chromatography/tandem mass spectrometry operating in multiple reaction monitoring mode. The calibration curve in matrix was linear in the concentration range of 2.5-200 μg/L with correlation coefficient r=0.9996. Intra-day and inter-day precisions and biases were less than 8.0% (n=10) and 11.5% (n=10) respectively. The recoveries ranged from 94 to 100% and the matrix effect did not result in a severe signal suppression. Propranolol on dried blood spot showed a good stability at three different temperatures for one month. This paper describes a micromethod for measuring propranolol levels on dried blood spot, which determines a great advantage in neonates or young infants during pharmacokinetic studies because of less invasive sampling and small blood volume required. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. Rapid Quantification of Major Volatile Metabolites in Fermented Food and Beverages Using Gas Chromatography-Mass Spectrometry.

    Science.gov (United States)

    Pinu, Farhana R; Villas-Boas, Silas G

    2017-07-26

    Here we present a method for the accurate quantification of major volatile metabolites found in different food and beverages, including ethanol, acetic acid and other aroma compounds, using gas chromatography coupled to mass spectrometry (GC-MS). The method is combined with a simple sample preparation procedure using sodium chloride and anhydrous ethyl acetate. The GC-MS analysis was accomplished within 4.75 min, and over 80 features were detected, of which 40 were positively identified using an in-house and a commercialmass spectrometry (MS) library. We determined different analytical parameters of these metabolites including the limit of detection (LOD), limit of quantitation (LOQ) and range of quantification. In order to validate the method, we also determined detailed analytical characteristics of five major fermentation end products including ethanol, acetic acid, isoamyl alcohol, ethyl-L-lactate and, acetoin. The method showed very low technical variability for the measurements of these metabolites in different matrices (<3%) with an excellent accuracy (100% ± 5%), recovery (100% ± 10%), reproducibility and repeatability [Coefficient of variation (CV) 1-10%)]. To demonstrate the applicability of the method, we analysed different fermented products including balsamic vinegars, sourdough, distilled (whisky) and non-distilled beverages (wine and beer).

  6. A rapid method for simultaneous determination of arsenic, cadmium and lead in drinking water by inductively coupled plasma mass spectrometry

    Directory of Open Access Journals (Sweden)

    Joshua Rey P. Torres

    Full Text Available The raw water source of drinking water in most areas in the Philippines is typically river water and in some cases groundwater. These sources are prone to elevated levels of metals and metalloids that may cause exposure of the general population when the treatment of the water is inadequate. This work presents a simple method based on EPA Method 200.8 for the determination of total concentrations of arsenic (As, cadmium (Cd and lead (Pb in drinking water using inductively coupled plasma-mass spectrometry (ICP-MS as the element-selective detector. This was applied in the determination of these elements in the water supply in Metro Manila, Philippines. The method detection limits were 0.095 μg L-1, 0.043 μg L-1, and 0.114 μg L-1 for total As, Cd and Pb, respectively.The method was validated using National Institute of Standards and Technology (NIST 1643e certified reference material for trace elements in water and determined values were 60.4 ± 0.5 μg L-1, 6.7 ± 0.1 μg L-1, and 19.6 ± 0.5 μg L-1 for As, Cd and Pb, respectively. These determined values were in good agreement with the certified values in the reference material. Analysis of actual drinking water samples showed that most samples did not exceed the limit of the Philippine drinking water standard for the elements.

  7. [Rapid determination of benzene series in seawater by gas chromatography-mass spectrometry with static headspace extraction].

    Science.gov (United States)

    Bai, Hongyan; Han, Bin; Chen, Junhui; Zheng, Li; Yang, Dongfang; Wang, Xiaoru

    2012-05-01

    A method for the simultaneous determination of 13 benzene series (BTEX) in seawater using gas chromatography-mass spectrometry with static headspace extraction (HS-GC/MS) was developed. To carefully characterize the performance of this method, several factors affecting parameters were studied in detail, such as the type of column, heating procedure, equilibrium temperature, equilibrium time and the volume ratio of gas phase to liquid phase. The optimized conditions were as follows: the polar column of DB-WAX; heating procedure, 40 degrees C kept for 4 min, then raised to 120 degrees C at 10 degrees C/min, to 180 degrees C at 25 degrees C/min; equilibrium temperature, 80 degrees C; equilibrium time, 10 min; and the volume ratio of gas phase to liquid phase, 1:1. Under the optimized conditions, the linear equations were obtained in the concentration range of 0.16-320 microg/L with correlation coefficients greater than 0.999. The limits of detection (S/N = 3) were 0.019-0.033 microg/L. The recoveries at the three spiked levels of 1.6, 16 and 160 microg/L ranged from 81. 25% to 103.73% with the relative standard deviations (RSD, n=6) from 0.3% to 4.4%. The analytical results of the practical seawater samples from Shanghai Huangpu District were satisfactory. The determination of the 13 benzene series can be finished in 12 min. The method is simple, accurate, reliable, efficient and environmental-friendly.

  8. Rapid identification of Burkholderia mallei and Burkholderia pseudomallei by intact cell Matrix-assisted Laser Desorption/Ionisation mass spectrometric typing

    Science.gov (United States)

    2012-01-01

    Background Burkholderia (B.) pseudomallei and B. mallei are genetically closely related species. B. pseudomallei causes melioidosis in humans and animals, whereas B. mallei is the causative agent of glanders in equines and rarely also in humans. Both agents have been classified by the CDC as priority category B biological agents. Rapid identification is crucial, because both agents are intrinsically resistant to many antibiotics. Matrix-assisted laser desorption/ionisation mass spectrometry (MALDI-TOF MS) has the potential of rapid and reliable identification of pathogens, but is limited by the availability of a database containing validated reference spectra. The aim of this study was to evaluate the use of MALDI-TOF MS for the rapid and reliable identification and differentiation of B. pseudomallei and B. mallei and to build up a reliable reference database for both organisms. Results A collection of ten B. pseudomallei and seventeen B. mallei strains was used to generate a library of reference spectra. Samples of both species could be identified by MALDI-TOF MS, if a dedicated subset of the reference spectra library was used. In comparison with samples representing B. mallei, higher genetic diversity among B. pseudomallei was reflected in the higher average Eucledian distances between the mass spectra and a broader range of identification score values obtained with commercial software for the identification of microorganisms. The type strain of B. pseudomallei (ATCC 23343) was isolated decades ago and is outstanding in the spectrum-based dendrograms probably due to massive methylations as indicated by two intensive series of mass increments of 14 Da specifically and reproducibly found in the spectra of this strain. Conclusions Handling of pathogens under BSL 3 conditions is dangerous and cumbersome but can be minimized by inactivation of bacteria with ethanol, subsequent protein extraction under BSL 1 conditions and MALDI-TOF MS analysis being faster than

  9. Rapid identification of Burkholderia mallei and Burkholderia pseudomallei by intact cell Matrix-assisted Laser Desorption/Ionisation mass spectrometric typing.

    Science.gov (United States)

    Karger, Axel; Stock, Rüdiger; Ziller, Mario; Elschner, Mandy C; Bettin, Barbara; Melzer, Falk; Maier, Thomas; Kostrzewa, Markus; Scholz, Holger C; Neubauer, Heinrich; Tomaso, Herbert

    2012-10-10

    Burkholderia (B.) pseudomallei and B. mallei are genetically closely related species. B. pseudomallei causes melioidosis in humans and animals, whereas B. mallei is the causative agent of glanders in equines and rarely also in humans. Both agents have been classified by the CDC as priority category B biological agents. Rapid identification is crucial, because both agents are intrinsically resistant to many antibiotics. Matrix-assisted laser desorption/ionisation mass spectrometry (MALDI-TOF MS) has the potential of rapid and reliable identification of pathogens, but is limited by the availability of a database containing validated reference spectra. The aim of this study was to evaluate the use of MALDI-TOF MS for the rapid and reliable identification and differentiation of B. pseudomallei and B. mallei and to build up a reliable reference database for both organisms. A collection of ten B. pseudomallei and seventeen B. mallei strains was used to generate a library of reference spectra. Samples of both species could be identified by MALDI-TOF MS, if a dedicated subset of the reference spectra library was used. In comparison with samples representing B. mallei, higher genetic diversity among B. pseudomallei was reflected in the higher average Eucledian distances between the mass spectra and a broader range of identification score values obtained with commercial software for the identification of microorganisms. The type strain of B. pseudomallei (ATCC 23343) was isolated decades ago and is outstanding in the spectrum-based dendrograms probably due to massive methylations as indicated by two intensive series of mass increments of 14 Da specifically and reproducibly found in the spectra of this strain. Handling of pathogens under BSL 3 conditions is dangerous and cumbersome but can be minimized by inactivation of bacteria with ethanol, subsequent protein extraction under BSL 1 conditions and MALDI-TOF MS analysis being faster than nucleic amplification methods. Our

  10. Rapid identification of Burkholderia mallei and Burkholderia pseudomallei by intact cell Matrix-assisted Laser Desorption/Ionisation mass spectrometric typing

    Directory of Open Access Journals (Sweden)

    Karger Axel

    2012-10-01

    Full Text Available Abstract Background Burkholderia (B. pseudomallei and B. mallei are genetically closely related species. B. pseudomallei causes melioidosis in humans and animals, whereas B. mallei is the causative agent of glanders in equines and rarely also in humans. Both agents have been classified by the CDC as priority category B biological agents. Rapid identification is crucial, because both agents are intrinsically resistant to many antibiotics. Matrix-assisted laser desorption/ionisation mass spectrometry (MALDI-TOF MS has the potential of rapid and reliable identification of pathogens, but is limited by the availability of a database containing validated reference spectra. The aim of this study was to evaluate the use of MALDI-TOF MS for the rapid and reliable identification and differentiation of B. pseudomallei and B. mallei and to build up a reliable reference database for both organisms. Results A collection of ten B. pseudomallei and seventeen B. mallei strains was used to generate a library of reference spectra. Samples of both species could be identified by MALDI-TOF MS, if a dedicated subset of the reference spectra library was used. In comparison with samples representing B. mallei, higher genetic diversity among B. pseudomallei was reflected in the higher average Eucledian distances between the mass spectra and a broader range of identification score values obtained with commercial software for the identification of microorganisms. The type strain of B. pseudomallei (ATCC 23343 was isolated decades ago and is outstanding in the spectrum-based dendrograms probably due to massive methylations as indicated by two intensive series of mass increments of 14 Da specifically and reproducibly found in the spectra of this strain. Conclusions Handling of pathogens under BSL 3 conditions is dangerous and cumbersome but can be minimized by inactivation of bacteria with ethanol, subsequent protein extraction under BSL 1 conditions and MALDI-TOF MS

  11. Rapid evaporative ionisation mass spectrometry of electrosurgical vapours for the identification of breast pathology: towards an intelligent knife for breast cancer surgery.

    Science.gov (United States)

    St John, Edward R; Balog, Julia; McKenzie, James S; Rossi, Merja; Covington, April; Muirhead, Laura; Bodai, Zsolt; Rosini, Francesca; Speller, Abigail V M; Shousha, Sami; Ramakrishnan, Rathi; Darzi, Ara; Takats, Zoltan; Leff, Daniel R

    2017-05-23

    Re-operation for positive resection margins following breast-conserving surgery occurs frequently (average = 20-25%), is cost-inefficient, and leads to physical and psychological morbidity. Current margin assessment techniques are slow and labour intensive. Rapid evaporative ionisation mass spectrometry (REIMS) rapidly identifies dissected tissues by determination of tissue structural lipid profiles through on-line chemical analysis of electrosurgical aerosol toward real-time margin assessment. Electrosurgical aerosol produced from ex-vivo and in-vivo breast samples was aspirated into a mass spectrometer (MS) using a monopolar hand-piece. Tissue identification results obtained by multivariate statistical analysis of MS data were validated by histopathology. Ex-vivo classification models were constructed from a mass spectral database of normal and tumour breast samples. Univariate and tandem MS analysis of significant peaks was conducted to identify biochemical differences between normal and cancerous tissues. An ex-vivo classification model was used in combination with bespoke recognition software, as an intelligent knife (iKnife), to predict the diagnosis for an ex-vivo validation set. Intraoperative REIMS data were acquired during breast surgery and time-synchronized to operative videos. A classification model using histologically validated spectral data acquired from 932 sampling points in normal tissue and 226 in tumour tissue provided 93.4% sensitivity and 94.9% specificity. Tandem MS identified 63 phospholipids and 6 triglyceride species responsible for 24 spectral differences between tissue types. iKnife recognition accuracy with 260 newly acquired fresh and frozen breast tissue specimens (normal n = 161, tumour n = 99) provided sensitivity of 90.9% and specificity of 98.8%. The ex-vivo and intra-operative method produced visually comparable high intensity spectra. iKnife interpretation of intra-operative electrosurgical vapours, including data

  12. Class and Home Problems. Identify-Solve-Broadcast Your Own Transport Phenomenon: Student-Created YouTube Videos to Foster Active Learning in Mass and Heat Transfer

    Science.gov (United States)

    Wen, Fei; Khera, Eshita

    2016-01-01

    Despite the instinctive perception of mass and heat transfer principles in daily life, productive learning in this course continues to be one of the greatest challenges for undergraduate students in chemical engineering. In an effort to enhance student learning in classroom, we initiated an innovative active-learning method titled…

  13. The learning curve is rapid in medical termination of pregnancy--first-year results from the Helsinki area.

    Science.gov (United States)

    Suhonen, Satu; Heikinheimo, Oskari; Tikka, Marja; Haukkamaa, Maija

    2003-03-01

    Medical termination of pregnancy by means of mifepristone and prostaglandin became available in Finland in May 2000. We summarize the first year results of medical abortion in a large tertiary care unit in Helsinki. A regimen of 200 mg of mifepristone followed by 0.4 mg vaginally administered misoprostol 2 days later was used. The maximum duration of pregnancy was 56 days. Four hundred and seventeen women, 47% of those with a pregnancy duration of up to 56 days, chose medical instead of surgical abortion. The monthly percentage of medical abortions varied from 27% to 63%. The percentage of complete terminations increased from 92% among the first quarter of the subjects to 97% among the fourth quarter, the overall success rate being 95%. Subject satisfaction, duration and self-estimated amount of bleeding, as well as analgesia needs were similar to those reported elsewhere. Most subjects (61%) chose combined oral contraceptive (COC) pills for future contraception; 75% of the COCs were started around the day of misoprostol administration. The reported amounts and duration of bleeding were not influenced by the immediate start of oral contraceptives. Intrauterine contraception was planned for 28% of the subjects, and 16% of them chose a levonorgestrel-releasing intrauterine device. We conclude that the learning curve in medical termination of pregnancy is rapid, and results comparable to those in centers with extensive experience with the method can be reached within the first year.

  14. Rapid Screening Technique To Identify Sudan Dyes (I to IV) in Adulterated Tomato Sauce, Chilli Powder, and Palm Oil by Innovative High-Resolution Mass Spectrometry.

    Science.gov (United States)

    Sciuto, Simona; Esposito, Giovanna; Dell'Atti, Luana; Guglielmetti, Chiara; Acutis, Pier Luigi; Martucci, Francesca

    2017-04-01

    Sudan dyes are synthetic azo dyes used by industry in a variety of applications. Classified as carcinogenic, they are not allowed in foodstuffs; however, their presence as adulterants in food products has been regularly reported. Here, we describe an innovative screening method to detect Sudan I, II, III, and IV in tomato sauce, palm oil, and chilli powder. The method entails minimal sample preparation, completely avoiding the liquid chromatography phase, followed by detection and identification through atmospheric pressure chemical ionization time-of-flight mass spectrometry, in positive ionization mode. Analytes were efficiently identified and detected in samples, fortified both with individual analytes and with their mixture, with an error in mass identification less than 5 ppm. Limits of identification of the analytes in the fortified samples were 0.5 to 1 mg/kg, depending on the dye and matrix. The method had a linear range of 0.05 to 5 mg/kg and good linear relationships (R2 > 0.98). Repeatability was satisfactory, with a coefficient of variation lower than 20%. The method was applied to detect the dyes in real adulterated chilli samples, previously found positive by confirmatory high-performance liquid chromatography-mass spectrometry and ELISA, and in commercial products purchased from supermarkets. In all positive samples, analytes were correctly identified with an error in mass identification lower than 5 ppm, while none of the 45 commercial samples analyzed were found to be contaminated. The proposed new assay is sensitive, with a limit of identification, for all the three matrices, complying with the limits defined by the European Union (0.5 to 1 mg/kg) for analytical methods. Compared with conventional methods, the new assay is rapid and inexpensive and characterized by a high throughput; thus, it could be suitable as screening technique to identify Sudan dyes in adulterated food products.

  15. Rapid Profiling of Bovine and Human Milk Gangliosides by Matrix-Assisted Laser Desorption/Ionization Fourier Transform Ion Cyclotron Resonance Mass Spectrometry.

    Science.gov (United States)

    Lee, Hyeyoung; An, Hyun Joo; Lerno, Larry A; German, J Bruce; Lebrilla, Carlito B

    2011-08-15

    Gangliosides are anionic glycosphingolipids widely distributed in vertebrate tissues and fluids. Their structural and quantitative expression patterns depend on phylogeny and are distinct down to the species level. In milk, gangliosides are exclusively associated with the milk fat globule membrane. They may participate in diverse biological processes but more specifically to host-pathogen interactions. However, due to the molecular complexities, the analysis needs extensive sample preparation, chromatographic separation, and even chemical reaction, which makes the process very complex and time-consuming. Here, we describe a rapid profiling method for bovine and human milk gangliosides employing matrix-assisted desorption/ionization (MALDI) Fourier transform ion cyclotron resonance (FTICR) mass spectrometry (MS). Prior to the analyses of biological samples, milk ganglioside standards GM3 and GD3 fractions were first analyzed in order to validate this method. High mass accuracy and high resolution obtained from MALDI FTICR MS allow for the confident assignment of chain length and degree of unsaturation of the ceramide. For the structural elucidation, tandem mass spectrometry (MS/MS), specifically as collision-induced dissociation (CID) and infrared multiphoton dissociation (IRMPD) were employed. Complex ganglioside mixtures from bovine and human milk were further analyzed with this method. The samples were prepared by two consecutive chloroform/methanol extraction and solid phase extraction. We observed a number of differences between bovine milk and human milk. The common gangliosides in bovine and human milk are NeuAc-NeuAc-Hex-Hex-Cer (GD3) and NeuAc-Hex-Hex-Cer (GM3); whereas, the ion intensities of ganglioside species are different between two milk samples. Kendrick mass defect plot yields grouping of ganglioside peaks according to their structural similarities. Gangliosides were further probed by tandem MS to confirm the compositional and structural assignments

  16. Rapid "breath-print" of liver cirrhosis by proton transfer reaction time-of-flight mass spectrometry. A pilot study.

    Directory of Open Access Journals (Sweden)

    Filomena Morisco

    Full Text Available UNLABELLED: The aim of the present work was to test the potential of Proton Transfer Reaction Time-of-Flight Mass Spectrometry (PTR-ToF-MS in the diagnosis of liver cirrhosis and the assessment of disease severity by direct analysis of exhaled breath. Twenty-six volunteers have been enrolled in this study: 12 patients (M/F 8/4, mean age 70.5 years, min-max 42-80 years with liver cirrhosis of different etiologies and at different severity of disease and 14 healthy subjects (M/F 5/9, mean age 52.3 years, min-max 35-77 years. Real time breath analysis was performed on fasting subjects using a buffered end-tidal on-line sampler directly coupled to a PTR-ToF-MS. Twelve volatile organic compounds (VOCs resulted significantly differently in cirrhotic patients (CP compared to healthy controls (CTRL: four ketones (2-butanone, 2- or 3- pentanone, C8-ketone, C9-ketone, two terpenes (monoterpene, monoterpene related, four sulphur or nitrogen compounds (sulfoxide-compound, S-compound, NS-compound, N-compound and two alcohols (heptadienol, methanol. Seven VOCs (2-butanone, C8-ketone, a monoterpene, 2,4-heptadienol and three compounds containing N, S or NS resulted significantly differently in compensate cirrhotic patients (Child-Pugh A; CP-A and decompensated cirrhotic subjects (Child-Pugh B+C; CP-B+C. ROC (Receiver Operating Characteristic analysis was performed considering three contrast groups: CP vs CTRL, CP-A vs CTRL and CP-A vs CP-B+C. In these comparisons monoterpene and N-compound showed the best diagnostic performance. CONCLUSIONS: Breath analysis by PTR-ToF-MS was able to distinguish cirrhotic patients from healthy subjects and to discriminate those with well compensated liver disease from those at more advanced severity stage. A breath-print of liver cirrhosis was assessed for the first time.

  17. SU-E-T-23: A Developing Australian Network for Datamining and Modelling Routine Radiotherapy Clinical Data and Radiomics Information for Rapid Learning and Clinical Decision Support

    Energy Technology Data Exchange (ETDEWEB)

    Thwaites, D [University of Sydney, Camperdown, Sydney (Australia); Holloway, L [Ingham Institute, Sydney, NSW (Australia); Bailey, M; Carolan, M; Miller, A [Illawarra Cancer Care Centre, Wollongong, NSW (Australia); Barakat, S; Field, M [University of Sydney, Sydney, NSW (Australia); Delaney, G; Vinod, S [Liverpool Hospital, Liverpool, NSW (Australia); Dekker, A [Maastro Clinic, Maastricht (Netherlands); Lustberg, T; Soest, J van; Walsh, S [MAASTRO Clinic, Maastricht (Netherlands)

    2015-06-15

    Purpose: Large amounts of routine radiotherapy (RT) data are available, which can potentially add clinical evidence to support better decisions. A developing collaborative Australian network, with a leading European partner, aims to validate, implement and extend European predictive models (PMs) for Australian practice and assess their impact on future patient decisions. Wider objectives include: developing multi-institutional rapid learning, using distributed learning approaches; and assessing and incorporating radiomics information into PMs. Methods: Two initial standalone pilots were conducted; one on NSCLC, the other on larynx, patient datasets in two different centres. Open-source rapid learning systems were installed, for data extraction and mining to collect relevant clinical parameters from the centres’ databases. The European DSSs were learned (“training cohort”) and validated against local data sets (“clinical cohort”). Further NSCLC studies are underway in three more centres to pilot a wider distributed learning network. Initial radiomics work is underway. Results: For the NSCLC pilot, 159/419 patient datasets were identified meeting the PM criteria, and hence eligible for inclusion in the curative clinical cohort (for the larynx pilot, 109/125). Some missing data were imputed using Bayesian methods. For both, the European PMs successfully predicted prognosis groups, but with some differences in practice reflected. For example, the PM-predicted good prognosis NSCLC group was differentiated from a combined medium/poor prognosis group (2YOS 69% vs. 27%, p<0.001). Stage was less discriminatory in identifying prognostic groups. In the good prognosis group two-year overall survival was 65% in curatively and 18% in palliatively treated patients. Conclusion: The technical infrastructure and basic European PMs support prognosis prediction for these Australian patient groups, showing promise for supporting future personalized treatment decisions

  18. Rapid characterisation and identification of compounds in Saposhnikoviae Radix by high-performance liquid chromatography coupled with electrospray ionisation quadrupole time-of-flight mass spectrometry.

    Science.gov (United States)

    Chen, Luxiao; Chen, Xiangyang; Su, Lei; Jiang, Yanyan; Liu, Bin

    2017-08-18

    Saposhnikoviae Radix (SR), the dried root of Saposhnikovia divaricata (Turcz.) Schischk. (Umbelliferae), is commonly used as a traditional Chinese medicine. In this study, a rapid and accurate method was firstly, developed for the qualitative analysis of SR by high-performance liquid chromatography coupled with electrospray ionisation quadrupole time-of-flight mass spectrometry (HPLC-ESI-Q-TOF-MS/MS). A total of 45 compounds were identified or tentatively characterised, including 13 chromones, 28 coumarins and four others. Among them, 16 compounds were identified from SR for the first time. In addition, six chromones reference standards, including two isolated compounds of 3'-O-angeloylhamaudol and norcimifugin from the extraction of SR, were used to study the fragmentation pathways of chromones. The developed method was effective for characterising the compounds of SR, and the results of the study enriched the understanding of the chemical connotation.

  19. Bead Injection Extraction Chromatography using High-capacity Lab-on-Valve as a Front End to Inductively Coupled Plasma Mass Spectrometry for Rapid Urine Radiobioassay

    DEFF Research Database (Denmark)

    Qiao, Jixin; Hou, Xiaolin; Roos, Per

    2013-01-01

    A novel bead injection (BI) extraction chromatographic microflow system exploiting high-capacity lab-on-valve (LOV) platform coupled with inductively coupled plasma mass spectrometric detection is developed for rapid and automated determination of plutonium in human urine. A microconduit (1 m......L) incorporated within the LOV processing unit is loaded on-line with a metered amount of disposable extraction chromatographic resin (up to 330 mg of TEVA) through programmable beads transport. Selective capture and purification of plutonium onto the resin beads is then performed by pressure driven flow after.......319 ± 0.004 g, n=5). The chemical yields of plutonium were averagely better than 90% under the optimal experimental conditions and the entire analytical procedure could be accomplished within a short timeframe (

  20. Rapid determination of the binding affinity and specificity of the mushroom Polyporus squamosus lectin using frontal affinity chromatography coupled to electrospray mass spectrometry.

    Science.gov (United States)

    Zhang, B; Palcic, M M; Mo, H; Goldstein, I J; Hindsgaul, O

    2001-02-01

    The binding affinity and specificity of the mushroom Polyporus squamosus lectin has been determined by the recently developed method of frontal affinity chromatography coupled to electrospray mass spectrometry (FAC/MS). A micro-scale affinity column was prepared by immobilizing the lectin ( approximately 25 microg) onto porous glass beads in a tubing column (9.8 microl column volume). The column was then used to screen several oligosaccharide mixtures. The dissociation constants of 22 sialylated or sulfated oligosaccharides were evaluated against the immobilized lectin. The lectin was found to be highly specific for Neu5Acalpha2-6Galbeta1-4Glc/GlcNAc containing oligosaccharides with K(d) values near 10 microM. The FAC/MS assay permits the rapid determination of the dissociation constants of ligands as well as a higher throughput screening of compound mixtures, making it a valuable tool for affinity studies, especially for testing large numbers of compounds.

  1. Rapid development of sensitive, high-throughput, quantitative and highly selective mass spectrometric targeted immunoassays for clinically important proteins in human plasma and serum

    Science.gov (United States)

    Krastins, Bryan; Prakash, Amol; Sarracino, David A.; Nedelkov, Dobrin; Niederkofler, Eric E.; Kiernan, Urban A.; Nelson, Randall; Vogelsang, Maryann S.; Vadali, Gouri; Garces, Alejandra; Sutton, Jennifer N.; Peterman, Scott; Byram, Gregory; Darbouret, Bruno; Pérusse, Joëlle R.; Seidah, Nabil G.; Coulombe, Benoit; Gobom, Johan; Portelius, Erik; Pannee, Josef; Blennow, Kaj; Kulasingam, Vathany; Couchman, Lewis; Moniz, Caje; Lopez, Mary F.

    2013-01-01

    Objectives The aim of this study was to develop high-throughput, quantitative and highly selective mass spectrometric, targeted immunoassays for clinically important proteins in human plasma or serum. Design and methods The described method coupled mass spectrometric immunoassay (MSIA), a previously developed technique for immunoenrichment on a monolithic microcolumn activated with an anti-protein antibody and fixed in a pipette tip, to selected reaction monitoring (SRM) detection and accurate quantification of targeted peptides, including clinically relevant sequence or truncated variants. Results In this report, we demonstrate the rapid development of MSIA-SRM assays for sixteen different target proteins spanning seven different clinically important areas (including neurological, Alzheimer's, cardiovascular, endocrine function, cancer and other diseases) and ranging in concentration from pg/mL to mg/mL. The reported MSIA-SRM assays demonstrated high sensitivity (within published clinical ranges), precision, robustness and high-throughput as well as specific detection of clinically relevant isoforms for many of the target proteins. Most of the assays were tested with bona-fide clinical samples. In addition, positive correlations, (R2 0.67–0.87, depending on the target peptide), were demonstrated for MSIA-SRM assay data with clinical analyzer measurements of parathyroid hormone (PTH) and insulin growth factor 1 (IGF1) in clinical sample cohorts. Conclusions We have presented a practical and scalable method for rapid development and deployment of MS-based SRM assays for clinically relevant proteins and measured levels of the target analytes in bona fide clinical samples. The method permits the specific quantification of individual protein isoforms and addresses the difficult problem of protein heterogeneity in clinical proteomics applications. PMID:23313081

  2. A novel tandem mass spectrometry method for rapid confirmation of medium- and very long-chain acyl-CoA dehydrogenase deficiency in newborns.

    Directory of Open Access Journals (Sweden)

    Frank ter Veld

    Full Text Available BACKGROUND: Newborn screening for medium- and very long-chain acyl-CoA dehydrogenase (MCAD and VLCAD, respectively deficiency, using acylcarnitine profiling with tandem mass spectrometry, has increased the number of patients with fatty acid oxidation disorders due to the identification of additional milder, and so far silent, phenotypes. However, especially for VLCADD, the acylcarnitine profile can not constitute the sole parameter in order to reliably confirm disease. Therefore, we developed a new liquid chromatography tandem mass spectrometry (LC-MS/MS method to rapidly determine both MCAD- and/or VLCAD-activity in human lymphocytes in order to confirm diagnosis. METHODOLOGY: LC-MS/MS was used to measure MCAD- or VLCAD-catalyzed production of enoyl-CoA and hydroxyacyl-CoA, in human lymphocytes. PRINCIPAL FINDINGS: VLCAD activity in controls was 6.95+/-0.42 mU/mg (range 1.95 to 11.91 mU/mg. Residual VLCAD activity of 4 patients with confirmed VLCAD-deficiency was between 0.3 and 1.1%. Heterozygous ACADVL mutation carriers showed residual VLCAD activities of 23.7 to 54.2%. MCAD activity in controls was 2.38+/-0.18 mU/mg. In total, 28 patients with suspected MCAD-deficiency were assayed. Nearly all patients with residual MCAD activities below 2.5% were homozygous 985A>G carriers. MCAD-deficient patients with one other than the 985A>G mutation had higher MCAD residual activities, ranging from 5.7 to 13.9%. All patients with the 199T>C mutation had residual activities above 10%. CONCLUSIONS: Our newly developed LC-MS/MS method is able to provide ample sensitivity to correctly and rapidly determine MCAD and VLCAD residual activity in human lymphocytes. Importantly, based on measured MCAD residual activities in correlation with genotype, new insights were obtained on the expected clinical phenotype.

  3. [Rapid screening of fipronil and its metabolites in egg and egg products by solid phase extraction-liquid chromatography-quadrupole time-of-flight mass spectrometry].

    Science.gov (United States)

    Guo, Dehua; Shi, Yiyin; Li, You; Yi, Xionghai; Deng, Xiaojun; Xiao, Wenqing; Wang, Jian; Li, Xiao; Liu, Han; Shen, Weijian

    2017-12-08

    A method for rapid screening of fipronil and its metabolites in egg and egg products was developed by liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (LC-QTOF MS). The samples were extracted by acid-acetonitrile, cleaned up by PRiME HLB SPE. The separation was performed on a Poroshell 120 EC C18 column (150 mm×3 mm, 2.7 μm) with gradient elution using water and acetonitrile as mobile phases. The target compounds were monitored under negative ionization mode with electrospray ionization (ESI) source and two databases of accurate mass and fragment ions were created. The matrix effects in four kinds of egg and egg products were considered and the quantification was carried out by internal standard method. The results demonstrated that the linear ranges were from 0.1 to 5 μg/L with good correlation coefficients (r2>0.99). The limits of detection (LODs, S/N>3) and limits of quantitation (LOQs, S/N>10) were 0.2 μg/kg and 1 μg/kg, respectively. The recoveries of fipronil and its metabolites in different matrixes spiked with 1, 2 and 5 μg/kg varied from 82.6%-98.1%, and the relative standard deviations (RSDs) were between 3.8%-9.9% (n=6). The method can effectively correct the ionization suppression. It is sensitive, accurate and suitable for the rapid screening of fipronil, fipronil sulfide, fipronil sulfone and fipronil desulfinyl in egg, egg noodle, cake and mayonnaise.

  4. Rapid and High-Throughput Detection and Quantitation of Radiation Biomarkers in Human and Nonhuman Primates by Differential Mobility Spectrometry-Mass Spectrometry.

    Science.gov (United States)

    Chen, Zhidan; Coy, Stephen L; Pannkuk, Evan L; Laiakis, Evagelia C; Hall, Adam B; Fornace, Albert J; Vouros, Paul

    2016-10-01

    Radiation exposure is an important public health issue due to a range of accidental and intentional threats. Prompt and effective large-scale screening and appropriate use of medical countermeasures (MCM) to mitigate radiation injury requires rapid methods for determining the radiation dose. In a number of studies, metabolomics has identified small-molecule biomarkers responding to the radiation dose. Differential mobility spectrometry-mass spectrometry (DMS-MS) has been used for similar compounds for high-throughput small-molecule detection and quantitation. In this study, we show that DMS-MS can detect and quantify two radiation biomarkers, trimethyl-L-lysine (TML) and hypoxanthine. Hypoxanthine is a human and nonhuman primate (NHP) radiation biomarker and metabolic intermediate, whereas TML is a radiation biomarker in humans but not in NHP, which is involved in carnitine synthesis. They have been analyzed by DMS-MS from urine samples after a simple strong cation exchange-solid phase extraction (SCX-SPE). The dramatic suppression of background and chemical noise provided by DMS-MS results in an approximately 10-fold reduction in time, including sample pretreatment time, compared with liquid chromatography-mass spectrometry (LC-MS). DMS-MS quantitation accuracy has been verified by validation testing for each biomarker. Human samples are not yet available, but for hypoxanthine, selected NHP urine samples (pre- and 7-d-post 10 Gy exposure) were analyzed, resulting in a mean change in concentration essentially identical to that obtained by LC-MS (fold-change 2.76 versus 2.59). These results confirm the potential of DMS-MS for field or clinical first-level rapid screening for radiation exposure. Graphical Abstract ᅟ.

  5. A simple method for rapid microbial identification from positive monomicrobial blood culture bottles through matrix-assisted laser desorption ionization time-of-flight mass spectrometry.

    Science.gov (United States)

    Lin, Jung-Fu; Ge, Mao-Cheng; Liu, Tsui-Ping; Chang, Shih-Cheng; Lu, Jang-Jih

    2017-06-30

    Rapid identification of microbes in the bloodstream is crucial in managing septicemia because of its high disease severity, and direct identification from positive blood culture bottles through matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) can shorten the turnaround time. Therefore, we developed a simple method for rapid microbiological identification from positive blood cultures by using MALDI-TOF MS. We modified previously developed methods to propose a faster, simpler and more economical method, which includes centrifugation and hemolysis. Specifically, our method comprises two-stage centrifugation with gravitational acceleration (g) at 600g and 3000g, followed by the addition of a lysis buffer and another 3000g centrifugation. In total, 324 monomicrobial bacterial cultures were identified. The success rate of species identification was 81.8%, which is comparable with other complex methods. The identification success rate was the highest for Gram-negative aerobes (85%), followed by Gram-positive aerobes (78.2%) and anaerobes (67%). The proposed method requires less than 10 min, costs less than US$0.2 per usage, and facilitates batch processing. We conclude that this method is feasible for clinical use in microbiology laboratories, and can serve as a reference for treatments or further complementary diagnostic testing. Copyright © 2017. Published by Elsevier B.V.

  6. Rapid identification of Enterobacteriaceae in milk and dairy products with the Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry (MALDI-TOF MS

    Directory of Open Access Journals (Sweden)

    Miroslava Kačániová

    2017-11-01

    Full Text Available Identification of microorganisms by MALDI-TOF MS Biotyper has been demonstrated to be accurate, rapid and lower cost than conventional food investigation methods. Rapid identification of pathogenic and spoilage microorganisms is crucial for dairy industry to ensure the quality and safety of milk and milk products. In this study, the bacterial species representing the Enterobacteriaceae family were identified in raw milk and milk products using the MALDI-TOF MS mass spectrometry. Altogether, 20 samples of Slovak milk and milk products were examined. Samples were cultured on VRBG agar at 37 °C for 24-48 h. Typical bacterial colonies were selected for identification with MALDI-TOF MS Biotyper. Escherichia coli and Enterobacter sp. were the most abundant  Enterobacteriaceae family representatives identified. E. coli was found in nine  and Enterobacter sp. in eight samples. Enterobacter sp. comprised 49 % and Escherichia coli 23 % of all bacterial isolates. The study shows that MALDI-TOF MS Biotyper was reliable identification method of Enterobacteriaceae in milk and dairy products. This method was helpful in evaluation of bacterial contamination of milk.

  7. Rapid determination of yunaconitine and related alkaloids in aconites and aconite-containing drugs by ultra high-performance liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Song, Long; Zhang, Hong; Liu, Xin; Zhao, Zhi-Li; Chen, Shi-Lin; Wang, Zheng-Tao; Xu, Hong-Xi

    2012-12-01

    Yunaconitine (YAC) is a toxic aconite alkaloid that is considered to be a hidden aconite poison since it is frequently found in body fluids from aconite poisoning patients, but has not been well studied in commonly used herbal drugs. In this paper, a rapid and sensitive ultra high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) detection combined with microwave-assisted extraction (MAE) was developed for high throughput simultaneous determination of YAC and six other toxic aconite alkaloids in 31 samples of crude, processed aconites and aconite-containing drugs. The optimized method showed excellent linearity, precision, accuracy and recovery for all target compounds with short run time. YAC was detected in some samples with contents from 0.015 to 10.41 mg/g. This is the first report on the determination of YAC in Radix Aconiti, Radix Aconiti Kusnezoffii and aconite-containing drugs. This newly developed method facilitates the rapid screening of YAC and related toxic aconite alkaloids and allows YAC to be used as a chemical marker for the quality control of aconites and aconite-containing drugs. Copyright © 2012 John Wiley & Sons, Ltd.

  8. Rapid detection by direct analysis in real time-mass spectrometry (DART-MS) of psychoactive plant drugs of abuse: the case of Mitragyna speciosa aka "Kratom".

    Science.gov (United States)

    Lesiak, Ashton D; Cody, Robert B; Dane, A John; Musah, Rabi A

    2014-09-01

    Mitragyna speciosa, also known commonly as "Kratom" or "Ketum", is a plant with psychoactive properties that have been attributed to the presence of various indole alkaloids such as mitragynine and 7-hydroxymitragynine. M. speciosa use is gaining popularity internationally as a natural and legal alternative to narcotics. As a drug of abuse, its detection and identification are not straightforward, since M. speciosa plant material is not particularly distinctive. Here, we show that direct analysis in real time-mass spectrometry (DART-MS) can be used not only to rapidly identify M. speciosa plant material and distinguish it from other plants, but also to distinguish between M. speciosa plant varieties, based on differences between their chemical profiles. The method is rapid and the analysis expeditious. Plant material such as that found at a crime scene can be analyzed directly with no sample pre-preparation steps. Furthermore, we show that the basis set of principal components that permit characterization of the plant material can be used to positively identify M. speciosa. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  9. Rapid speciation of iron by on-line coupling of short column capillary electrophoresis and inductively coupled plasma mass spectrometry with the collision cell technique.

    Science.gov (United States)

    Li, Bao-Hui; Yan, Xiu-Ping

    2007-04-01

    A method for rapid speciation analysis of iron was developed by on-line coupling of short column capillary electrophoresis and inductively coupled plasma mass spectrometry. The collision cell technique was used to eliminate argon-based polyatomic interferences and a Micromist nebulizer was employed to increase the nebulization efficiency. Rapid speciation analysis of Fe(II) and Fe(III) was achieved within 1 min by short column capillary electrophoresis in a 14 cm x 50 microm id capillary at 28 kV voltage with a mixture of 15 mmol/L tris(hydroxymethyl)aminomethane + 1 mmol/L 1,10-phenanthroline + 1 mmol/L EDTA (pH 8.6) as running electrolyte. The precisions (RSD, n = 5) of migration time and peak area for Fe(II) and Fe(III) were in the range of 1.0 - 2.6 and 1.9 - 3.9%, respectively. The limits of detection (3sigma) of Fe(II) and Fe(III) were 10.0 and 8.3 microg/L, respectively.

  10. Rapid determination of 4-aminobutyric acid and L-glutamic acid in biological decarboxylation process by capillary electrophoresis-mass spectrometry.

    Science.gov (United States)

    Takeda, Sahori; Yamano, Naoko; Kawasaki, Norioki; Ando, Hisanori; Nakayama, Atsuyoshi

    2012-01-01

    4-Aminobutylic acid (GABA) is a monomer of plastic polyamide 4. Bio-based polyamide 4 can be produced by using GABA obtained from biomass. The production of L-glutamic acid (Glu) from biomass has been established. GABA is produced by decarboxylation of Glu in biological process. High-performance liquid chromatography (HPLC) with derivatization is generally used to determine the concentration of GABA and Glu in reacted solution samples for the efficient production of GABA. In this study, we have investigated the rapid determination of GABA and Glu by capillary electrophoresis-mass spectrometry (CE-MS) without derivatization. The determination was achieved with the use of a shortened capillary, a new internal standard for GABA, and optimization of sheath liquid composition. Determined concentrations of GABA and Glu by CE-MS were compared with those by pre-column derivatization HPLC with phenylisothiocyanate. The determined values by CE-MS were close to those by HPLC with pre-column derivatization. These results suggest that the determination of GABA and Glu in reacted solution is rapid and simplified by the use of CE-MS. Copyright © 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Rapid identification of clinical mycobacterial isolates by protein profiling using matrix assisted laser desorption ionization-time of flight mass spectrometry.

    Science.gov (United States)

    Panda, A; Kurapati, S; Samantaray, J C; Myneedu, V P; Verma, A; Srinivasan, A; Ahmad, H; Behera, D; Singh, U B

    2013-01-01

    The purpose of this study was to evaluate the identification of Mycobacterium tuberculosis which is often plagued with ambiguity. It is a time consuming process requiring 4-8 weeks after culture positivity, thereby delaying therapeutic intervention. For a successful treatment and disease management, timely diagnosis is imperative. We evaluated a rapid, proteomic based technique for identification of clinical mycobacterial isolates by protein profiling using matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). Freshly grown mycobacterial isolates were used. Acetonitrile/trifluoroacetic acid extraction procedure was carried out, following which cinnamic acid charged plates were subjected to identification by MALDI-TOF MS. A comparative analysis of 42 clinical mycobacterial isolates using the MALDI-TOF MS and conventional techniques was carried out. Among these, 97.61% were found to corroborate with the standard methods at genus level and 85.36% were accurate till the species level. One out of 42 was not in accord with the conventional assays because MALDI-TOF MS established it as Mycobacterium tuberculosis (log (score)>2.0) and conventional methods established it to be non-tuberculous Mycobacterium. MALDI-TOF MS was found to be an accurate, rapid, cost effective and robust system for identification of mycobacterial species. This innovative approach holds promise for early therapeutic intervention leading to better patient care.

  12. Assessing direct analysis in real-time-mass spectrometry (DART-MS) for the rapid identification of additives in food packaging.

    Science.gov (United States)

    Ackerman, L K; Noonan, G O; Begley, T H

    2009-12-01

    The ambient ionization technique direct analysis in real time (DART) was characterized and evaluated for the screening of food packaging for the presence of packaging additives using a benchtop mass spectrometer (MS). Approximate optimum conditions were determined for 13 common food-packaging additives, including plasticizers, anti-oxidants, colorants, grease-proofers, and ultraviolet light stabilizers. Method sensitivity and linearity were evaluated using solutions and characterized polymer samples. Additionally, the response of a model additive (di-ethyl-hexyl-phthalate) was examined across a range of sample positions, DART, and MS conditions (temperature, voltage and helium flow). Under optimal conditions, molecular ion (M+H+) was the major ion for most additives. Additive responses were highly sensitive to sample and DART source orientation, as well as to DART flow rates, temperatures, and MS inlet voltages, respectively. DART-MS response was neither consistently linear nor quantitative in this setting, and sensitivity varied by additive. All additives studied were rapidly identified in multiple food-packaging materials by DART-MS/MS, suggesting this technique can be used to screen food packaging rapidly. However, method sensitivity and quantitation requires further study and improvement.

  13. Rapid screening and quantification of residual pesticides and illegal adulterants in red wine by direct analysis in real time mass spectrometry.

    Science.gov (United States)

    Guo, Tianyang; Fang, Pingping; Jiang, Juanjuan; Zhang, Feng; Yong, Wei; Liu, Jiahui; Dong, Yiyang

    2016-11-04

    A rapid method to screen and quantify multi-class analytic targets in red wine has been developed by direct analysis in real time (DART) coupled with triple quadruple tandem mass spectrometry (QqQ-MS). A modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) procedure was used for increasing analytical speed and reducing matrix effect, and the multiple reaction monitoring (MRM) in DART-MS/MS ensured accurate analysis. One bottle of wine containing 50 pesticides and 12 adulterants, i.e., preservatives, antioxidant, sweeteners, and azo dyes, could be totally determined less than 12min. This method exhibited proper linearity (R2≥0.99) in the range of 1-1000ng/mL for pesticides and 10-5000ng/mL for adulterants. The limits of detection (LODs) were obtained in a 0.5-50ng/mL range for pesticides and 5-50ng/mL range for adulterants, and the limits of quantification (LOQs) were in a 1-100ng/mL range for pesticides and 10-250ng/mL range for adulterants. Three spiked levels for each analyte in wine were evaluated, and the recoveries were in a scope of 75-120%. The results demonstrated DART-MS/MS was a rapid and simple method, and could be applied to rapid analyze residual pesticides and illegal adulterants in a large quantities of red wine. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Galaxy And Mass Assembly: automatic morphological classification of galaxies using statistical learning

    Science.gov (United States)

    Sreejith, Sreevarsha; Pereverzyev, Sergiy, Jr.; Kelvin, Lee S.; Marleau, Francine R.; Haltmeier, Markus; Ebner, Judith; Bland-Hawthorn, Joss; Driver, Simon P.; Graham, Alister W.; Holwerda, Benne W.; Hopkins, Andrew M.; Liske, Jochen; Loveday, Jon; Moffett, Amanda J.; Pimbblet, Kevin A.; Taylor, Edward N.; Wang, Lingyu; Wright, Angus H.

    2018-03-01

    We apply four statistical learning methods to a sample of 7941 galaxies (z galaxies. Using 10 features measured for each galaxy (sizes, colours, shape parameters, and stellar mass), we apply the techniques of Support Vector Machines, Classification Trees, Classification Trees with Random Forest (CTRF) and Neural Networks, and returning True Prediction Ratios (TPRs) of 75.8 per cent, 69.0 per cent, 76.2 per cent, and 76.0 per cent, respectively. Those occasions whereby all four algorithms agree with each other yet disagree with the visual classification (`unanimous disagreement') serves as a potential indicator of human error in classification, occurring in ˜ 9 per cent of ellipticals, ˜ 9 per cent of little blue spheroids, ˜ 14 per cent of early-type spirals, ˜ 21 per cent of intermediate-type spirals, and ˜ 4 per cent of late-type spirals and irregulars. We observe that the choice of parameters rather than that of algorithms is more crucial in determining classification accuracy. Due to its simplicity in formulation and implementation, we recommend the CTRF algorithm for classifying future galaxy data sets. Adopting the CTRF algorithm, the TPRs of the five galaxy types are : E, 70.1 per cent; LBS, 75.6 per cent; S0-Sa, 63.6 per cent; Sab-Scd, 56.4 per cent, and Sd-Irr, 88.9 per cent. Further, we train a binary classifier using this CTRF algorithm that divides galaxies into spheroid-dominated (E, LBS, and S0-Sa) and disc-dominated (Sab-Scd and Sd-Irr), achieving an overall accuracy of 89.8 per cent. This translates into an accuracy of 84.9 per cent for spheroid-dominated systems and 92.5 per cent for disc-dominated systems.

  15. Principle component analysis combined with matrix-assisted laser desorption ionization mass spectrometry for rapid diagnosing the sera of patients with major depression.

    Science.gov (United States)

    Huang, Tiao-Lai; Cho, Yi-Tzu; Su, Hong; Shiea, Jentaie

    2013-09-23

    Previously, we demonstrated that 6M HCl hydrolysis followed by matrix-assisted laser desorption/ionization (MALDI-TOF) mass spectrometry is a useful technique to detect potential protein biomarkers in the sera collected from major depression (MD) patients and from healthy controls. In this study, the effects of various organic acids in hydrolyzing proteins in serum were first examined. The organic matrixes commonly used in MALDI analysis were also examined for characterizing the hydrolyzed peptides. Finally, principle component analysis (PCA) was used to analyze the MALDI mass spectra of acid-hydrolyzed serum samples. It was found that 20% TFA and sinapinic acid were the optimal reagents for hydrolysis and MALDI matrix. Samples collected from MD patients and healthy controls were readily classified through PCA analysis. A receiver operating characteristic (ROC) curve based on the ratio of the intensities of the two fragment ions (m/z 8606 and 9287) indicated by PCA plot was also constructed. The area under the curve was 0.845; the sensitivity and specificity were both 80%. An analytical platform employing trifluoroacetic acid to hydrolyze serum proteins followed by MALDI-TOF/MS and PCA analysis was developed to rapidly differentiate the sera between MD patients and healthy controls. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. Rapid Spread of Zika Virus in The Americas - Implications for Public Health Preparedness for Mass Gatherings at the 2016 Brazil Olympic Games

    Directory of Open Access Journals (Sweden)

    Eskild Petersen

    2016-03-01

    Full Text Available Mass gatherings at major international sporting events put millions of international travelers and local host-country residents at risk of acquiring infectious diseases, including locally endemic infectious diseases. The mosquito-borne Zika virus (ZIKV has recently aroused global attention due to its rapid spread since its first detection in May 2015 in Brazil to 22 other countries and other territories in the Americas. The ZIKV outbreak in Brazil, has also been associated with a significant rise in the number of babies born with microcephaly and neurological disorders, and has been declared a ‘Global Emergency by the World Health Organization. This explosive spread of ZIKV in Brazil poses challenges for public health preparedness and surveillance for the Olympics and Paralympics which are due to be held in Rio De Janeiro in August, 2016. We review the epidemiology and clinical features of the current ZIKV outbreak in Brazil, highlight knowledge gaps, and review the public health implications of the current ZIKV outbreak in the Americas. We highlight the urgent need for a coordinated collaborative response for prevention and spread of infectious diseases with epidemic potential at mass gatherings events.

  17. A rapid and sensitive liquid chromatography–tandem mass spectrometric method for the determination of hederasaponin B in rat plasma: Application to a pharmacokinetic study

    Directory of Open Access Journals (Sweden)

    Jiaxin Liu

    2017-07-01

    Full Text Available A rapid, simple and sensitive ultra-high performance liquid chromatography–tandem mass spectrometric (UPLC–MS/MS method was developed and validated for the determination of hederasaponin B, an active triterpenoid saponin widely existed in Hedera helix L. Plasma samples were processed by protein precipitation with acetonitrile and separated on a Thermo Hypersil GOLD C18 (2.1 mm × 50 mm,1.9 µm at flow rate of 0.3 ml/min, with a gradient elution consisting of acetonitrile and water containing 0.1% (v/v formic acid at 30 °C and detected by electrospray ionization mass spectrometry in the positive multiple reaction monitoring (MRM mode. The linearity was found to be within the concentration range of 0.5–5000 ng/ml with a lower limit of quantification of 0.5 ng/ml. The absolute oral bioavailability of hederasaponin B was 0.24 ± 0.49%. This indicated that the concentration-time course of the hederasaponin B existed a double-peak phenomenon. This method was further applied to the determination of hederasaponin B in rat plasma and showed good practicability, for the first time, after intragastric (25 mg/kg and intravenous (2 mg/kg administration in rats.

  18. Rapid determination of amino acids in fruits of Ziziphus jujuba by hydrophilic interaction ultra-high-performance liquid chromatography coupled with triple-quadrupole mass spectrometry.

    Science.gov (United States)

    Guo, Sheng; Duan, Jin-ao; Qian, Dawei; Tang, Yuping; Qian, Yefei; Wu, Dawei; Su, Shulan; Shang, Erxin

    2013-03-20

    In this study, a sensitive and rapid method for the simultaneous determination of free amino acids without derivatization using hydrophilic interaction liquid chromatography coupled with tandem mass spectrometry (HILIC-MS/MS) was developed. The method was performed on an ultra-high-performance liquid chromatography (UHPLC) separation system coupled with a triple-quadrupole mass spectrometry (TQ-MS) instrument. Sufficient separation of 23 underivatized amino acids was achieved on an Acquity BEH Amide column (2.1 mm × 100 mm, 1.7 μm) in a single run of 12 min. Then the method was applied for the analysis of the free amino acids in 46 batches of Ziziphus jujuba fruits which comprised 39 cultivars from 26 cultivation regions. Multivariate statistical analysis was also used to investigate the differences in free amino acid profiles among the samples. This study showed that HILIC-UHPLC-TQ-MS is an effective technique to analyze underivatized amino acids in the food samples.

  19. Development of a rapid screening method to determine primary aromatic amines in kitchen utensils using direct analysis in real time mass spectrometry (DART-MS).

    Science.gov (United States)

    Paseiro-Cerrato, R; Noonan, G O; Begley, T H

    2014-01-01

    Primary aromatic amines (PAAs) are a group of substances with undesirable health effects, that are used in a variety of commercial products. Several recent studies, using a number of screening and confirmatory methods, have reported the migration of PAAs from some kitchen utensils into acetic acid 3% (w/v). Many of these methods require significant sample preparation, therefore the aim of this work was to determine if direct analysis in real time mass spectrometry (DART-MS) could be utilised as a rapid screening tool for the determination of PAAs in kitchen utensils. DART-MS results from direct analysis of the utensil have been compared with results of PAA migration by ultra high performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method. The UPLC-MS/MS method had excellent linearity, appropriate sensitivity (LOD ≤ 1.5 µg L(-1); LOQ ≤ 4.5 µg L(-1)), repeatability from 2.4 to 13.2% and acceptable recoveries. DART-MS results were in good agreement with UPLC-MS/MS data, with 100% of non-compliant (PAA positive) samples successfully identified by DART-MS.

  20. An integrated strategy for rapid discovery and identification of the sequential piperine metabolites in rats using ultra high-performance liquid chromatography/high resolution mass spectrometery.

    Science.gov (United States)

    Shang, Zhanpeng; Cai, Wei; Cao, Yanfeng; Wang, Fei; Wang, Zhibin; Lu, Jianqiu; Zhang, Jiayu

    2017-11-30

    Piperine, one of the major bioactive constituents isolated from natural flavorings and medicinal-culinary herbs, possesses various biological activities. In the present study, an integrated strategy based on ultra high-performance liquid chromatography/high resolution mass spectrometry was established to reveal piperine metabolism in rats. First of all, post-acquisition data-mining methods, including high resolution extracted ion chromatograms (HREICs) and multiple mass defect filtering (MMDF), were used to screen piperine metabolite candidates in a full-scan HRMS(1) level. Then, parent ion list-dynamic exclusion coupled with data-dependent data-acquisition method was utilized to acquire MS(n) datasets. In addition, the established reverse molecular assembly (RMA) approach based on paired diagnostic product ions (pDPIs) coupled with neutral loss fragments (NLFs) was used to ascertain and identify the major-to-trace piperine metabolites efficiently. And then, the calculated ClogP values were utilized to distinguish the positional isomers. As a result, a total of 148 piperine metabolites were detected and characterized tentatively. The results demonstrated that piperine mainly underwent hydrogenation, dehydrogenation, hydroxylation, glucuronide conjugation, sulfate conjugation, ring-cleavage, and their composite reactions. Our results not only provided novel and useful data to better understand the safety, toxicity and efficacy of this potential therapeutic agent, but also indicated that the proposed strategy was reliable for a rapid discovery and identification drug-related constituents in vivo. Copyright © 2017. Published by Elsevier B.V.

  1. A differential mobility spectrometry/mass spectrometry platform for the rapid detection and quantitation of DNA adduct dG-ABP.

    Science.gov (United States)

    Kafle, Amol; Klaene, Joshua; Hall, Adam B; Glick, James; Coy, Stephen L; Vouros, Paul

    2013-07-15

    There is continued interest in exploring new analytical technologies for the detection and quantitation of DNA adducts, biomarkers which provide direct evidence of exposure and genetic damage in cells. With the goal of reducing clean-up steps and improving sample throughput, a Differential Mobility Spectrometry/Mass Spectrometry (DMS/MS) platform has been introduced for adduct analysis. A DMS/MS platform has been utilized for the analysis of dG-ABP, the deoxyguanosine adduct of the bladder carcinogen 4-aminobiphenyl (4-ABP). After optimization of the DMS parameters, each sample was analyzed in just 30 s following a simple protein precipitation step of the digested DNA. A detection limit of one modification in 10^6 nucleosides has been achieved using only 2 µg of DNA. A brief comparison (quantitative and qualitative) with liquid chromatography/mass spectrometry is also presented highlighting the advantages of using the DMS/MS method as a high-throughput platform. The data presented demonstrate the successful application of a DMS/MS/MS platform for the rapid quantitation of DNA adducts using, as a model analyte, the deoxyguanosine adduct of the bladder carcinogen 4-aminobiphenyl. Copyright © 2013 John Wiley & Sons, Ltd.

  2. Rapid separation and identification of phenolics in crude red grape skin extracts by high performance liquid chromatography coupled to diode array detection and tandem mass spectrometry.

    Science.gov (United States)

    Ji, Mei; Li, Chen; Li, Qiang

    2015-10-02

    A rapid and efficient method was established for the simultaneous determination of structures and configurations for 45 phenolics isolated from crude red grape skin extracts without extensive sample preparation. Separation and compound assignments were achieved using high performance liquid chromatography coupled to diode array detection and tandem mass spectrometry (HPLC-DAD-MS(2)). A Poroshell 120 EC-C18 (100mm×3.0mm, 2.7μm) column was employed to separate the phenolics, which were eluted using a gradient of acetonitrile and water acidified with 0.2% formic acid. Phenolics were identified by comparison of their UV-vis spectra, mass spectra and MS(2) data with those in the literature. Using this procedure, five compounds were detected for the first time in Vitis amurensis. Good separation of most phenolics was achieved in 26min. The methods described here can be used for the characterization of phenolics in a variety of grapes and grape products. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Rapid comprehensive amino acid analysis by liquid chromatography/tandem mass spectrometry: comparison to cation exchange with post-column ninhydrin detection.

    Science.gov (United States)

    Dietzen, Dennis J; Weindel, Annette L; Carayannopoulos, Mary O; Landt, Michael; Normansell, Ellen T; Reimschisel, Tyler E; Smith, Carl H

    2008-11-01

    Ion-exchange chromatography with ninhydrin detection remains the gold standard for detecting inborn errors of amino acid catabolism and transport. Disadvantages of such analysis include long chromatography times and interference from other ninhydrin-positive compounds. The aim of this project was to develop a more rapid and specific technique using liquid chromatography/tandem mass spectrometry (LC/MS/MS). Optimal fragmentation patterns for 32 amino acids were determined on a triple quadrupole mass spectrometer following butylation. Chromatographic characteristics of each of the amino acids were determined using C8 reversed-phase chromatography with 20% acetonitrile/0.1% formic acid as isocratic mobile phase. Quantitation using eleven deuterated internal standards was compared to cation exchange and ninhydrin detection on a Beckman 7300 system. Following methanol extraction and butylation, determination of 32 amino acids required 20 min. The dynamic range of each amino acid was generally 1-1000 micromol/L. Imprecision ranged from 7 to 23% (CV) over 6 months and recovery ranged from 88-125%. Deming regression with the Beckman 7300 yielded slopes from 0.4-1.2, intercepts from -21 to 65 micromol/L, correlation coefficients from 0.84-0.99 and Syx from 2-125 micromol/L. Isobaric amino acids were separated by chromatography (e.g. leucine, isoleucine) or by unique fragmentation (e.g., alanine, beta-alanine). LC/MS/MS is comparable to traditional LC-ninhydrin detection. Mass spectral detection shortens analysis times and reduces potential for interference in detecting inborn metabolic errors.

  4. Rapid assessment of tsunami impact from real-time seismology and geographic, historical other datasets using machine learning

    Science.gov (United States)

    Michelini, Alberto; Lomax, Anthony

    2017-04-01

    The impact of an earthquake, tsunami, volcanic eruption, severe weather or other natural disaster is related to: the intensity of the hazard; the vulnerability or exposure of the population, such as housing quality, infrastructure and proximity to a coastlines; and the capacity to resist and cope with the disaster. Rapid assessment by monitoring agencies of the impact of a natural event is fundamental for early warning and response. We previously* proposed the "tsunami importance" parameter, It, for characterizing the strength of a tsunami. This parameter combines 5 descriptive indices from the NOAA/WDC Historical Tsunami Database: 4 tsunami impact measures (deaths, injuries, damage, houses destroyed), and maximum water height. Accordingly, It = 2 corresponds approximately to the JMA threshold for issuing a ''Tsunami Warning'' whereas the largest or most devastating tsunamis typically have It = 10. Here we discuss extending this simple, 5-component parameter with additional impact-related measures from relevant databases (e.g., LandScan population density, major infrastructures) and historical / archaeological information, and measures that might be obtained in near-real-time (e.g., emergency services, news, social media). We combine these measures with seismological and other real-time observations as an ensemble of features within automated procedures to estimate impact and guide decision making. We examine using modern machine learning methodologies to train and calibrate the procedures, while working with high-dimensional feature space. * Lomax, A. and A. Michelini (2011), Tsunami early warning using earthquake rupture duration and P-wave dominant period: the importance of length and depth of faulting, Geophys. J. Int., 185, 283-291, doi: 10.1111/j.1365-246X.2010.04916.x

  5. Introducing rapid diagnostic tests for malaria into registered drug shops in Uganda: lessons learned and policy implications.

    Science.gov (United States)

    Mbonye, Anthony K; Clarke, Sîan E; Lal, Sham; Chandler, Clare I; Hutchinson, Eleanor; Hansen, Kristian S; Magnussen, Pascal

    2015-11-14

    Malaria is a major public health problem in Uganda and the current policy recommends introduction of rapid diagnostic tests for malaria (RDTs) to facilitate effective case management. However, provision of RDTs in drug shops potentially raises a new set of issues, such as adherence to RDTs results, management of severe illnesses, referral of patients, and relationship with caretakers. The main objective of the study was to examine the impact of introducing RDTs in registered drug shops in Uganda and document lessons and policy implications for future scale-up of malaria control in the private health sector. A cluster-randomized trial introducing RDTs into registered drug shops was implemented in central Uganda from October 2010 to July 2012. An evaluation was undertaken to assess the impact and the processes involved with the introduction of RDTs into drug shops, the lessons learned and policy implications. Introducing RDTs into drug shops was feasible. To scale-up this intervention however, drug shop practices need to be regulated since the registration process was not clear, supervision was inadequate and record keeping was poor. Although initially it was anticipated that introducing a new practice of record keeping would be cumbersome, but at evaluation this was not found to be a constraint. This presents an important lesson for introducing health management information system into drug shops. Involving stakeholders, especially the district health team, in the design was important for ownership and sustainability. The involvement of village health teams in community sensitization to the new malaria treatment and diagnosis policy was a success and this strategy is recommended for future interventions. Introducing RDTs into drug shops was feasible and it increased appropriate treatment of malaria with artemisinin-based combination therapy. It is anticipated that the lessons presented will help better implementation of similar interventions in the private sector.

  6. Rapid screening and identification of chemical hazards in surface and drinking water using high resolution mass spectrometry and a case-control filter.

    Science.gov (United States)

    Kaserzon, Sarit L; Heffernan, Amy L; Thompson, Kristie; Mueller, Jochen F; Gomez Ramos, Maria Jose

    2017-09-01

    Access to clean, safe drinking water poses a serious challenge to regulators, and requires analytical strategies capable of rapid screening and identification of potentially hazardous chemicals, specifically in situations when threats to water quality or security require rapid investigations and potential response. This study describes a fast and efficient chemical hazard screening strategy for characterising trace levels of polar organic contaminants in water matrices, based on liquid chromatography high resolution mass spectrometry with post-acquisition 'case-control' data processing. This method allowed for a rapid response time of less than 24 h for the screening of target, suspect and non-target unknown chemicals via direct injection analysis, and a second, more sensitive analysis option requiring sample pre-concentration. The method was validated by fortifying samples with a range of pesticides, pharmaceuticals and personal care products (n = 46); with >90% of target compounds positively screened in samples at 1 ng mL-1, and 46% at 0.1 ng mL-1 when analysed via direct injection. To simulate a contamination event samples were fortified with compounds not present in the commercial library (designated 'non-target compounds'; fipronil and fenitrothion), tentatively identified at 0.2 and 1 ng mL-1, respectively; and a compound not included in any known commercial library or public database (designated 'unknown' compounds; 8Cl- perfluorooctanesulfonic acid), at 0.8 ng mL-1. The method was applied to two 'real-case' scenarios: (1) the assessment of drinking water safety during a high-profile event in Brisbane, Australia; and (2) to screen treated, re-circulated drinking water and pre-treated (raw) water. The validated workflow was effective for rapid prioritisation and screening of suspect and non-target potential hazards at trace levels, and could be applied to a wide range of matrices and investigations where comparison of organic contaminants between

  7. Rapid word-learning in normal-hearing and hearing-impaired children: effects of age, receptive vocabulary, and high-frequency amplification.

    Science.gov (United States)

    Pittman, A L; Lewis, D E; Hoover, B M; Stelmachowicz, P G

    2005-12-01

    This study examined rapid word-learning in 5- to 14-year-old children with normal and impaired hearing. The effects of age and receptive vocabulary were examined as well as those of high-frequency amplification. Novel words were low-pass filtered at 4 kHz (typical of current amplification devices) and at 9 kHz. It was hypothesized that (1) the children with normal hearing would learn more words than the children with hearing loss, (2) word-learning would increase with age and receptive vocabulary for both groups, and (3) both groups would benefit from a broader frequency bandwidth. Sixty children with normal hearing and 37 children with moderate sensorineural hearing losses participated in this study. Each child viewed a 4-minute animated slideshow containing 8 nonsense words created using the 24 English consonant phonemes (3 consonants per word). Each word was repeated 3 times. Half of the 8 words were low-pass filtered at 4 kHz and half were filtered at 9 kHz. After viewing the story twice, each child was asked to identify the words from among pictures in the slide show. Before testing, a measure of current receptive vocabulary was obtained using the Peabody Picture Vocabulary Test (PPVT-III). The PPVT-III scores of the hearing-impaired children were consistently poorer than those of the normal-hearing children across the age range tested. A similar pattern of results was observed for word-learning in that the performance of the hearing-impaired children was significantly poorer than that of the normal-hearing children. Further analysis of the PPVT and word-learning scores suggested that although word-learning was reduced in the hearing-impaired children, their performance was consistent with their receptive vocabularies. Additionally, no correlation was found between overall performance and the age of identification, age of amplification, or years of amplification in the children with hearing loss. Results also revealed a small increase in performance for both

  8. Rapid measurement of 8-oxo-7,8-dihydro-2'-deoxyguanosine in human biological matrices using ultra-high-performance liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Lam, Patricia M W; Mistry, Vilas; Marczylo, Timothy H; Konje, Justin C; Evans, Mark D; Cooke, Marcus S

    2012-05-15

    Interaction of reactive oxygen species with DNA results in a variety of modifications, including 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG), which has been extensively studied as a biomarker of oxidative stress. Oxidative stress is implicated in a number of pathophysiological processes relevant to obstetrics and gynecology; however, there is a lack of understanding as to the precise role of oxidative stress in these processes. We aimed to develop a rapid, validated assay for the accurate quantification of 8-oxodG in human urine using solid-phase extraction and ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) and then investigate the levels of 8-oxodG in several fluids of interest to obstetrics and gynecology. Using UHPLC-MS/MS, 8-oxodG eluted after 3.94 min with an RSD for 15 injections of 0.07%. The method was linear between 0.95 and 95 nmol/L with LOD and LOQ of 5 and 25 fmol on-column, respectively. Accuracy and precision were 98.7-101.0 and seminal plasma>amniotic fluid>plasma>serum>peritoneal fluid, and it was not detected in saliva. Urine concentrations normalized to creatinine (n=15) ranged between 0.55 and 1.95 pmol/μmol creatinine. We describe, for the first time, 8-oxodG concentrations in human seminal plasma, peritoneal fluid, amniotic fluid, and breast milk, as well as in urine, plasma, and serum, using a rapid UHPLC-MS/MS method that will further facilitate biomonitoring of oxidative stress. Copyright © 2012 Elsevier Inc. All rights reserved.

  9. Identification by mass spectrometry and automated susceptibility testing from positive bottles: a simple, rapid, and standardized approach to reduce the turnaround time in the management of blood cultures.

    Science.gov (United States)

    Mauri, Carola; Principe, Luigi; Bracco, Silvia; Meroni, Elisa; Corbo, Nicoletta; Pini, Beatrice; Luzzaro, Francesco

    2017-12-06

    Speeding up identification and antimicrobial susceptibility testing (AST) is of foremost importance in the management of blood cultures. Here, we describe a simple, rapid, and standardized approach based on a very short-term incubation on solid medium from positive blood cultures followed by MALDI-TOF mass spectrometry identification and automated AST. The aim of the study was to evaluate the impact in the laboratory practice of this new procedure with respect to that previously used (standard method) by comparing TAT and cumulative percentage of final reports to clinicians. Compared with the standard method, the new procedure gave correct organism identification at genus or species level in 98.4% of monomicrobial samples. AST resulted in 97.7% essential agreement and 98.1% categorical agreement, with 0.9% minor errors, 1.0% major error, and 1.5% very major errors. The mean turnaround time to identification and AST was 61.4 h by using the new method compared to 83.1 h by using standard procedure. Concerning cumulative percentages of final reports, approximately a third of results were available at 48 h from the check-in of the sample when using the new procedure, whereas no final reports were ready at the same time with the standard method. The new procedure allows faster and reliable results using a simple and standardized approach. Thus, it represents an important tool for a more rapid management of blood cultures when molecular methods are not available in the laboratory.

  10. Validation and comparison of a rapid liquid chromatography tandem mass spectrometry method for serum 25OHD with the efficiency of separating 3-epi 25OHD3.

    Science.gov (United States)

    Yu, Songlin; Zhou, Weiyan; Zhang, Ruiping; Cheng, Xinqi; Fang, Huiling; Han, Jianhua; Cheng, Qian; Su, Wei; Qiu, Ling

    2016-09-01

    To develop a rapid liquid chromatography tandem mass spectrometry (LC-MS/MS) method with ability to separate 3-epi 25OHD3 (EPI-LC-MS/MS) from 25OHD3, and evaluate the effects of 3-epi 25OHD3 on routine LC-MS/MS that cannot separate 3-epi 25OHD3 (NEPI-LC-MS/MS). Performance of the newly built EPI-LC-MS/MS was validated, and 982 samples were analyzed and compared by the two methods. Both methods showed a linearity coefficient correlation exceeding 0.999 in the 6.25-500nmol/L range for 25OHD2 and 25OHD3. Moreover, they showed a between run coefficient variation (CV) and total CV of epi 25OHD3. Comparison of the 25OHD results obtained by the two methods for 982 patients (age 1-100years) revealed excellent clinical agreement (Cohen's kappa=0.875) and correlation (R2=0.973). Among the 982patients, only 73patients had 3-epi 25OHD3 (>6.25nmol/L); out of these 73patients, the 3-epi 25OHD3 level in 58patients was between 6.25 and 12.5nmol/L. In patients with epi 25OHD3 levels exceeding 12.5nmol/L (range: 13.3 - 27.5nmol/L). Among samples containing 3-epi 25OHD3, only three were separated into different 25OHD-deficiency groups using the above methods. A rapid and precise EPI-LC-MS/MS method for measuring 25OHD with efficient separation of 3-epi 25OHD3 was developed. Our results showed that 3-epi 25OHD3 had little effect on the routinely used NEPI-LC-MS/MS. Copyright © 2016 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

  11. Sequential determination of fat- and water-soluble vitamins in Rhodiola imbricata root from trans-Himalaya with rapid resolution liquid chromatography/tandem mass spectrometry.

    Science.gov (United States)

    Tayade, Amol B; Dhar, Priyanka; Kumar, Jatinder; Sharma, Manu; Chaurasia, Om P; Srivastava, Ravi B

    2013-07-30

    A rapid method was developed to determine both types of vitamins in Rhodiola imbricata root for the accurate quantification of free vitamin forms. Rapid resolution liquid chromatography/tandem mass spectrometry (RRLC-MS/MS) with electrospray ionization (ESI) source operating in multiple reactions monitoring (MRM) mode was optimized for the sequential analysis of nine water-soluble vitamins (B1, B2, two B3 vitamins, B5, B6, B7, B9, and B12) and six fat-soluble vitamins (A, E, D2, D3, K1, and K2). Both types of vitamins were separated by ion-suppression reversed-phase liquid chromatography with gradient elution within 30 min and detected in positive ion mode. Deviations in the intra- and inter-day precision were always below 0.6% and 0.3% for recoveries and retention time. Intra- and inter-day relative standard deviation (RSD) values of retention time for water- and fat-soluble vitamin were ranged between 0.02-0.20% and 0.01-0.15%, respectively. The mean recoveries were ranged between 88.95 and 107.07%. Sensitivity and specificity of this method allowed the limits of detection (LOD) and limits of quantitation (LOQ) of the analytes at ppb levels. The linear range was achieved for fat- and water-soluble vitamins at 100-1000 ppb and 10-100 ppb. Vitamin B-complex and vitamin E were detected as the principle vitamins in the root of this adaptogen which would be of great interest to develop novel foods from the Indian trans-Himalaya. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Matrix-assisted laser desorption/ionisation-time of flight mass spectrometry: rapid identification of bacteria isolated from patients with cystic fibrosis.

    Science.gov (United States)

    Baillie, S; Ireland, K; Warwick, S; Wareham, D; Wilks, M

    2013-01-01

    Despite extensive research into the diagnosis and management of cystic fibrosis (CF) over the past decades, sufferers still have a median life expectancy of less than 37 years. Respiratory tract infections have a significant role in increasing the morbidity and mortality of patients with CF via a progressive decline in lung function. Rapid identification of organisms recovered from CF sputum is necessary for effective management of respiratory tract infections; however, standard techniques of identification are slow, technically demanding and expensive. The aim of this study is to asses the suitability of matrix-assisted laser desorption/ionisation-time of flight mass spectrometry (MALDI-TOF MS) in identifying bacteria isolated from the respiratory tract of patients with CF, and is assessed by testing the accuracy of MALDI-TOF MS in identifying samples from a reference collection of rare CF strains in conjunction with comparing MALDI-TOF MS and standard techniques in identifying clinical isolates from sputum samples of CF patients. MALDI-TOF MS accurately identified 100% of isolates from the reference collection of rare CF pathogens (EuroCare CF collection). The isolate identification given by MALDI-TOF MS agreed with that given by standard techniques for 479/481 (99.6%) clinical isolates obtained from respiratory samples provided by patients with CE In two (0.4%) of 481 samples there was a discrepancy in identification between MALDI-TOF MS and standard techniques. One organism was identified as Pseudomonas aeruginosa by MALDI-TOF but could only be identified by the laboratory's standard methods as of the Pseudomonas genus. The second organism was identified as P. beteli by MALDI-TOF MS and Stenotrophomonas maltophilia by standard methods. This study shows that MALDI-TOF MS is superior to standard techniques in providing cheap, rapid and accurate identification of CF sputum isolates.

  13. A new approach to develop computer-aided diagnosis scheme of breast mass classification using deep learning technology.

    Science.gov (United States)

    Qiu, Yuchen; Yan, Shiju; Gundreddy, Rohith Reddy; Wang, Yunzhi; Cheng, Samuel; Liu, Hong; Zheng, Bin

    2017-01-01

    To develop and test a deep learning based computer-aided diagnosis (CAD) scheme of mammograms for classifying between malignant and benign masses. An image dataset involving 560 regions of interest (ROIs) extracted from digital mammograms was used. After down-sampling each ROI from 512×512 to 64×64 pixel size, we applied an 8 layer deep learning network that involves 3 pairs of convolution-max-pooling layers for automatic feature extraction and a multiple layer perceptron (MLP) classifier for feature categorization to process ROIs. The 3 pairs of convolution layers contain 20, 10, and 5 feature maps, respectively. Each convolution layer is connected with a max-pooling layer to improve the feature robustness. The output of the sixth layer is fully connected with a MLP classifier, which is composed of one hidden layer and one logistic regression layer. The network then generates a classification score to predict the likelihood of ROI depicting a malignant mass. A four-fold cross validation method was applied to train and test this deep learning network. The results revealed that this CAD scheme yields an area under the receiver operation characteristic curve (AUC) of 0.696±0.044, 0.802±0.037, 0.836±0.036, and 0.822±0.035 for fold 1 to 4 testing datasets, respectively. The overall AUC of the entire dataset is 0.790±0.019. This study demonstrates the feasibility of applying a deep learning based CAD scheme to classify between malignant and benign breast masses without a lesion segmentation, image feature computation and selection process.

  14. Rapid and scalable plant-based production of a cholera toxin B subunit variant to aid in mass vaccination against cholera outbreaks.

    Directory of Open Access Journals (Sweden)

    Krystal Teasley Hamorsky

    Full Text Available INTRODUCTION: Cholera toxin B subunit (CTB is a component of an internationally licensed oral cholera vaccine. The protein induces neutralizing antibodies against the holotoxin, the virulence factor responsible for severe diarrhea. A field clinical trial has suggested that the addition of CTB to killed whole-cell bacteria provides superior short-term protection to whole-cell-only vaccines; however, challenges in CTB biomanufacturing (i.e., cost and scale hamper its implementation to mass vaccination in developing countries. To provide a potential solution to this issue, we developed a rapid, robust, and scalable CTB production system in plants. METHODOLOGY/PRINCIPAL FINDINGS: In a preliminary study of expressing original CTB in transgenic Nicotiana benthamiana, the protein was N-glycosylated with plant-specific glycans. Thus, an aglycosylated CTB variant (pCTB was created and overexpressed via a plant virus vector. Upon additional transgene engineering for retention in the endoplasmic reticulum and optimization of a secretory signal, the yield of pCTB was dramatically improved, reaching >1 g per kg of fresh leaf material. The protein was efficiently purified by simple two-step chromatography. The GM1-ganglioside binding capacity and conformational stability of pCTB were virtually identical to the bacteria-derived original B subunit, as demonstrated in competitive enzyme-linked immunosorbent assay, surface plasmon resonance, and fluorescence-based thermal shift assay. Mammalian cell surface-binding was corroborated by immunofluorescence and flow cytometry. pCTB exhibited strong oral immunogenicity in mice, inducing significant levels of CTB-specific intestinal antibodies that persisted over 6 months. Moreover, these antibodies effectively neutralized the cholera holotoxin in vitro. CONCLUSIONS/SIGNIFICANCE: Taken together, these results demonstrated that pCTB has robust producibility in Nicotiana plants and retains most, if not all, of major

  15. Fully validated method for rapid and simultaneous measurement of six antiepileptic drugs in serum and plasma using ultra-performance liquid chromatography-electrospray ionization tandem mass spectrometry.

    Science.gov (United States)

    Kuhn, Joachim; Knabbe, Cornelius

    2013-06-15

    Therapeutic drug monitoring (TDM) may be very useful in the clinical management of antiepileptic drug therapy for multiple reasons, such as individual variability, metabolism, genetic factors or drug-drug or drug-food interactions. In addition, TDM is helpful to study the variation in pharmacokinetics that occurs between individuals. Here, we describe a rapid assay using ultra-performance liquid chromatography-electrospray ionization tandem mass spectrometry to measure the antiepileptic drugs lacosamide, lamotrigine, levetiracetam, primidone, topiramate, and zonisamide. After the addition of internal standards (ISs) and protein precipitation of serum or plasma, 1 μl of sample was separated on a 2.1×50 mm reverse phase column (Waters, Acquity UPLC BEH Phenyl, 1.7 μm). Analytes were then ionized and detected by electrospray ionization mass spectrometry with multiple reaction monitoring. Runtime was 2.5 min per injection. Matrix effects were investigated by systematical ion suppression and in-source fragmentation experiments. The calibration curves of the 6 antiepileptic drugs were linear over the working range between 0.05 and 50 mg/L (r>0.99). The limit of detection (LOD) was measured in the assay. The intraassay and interassay coefficients of variation for all compounds were 1.0 mg/L). Mean recoveries were between 87.8 and 98.6% for all drugs. There were no significant ion suppressions detected at the elution times of the analytes. The mean differences between serum and heparinized plasma values were less than 6% for the 6 antiepileptic drugs. All drugs were stable in serum at -20°C, 4°C, and even at RT for at least 1 month. In summary, a specific and sensitive stable isotope dilution UPLC-MS/MS method was developed and validated for routine clinical monitoring of lacosamide, lamotrigine, levetiracetam, primidone, topiramate, and zonisamide. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. Rapid simultaneous determination of paracetamol, amantadine hydrochloride, caffeine and chlorpheniramine maleate in human plasma by liquid chromatography/tandem mass spectrometry.

    Science.gov (United States)

    Feng, Shudan; Tian, Yuan; Zhang, Zunjian; Zhang, Jingjing; Huang, Meihua; Chen, Yun

    2009-01-01

    A rapid, simple and sensitive high performance liquid chromatography with positive ion electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS) was first developed and validated to simultaneously determine paracetamol (PAR, CAS 103-90-2), amantadine hydrochloride (ATH, CAS 665-66-7), caffeine (CAF, CAS 58-08-2) and chlorpheniramine maleate (CPM, CAS 113-92-8) in human plasma using tramadol hydrochloride (TMH, CAS 22204-88-2) as internal standard (IS). Following methanol-induced protein precipitation, the analytes were separated using a mobile phase comprised of methanol:water (0.5% formic acid) = 20:80 (v/v) on a commercially available column (150 mm x 2.1 mm I.D., 5 microm) and analyzed by electrospray ionization tandem mass spectrometry in the selected reaction monitoring (SRM) mode with the precursor to product ion transitions m/z 152.3-->110.2 for PAR, 152.3-->135.3 for ATH, 195.1-->138.3 for CAF, 275.2-->230.3 for CPM and 264.2-->58.2 for TMH. The standard curves were linear (r2 > 0.99) over the concentration range of 0.2-20 microg/mL for PAR, 20-2000 ng/mL for ATH and CAF, 0.1-10 ng/mL for CPM and had good accuracy and precision, respectively. The within- and between-batch precisions were less than 15% in terms of relative standard deviation (RSD). The lower limit of quantitation (LLOQ) were 0.2 microg/mL, 20 ng/mL, 20 ng/mL and 0.1 ng/mL for PAR, ATH, CAF and CPM, respectively. The described method has been successfully applied to study the pharmacokinetics of paracetamol-amantadine hydrochloride tablets in Chinese healthy male volunteers with great precision and sensitivity.

  17. Rapid determination of six carcinogenic primary aromatic amines in mainstream cigarette smoke by two-dimensional online solid phase extraction combined with liquid chromatography tandem mass spectrometry.

    Science.gov (United States)

    Bie, Zhenying; Lu, Wei; Zhu, You; Chen, Yusong; Ren, Hubo; Ji, Lishun

    2017-01-27

    A fully automated, rapid, and reliable method for simultaneous determination of six carcinogenic primary aromatic amines (AAs), including o-toluidine (o-TOL), 2, 6-dimethylaniline (2, 6-DMA), o-anisidine (o-ASD), 1-naphthylamine (1-ANP), 2-naphthylamine (2-ANP), and 4-aminobiphenyl (4-ABP), in mainstream cigarette smoke was established. The proposed method was based on two-dimensional online solid phase extraction combined with liquid chromatography tandem mass spectrometry (SPE/LC-MS/MS). The particulate phase of the mainstream cigarette smoke was collected on a Cambridge filter pad and pretreated via ultrasonic extraction with 2% formic acid (FA), while the gas phase was trapped by 2% FA without pretreatment for determination. The two-dimensional online SPE comprised of two cartridges with different absorption characteristics was applied for sample pretreatment. Analysis was performed by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) under multiple reaction monitoring mode. Each sample required about 0.5h for solid phase extraction and analysis. The limit of detections (LODs) for six AAs ranged from 0.04 to 0.58ng/cig and recoveries were within 84.5%-122.9%. The relative standard deviations of intra- and inter-day tests for 3R4F reference cigarette were less than 6% and 7%, respectively, while no more than 7% and 8% separately for a type of Virginia cigarette. The proposed method enabled minimum sample pretreatment, full automation, and high throughput with high selectivity, sensitivity, and accuracy. As a part of the validation procedure, fifteen brands of cigarettes were tested by the designed method. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Rapid determination of cocamidopropyl betaine impurities in cosmetic products by core-shell hydrophilic interaction liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Wang, Perry G; Zhou, Wanlong

    2016-08-26

    Cocamidopropyl betaine (CAPB) is a common surfactant widely used in personal care products. Dimethylaminopropylamine (DMAPA) and lauramidopropyldimethylamine (LAPDMA) are two chemicals present as impurities in CAPB and have been reported as skin sensitizers. A rapid and sensitive ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method, using a core shell hydrophilic interaction liquid chromatography (HILIC) column, has been developed to quantify DMAPA and LAPDMA in cosmetic products. Corresponding stable isotopically labeled analogues of the above native compounds were used as internal standards to compensate for matrix effect and for loss of recovery. Each sample was first screened to determine whether the sample needed to be diluted to minimize matrix effects as well as to fit the calibration range. The concept of matrix effect factor (MEF) was introduced to quantitatively evaluate each sample with a unique matrix using the internal standards. Recoveries at three spiking levels of low, medium, and high concentrations ranged from 98.4 to 112% with RSDs less than 5%. This method has been validated and is the first UHPLC-MS/MS method, which uses core shell HILIC column and stable isotopically labeled internal standards to simultaneously determine these two CAPB impurities in cosmetic products. Published by Elsevier B.V.

  19. Rapid shotgun proteomic liquid chromatography-electrospray ionization-tandem mass spectrometry-based method for the lupin ( Lupinus albus L.) multi-allergen determination in foods.

    Science.gov (United States)

    Mattarozzi, Monica; Bignardi, Chiara; Elviri, Lisa; Careri, Maria

    2012-06-13

    Allergy to lupin is a growing food safety problem because this legume, increasingly exploited in the food industry, is one of the allergens that, according to law, must be declared on the labels of food products in the European Union. In this context, a rapid targeted proteomic approach based on liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) analysis was proposed and aimed to unequivocal confirmation and reliable determination of the major lupin allergens, i.e., conglutins, in pasta and biscuits. Detected concentrations were around 1 mg of lupin/kg of pasta and biscuits, proving the capabilities of the MS-based method in terms of the sensitive allergen screening method. Good precision was observed in terms of both intra- and interday repeatability, with relative standard deviation (RSD) lower than 23%. Recoveries from 95 ± 10 to 118 ± 12% and from 103 ± 1 to 110 ± 12% ranges were calculated for biscuits and pasta, respectively. Finally, the applicability of the devised method was investigated by analyzing market samples containing lupin and samples that may possibly contain traces of lupin deriving from cross-contamination between products and production lines.

  20. Matrix-assisted laser desorption ionisation time-of-flight mass spectrometry rapid detection of carbapenamase activity in Acinetobacter baumannii isolates.

    Science.gov (United States)

    Abouseada, Noha; Raouf, May; El-Attar, Eman; Moez, Pacinte

    2017-01-01

    Carbapenamase-producing Acinetobacter baumannii are an increasing threat in hospitals and Intensive Care Units. Accurate and rapid detection of carbapenamase producers has a great impact on patient improvement and aids in implementation of infection control measures. In this study, we describe the use of matrix-assisted laser desorption ionisation time-of-flight mass spectrometry (MALDI TOF MS) to identify carbapenamase-producing A. baumannii isolates in up to 3 h. Isolates and Methods: A total of 50 A. baumannii isolates (of which 39 were carabapenamase producers) were tested using MALDI TOF MS. Isolates were incubated for 3 h with 0.25 mg/ml up to 2 mg/ml of imipenem (IMP) at 37°C. Supernatants were analysed by MALDI TOF to analyse peaks corresponding to IMP (300 Da) and an IMP metabolite (254 Da) using UltrafleXtreme (Bruker Daltonics, Bremen, Germany). All carbapenamase-producing isolates were evidenced by the disappearance or reduction in intensity of the 300 Da peak of IPM and the appearance of a 254 Da peak of the IPM metabolite. In isolates that did not produce carbapenamase, the IPM 300 Da peak remained intact. MALDI TOF is a promising tool in the field of diagnostic microbiology that has the ability to transfer identification and antimicrobial susceptibility testing time from days to hours.

  1. Soil transmitted helminths and scabies in Zanzibar, Tanzania following mass drug administration for lymphatic filariasis - a rapid assessment methodology to assess impact

    Directory of Open Access Journals (Sweden)

    Mohammed Khalfan A

    2012-12-01

    Full Text Available Abstract Background Ivermectin and albendazole are used in annual mass drug administration (MDA for the lymphatic filariasis elimination programmes in African countries co-endemic for onchocerciasis, but have additional impact on soil transmitted helminths and the ectoparasitic mite which causes scabies. Assessing these collateral impacts at scale is difficult due to the insensitivity of available parasite detection techniques. Methods The numbers of cases diagnosed with intestinal helminths and scabies and who received prescriptions for treatment were evaluated in 50 health centres in Zanzibar. Records were examined from 2000, prior to the initiation of MDA to 2005, after six rounds of MDA for lymphatic filariasis had taken place. Results Health centre records showed a consistent decline in the number of cases of intestinal helminths and scabies diagnosed by community health workers in Zanzibar and the number of prescriptions issued across five age groups. A 90-98% decline in soil transmitted helminths and 68-98% decline in scabies infections were recorded. Poisson regression models aggregated to both the island-level and district-level indicated that the decline was statistically significant. Conclusions The described method of examining health centre records has the potential for use on a large scale, despite limitations, as a rapid method to evaluate the impacts resulting from both lymphatic filariasis and onchocerciasis MDA. This would result in a reduction in the need for parasitological evaluations to determine prevalence and intensity.

  2. Validation of a rapid method of analysis using ultrahigh-performance liquid chromatography - tandem mass spectrometry for nitrogen-rich adulterants in nutritional food ingredients.

    Science.gov (United States)

    Draher, Jon; Pound, Vickie; Reddy, Todime M

    2014-12-19

    A method for the rapid quantification of 9 potential nitrogen-rich economic adulterants (dicyandiamide, urea, biuret, cyromazine, amidinourea, ammeline, amidinourea, melamine, and cyanuric acid) in five milk and soy derived nutritional ingredients, i.e. whole milk powder, nonfat dry milk, milk protein concentrate, sodium caseinate, and soy protein isolate has been developed and validated for routine use. The samples were diluted tenfold with water followed by treatment with 2% formic acid and acetonitrile to precipitate proteins. Sample extracts were analyzed using hydrophilic interaction chromatography and tandem mass spectrometry (HILIC-MS/MS) under both positive and negative modes. Stable isotope labeled internal standards were used to ensure accurate quantification. In multi-day validation experiments, the average accuracies, relative standard deviations (RSD), and method detection limits (MDL) for all analytes in whole milk powder were 82-101%, 6-13%, and 0.1mg/kg-7 mg/kg, respectively. The retention times of the analytes in matrix spiked controls were within ± 0.06 min of the average retention times of the corresponding analytes in calibration standards. The validated method was proven to be rugged for routine use to quantify the presence of 9 nitrogen-rich compounds in milk and soy derived ingredients and to provide a defense from economically motivated adulteration. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Rapid determination of pesticide residues in Chinese materia medica using QuEChERS sample preparation followed by gas chromatography–mass spectrometry

    Directory of Open Access Journals (Sweden)

    Yichen Hu

    2012-06-01

    Full Text Available Pesticide residue analysis plays an important role in the quality control of Chinese materia medica. This paper reports the development and validation of an analytical method for the quantitative determination of the residues of 39 pesticides in 12 different matrices of Chinese materia medica. Sample preparation utilized the QuEChERS method with acetonitrile:1% aqueous acetic acid (9:1, v/v as extraction solvent followed by sample clean-up by dispersive solid phase extraction using primary secondary amine sorbent and graphitized carbon black. Extracts were then analysed by gas chromatography coupled with electron impact mass spectrometry in the selected ion monitoring mode. Limit of detection (LOD and limit of quantitation (LOQ values were in the ranges 0.5–50 ng/g and 1–100 ng/g, respectively. The recoveries of the 39 pesticides were in the range 75–112% with precision (as relative standard deviation, RSD <15%. The results show that the modified QuEChERS method allows rapid and sensitive analysis of multiple pesticide residues in Chinese materia medica.

  4. Rapid gas chromatographic analysis of less abundant compounds in distilled spirits by direct injection with ethanol-water venting and mass spectrometric data deconvolution.

    Science.gov (United States)

    Macnamara, Kevin; Lee, Michelle; Robbat, Albert

    2010-01-01

    The principal trace secondary compounds common to fermentation-derived distilled spirits can be rapidly quantified by directly injecting 5muL of spirit without sample preparation to a narrow-bore 0.15mm internal diameter capillary column. The ethanol-water is removed in an initial solvent venting step using a programmed temperature vapourization injector, followed by splitless transfer of the target analytes to the column. The larger injection facilitates trace analysis and ethanol-water removal extends column lifetime. Problems of coelution between analytes or with sample matrix were surmounted by using mass spectral deconvolution software for quantification. All operations in the analysis from injection with solvent venting to data reduction are fully automated for unattended sequential sample analysis. The synergy of the various contributory steps combines to offer an effective novel solution for this analysis. Applications include quantification of low ppm amounts of acids and esters and sub-ppm profiling of trace compounds from both the raw material malt and the ageing in wood barrels. Copyright 2009 Elsevier B.V. All rights reserved.

  5. Direct analysis in real time-mass spectrometry (DART-MS) for rapid qualitative screening of toxic glycols in glycerin-containing products.

    Science.gov (United States)

    Self, Randy L

    2013-06-01

    In 2007, the United States Food and Drug Administration released guidance recommending testing of glycerin used in regulated consumer products, such as cough syrup preparations, toothpaste, and other pharmaceutical and food products, for the toxic compounds ethylene glycol and diethylene glycol. Regulatory laboratories routinely test glycerin, and products containing glycerin or related compounds for these toxic glycols, using an official gas chromatographic method, to ensure the safety of these products. The current work describes a companion technique to compliment this GC-FID method utilizing Orbitrap mass spectrometry with direct analysis in real time ionization to rapidly screen these samples qualitatively, with results in as little as five seconds, with no sample preparation required. This allows the more time and resource intensive method to be reserved for those rare cases when these compounds are detected, potentially greatly improving laboratory efficiency. The technique was evaluated for qualitative sensitivity and repeatability, and compared against the GC-FID method. The method appears to perform well against these metrics. Published by Elsevier B.V.

  6. Rapid determination of endogenous cytokinins in plant samples by combination of magnetic solid phase extraction with hydrophilic interaction chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Liu, Zhao; Cai, Bao-Dong; Feng, Yu-Qi

    2012-04-01

    A 2-acrylamido-2-methyl-1-propanesulfonic acid-co-ethylene glycol dimethacrylate (Fe₃O₄/SiO₂/P(AMPS-co-EGDMA)) copolymer was prepared and used as a magnetic solid phase extraction (MSPE) medium for recovery of endogenous cytokinins (CKs) from plant extracts. This magnetic porous polymer was characterized by electron microscopy, nitrogen sorption experiments, elemental analysis and Fourier-transformed infrared spectroscopy. It was demonstrated to have high extraction capacity toward CKs in plants due to its specificity, surface area and porous structure. Coupled with hydrophilic interaction chromatography-tandem mass spectrometry (HILIC-MS/MS), a rapid, simple, and effective MSPE-HILIC-MS/MS analytical method for the quantitative analysis of endogenous CKs in Oryza sativa (O. sativa) roots was successfully established. Good linearities were obtained for all CKs investigated with correlation coefficients (R²>0.9975. The results showed that LODs (S/N=3) were ranged from 0.18 to 3.65 pg mL⁻¹. Reproducibility of the method was obtained with intra-day and inter-day relative standard deviations (RSDs) less than 16.1% and the recoveries in plant samples ranged from 72.8% to 115.5%. Finally, the MSPE-HILIC-MS/MS method was applied to several plant samples, and the amounts of endogenous CKs in O. sativa roots, leaves and Arabidopsis thaliana (A. thaliana) were successfully determined. Copyright © 2012 Elsevier B.V. All rights reserved.

  7. A new membrane inlet interface of a vacuum ultraviolet lamp ionization miniature mass spectrometer for on-line rapid measurement of volatile organic compounds in air.

    Science.gov (United States)

    Hou, Keyong; Wang, Junde; Li, Haiyang

    2007-01-01

    A novel membrane inlet interface coupled to a single-photon ionization (SPI) miniature time-of-flight mass spectrometer has been developed for on-line rapid measurement of volatile organic compounds (VOCs). The vacuum ultraviolet (VUV) light source for SPI was a commercial krypton discharge lamp with photon energy of 10.6 eV and photon flux of 10(10) photons/s. The experimental results showed that the sensitivity was 5 times as high as obtained with the traditional membrane inlet. The enrichment efficiency could be adjusted in the range of 10 to 20 times for different VOCs when a buffer cell was added to the inlet interface, and the memory effect was effectively eliminated. A detection limit as low as 25 parts-per-billion by volume (ppbv) for benzene has been achieved, with a linear dynamic range of three orders of magnitude. The rise times were 6 s, 10 s and 15 s for benzene, toluene and p-xylene, respectively, and the fall time was only 6 s for all of these compounds. The analytical capacity of this system was demonstrated by the on-line analysis of VOCs in single puff mainstream cigarette smoke, in which more than 50 compounds were detected in 2 s. Copyright 2007 John Wiley & Sons, Ltd.

  8. Rapid determination of caffeine in one drop of beverages and foods using drop-to-drop solvent microextraction with gas chromatography/mass spectrometry.

    Science.gov (United States)

    Shrivas, Kamlesh; Wu, Hui-Fen

    2007-11-02

    A simple and rapid sample cleanup and preconcentration method for the quantitative determination of caffeine in one drop of beverages and foods by gas chromatography/mass spectrometry (GC/MS) has been proposed using drop-to-drop solvent microextraction (DDSME). The best optimum experimental conditions for DDSME were: chloroform as the extraction solvent, 5 min extraction time, 0.5 microL exposure volume of the extraction phase and no salt addition at room temperature. The optimized methodology exhibited good linearity between 0.05 and 5.0 microg/mL with correlation coefficient of 0.980. The relative standard deviation (RSD) and limits of detection (LOD) of the DDSME/GC/MS method were 4.4% and 4.0 ng/mL, respectively. Relative recovery of caffeine in beverages and foods were found to be 96.6-101%, which showing good reliability of this method. This DDSME excludes the major disadvantages of conventional method of caffeine extraction, like large amount of organic solvent and sample consumption and long sample pre-treatment process. So, this approach proves that the DDSME/GC/MS technique can be applied as a simple, fast and feasible diagnosis tool for environmental, food and biological application for extremely small amount of real sample analysis.

  9. Integration of Affinity Selection-Mass Spectrometry and Functional Cell-Based Assays to Rapidly Triage Druggable Target Space within the NF-κB Pathway.

    Science.gov (United States)

    Kutilek, Victoria D; Andrews, Christine L; Richards, Matthew P; Xu, Zangwei; Sun, Tianxiao; Chen, Yiping; Hashke, Andrew; Smotrov, Nadya; Fernandez, Rafael; Nickbarg, Elliott B; Chamberlin, Chad; Sauvagnat, Berengere; Curran, Patrick J; Boinay, Ryan; Saradjian, Peter; Allen, Samantha J; Byrne, Noel; Elsen, Nathaniel L; Ford, Rachael E; Hall, Dawn L; Kornienko, Maria; Rickert, Keith W; Sharma, Sujata; Shipman, Jennifer M; Lumb, Kevin J; Coleman, Kevin; Dandliker, Peter J; Kariv, Ilona; Beutel, Bruce

    2016-07-01

    The primary objective of early drug discovery is to associate druggable target space with a desired phenotype. The inability to efficiently associate these often leads to failure early in the drug discovery process. In this proof-of-concept study, the most tractable starting points for drug discovery within the NF-κB pathway model system were identified by integrating affinity selection-mass spectrometry (AS-MS) with functional cellular assays. The AS-MS platform Automated Ligand Identification System (ALIS) was used to rapidly screen 15 NF-κB proteins in parallel against large-compound libraries. ALIS identified 382 target-selective compounds binding to 14 of the 15 proteins. Without any chemical optimization, 22 of the 382 target-selective compounds exhibited a cellular phenotype consistent with the respective target associated in ALIS. Further studies on structurally related compounds distinguished two chemical series that exhibited a preliminary structure-activity relationship and confirmed target-driven cellular activity to NF-κB1/p105 and TRAF5, respectively. These two series represent new drug discovery opportunities for chemical optimization. The results described herein demonstrate the power of combining ALIS with cell functional assays in a high-throughput, target-based approach to determine the most tractable drug discovery opportunities within a pathway. © 2016 Society for Laboratory Automation and Screening.

  10. Rapid and selective determination of free chlorine in aqueous solution using electrophilic addition to styrene by gas chromatography/mass spectrometry.

    Science.gov (United States)

    Wakigawa, Kengo; Gohda, Akinaga; Fukushima, Sunao; Mori, Takeshi; Niidome, Takuro; Katayama, Yoshiki

    2013-01-15

    We developed a rapid and selective method for determination of free chlorine in aqueous solution by gas chromatography/mass spectrometry for the first time. Free chlorine was converted to styrene chlorohydrin using electrophilic addition to styrene in sodium acetate buffer solution (pH 5). The chlorine derivative obtained was extracted with chloroform, and then analyzed by GC/MS. The calibration curve showed good linearity from 0.2-100 μg/mL (as available chlorine). The detection limit was 0.1 μg/mL, and the intra- and interday accuracy were measured at concentrations of 10, 50, and 75 μg/mL to be -1.3 to 6.9% (intraday) and 3.8-8.0% (interday) as % Bias. The precision was between 1.4 and 4.5% as % RSD. These results indicate that this method is a superior technique for the identification of free chlorine. This method was successfully applied to quantification in commercial samples and in samples of a criminal case. Copyright © 2012 Elsevier B.V. All rights reserved.

  11. A rapid gas chromatographic injection-port derivatization method for the tandem mass spectrometric determination of patulin and 5-hydroxymethylfurfural in fruit juices.

    Science.gov (United States)

    Marsol-Vall, Alexis; Balcells, Mercè; Eras, Jordi; Canela-Garayoa, Ramon

    2016-07-01

    A novel method consisting of injection-port derivatization coupled to gas chromatography-tandem mass spectrometry is described. The method allows the rapid assessment of 5-hydroxymethylfurfural (HMF) and patulin content in apple and pear derivatives. The chromatographic separation of the compounds was achieved in a short chromatographic run (12.2min) suitable for routine controls of these compounds in the fruit juice industry. The optimal conditions for the injection-port derivatization were at 270°C, 0.5min purge-off, and a 1:2 sample:derivatization reagent ratio (v/v). These conditions represent an important saving in terms of derivatization reagent consumption and sample preparation time. Quality parameters were assessed for the target compounds, giving LOD of 0.7 and 1.6μg/kg and LOQ of 2 and 5μg/kg for patulin and HMF, respectively. These values are below the maximum patulin concentration in food products intended for infants and young children. Repeatability (%RSD n=5) was below 12% for both compounds. In addition, the method linearity ranged between 25 and 1000μg/kg and between 5 and 192μg/kg for HMF and patulin, respectively. Finally, the method was applied to study HMF and patulin content in various fruit juice samples. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Capillary electrophoresis coupled with inductively coupled mass spectrometry as an alternative to cloud point extraction based methods for rapid quantification of silver ions and surface coated silver nanoparticles.

    Science.gov (United States)

    Qu, Haiou; Mudalige, Thilak K; Linder, Sean W

    2016-01-15

    Speciation and accurate quantification of ionic silver and metallic silver nanoparticles are critical to investigate silver toxicity and to determine the shelf-life of products that contain nano silver under various storage conditions. We developed a rapid method for quantification of silver ions and silver nanoparticles using capillary electrophoresis (CE) interfaced with inductively-coupled plasma mass spectrometry (ICPMS). The addition of 2-mercaptopropionylglycine (tiopronin) to the background electrolyte was used to facilitate the chromatographic separation of ionic silver and maintain the oxidation state of silver. The obtained limits of detection were 0.05 μg kg(-1) of silver nanoparticles and 0.03 μg kg(-1) of ionic silver. Nanoparticles of varied sizes (10-110 nm) with different surface coating, including citrate acid, lipoic acid, polyvinylpyrrolidone and bovine serum albumin (BSA) were successfully analyzed. Particularly good recoveries (>93%) were obtained for both ionic silver and silver nanoparticle in the presence of excess amount of BSA. The method was further tested with six commercially available dietary supplements which varied in concentration and matrix components. The summed values of silver ions and silver nanoparticles correlated well with the total silver concentration determined by ICPMS after acid digestion. This method can serve as an alternative to cloud point extraction technique when the extraction efficiency for protein coated nanoparticles is low. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Rapid identification viruses from nasal pharyngeal aspirates in acute viral respiratory infections by RT-PCR and electrospray ionization mass spectrometry.

    Science.gov (United States)

    Chen, Kuan-Fu; Rothman, Richard E; Ramachandran, Padmini; Blyn, Lawrence; Sampath, Rangarajan; Ecker, David J; Valsamakis, Alexandra; Gaydos, Charlotte A

    2011-04-01

    Diagnosis of the etiologic agent of respiratory viral infection relies traditionally on culture or antigen detection. This pilot evaluation compared performance characteristics of the RT-PCR and electrospray ionization mass spectrometry (RT-PCR/ESI-MS) platform to conventional virologic methods for identifying multiple clinically relevant respiratory viruses in nasopharyngeal aspirates. The RT-PCR/ESI-MS respiratory virus surveillance kit was designed to detect respiratory syncytial virus, influenza A and B, parainfluenza types 1-4, adenoviridae types A-F, coronaviridae, human bocavirus, and human metapneumovirus. Patients (N=192) attending an emergency department during the 2007-2008 respiratory season consented, and "excess" frozen archived nasopharyngeal aspirates were analysed; 46 were positive by conventional virology and 69 by RT-PCR/ESI-MS, among which there were six samples with multiple viral pathogens detected. The sensitivity and specificity of the assay were 89.1% and 80.3%, respectively. Additional viruses that were not identified by conventional virology assays were detected (4 human bocaviruses and 7 coronaviruses). Samples in which the RT-PCR/ESI-MS results disagreed with conventional virology were sent for analysis by a third method using a commercial RT-PCR-based assay, which can identify viruses not detectable by conventional virologic procedures. Time to first result of RT-PCR/ESI-MS was 8h. RT-PCR/ESI-MS demonstrated capacity to detect respiratory viruses identifiable and unidentifiable by conventional methods rapidly. Copyright © 2011 Elsevier B.V. All rights reserved.

  14. A simple and rapid ultra-high-performance liquid chromatography-tandem mass spectrometry method to determine plasma biotin in hemodialysis patients.

    Science.gov (United States)

    Yagi, Shigeaki; Nishizawa, Manabu; Ando, Itiro; Oguma, Shiro; Sato, Emiko; Imai, Yutaka; Fujiwara, Masako

    2016-08-01

    A simple, rapid, and selective method for determination of plasma biotin was developed using ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). After single-step protein precipitation with methanol, biotin and stable isotope-labeled biotin as an internal standard (IS) were chromatographed on a pentafluorophenyl stationary-phase column (2.1 × 100 mm, 2.7 μm) under isocratic conditions using 10 mm ammonium formate-acetonitrile (93:7, v/v) at a flow rate of 0.6 mL/min. The total chromatographic runtime was 5 min for each injection. Detection was performed in a positive electrospray ionization mode by monitoring selected ion transitions at m/z 245.1/227.0 and 249.1/231.0 for biotin and the IS, respectively. The calibration curve was linear in the range of 0.05-2 ng/mL using 300 μL of plasma. The intra- and inter-day precisions were all biotin concentrations in hemodialysis patients. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  15. Rapid determination of acetone in human blood by derivatization with pentafluorobenzyl hydroxylamine followed by headspace liquid-phase microextraction and gas chromatography/mass spectrometry.

    Science.gov (United States)

    Deng, Chunhui; Li, Ning; Wang, Xiaochuan; Zhang, Xiangmin; Zeng, Jia

    2005-01-01

    In the current work, a simple, rapid, accurate and inexpensive method was developed for the determination of acetone in human blood. The proposed method is based on derivatization with O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine hydrochloride (PFBHA), followed by headspace liquid-phase microextraction (HS-LPME) and gas chromatography/mass spectrometry (GC/MS). In the present method, acetone in blood samples was derivatized with PFBHA and acetone oxime formed in several seconds. The formed oxime was enriched by HS-LPME using the organic solvent film (OSF) formed in a microsyringe barrel as extraction interface. Finally, the enriched oxime was analyzed by GC/MS in electron ionization (EI) mode. HS-LPME parameters including solvent, syringe plunger withdrawal rate, sampling volume, and extraction cycle were optimized and the method reproducibility, linearity, recovery and detection limit were studied. The proposed method was applied to determination of acetone in diabetes blood and normal blood. It has been shown that derivatization with HS-LPME and GC/MS is an alternative method for determination of the diabetes biomarker, acetone, in blood samples.

  16. Rapid and precise measurement of serum branched-chain and aromatic amino acids by isotope dilution liquid chromatography tandem mass spectrometry.

    Directory of Open Access Journals (Sweden)

    Ruiyue Yang

    Full Text Available BACKGROUND: Serum branched-chain and aromatic amino acids (BCAAs and AAAs have emerged as predictors for the future development of diabetes and may aid in diabetes risk assessment. However, the current methods for the analysis of such amino acids in biological samples are time consuming. METHODS: An isotope dilution liquid chromatography tandem mass spectrometry (ID-LC/MS/MS method for serum BCAAs and AAAs was developed. The serum was mixed with isotope-labeled BCAA and AAA internal standards and the amino acids were extracted with acetonitrile, followed by analysis using LC/MS/MS. The LC separation was performed on a reversed-phase C18 column, and the MS/MS detection was performed via the positive electronic spray ionization in multiple reaction monitoring mode. RESULTS: Specific analysis of the amino acids was achieved within 2 min. Intra-run and total CVs for the amino acids were less than 2% and 4%, respectively, and the analytical recoveries ranged from 99.6 to 103.6%. CONCLUSION: A rapid and precise method for the measurement of serum BCAAs and AAAs was developed and may serve as a quick tool for screening serum BCAAs and AAAs in studies assessing diabetes risk.

  17. Activation of phasic pontine-wave generator prevents rapid eye movement sleep deprivation-induced learning impairment in the rat: a mechanism for sleep-dependent plasticity.

    Science.gov (United States)

    Datta, Subimal; Mavanji, Vijayakumar; Ulloor, Jagadish; Patterson, Elissa H

    2004-02-11

    Animal and human studies of sleep and learning have demonstrated that training on various tasks increases subsequent rapid eye movement (REM) sleep and phasic pontine-wave (P-wave) activity, followed by improvement in performance on the learned task. It is well documented that REM sleep deprivation after learning trials blocks the expected improvement in performance on subsequent retesting. Our aim was to test whether experimentally induced P-wave generator activation could eliminate the learning impairment produced by post-training REM sleep deprivation. Rats were trained on a two-way active avoidance-learning task. Immediately thereafter, two groups of those rats received a control vehicle (100 nl saline) microinjection and one group received a carbachol (50 ng in 100 nl saline) microinjection into the P-wave generator. The carbachol-injected group and one of the two control saline microinjected groups were selectively deprived of REM sleep during a 6 hr polygraphic recording session. All rats were then tested on the avoidance-learning task. The rats that received both the control saline injection and REM sleep deprivation showed learning deficits compared with the control saline-injected rats that were allowed to sleep normally. In contrast, the rats that received the carbachol microinjection and REM sleep deprivation demonstrated normal learning. These results demonstrate, for the first time, that carbachol-induced activation of the P-wave generator prevents the memory-impairing effects of post-training REM sleep deprivation. This evidence supports our hypothesis that the activation of the P-wave generator during REM sleep deprivation enhances a physiological process of memory, which occurs naturally during post-training REM sleep.

  18. Acute incident rapid response at a mass-gathering event through comprehensive planning systems: a case report from the 2013 Shamrock Shuffle.

    Science.gov (United States)

    Başdere, Mehmet; Ross, Colleen; Chan, Jennifer L; Mehrotra, Sanjay; Smilowitz, Karen; Chiampas, George

    2014-06-01

    Planning and execution of mass-gathering events involves various challenges. In this case report, the Chicago Model (CM), which was designed to organize and operate such events and to maintain the health and wellbeing of both runners and the public in a more effective way, is described. The Chicago Model also was designed to prepare for unexpected incidents, including disasters, during the marathon event. The model has been used successfully in the planning and execution stages of the Bank of America Shamrock Shuffle and the Bank of America Chicago Marathon since 2008. The key components of the CM are organizational structure, information systems, and communication. This case report describes how the organizers at the 2013 Shamrock Shuffle used the key components of the CM approach in order to respond to an acute incident caused by a man who was threatening to jump off the State Street Bridge. The course route was changed to accommodate this unexpected event, while maintaining access to key health care facilities. The lessons learned from the incident are presented and further improvements to the existing model are proposed.

  19. Rapid and reliable species identification of wild mushrooms by matrix assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS).

    Science.gov (United States)

    Sugawara, Ryota; Yamada, Sayumi; Tu, Zhihao; Sugawara, Akiko; Suzuki, Kousuke; Hoshiba, Toshihiro; Eisaka, Sadao; Yamaguchi, Akihiro

    2016-08-31

    Mushrooms are a favourite natural food in many countries. However, some wild species cause food poisoning, sometimes lethal, due to misidentification caused by confusing fruiting bodies similar to those of edible species. The morphological inspection of mycelia, spores and fruiting bodies have been traditionally used for the identification of mushrooms. More recently, DNA sequencing analysis has been successfully applied to mushrooms and to many other species. This study focuses on a simpler and more rapid methodology for the identification of wild mushrooms via protein profiling based on matrix-assisted laser desorption/ionization mass spectrometry (MALDI-TOF MS). A preliminary study using 6 commercially available cultivated mushrooms suggested that a more reproducible spectrum was obtained from a portion of the cap than from the stem of a fruiting body by the extraction of proteins with a formic acid-acetonitrile mixture (1 + 1). We used 157 wild mushroom-fruiting bodies collected in the centre of Hokkaido from June to November 2014. Sequencing analysis of a portion of the ribosomal RNA gene provided 134 identifications of mushrooms by genus or species, however 23 samples containing 10 unknown species that had lower concordance rate of the nucleotide sequences in a BLAST search (less than 97%) and 13 samples that had unidentifiable poor or mixed sequencing signals remained unknown. MALDI-TOF MS analysis yielded a reproducible spectrum (frequency of matching score ≥ 2.0 was ≥6 spectra from 12 spectra measurements) for 114 of 157 samples. Profiling scores that matched each other within the database gave correct species identification (with scores of ≥2.0) for 110 samples (96%). An in-house prepared database was constructed from 106 independent species, except for overlapping identifications. We used 48 wild mushrooms that were collected in autumn 2015 to validate the in-house database. As a result, 21 mushrooms were identified at the species level with

  20. A temperature programmed reaction/single-photon ionization time-of-flight mass spectrometry system for rapid investigation of gas-solid heterogeneous catalytic reactions under realistic reaction conditions

    NARCIS (Netherlands)

    He, Songbo; Cui, Huapeng; Lai, Yulong; Sun, Chenglin; Luo, Sha; Li, Haiyang; Seshan, Kulathuiyer

    2015-01-01

    A Temperature-Programmed Reaction (TPRn)/Single-Photon Ionization Time-of-Flight Mass Spectrometry (SPI-TOF-MS) system is described. The TPRn/SPI-TOF-MS system allows rapid characterization of heterogeneous catalytic reactions under realistic reaction conditions and at the same time allows for the

  1. On-line solid-phase extraction-short-column liquid chromatography combined with various tandem mass spectrometric scanning strategies for the rapid study of transformation of pesticides in surface water.

    NARCIS (Netherlands)

    Hogenboom, A.C.; Niessen, W.M.A.; Brinkman, U.A.T.

    1999-01-01

    The applicability of solid-phase extraction-short-column liquid chromatography using two short columns (i.e., 10 and 20 mm long) coupled on-line with tandem mass spectrometric detection is demonstrated for the rapid degradation study of pesticides and their transformation products in water at the

  2. Rapid identification and quantification of methamphetamine and amphetamine in hair by gas chromatography/mass spectrometry coupled with micropulverized extraction, aqueous acetylation and microextraction by packed sorbent.

    Science.gov (United States)

    Miyaguchi, Hajime; Iwata, Yuko T; Kanamori, Tatsuyuki; Tsujikawa, Kenji; Kuwayama, Kenji; Inoue, Hiroyuki

    2009-05-01

    We developed a rapid identification and quantification method for the toxicological analysis of methamphetamine and amphetamine in human hair by gas chromatography/mass spectrometry coupled with a novel combination of micropulverized extraction, aqueous acetylation and microextraction by packed sorbent (MEPS) named MiAMi-GC/MS. A washed hair sample (1-5 mg) was micropulverized for 5 min in a 2 mL plastic tube with 250 microL of water. An anion-exchange sorbent was added to adsorb anionic interferences. After removing the residue with a membrane-filter unit, sodium carbonate and acetic anhydride was admixed in turn. Acetylation was completed in approximately 20 min at room temperature. The acetylated analytes in the reaction liquid were concentrated to an octadecylsilica sorbent packed in the needle of a syringe by a CombiPAL autosampler. Elution was carried out with 50 microL of methanol, and the entire eluate injected into a gas chromatograph using a programmable temperature vaporizing (PTV) technique. The time required for sample preparation and GC/MS analysis was approximately 1 h from a washed hair sample, and an evaporation process was not required. Ranges for quantification were 0.20-50 (ng/mg) each for methamphetamine and amphetamine using 1 mg of hair. Accuracy and relative standard deviation (RSD) were evaluated intraday and interday at three concentrations, and the results were within the limit of a guidance issued by U.S. Food and Drug Administration. For identification, full-scan mass spectra of methamphetamine and amphetamine were obtained using 5 mg of fortified hair samples at 0.2 ng/mg. The extraction device of MEPS was durable for at least 300 extractions, whereas the liner of the gas chromatograph should be replaced after 20-30 times use. The carry over was estimated to be about 1-2%. This sample-preparation method coupled with GC/MS is fast and labor-saving in comparison with conventional methods.

  3. Rapid whole monoclonal antibody analysis by mass spectrometry: An ultra scale-down study of the effect of harvesting by centrifugation on the post-translational modification profile.

    Science.gov (United States)

    Reid, C Q; Tait, A; Baldascini, H; Mohindra, A; Racher, A; Bilsborough, S; Smales, C M; Hoare, M

    2010-09-01

    With the trend towards the generation and production of increasing numbers of complex biopharmaceutical (protein based) products, there is an increased need and requirement to characterize both the product and production process in terms of robustness and reproducibility. This is of particular importance for products from mammalian cell culture which have large molecular structures and more often than not complex post-translational modifications (PTMs) that can impact the efficacy, stability and ultimately the safety of the final product. It is therefore vital to understand how the operating conditions of a bioprocess affect the distribution and make up of these PTMs to ensure a consistent quality and activity in the final product. Here we have characterized a typical bioprocess and determined (a) how the time of harvest from a mammalian cell culture and, (b) through the use of an ultra scale-down mimic how the nature of the primary recovery stages, affect the distribution and make up of the PTMs observed on a recombinant IgG(4) monoclonal antibody. In particular we describe the use of rapid whole antibody analysis by mass spectrometry to analyze simultaneously the changes that occur to the cleavage of heavy chain C-terminal lysine residues and the glycosylation pattern, as well as the presence of HL dimers. The time of harvest was found to have a large impact upon the range of glycosylation patterns observed, but not upon C-terminal lysine cleavage. The culture age had a profound impact on the ratio of different glycan moieties found on antibody molecules. The proportion of short glycans increased (e.g., (G0F)(2) 20-35%), with an associated decrease in the proportion of long glycans with culture age (e.g., (G2F)(2) 7-4%, and G1F/G2F from 15.2% to 7.8%). Ultra scale-down mimics showed that subsequent processing of these cultures did not change the post-translational modifications investigated, but did increase the proportion of half antibodies present in the

  4. Development of a rapid method for the analysis of synthetic growth promoters in bovine muscle using liquid chromatography tandem mass spectrometry.

    Science.gov (United States)

    Malone, E M; Elliott, C T; Kennedy, D G; Regan, L

    2009-04-01

    A rapid liquid chromatography tandem mass spectrometry (LC-MS/MS) method has been developed and validated for the simultaneous identification, confirmation and quantitation of thirteen synthetic growth promoters in bovine muscle. The method was validated in accordance with the criteria defined in Commission Decision 2002/657/EC. A value of 1mugkg(-1) was chosen as the required performance level (RPL) for all analytes. The growth promoters investigated were alpha and beta trenbolone, 16-beta-OH stanozolol, methylboldenone, fluoxymesterone, methyltestosterone, medroxyprogesterone acetate, megestrol acetate, melengestrol acetate, dexamethasone, flumethasone, dienestrol and hexestrol. The method involved enzymatic hydrolysis, purification by solid phase extraction followed by analysis by UPLC-MS/MS using electrospray ionization operated in both positive and negative polarities with a total run time of 14 min. The decision limit (CCalpha) values obtained, ranged from 0.09 to 0.19 microgkg(-1) and the detection capability (CCbeta) values obtained, ranged from 0.15 to 0.32 microgkg(-1). The results of the inter-assay study, which was performed by fortifying bovine muscle samples (n=18) on three separate days, show the accuracy calculated for the various analytes to range between 98% and 102%. The precision of the method, expressed as R.S.D. values for the inter-assay variation of each analyte at the three levels of fortification (1, 1.5 and 2.0 microgkg(-1)), ranged between 3.1% and 5.8%. A Day 4 assay was carried out to examine variations due to different animals and different muscle types.

  5. Matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS) for rapid identification of micro-organisms in the routine clinical microbiology laboratory.

    Science.gov (United States)

    Wattal, C; Oberoi, J K; Goel, N; Raveendran, R; Khanna, S

    2017-05-01

    The study evaluates the utility of matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS) Vitek MS for identification of microorganisms in the routine clinical microbiology laboratory. From May 2013 to April 2014, microbial isolates recovered from various clinical samples were identified by Vitek MS. In case of failure to identify by Vitek MS, the isolate was identified using the Vitek 2 system (bioMerieux, France) and serotyping wherever applicable or otherwise by nucleic acid-mediated methods. All the moulds were identified by Lactophenol blue mounts, and mycobacterial isolates were identified by molecular identification systems including AccuProbe (bioMerieux, France) or GenoType Mycobacterium CM (Hain Lifescience, Germany). Out of the 12,003 isolates, the Vitek MS gave a good overall ID at the genus and or species level up to 97.7% for bacterial isolates, 92.8% for yeasts and 80% for filamentous fungi. Of the 26 mycobacteria tested, only 42.3% could be identified using the Saramis RUO (Research Use Only) database. VITEK MS could not identify 34 of the 35 yeast isolates identified as C. haemulonii by Vitek 2. Subsequently, 17 of these isolates were identified as Candida auris (not present in the Vitek MS database) by 18S rRNA sequencing. Using these strains, an in-house superspectrum of C. auris was created in the VITEK MS database. Use of MALDI-TOF MS allows a rapid identification of aerobic bacteria and yeasts in clinical practice. However, improved sample extraction protocols and database upgrades with inclusion of locally representative strains is required, especially for moulds.

  6. Rapid and simple analysis of disease-associated biomarkers of Taiwanese patients with schizophrenia using matrix-assisted laser desorption ionization mass spectrometry.

    Science.gov (United States)

    Huang, Tiao-Lai; Lo, Li-Hua; Shiea, Jentaie; Su, Hung

    2017-10-01

    Matrix-assisted laser desorption ionization/time-of-flight mass spectrometry (MALDI-TOF MS) is an extremely sensitive analytical tool for characterizing biological compounds in bio samples. In this study, we applied MALDI-TOF MS to assess potential protein biomarkers in the peripheral blood mononuclear cells (PBMCs) of patients with schizophrenia in the acute phase, recovery phase and healthy controls in Taiwan. We recruited 40 participants, including 20 pairs of patients diagnosed with schizophrenia in the acute phase, after four-week treatment with drug in the recovery phase, and 20 healthy controls. The schizophrenic patients were diagnosed using Structured Clinical Interview for DSM-IV Axis I Disorders (SCID), and severity was assessed by a positive and negative symptom scale at baseline and at endpoint following four-week treatment with drug. The patients' PBMCs biomarkers were rapidly measured using a technique that combines MALDI-TOF MS and principle component analysis. A receiver operating characteristic curve was created for the evaluated biomarker. Significant differences in α-defensins 1-3 were found between the patients in acute phase with schizophrenia and the healthy controls, but not between the schizophrenic patients in recovery phase and healthy controls or between the schizophrenic patients in acute phase and in recovery phase. α-Defensins can be biomarkers of Taiwanese patients with schizophrenia, thus supporting the hypothesis that the inflammatory response and immunity system is correlated with the pathophysiology of schizophrenia. Moreover, the result also implies that α-defensins may be related in schizophrenia-associated disease not in efficacy of drug-treatment. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Rapid and sensitive serum glucose determination using chemical labeling coupled with black phosphorus-assisted laser desorption/ionization time-of-flight mass spectrometry.

    Science.gov (United States)

    Wang, Qing; Yu, Lei; Qi, Chu-Bo; Ding, Jun; He, Xiao-Mei; Wang, Ren-Qi; Feng, Yu-Qi

    2018-01-01

    Monitoring the concentration of blood glucose in patients is a key component of good medical diagnoses. Therefore, developing an accurate, rapid and sensitive strategy for monitoring blood glucose is of vital importance. We proposed a strategy for serum glucose determination combining 2-(4-boronobenzyl) isoquinolin-2-ium bromide chemical labeling with black phosphorus assisted laser desorption ionization-time of flight mass spectrometry (CL-BP/ALDI-TOF MS). The entire analytical process consisted of 1min of protein precipitation and 3min of chemical labeling in a microwave oven prior to the BP/ALDI-TOF MS analysis. The analysis can be completed in 5min with high throughput and extremely low sample consumption. Good linearity for glucose was obtained with a correlation coefficient (R) of 0.9986. The limit of detection (LOD) and limit of quantification (LOQ) were 11.5 fmol and 37.5 fmol, respectively. Satisfied reproducibility and reliability were gained by evaluation of the intra- and inter-day precisions with relative standard deviations (RSDs) less than 7.2% and relative recoveries ranging from 87.1% to 108.1%, respectively. The proposed strategy was also applied for the analysis of endogenous glucose in various serum samples and the results were consistent with those obtained using the hexokinase method in a clinical laboratory. Considering the results, the proposed CL-BP/ALDI-TOF MS strategy has proven to be reliable, fast, and sensitive for quantitative analysis of serum glucose. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Rapid enrichment of (homo)acetogenic consortia from animal feces using a high mass-transfer gas-lift reactor fed with syngas.

    Science.gov (United States)

    Park, Shinyoung; Yasin, Muhammad; Kim, Daehee; Park, Hee-Deung; Kang, Chang Min; Kim, Duk Jin; Chang, In Seop

    2013-09-01

    A gas-lift reactor having a high mass transfer coefficient (k(L)a = 80.28 h(-1)) for a relatively insoluble gas (carbon monoxide; CO) was used to enrich (homo)acetogens from animal feces. Samples of fecal matter from cow, rabbit, chicken, and goat were used as sources of inoculum for the enrichment of CO and H(2) utilizing microbial consortia. To confirm the successful enrichment, the Hungate roll tube technique was employed to count and then isolate putative CO utilizers. The results of this work showed that CO and H(2) utilizing consortia were established for each inoculum source after 8 days. The number of colony-forming units in cow, rabbit, chicken, and goat fecal samples were 3.83 × 10(9), 1.03 × 10(9), 8.3 × 10(8), and 3.25 × 10(8) cells/ml, respectively. Forty-two colonies from the animal fecal samples were screened for the ability to utilize CO/H(2). Ten of these 42 colonies were capable of utilizing CO/H(2). Five isolates from cow feces (samples 5, 6, 8, 16, and 22) were highly similar to previously unknown (homo)acetogen, while cow-7 has shown 99 % similarity with Acetobacterium sp. as acetogens. On the other hand, four isolates from chicken feces (samples 3, 8, 10, and 11) have also shown high CO/H(2) utilizing activity. Hence, it is expected that this research could be used as the basis for the rapid enrichment of (homo)acetogenic consortia from various environmental sources.

  9. Rapid in vivo determination of fluoroquinolones in cultured puffer fish (Takifugu obscurus) muscle by solid-phase microextraction coupled with liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Tang, Yijia; Xu, Jianqiao; Chen, Le; Qiu, Junlang; Liu, Yuan; Ouyang, Gangfeng

    2017-12-01

    Fluoroquinolones (FQs) are a group of antimicrobial agents that have been widely used for therapeutic purposes in clinical medicine for human and veterinary diseases, as well as in aquaculture production. Their residues, however, may survive in foods of animal origin, thus causing health risks for human. In this study, a rapid and sensitive method based on in vivo solid-phase microextraction (SPME) coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed to detect the residues of five FQs in cultured puffer fish (Takifugu obscurus). In vitro fiber evaluation experiment demonstrated that, compared with the thicker polydimethylsiloxane (PDMS) coating (165µm), the custom-made biocompatible C18-PAN fibers (45µm) exhibited much higher extraction efficiencies towards FQs (approximately 9-31 times). The custom-made C18-PAN coating also possessed excellent reproducibility in fish muscle with the intra-fiber relative standard deviations (RSDs) ranging from 11.2% to 14.3% (n = 6) and inter-fiber RSDs ranging from 13.1% to 16.1% (n = 6), which was suitable for in vivo sampling. The custom-made SPME fibers were subsequently applied to determine fluoroquinolones in dorsal-epaxial muscle of living puffer fish. The accuracies were verified through the comparison with traditional liquid extraction (LE) method, and the sensitivities were demonstrated to be satisfying with the limits of detection (LODs) ranging from 0.3ngg -1 to 1.5ngg -1 . In general, this study presented a convenient and high-efficient method to determine fluoroquinolones in puffer fish by in vivo sampling. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Coupling frontal elution paper chromatography with desorption corona beam ionization mass spectrometry for rapid analysis of chlorphenamine in herbal medicines and dietary supplements.

    Science.gov (United States)

    Huang, Yun-Qing; You, Jing-Qing; Zhang, Junsheng; Sun, Wenjian; Ding, Li; Feng, Yu-Qi

    2011-10-14

    We developed a convenient method by coupling frontal elution paper chromatography with desorption corona beam ionization mass spectrometry (DCBI-MS) for rapid determination of chlorphenamine added in herbal medicines or dietary supplements. In this method, the ethanol extract of the herbal products was spotted directly onto an isosceles triangular filter paper sheet, and then the paper sheet was developed under strong elution condition with the sample zone migrating at the solvent front. The analyte was finally condensed at the V-shaped tip which could then be placed under the visible plasma beam of DCBI for ionization. The overall procedure took less than 5 min. The frontal elution paper chromatography on a triangular plate used in this work improved the signal intensity of chlorphenamine by 30-fold due to the analyte condensing at the tip and the reduction of the background suppression. Furthermore, the paper sheet also functioned as a filter in the analysis of solid or powder samples, which can increase the analytical throughput by omitting the step of centrifugation. The proposed method in current study was successfully applied in the determination of chlorphenamine in herbal medicines. Chlorphenamine was detected in four of the twelve types of herbal medicines examined in this study. The limit of detection was 200 ng/mL (2.0 ng absolute) in full-scan positive-ion mode and the linear range was from 5.0 μg/mL to 50 μg/mL with satisfactory linear coefficient (R(2) (the square of the correlation coefficient)=0.895). Good reproducibility was achieved with relative standard deviations (RSDs) less than 15.0% and the recoveries of chlorphenamine ranged from 84.3 to 90.6%. Copyright © 2011 Elsevier B.V. All rights reserved.

  11. Rapid Quantitation of Ascorbic and Folic Acids in SRM 3280 Multivitamin/Multielement Tablets using Flow-Injection Tandem Mass Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Bhandari, Deepak [ORNL; Kertesz, Vilmos [ORNL; Van Berkel, Gary J [ORNL

    2013-01-01

    RATIONALE: Ascorbic acid (AA) and folic acid (FA) are water-soluble vitamins and are usually fortified in food and dietary supplements. For the safety of human health, proper intake of these vitamins is recommended. Improvement in the analysis time required for the quantitative determination of these vitamins in food and nutritional formulations is desired. METHODS: A simple and fast (~5 min) in-tube sample preparation was performed, independently for FA and AA, by mixing extraction solvent with a powdered sample aliquot followed by agitation, centrifugation, and filtration to recover an extract for analysis. Quantitative detection was achieved by flow-injection (1 L injection volume) electrospray ionization tandem mass spectrometry (ESI-MS/MS) in negative ion mode using the method of standard addition. RESULTS: Method of standard addition was employed for the quantitative estimation of each vitamin in a sample extract. At least 2 spiked and 1 non-spiked sample extract were injected in triplicate for each quantitative analysis. Given an injection-to-injection interval of approximately 2 min, about 18 min was required to complete the quantitative estimation of each vitamin. The concentration values obtained for the respective vitamins in the standard reference material (SRM) 3280 using this approach were within the statistical range of the certified values provided in the NIST Certificate of Analysis. The estimated limit of detections of FA and AA were 13 and 5.9 ng/g, respectively. CONCLUSIONS: Flow-injection ESI-MS/MS was successfully applied for the rapid quantitation of FA and AA in SRM 3280 multivitamin/multielement tablets.

  12. Reliable and reproducible method for rapid identification of Nocardia species by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

    Science.gov (United States)

    Toyokawa, Masahiro; Kimura, Keigo; Nishi, Isao; Sunada, Atsuko; Ueda, Akiko; Sakata, Tomomi; Asari, Seishi

    2013-01-01

    Recently, matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) has been challenged for the identification of Nocardia species. However, the standard ethanol-formic acid extraction alone is insufficient in allowing the membrane proteins of Nocardia species to be ionized by the matrix. We therefore aimed to establish our new extraction method for the MALDI-TOF MS-based identification of Nocardia species isolates. Our modified extraction procedure is through dissociation in 0.5% Tween-20 followed by bacterial heat-inactivation, mechanical breaking of the cell wall by acid-washed glass beads and protein extraction with formic acid and acetonitrile. As reference methods for species identification, full-length 16S rRNA gene sequencing and some phenotypical tests were used. In a first step, we made our own Nocardia database by analyzing 13 strains (13 different species including N. elegans, N. otitidiscaviarum, N. asiatica, N. abscessus, N. brasiliensis, N. thailandica, N. farcinica, N. nova, N. mikamii, N. cyriacigeorgica, N. asteroids, Nocardiopsis alba, and Micromonospora sp.) and registered to the MALDI BioTyper database. Then we established our database. The analysis of 12 challenge strains using the our database gave a 100% correct identification, including 8 strains identified to the species level and 4 strains to the genus level (N. elegans, N. nova, N. farcinica, Micromonospora sp.) according to the manufacture's log score specifications. In the estimation of reproducibility of our method intended for 4 strains, both within-run and between-run reproducibility were excellent. These data indicates that our method for rapid identification of Nocardia species is with reliability, reproducibility and cost effective.

  13. Development of new efficient method for isolation of phenolics from sea algae prior to their rapid resolution liquid chromatographic-tandem mass spectrometric determination.

    Science.gov (United States)

    Klejdus, Bořivoj; Plaza, Merichel; Šnóblová, Marie; Lojková, Lea

    2017-02-20

    The extraction of phenolic compounds from 4 different sea algae samples, three brown algae (Cystoseira abies-marina, C. abies-marina grinded under cryogenic conditions with liquid nitrogen, Undaria pinnatifida and Sargassum muticum) and one red algae (Chondrus crispus) via solid phase extraction using micro-elution solid-phase extraction (μ-SPE) plate method was studied. Prior to μ-SPE, 50mg of algae with 80% methanol mixture was extracted in hyphenated series by various extraction techniques, such as pressurized liquid extraction and Ika Ultra-Turrax® Tube Drive, in combination with ultrasound assisted extraction. The μ-SPE plate technique reduced the time of sample pre-treatment thanks to higher sensitivity and pre-concentration effect. Selected groups of benzoic acid derivatives (p-hydroxybenzoic, protocatechuic, gallic, vanillic, and syringic acids), hydroxybenzaldehydes (4-hydroxybenzaldehyde, and 3,4-dihydroxybenzaldehyde), and cinnamic acid derivatives (p-coumaric, caffeic, ferulic, sinapic, and chlorogenic acids) were determined using rapid resolution liquid chromatography coupled to mass spectrometry detection with negative ion electrospray ionization (RRLC-ESI-MS) using multiple reactions monitoring. LOQs of measured samples varied in the range 0.23-1.68ng/mL and LODs in the range 0.07-0.52ng/mL. The applied method allowed a simultaneous determination of phenolics (i.e. free, esters soluble in methanol, glycosides, and esters insoluble in methanol) in less than 5min (including alkaline or acidic hydrolysis of raw extracts) from sea algae extracts. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Impact of rapid microbial identification directly from positive blood cultures using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry on patient management.

    Science.gov (United States)

    Martiny, D; Debaugnies, F; Gateff, D; Gérard, M; Aoun, M; Martin, C; Konopnicki, D; Loizidou, A; Georgala, A; Hainaut, M; Chantrenne, M; Dediste, A; Vandenberg, O; Van Praet, S

    2013-12-01

    For septic patients, delaying the initiation of antimicrobial therapy or choosing an inappropriate antibiotic can considerably worsen their prognosis. This study evaluated the impact of rapid microbial identification (RMI) from positive blood cultures on the management of patients with suspected sepsis. During a 6-month period, RMI by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was performed for all new episodes of bacteraemia. For each patient, the infectious disease specialist was contacted and questioned about his therapeutic decisions made based on the Gram staining and the RMI. This information was collected to evaluate the number of RMIs that led to a therapeutic change or to a modification of the patient's general management (e.g. fast removal of infected catheters). During the study period, 277 new episodes of bacteraemia were recorded. In 71.12% of the cases, MALDI-TOF MS resulted in a successful RMI (197/277). For adult and paediatric patients, 13.38% (21/157) and 2.50% (1/40) of the RMIs, respectively, resulted in modification of the treatment regimen, according to the survey. In many other cases, the MALDI-TOF MS was a helpful tool for infectious disease specialists because it confirmed suspected cases of contamination, especially in the paediatric population (15/40 RMIs, 37.50%), or suggested complementary diagnostic testing. This study emphasizes the benefits of RMI from positive blood cultures. Although the use of this technique represents an extra cost for the laboratory, RMI using MALDI-TOF MS has been implemented in our daily practice. © 2013 The Authors Clinical Microbiology and Infection © 2013 European Society of Clinical Microbiology and Infectious Diseases.

  15. Rapid determination of 9 aromatic amines in mainstream cigarette smoke by modified dispersive liquid liquid microextraction and ultraperformance convergence chromatography tandem mass spectrometry.

    Science.gov (United States)

    Deng, Huimin; Yang, Fei; Li, Zhonghao; Bian, Zhaoyang; Fan, Ziyan; Wang, Ying; Liu, Shanshan; Tang, Gangling

    2017-07-21

    Aromatic amines in mainstream cigarette smoke have long been monitored due to their carcinogenic toxicity. In this work, a reliable and rapid method was developed for the simultaneous determination of 9 aromatic amines in mainstream cigarette smoke by modified dispersive liquid liquid microextraction (DLLME) and ultraperformance convergence chromatography tandem mass spectrometry (UPC2-MS/MS). Briefly, the particulate phase of the cigarette smoke was captured by a Cambridge filter pad, and diluted hydrogen chloride aqueous solution is employed to extract the aromatic amines under mechanical shaking. After alkalization with sodium hydroxide solution, small amount of toluene was introduced to further extract and enrich aromatic amines by modified DLLME under vortexing. After centrifugation, toluene phase was purified by a universal QuEChERS cleanup kit and was finally analyzed by UPC2-MS/MS. Attributing to the superior performance of UPC2-MS/MS, this novel approach allowed the separation and determination of 9 aromatic amines within 5.0min with satisfactory resolution and sensitivity. The proposed method was finally validated using Kentucky reference cigarette 3R4F, and emission levels of targeted aromatic amines determined were comparable to previously reported methods At three different spiked levels, the recoveries of most analytes were ranged from 74.01% to 120.50% with relative standard deviation (RSD) less than 12%, except that the recovery of p-toluidine at low spiked level and 3-aminobiphenyl at medium spiked level was 62.77% and 69.37% respectively. Thus, this work provides a novel alternative method for the simultaneous analysis of 9 aromatic amines in mainstream cigarette smoke. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Rapid in vivo determination of tetrodotoxin in pufferfish (Fugu) muscle by solid-phase microextraction coupled to high-performance liquid chromatography tandem mass spectrometry.

    Science.gov (United States)

    Chen, Le; Qiu, Junlang; Tang, Yijia; Xu, Jianqiao; Huang, Shuyao; Liu, Yuan; Ouyang, Gangfeng

    2017-08-15

    Tetrodotoxin (TTX) is one of the most toxic substances of non-protein in nature. In present study, a rapid and sensitive method based on in vivo solid-phase microextraction (SPME) coupled to liquid chromatography tandem mass spectrometry (LC-MS/MS) was developed to detect the endogenous TTX in pufferfish (Fugu). Fiber evaluation experiments demonstrated that, compared with the commercial PDMS and PA fibers, the home-made electrospun PS@PDA-GA fibers exhibited much better extraction performance towards to TTX in water (120 times and 20 times, respectively), under the optimized conditions. Then, the home-made SPME fibers were employed to extract TTX in spiked homogeneous fish muscle samples, and a LC-MS-MS was used for the analysis. The reproducibilities (RSDs of inter and intra fiber were 12.1%, and 7.9% respectively), linear range (10-1000ngg-1, R2=0.9963) and sensitivity (the LOD was 2.3ngg-1) of the method were found to be excellent and satisfactory for further in vivo experiments. Especially the LOD of the established method is lower than the National Standard Method of China (GB/T 23217-2008, LOD 50ngg-1). Subsequently, the method was successfully applied to detect the TTX in the dorsal muscle of living pufferfish, and the accuracy was verified with traditional liquid extraction (LE) method. In general, this is the first study to detect TTX in pufferfish by in vivo sampling method, which provided a promising alternative method for the studies of TTX, and also advanced the implementation of SPME for more in vivo studies. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Evaluation of a New Ensemble Learning Framework for Mass Classification in Mammograms.

    Science.gov (United States)

    Rahmani Seryasat, Omid; Haddadnia, Javad

    2017-05-22

    Mammography is the most common screening method for diagnosis of breast cancer. In this study, a computer-aided system for diagnosis of benignity and malignity of the masses was implemented in mammogram images. In the computer aided diagnosis system, we first reduce the noise in the mammograms using an effective noise removal technique. After the noise removal, the mass in the region of interest must be segmented and this segmentation is done using a deformable model. After the mass segmentation, a number of features are extracted from it. These features include: features of the mass shape and border, tissue properties, and the fractal dimension. After extracting a large number of features, a proper subset must be chosen from among them. In this study, we make use of a new method on the basis of a genetic algorithm for selection of a proper set of features. After determining the proper features, a classifier is trained. To classify the samples, a new architecture for combination of the classifiers is proposed. In this architecture, easy and difficult samples are identified and trained using different classifiers. Finally, the proposed mass diagnosis system was also tested on mini-Mammographic Image Analysis Society and digital database for screening mammography databases. The obtained results indicate that the proposed system can compete with the state-of-the-art methods in terms of accuracy. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. A Guide to the Use of Mass Instruction Techniques. Teaching and Learning in Higher Education, 3.

    Science.gov (United States)

    Ellington, Henry

    This booklet is the first of three sequels to "A Guide to the Selection of Instructional Methods." Following a brief introduction, a discussion of the most common methods used in mass instructional techniques deals with the strenghts and weaknesses of lectures and similar expository techniques, film and video presentations, educational broadcasts,…

  19. Testing Hypothesized Psychosocial Mediators: Lessons Learned in the MassBUILT Study

    Science.gov (United States)

    Okechukwu, Cassandra A.; Krieger, Nancy; Sorensen, Glorian; Li, Yi; Barbeau, Elizabeth M.

    2011-01-01

    Only a few of the interventions that target blue-collar workers have conducted formal analysis to evaluate the specific attributes of their intervention that are associated with success or failure. This study examined the role of dual hazard and decisional balance in the MassBUILT smoking cessation intervention. The authors conducted sets of…

  20. Active learning for convenient annotation and classification of secondary ion mass spectrometry images

    NARCIS (Netherlands)

    Hanselmann, M.; Röder, J.; Köthe, U.; Renard, B.Y.; Heeren, R.M.A.|info:eu-repo/dai/nl/105188476; Hamprecht, F.A.

    2013-01-01

    Digital staining for the automated annotation of mass spectrometry imaging (MSI) data has previously been achieved using state-of-the-art classifiers such as random forests or support vector machines (SVMs). However, the training of such classifiers requires an expert to label exemplary data in

  1. Mass spectrometry

    DEFF Research Database (Denmark)

    Nyvang Hartmeyer, Gitte; Jensen, Anne Kvistholm; Böcher, Sidsel

    2010-01-01

    Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) is currently being introduced for the rapid and accurate identification of bacteria. We describe 2 MALDI-TOF MS identification cases - 1 directly on spinal fluid and 1 on grown bacteria. Rapidly obtained r...

  2. Rapid identification of bacillus anthracis spores in suspicious powder samples by using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS)

    NARCIS (Netherlands)

    Dybwad, M.; Laaken, A.L. van der; Blatny, J.M.; Paauw, A.

    2013-01-01

    Rapid and reliable identification of Bacillus anthracis spores in suspicious powders is important to mitigate the safety risks and economic burdens associated with such incidents. The aim of this study was to develop and validate a rapid and reliable laboratory- based matrix-assisted laser

  3. The Origins of Word Learning: Brain Responses of 3-Month-Olds Indicate Their Rapid Association of Objects and Words

    Science.gov (United States)

    Friedrich, Manuela; Friederici, Angela D.

    2017-01-01

    The present study explored the origins of word learning in early infancy. Using event-related potentials (ERP) we monitored the brain activity of 3-month-old infants when they were repeatedly exposed to several initially novel words paired consistently with each the same initially novel objects or inconsistently with different objects. Our results…

  4. Rapid identification of microorganisms from positive blood cultures by MALDI-TOF mass spectrometry subsequent to very short-term incubation on solid medium.

    Science.gov (United States)

    Idelevich, E A; Schüle, I; Grünastel, B; Wüllenweber, J; Peters, G; Becker, K

    2014-10-01

    Rapid identification of the causative microorganism is important for appropriate antimicrobial therapy of bloodstream infections. Bacteria from positive blood culture (BC) bottles are not readily available for identification by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). Lysis and centrifugation procedures suggested for direct MALDI-TOF MS from positive BCs without previous culture are associated with additional hands-on processing time and costs. Here, we describe an alternative approach applying MALDI-TOF MS from bacterial cultures incubated very briefly on solid medium. After plating of positive BC broth on Columbia blood agar (n = 165), MALDI-TOF MS was performed after 1.5, 2, 3, 4, 5, 6, 7, 8, 12 and (for control) 24 h of incubation until reliable identification to the species level was achieved (score ≥2.0). Mean incubation time needed to achieve species-level identification was 5.9 and 2.0 h for Gram-positive aerobic cocci (GPC, n = 86) and Gram-negative aerobic rods (GNR, n = 42), respectively. Short agar cultures with incubation times ≤2, ≤4, ≤6, ≤8 and ≤12 h yielded species identification in 1.2%, 18.6%, 64.0%, 96.5%, 98.8% of GPC, and in 76.2%, 95.2%, 97.6%, 97.6%, 97.6% of GNR, respectively. Control species identification at 24 h was achieved in 100% of GPC and 97.6% of GNR. Ethanol/formic acid protein extraction performed for an additional 34 GPC isolates cultivated from positive BCs showed further reduction in time to species identification (3.1 h). MALDI-TOF MS using biomass subsequent to very short-term incubation on solid medium allows very early and reliable bacterial identification from positive BCs without additional time and cost expenditure. © 2014 The Authors Clinical Microbiology and Infection © 2014 European Society of Clinical Microbiology and Infectious Diseases.

  5. Rapid Quantitative Chiral Amphetamines Liquid Chromatography-Tandem Mass Spectrometry Method in Plasma and Oral Fluid with a Cost-effective Chiral Derivatizing Reagent

    Science.gov (United States)

    Newmeyer, Matthew N.; Concheiro, Marta; Huestis, Marilyn A.

    2014-01-01

    Methamphetamine is a widely abused psychostimulant containing a chiral center. Consumption of over-the-counter and prescription medications may yield positive amphetamines results, but chiral separation of l- and d- methamphetamine and its metabolite amphetamine can help determine whether the source was licit or illicit. We present the first LC-MS/MS method with precolumn derivatization for methamphetamine and amphetamine chiral resolution in plasma and oral fluid collected with the Oral-Eze® and Quantisal™ devices. To 0.5 mL plasma, 0.75 mL Oral-Eze, or 1 mL Quantisal specimen racemic d11-methamphetamine and amphetamine internal standards were added, followed by protein precipitation. Samples were centrifuged and supernatants loaded onto pre-conditioned Phenomenex® Strata™-XC Polymeric Strong Cation solid phase extraction columns. After washing, analytes were eluted with 5% ammonium hydroxide in methanol. The eluate was evaporated to dryness and reconstituted in water. Derivatization was performed with 1-fluoro-2,4-dinitrophenyl-5-l-alanineamide (Marfey's reagent) and heating at 45°C for 1 h. Derivatized enantiomer separations were performed under isocratic conditions (methanol:water, 60:40) with a Phenomenex® Kinetex® 2.6 μm C18 column. Analytes were identified and quantified by two MRM transitions and their ratio on a 3200 QTrap (AB Sciex) mass spectrometer in ESI negative mode. In all three matrices, the method was linear for all enantiomers from 1-500 μg/L, with imprecision and accuracy of ≤11.3% and 85.3-108%, respectively. Extraction efficiencies ranged from 67.4-117% and matrix effects from -17.0-468%, with variation always ≤19.1%. Authentic plasma and OF specimens were collected from an IRB-approved study that included controlled Vicks® VapoInhaler™ administration. The present method is sensitive, selective, economic and rapid (separations accomplished in <10 min), and improves methamphetamine result interpretation. PMID:25065924

  6. Rapid quantitative chiral amphetamines liquid chromatography-tandem mass spectrometry: method in plasma and oral fluid with a cost-effective chiral derivatizing reagent.

    Science.gov (United States)

    Newmeyer, Matthew N; Concheiro, Marta; Huestis, Marilyn A

    2014-09-05

    Methamphetamine is a widely abused psychostimulant containing a chiral center. Consumption of over-the-counter and prescription medications may yield positive amphetamines results, but chiral separation of l- and d-methamphetamine and its metabolite amphetamine can help determine whether the source was licit or illicit. We present the first LC-MS/MS method with precolumn derivatization for methamphetamine and amphetamine chiral resolution in plasma and oral fluid collected with the Oral-Eze(®) and Quantisal™ devices. To 0.5mL plasma, 0.75mL Oral-Eze, or 1mL Quantisal specimen racemic d11-methamphetamine and amphetamine internal standards were added, followed by protein precipitation. Samples were centrifuged and supernatants loaded onto pre-conditioned Phenomenex(®) Strata™-XC Polymeric Strong Cation solid phase extraction columns. After washing, analytes were eluted with 5% ammonium hydroxide in methanol. The eluate was evaporated to dryness and reconstituted in water. Derivatization was performed with 1-fluoro-2,4-dinitrophenyl-5-l-alanineamide (Marfey's reagent) and heating at 45°C for 1h. Derivatized enantiomer separations were performed under isocratic conditions (methanol:water, 60:40) with a Phenomenex(®) Kinetex(®) 2.6μm C18 column. Analytes were identified and quantified by two MRM transitions and their ratio on a 3200 QTrap (AB Sciex) mass spectrometer in ESI negative mode. In all three matrices, the method was linear for all enantiomers from 1 to 500μg/L, with imprecision and accuracy of ≤11.3% and 85.3-108%, respectively. Extraction efficiencies ranged from 67.4 to 117% and matrix effects from -17.0 to 468%, with variation always ≤19.1%. Authentic plasma and OF specimens were collected from an IRB-approved study that included controlled Vicks(®) VapoInhaler™ administration. The present method is sensitive, selective, economic and rapid (separations accomplished in <10min), and improves methamphetamine result interpretation. Published

  7. Gram-stain plus MALDI-TOF MS (Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry for a rapid diagnosis of urinary tract infection.

    Directory of Open Access Journals (Sweden)

    Almudena Burillo

    Full Text Available Microbiological confirmation of a urinary tract infection (UTI takes 24-48 h. In the meantime, patients are usually given empirical antibiotics, sometimes inappropriately. We assessed the feasibility of sequentially performing a Gram stain and MALDI-TOF MS mass spectrometry (MS on urine samples to anticipate clinically useful information. In May-June 2012, we randomly selected 1000 urine samples from patients with suspected UTI. All were Gram stained and those yielding bacteria of a single morphotype were processed for MALDI-TOF MS. Our sequential algorithm was correlated with the standard semiquantitative urine culture result as follows: Match, the information provided was anticipative of culture result; Minor error, the information provided was partially anticipative of culture result; Major error, the information provided was incorrect, potentially leading to inappropriate changes in antimicrobial therapy. A positive culture was obtained in 242/1000 samples. The Gram stain revealed a single morphotype in 207 samples, which were subjected to MALDI-TOF MS. The diagnostic performance of the Gram stain was: sensitivity (Se 81.3%, specificity (Sp 93.2%, positive predictive value (PPV 81.3%, negative predictive value (NPV 93.2%, positive likelihood ratio (+LR 11.91, negative likelihood ratio (-LR 0.20 and accuracy 90.0% while that of MALDI-TOF MS was: Se 79.2%, Sp 73.5, +LR 2.99, -LR 0.28 and accuracy 78.3%. The use of both techniques provided information anticipative of the culture result in 82.7% of cases, information with minor errors in 13.4% and information with major errors in 3.9%. Results were available within 1 h. Our serial algorithm provided information that was consistent or showed minor errors for 96.1% of urine samples from patients with suspected UTI. The clinical impacts of this rapid UTI diagnosis strategy need to be assessed through indicators of adequacy of treatment such as a reduced time to appropriate empirical treatment or

  8. Building a rapid learning health care system for oncology: the regulatory framework of CancerLinQ.

    Science.gov (United States)

    Schilsky, Richard L; Michels, Dina L; Kearbey, Amy H; Yu, Peter Paul; Hudis, Clifford A

    2014-08-01

    Today is a time of unprecedented opportunity and challenge in health care generally and cancer care in particular. An explosion of scientific knowledge, the rapid introduction of new drugs and technologies, and the unprecedented escalation in the cost of health care challenge physicians to quickly assimilate new information and appropriately deploy new advances while also delivering efficient and high-quality care to a rapidly growing and aging patient population. At the same time, big data, with its potential to drive rapid understanding and innovation, promises to transform the health care industry, as it has many others already. CancerLinQ is an initiative of the American Society of Clinical Oncology (ASCO) and its Institute for Quality, developed to build on these opportunities and address these challenges by collecting information from the electronic health records of large numbers of patients with cancer. CancerLinQ is, first and foremost, a quality measurement and reporting system through which oncologists can harness the depth and power of their patients' clinical records and other data to improve the care they deliver. The development and deployment of CancerLinQ raises many important questions about the use of big data in health care. This article focuses on the US federal regulatory pathway by which CancerLinQ will accept patient records and the approach of ASCO toward stewardship of the information. © 2014 by American Society of Clinical Oncology.

  9. Exploiting machine learning algorithms for tree species classification in a semiarid woodland using RapidEye image

    Science.gov (United States)

    Adelabu, Samuel; Mutanga, Onisimo; Adam, Elhadi; Cho, Moses Azong

    2013-01-01

    Classification of different tree species in semiarid areas can be challenging as a result of the change in leaf structure and orientation due to soil moisture constraints. Tree species mapping is, however, a key parameter for forest management in semiarid environments. In this study, we examined the suitability of 5-band RapidEye satellite data for the classification of five tree species in mopane woodland of Botswana using machine leaning algorithms with limited training samples.We performed classification using random forest (RF) and support vector machines (SVM) based on EnMap box. The overall accuracies for classifying the five tree species was 88.75 and 85% for both SVM and RF, respectively. We also demonstrated that the new red-edge band in the RapidEye sensor has the potential for classifying tree species in semiarid environments when integrated with other standard bands. Similarly, we observed that where there are limited training samples, SVM is preferred over RF. Finally, we demonstrated that the two accuracy measures of quantity and allocation disagreement are simpler and more helpful for the vast majority of remote sensing classification process than the kappa coefficient. Overall, high species classification can be achieved using strategically located RapidEye bands integrated with advanced processing algorithms.

  10. Growing Renal Mass: Lessons Learned on the Road From an Atypical Presentation to Successful Therapy

    Directory of Open Access Journals (Sweden)

    Eliza Lamin

    2015-09-01

    Full Text Available A 25 4/7 week boy was born with a prenatal diagnosis of polyhydramnios and enlarged left kidney. Over the next 2 months serial ultrasounds demonstrated abnormal growth of the kidney, with 28.9% split function. At gestational age 39 4/7, he underwent a left radical nephrectomy. Pathology revealed congenital mesoblastic nephroma with mixed classic and cellular features. This case was puzzling due to prenatally diagnosed renal enlargement in a premature infant and inconclusive post-natal ultrasonographic imaging. Although the patient had paraneoplastic signs of polyhydramnios and hypertension, the mass did not have a classic appearance of CMN; possibly due to severe prematurity.

  11. Neutral fragment filtering for rapid identification of new diester-diterpenoid alkaloids in roots of Aconitum carmichaeli by ultra-high-pressure liquid chromatography coupled with linear ion trap-orbitrap mass spectrometry.

    Directory of Open Access Journals (Sweden)

    Jing Zhang

    Full Text Available A rapid and effective method was developed for separation and identification of diester-diterpenoid alkaloids (DDA in the roots of Aconitum carmichaeli by ultra-high-pressure liquid chromatography coupled with high resolution LTQ-Orbitrap tandem mass spectrometry (UHPLC-LTQ-Orbitrap-MS(n. According to accurate mass measurement and the characteristic neutral loss filtering strategy, a total of 42 diester-diterpenoid alkaloids (DDA were rapidly detected and characterized or tentatively identified. Meanwhile, the proposed fragmentation pathways and the major diagnostic fragment ions of aconitine, mesaconitine and hypaconitine were investigated to trace DDA derivatives in crude plant extracts. 23 potential new compounds were successfully screened and characterized in Aconitum carmichaeli, including 16 short chain fatty acyls DDA, 4 N-dealkyl DDA and several isomers of aconitine, mesaconitine and hypaconitine.

  12. Postural Motor Learning Deficits in People With MS in Spatial but Not Temporal Control of Center of Mass.

    Science.gov (United States)

    Gera, Geetanjali; Fling, Brett W; Van Ooteghem, Karen; Cameron, Michelle; Frank, James S; Horak, Fay B

    2016-09-01

    Multiple sclerosis (MS) is associated with balance deficits resulting in falls and impaired mobility. Although rehabilitation has been recommended to address these balance deficits, the extent to which people with MS can learn and retain improvements in postural responses is unknown. To determine the ability of people with MS to improve postural control with surface perturbation training. A total of 24 patients with mild MS and 14 age-matched controls underwent postural control training with a set pattern of continuous, forward-backward, sinusoidal, and surface translations provided by a force platform. Postural control was then tested the following day for retention. The primary outcome measures were the relative phase and center-of-mass (CoM) gain between the body CoM and the platform motion. People with MS demonstrated similar improvements in acquiring and retaining changes in the temporal control of the CoM despite significant deficits in postural motor performance at the baseline. Both MS and control groups learned to anticipate the pattern of forward-backward perturbations, so body CoM shifted from a phase-lag (age-matched controls [CS] = -7.1 ± 1.3; MS = -12.9 ± 1.0) toward a phase-lead (CS = -0.7 ± 1.8; MS = -6.1 ± 1.4) relationship with the surface oscillations. However, MS patients were not able to retain the changes in the spatial control of the CoM acquired during training. People with MS have the capacity to improve use of a feed-forward postural strategy with practice and retain the learned behavior for temporal not spatial control of CoM, despite their significant postural response impairments. © The Author(s) 2015.

  13. An Ultra-Performance Liquid Chromatoghraphy-Tandem Mass Spectrometry (UPLC-MS/MS) Method for the Rapid and Sensitive Determination of Sulforaphane and Sulforaphane Nitrile in Brassica Vegetables

    OpenAIRE

    Alvarez Jubete, Laura; Smyth, Thomas J.; Valverde, Juan; Rai, Dilip K.; Barry-Ryan, Catherine

    2013-01-01

    A rapid UPLC-MS/MS method has been developed and validated for the simultaneous analysis of sulforaphane and sulforaphane nitrile from Brassica Oleracea L. This method was developed utilising an Acquity BEH C8 column with gradient elution combined with tandem mass spectrometry detection, using positive ion electrospray ionisation in multiple reaction monitoring (MRM) mode. The method was validated for linearity, sensitivity, precision, accuracy, matrix effects and recovery. The retention time...

  14. Visual Event-Related Potentials to Novel Objects Predict Rapid Word Learning Ability in 20-Month-Olds.

    Science.gov (United States)

    Borgström, Kristina; Torkildsen, Janne von Koss; Lindgren, Magnus

    In an event-related potentials (ERP) study, twenty-month-old children (n = 37) were presented with pseudowords to map to novel object referents in five presentations. Quicker attenuation of the visual Negative central component (Nc) to novel objects predicted a larger difference in N400 amplitude between congruous and incongruous presentations of pseudowords at test. Furthermore, better initial recognition of familiar objects (Nc difference between familiar and novel objects) predicted the strength of the N400 incongruity effect to the verbal labels of these real objects. This study presents novel evidence for a link between efficient visual processing of objects and word learning ability.

  15. Rapid and sensitive method for quantification of gestodene in human plasma as the oxime derivative by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and its application to bioequivalence study.

    Science.gov (United States)

    Saxena, Ashish; Gupta, Arun; Kasibhatta, Ravisekhar; Bob, Manoj; Kumar, V Praveen; Purwar, Bipin

    2014-01-15

    A rapid and sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method has been developed and validated for the estimation of gestodene in human plasma. Gestodene was extracted from human plasma by using solid-phase extraction technique. Gestodene D6 was used as the internal standard. An Acquity HSS-T3 column provided chromatographic separation of analytes followed by detection with mass spectrometry. The mass transition ion-pair was followed as m/z 326.2→124.1 for gestodene and m/z 332.3→129.1 for gestodene D6. The method involves a solid phase extraction from plasma, rapid derivatization with hydroxylamine to form oxime, simple gradient chromatographic conditions and mass spectrometric detection that enables detection at sub-picogram levels. The proposed method has been validated for a linear range of 50-11957pg/ml with a correlation coefficient≥0.9994. The intra-run and inter-run precision and accuracy were within 10%. The overall recoveries for gestodene and gestodene D6 were 62.02% and 67.57% respectively. The total run time was 4.0min. The developed method was applied for the determination of the pharmacokinetic parameters of gestodene following a single oral administration of a 2×0.06mg gestodene tablets in 10 healthy female volunteers. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. Measuring and Improving Value of Care in Oncology Practices: ASCO Programs from Quality Oncology Practice Initiative to the Rapid Learning System.

    Science.gov (United States)

    Jacobson, Joseph O; Neuss, Michael N; Hauser, Robert

    2012-01-01

    Rising cancer care costs are no longer sustainable. Medical oncologists must focus on providing the maximum value to their patients; improving short-term, intermediate and long-term outcomes; and managing overall costs. Accurate measurement of outcomes and overall cost is essential to informing providers and institutions and in the quest for continuous improvement in value. The ASCO Quality Oncology Practice Initiative (QOPI) is an excellent tool for sampling processes of care in medical oncology practices. To achieve the larger goal of improving the value of cancer care, ASCO is investing in the development of a Rapid Learning System, which will leverage emerging information technologies to more accurately measure outcomes (including those reported by the patient) and costs, resulting in highly efficient, effective, and safe cancer care.

  17. Rapid learning of magnetic compass direction by C57BL/6 mice in a 4-armed 'plus' water maze.

    Directory of Open Access Journals (Sweden)

    John B Phillips

    Full Text Available Magnetoreception has been demonstrated in all five vertebrate classes. In rodents, nest building experiments have shown the use of magnetic cues by two families of molerats, Siberian hamsters and C57BL/6 mice. However, assays widely used to study rodent spatial cognition (e.g. water maze, radial arm maze have failed to provide evidence for the use of magnetic cues. Here we show that C57BL/6 mice can learn the magnetic direction of a submerged platform in a 4-armed (plus water maze. Naïve mice were given two brief training trials. In each trial, a mouse was confined to one arm of the maze with the submerged platform at the outer end in a predetermined alignment relative to magnetic north. Between trials, the training arm and magnetic field were rotated by 180(° so that the mouse had to swim in the same magnetic direction to reach the submerged platform. The directional preference of each mouse was tested once in one of four magnetic field alignments by releasing it at the center of the maze with access to all four arms. Equal numbers of responses were obtained from mice tested in the four symmetrical magnetic field alignments. Findings show that two training trials are sufficient for mice to learn the magnetic direction of the submerged platform in a plus water maze. The success of these experiments may be explained by: (1 absence of alternative directional cues (2, rotation of magnetic field alignment, and (3 electromagnetic shielding to minimize radio frequency interference that has been shown to interfere with magnetic compass orientation of birds. These findings confirm that mice have a well-developed magnetic compass, and give further impetus to the question of whether epigeic rodents (e.g., mice and rats have a photoreceptor-based magnetic compass similar to that found in amphibians and migratory birds.

  18. Rapid Determination of Plutonium Isotopes in Environmental Samples Using Sequential Injection Extraction Chromatography and Detection by Inductively Coupled Plasma Mass Spectrometry

    DEFF Research Database (Denmark)

    Qiao, Jixin; Hou, Xiaolin; Roos, Per

    2009-01-01

    This article presents an automated method for the rapid determination of 239Pu and 240Pu in various environmental samples. The analytical method involves the in-line separation of Pu isotopes using extraction chromatography (TEVA) implemented in a sequential injection (SI) network followed by det...

  19. Rapid, portable and cost-effective yeast cell viability and concentration analysis using lensfree on-chip microscopy and machine learning

    KAUST Repository

    Feizi, Alborz

    2016-09-24

    Monitoring yeast cell viability and concentration is important in brewing, baking and biofuel production. However, existing methods of measuring viability and concentration are relatively bulky, tedious and expensive. Here we demonstrate a compact and cost-effective automatic yeast analysis platform (AYAP), which can rapidly measure cell concentration and viability. AYAP is based on digital in-line holography and on-chip microscopy and rapidly images a large field-of-view of 22.5 mm2. This lens-free microscope weighs 70 g and utilizes a partially-coherent illumination source and an opto-electronic image sensor chip. A touch-screen user interface based on a tablet-PC is developed to reconstruct the holographic shadows captured by the image sensor chip and use a support vector machine (SVM) model to automatically classify live and dead cells in a yeast sample stained with methylene blue. In order to quantify its accuracy, we varied the viability and concentration of the cells and compared AYAP\\'s performance with a fluorescence exclusion staining based gold-standard using regression analysis. The results agree very well with this gold-standard method and no significant difference was observed between the two methods within a concentration range of 1.4 × 105 to 1.4 × 106 cells per mL, providing a dynamic range suitable for various applications. This lensfree computational imaging technology that is coupled with machine learning algorithms would be useful for cost-effective and rapid quantification of cell viability and density even in field and resource-poor settings.

  20. Rapid, portable and cost-effective yeast cell viability and concentration analysis using lensfree on-chip microscopy and machine learning.

    Science.gov (United States)

    Feizi, Alborz; Zhang, Yibo; Greenbaum, Alon; Guziak, Alex; Luong, Michelle; Chan, Raymond Yan Lok; Berg, Brandon; Ozkan, Haydar; Luo, Wei; Wu, Michael; Wu, Yichen; Ozcan, Aydogan

    2016-11-01

    Monitoring yeast cell viability and concentration is important in brewing, baking and biofuel production. However, existing methods of measuring viability and concentration are relatively bulky, tedious and expensive. Here we demonstrate a compact and cost-effective automatic yeast analysis platform (AYAP), which can rapidly measure cell concentration and viability. AYAP is based on digital in-line holography and on-chip microscopy and rapidly images a large field-of-view of 22.5 mm2. This lens-free microscope weighs 70 g and utilizes a partially-coherent illumination source and an opto-electronic image sensor chip. A touch-screen user interface based on a tablet-PC is developed to reconstruct the holographic shadows captured by the image sensor chip and use a support vector machine (SVM) model to automatically classify live and dead cells in a yeast sample stained with methylene blue. In order to quantify its accuracy, we varied the viability and concentration of the cells and compared AYAP's performance with a fluorescence exclusion staining based gold-standard using regression analysis. The results agree very well with this gold-standard method and no significant difference was observed between the two methods within a concentration range of 1.4 × 105 to 1.4 × 106 cells per mL, providing a dynamic range suitable for various applications. This lensfree computational imaging technology that is coupled with machine learning algorithms would be useful for cost-effective and rapid quantification of cell viability and density even in field and resource-poor settings.

  1. The Cultural Dimensions of Freshwater Wetland Assessments: Lessons Learned from the Application of US Rapid Assessment Methods in France.

    Science.gov (United States)

    Gaucherand, Stéphanie; Schwoertzig, Eugénie; Clement, Jean-Christophe; Johnson, Brad; Quétier, Fabien

    2015-07-01

    Given the recent strengthening of wetland restoration and protection policies in France, there is need to develop rapid assessment methods that provide a cost-effective way to assess losses and gains of wetland functions. Such methods have been developed in the US and we tested six of them on a selection of contrasting wetlands in the Isère watershed. We found that while the methods could discriminate sites, they did not always give consistent rankings, thereby revealing the different assumptions they explicitly or implicitly incorporate. The US assessment methods commonly use notions of "old-growth" or "pristine" to define the benchmark conditions against which to assess wetlands. Any reference-based assessment developed in the US would need adaptation to work in the French context. This could be quite straightforward for the evaluation of hydrologic variables as scoring appears to be consistent with the best professional judgment of hydrologic condition made by a panel of French local experts. Approaches to rating vegetation condition and landscape context, however, would require substantial reworking to reflect a novel view of reference standard. Reference standard in the European context must include acknowledgement that many of the best condition and biologically important wetland types in France are the product of intensive, centuries-long management (mowing, grazing, etc.). They must also explicitly incorporate the recent trend in ecological assessment to focus particularly on the wetland's role in landscape-level connectivity. These context-specific, socio-cultural dimensions must be acknowledged and adjusted for when adapting or developing wetland assessment methods in new cultural contexts.

  2. Rapid Quantitative Analysis of Multiple Explosive-Compound Classes on a Single Instrument via Flow-Injection Analysis Tandem Mass Spectrometry

    Science.gov (United States)

    2017-03-20

    criminal  forensics,  [11]  rapid  sample screening, [12,13,14,15] and trace‐evidence chem‐ ical  imaging [16,17,18]. Explosives detection has also  pro ...date,  FIA‐ MS/MS  has  been  used  for  rapid  quantitative  analysis  of  pharmaceuticals  [33],  pesticides   [34], environmental con‐ taminants...the literature reference listed  in the reference section of this paper.    As shown  in the Table 3 FIA ESI/APCI MSMS  pro ‐ vides quick and sensitive

  3. Rapid activity-directed screening of estrogens by parallel coupling of liquid chromatography with a functional gene reporter assay and mass spectrometry

    NARCIS (Netherlands)

    Jonker, W.; Lamoree, M.H.; Houtman, C.J.; Hamers, T.; Somsen, G.W.; Kool, J.

    2015-01-01

    In this study we developed a new LC nanofractionation platform that combines a human cell (BG1.Luc) gene reporter assay with a high resolution mass spectrometer for the detection and identification of estrogenic and anti-estrogenic compounds in environmental waters. The selection of this assay was

  4. Energy dependence of acceptance-corrected dielectron excess mass spectrum at mid-rapidity in Au+Au collisions at sNN=19.6 and 200 GeV

    Directory of Open Access Journals (Sweden)

    L. Adamczyk

    2015-11-01

    Full Text Available The acceptance-corrected dielectron excess mass spectra, where the known hadronic sources have been subtracted from the inclusive dielectron mass spectra, are reported for the first time at mid-rapidity |yee|<1 in minimum-bias Au+Au collisions at sNN=19.6 and 200 GeV. The excess mass spectra are consistently described by a model calculation with a broadened ρ spectral function for Mee<1.1 GeV/c2. The integrated dielectron excess yield at sNN=19.6 GeV for 0.4rapidity, has a value similar to that in In+In collisions at sNN=17.3 GeV. For sNN=200 GeV, the normalized excess yield in central collisions is higher than that at sNN=17.3 GeV and increases from peripheral to central collisions. These measurements indicate that the lifetime of the hot, dense medium created in central Au+Au collisions at sNN=200 GeV is longer than those in peripheral collisions and at lower energies.

  5. Learning from a Rapid Health Impact Assessment of a proposed maternity service reconfiguration in the English NHS

    Directory of Open Access Journals (Sweden)

    Haroon Sophie

    2008-04-01

    Full Text Available Abstract Background Within many parts of the country, the NHS is undertaking reconfiguration of services. Such proposals can prove a tipping point and provoke public protest, often with significant involvement of local and national politicians. We undertook a rapid Health Impact Assessment (HIA of a proposed reconfiguration of maternity services in Huddersfield and Halifax in England. The aim of the HIA was to help the PCT Boards to assess the reconfiguration's possible consequences on access to maternity services, and maternal and infant health outcomes across different socio-economic groups in Kirklees. We report on the findings of the HIA and the usefulness of the process to decision making. Methods This HIA used routine maternity data for 2004–2005 in Huddersfield, in addition to published evidence. Standard HIA techniques were used. Results We re-highlighted the socio economic differences in smoking status at booking and quitting during pregnancy. We focused on the key concerns of the public, that of adverse obstetric events on a Midwife Led Unit (MLU with distant obstetric cover. We estimate that twenty percent of women giving birth in a MLU may require urgent transfer to obstetric care during labour. There were no significant socio economic differences. Much of the risk can be mitigated though robust risk management policies. Additional travelling distances and costs could affect lower socio-economic groups the greatest because of lower car ownership and geographical location in relation to the units. There is potential that with improved community antenatal and post natal care, population outcomes could improve significantly, the available evidence supports this view. Conclusion Available evidence suggests that maternity reconfiguration towards enhanced community care could have many potential benefits but carries risk. Investment is needed to realise the former and mitigate the latter. The usefulness of this Health Impact Assessment

  6. Development of a Rapid and Accurate Identification Method for Citrobacter Species Isolated from Pork Products Using a Matrix-Assisted Laser-Desorption Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS).

    Science.gov (United States)

    Kwak, Hye-Lim; Han, Sun-Kyung; Park, Sunghoon; Park, Si Hong; Shim, Jae-Yong; Oh, Mihwa; Ricke, Steven C; Kim, Hae-Yeong

    2015-09-01

    Previous detection methods for Citrobacter are considered time consuming and laborious. In this study, we have developed a rapid and accurate detection method for Citrobacter species in pork products, using matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry (MS). A total of 35 Citrobacter strains were isolated from 30 pork products and identified by both MALDI-TOF MS and 16S rRNA gene sequencing approaches. All isolates were identified to the species level by the MALDI-TOF MS, while 16S rRNA gene sequencing results could not discriminate them clearly. These results confirmed that MALDI-TOF MS is a more accurate and rapid detection method for the identification of Citrobacter species.

  7. Rapid Differentiation of Haemophilus influenzae and Haemophilus haemolyticus by Use of Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry with ClinProTools Mass Spectrum Analysis.

    Science.gov (United States)

    Chen, Jonathan H K; Cheng, Vincent C C; Wong, Chun-Pong; Wong, Sally C Y; Yam, Wing-Cheong; Yuen, Kwok-Yung

    2017-09-01

    Haemophilus influenzae is associated with severe invasive disease, while Haemophilus haemolyticus is considered part of the commensal flora in the human respiratory tract. Although the addition of a custom mass spectrum library into the matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) system could improve identification of these two species, the establishment of such a custom database is technically complicated and requires a large amount of resources, which most clinical laboratories cannot afford. In this study, we developed a mass spectrum analysis model with 7 mass peak biomarkers for the identification of H. influenzae and H. haemolyticus using the ClinProTools software. We evaluated the diagnostic performance of this model using 408 H. influenzae and H. haemolyticus isolates from clinical respiratory specimens from 363 hospitalized patients and compared the identification results with those obtained with the Bruker IVD MALDI Biotyper. The IVD MALDI Biotyper identified only 86.9% of H. influenzae (311/358) and 98.0% of H. haemolyticus (49/50) clinical isolates to the species level. In comparison, the ClinProTools mass spectrum model could identify 100% of H. influenzae (358/358) and H. haemolyticus (50/50) clinical strains to the species level and significantly improved the species identification rate (McNemar's test, P mass spectrometry to handle closely related bacterial species when the proprietary spectrum library failed. This approach should be useful for the differentiation of other closely related bacterial species. Copyright © 2017 American Society for Microbiology.

  8. Rapid fingerprinting of sterols and related compounds in vegetable and animal oils and phytosterol enriched- margarines by transmission mode direct analysis in real time mass spectrometry.

    Science.gov (United States)

    Alberici, Rosana M; Fernandes, Gabriel D; Porcari, Andréia M; Eberlin, Marcos N; Barrera-Arellano, Daniel; Fernández, Facundo M

    2016-11-15

    Plant-derived sterols, often referred to as phytosterols, are important constituents of plant membranes where they assist in maintaining phospholipid bilayer stability. Consumption of phytosterols has been suggested to positively affect human health by reducing cholesterol levels in blood via inhibition of its absorption in the small intestine, thus protecting against heart attack and stroke. Sterols are challenging analytes for mass spectrometry, since their low polarity makes them difficult to ionize by both electrospray ionization (ESI) and matrix-assisted laser desorption ionization (MALDI), typically requiring derivatization steps to overcome their low ionization efficiencies. We present a fast and reliable method to characterize the composition of phytosterols in vegetable oils and enriched margarines. The method requires no derivatization steps or sample extraction procedures thanks to the use of transmission mode direct analysis in real time mass spectrometry (TM-DART-MS). Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. A multiple-dimension liquid chromatography coupled with mass spectrometry data strategy for the rapid discovery and identification of unknown compounds from a Chinese herbal formula (Er-xian decoction).

    Science.gov (United States)

    Wang, Caihong; Zhang, Jinlan; Wu, Caisheng; Wang, Zhe

    2017-10-06

    It is very important to rapidly discover and identify the multiple components of traditional Chinese medicine (TCM) formula. High performance liquid chromatography with high resolution tandem mass spectrometry (HPLC-HRMS/MS) has been widely used to analyze TCM formula and contains multiple-dimension data including retention time (RT), high resolution mass (HRMS), multiple-stage mass spectrometric (MSn), and isotope intensity distribution (IID) data. So it is very necessary to exploit a useful strategy to utilize multiple-dimension data to rapidly probe structural information and identify chemical compounds. In this study, a new strategy to initiatively use the multiple-dimension LC-MS data has been developed to discover and identify unknown compounds of TCM in many styles. The strategy guarantees the fast discovery of candidate structural information and provides efficient structure clues for identification. The strategy contains four steps in sequence: (1) to discover potential compounds and obtain sub-structure information by the mass spectral tree similarity filter (MTSF) technique, based on HRMS and MSn data; (2) to classify potential compounds into known chemical classes by discriminant analysis (DA) on the basis of RT and HRMS data; (3) to hit the candidate structural information of compounds by intersection sub-structure between MTSF and DA (M,D-INSS); (4) to annotate and confirm candidate structures by IID data. This strategy allowed for the high exclusion efficiency (greater than 41%) of irrelevant ions in er-xian decoction (EXD) while providing accurate structural information of 553 potential compounds and identifying 66 candidates, therefore accelerating and simplifying the discovery and identification of unknown compounds in TCM formula. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Determination of red blood cell fatty acid profiles: Rapid and high-confident analysis by chemical ionization-gas chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Schober, Yvonne; Wahl, Hans Günther; Renz, Harald; Nockher, Wolfgang Andreas

    2017-01-01

    Cellular fatty acid (FA) profiles have been acknowledged as biomarkers in various human diseases. Nevertheless, common FA analysis by gas chromatography mass spectrometry (GC-MS) requires long analysis time. Hence, there is a need for feasible methods for high throughput analysis in clinical studies. FA was extracted from red blood cells (RBC) and derivatized to fatty acid methyl esters (FAME). A method using gas chromatography tandem mass spectrometry (GC-MS/MS) with ammonia-induced chemical ionization (CI) was developed for the analysis of FA profiles in human RBC. We compared this method with classical single GC-MS using electron impact ionization (EI). The FA profiles of 703 RBC samples were determined by GC-MS/MS. In contrast to EI ammonia-induced CI resulted in adequate amounts of molecular ions for further fragmentation of FAME. Specific fragments for confident quantification and fragmentation were determined for 45 FA. The GC-MS/MS method has a total run time of 9min compared to typical analysis times of up to 60min in conventional GC-MS. Intra and inter assay variations were Analysis of RBC FA composition revealed an age-dependent increase of the omega-3 eicosapentaenoic and docosahexaenoic acid, and a decline of the omega-6 linoleic acid with a corresponding rise of the omega-3 index. The combination of ammonia-induced CI and tandem mass spectrometry after GC separation allows for high-throughput, robust and confident analysis of FA profiles in the clinical laboratory. Copyright © 2016. Published by Elsevier B.V.

  11. Matrix-assisted laser desorption/ionization mass spectrometric imaging for the rapid segmental analysis of methamphetamine in a single hair using umbelliferone as a matrix.

    Science.gov (United States)

    Wang, Hang; Wang, Ying

    2017-07-04

    Segmental hair analysis offers a longer period for retrospective drug detection than blood or urine. Hair is a keratinous fiber and is strongly hydrophobic. The embedding of drugs in hydrophobic hair at low concentrations makes it difficult for extraction and detection with matrix-assisted laser desorption/ionization (MALDI) coupled with mass spectrometric imaging (MSI). In this study, a single scalp hair was longitudinally cut with a cryostat section to a length of 4 mm and fixed onto a stainless steel MALDI plate. Umbelliferone was used as a new hydrophobic matrix to enrich and assist the ionization efficiency of methamphetamine in the hair sample. MALDI-Fourier transform ion cyclotron resonance (FTICR)-MS profiling and imaging were performed for direct detection and mapping of methamphetamine on the longitudinal sections of the single hair sample in positive ion mode. Using MALDI-MSI, the distribution of methamphetamine was observed throughout five longitudinally sectioned hair samples from a drug abuser. The changes of methamphetamine were also semi-quantified by comparing the ratios of methamphetamine/internal standard (I.S). This method improves the detection sensitivity of target drugs embedded in a hair matrix for imaging with mass spectrometry. The method could provide a detection level of methamphetamine down to a nanogram per milligram incorporated into hair. The results were also compared with the conventional high performance liquid chromatography -tandem mass spectrometry (HPLC-MS/MS) method. Changes in the imaging results over time by the MSI method showed good semi-quantitative correlation to the results from the HPLC-MS/MS method. This study provides a powerful tool for drug abuse control and forensic medicine analysis in a narrow time frame, and a reduction in the sample amount required. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. An electrospray/inductively coupled plasma dual-source time-of-flight mass spectrometer for rapid metallomic and speciation analysis. Part 1. Molecular channel characterization.

    Science.gov (United States)

    Rogers, Duane A; Ray, Steven J; Hieftje, Gary M

    2010-04-01

    A new time-of-flight mass spectrometer has been developed that uses an electrospray source and an inductively coupled plasma to extract molecular, atomic, and isotopic information simultaneously from a single sample. This paper will focus on characterization of the ESI channel. Sensitivities are reported for hexadecyltrimethylammonium, tetrahexylammonium, tetraoctylammonium, myoglobin, insulin, cyanocobalamin, leucine enkephalin, and alcohol dehydrogenase. Skimmer-nozzle collisionally induced dissociation is explored for adduct removal and analyte fragmentation on the ESI channel for tetraoctylammonium ion and leucine enkephalin. Long-term and short-term spray stability is also examined.

  13. Desorption Electrospray Ionization Mass Spectrometry (DESI-MS) Analysis of Organophosphorus Chemical Warfare Agents: Rapid Acquisition of Time-Aligned Parallel (TAP) Fragmentation Data

    Science.gov (United States)

    2010-06-01

    Résumé …..... On a appliqué la méthode désorption - ionisation par électronébulisation - spectrométrie de masse (DESI-SM) pour l’analyse...2010-047, R & D pour la défense Canada – Suffield; Juin 2010. Introduction : On a appliqué la méthode désorption – ionisation par...132, 868-875. DRDC Suffield TM 2010-047 29 [26] Williams, J.P. and Scrivens, J.H. (2008). Coupling desorption electrospray ionisation with

  14. Rapid identification of positive blood cultures by matrix-assisted laser desorption ionization-time of flight mass spectrometry using prewarmed agar plates.

    Science.gov (United States)

    Bhatti, M M; Boonlayangoor, S; Beavis, K G; Tesic, V

    2014-12-01

    This study describes an inexpensive and straightforward method for identifying bacteria by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) directly from positive blood cultures using prewarmed agar plates. Different inoculation methods and incubation times were evaluated to determine the optimal conditions. The two methods using pelleted material from positive culture bottles performed best. In particular, the pellet streak method correctly identified 94% of the Gram negatives following 4 h of incubation and 98% of the Gram positives following 6 h of incubation. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  15. Rapid and simultaneous determination of neptunium and plutonium in environmental samples using anion exchange chromatographic and sequential injection setup combined with inductively coupled plasma mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Jixin Qiao; Hou, X.; Roos, P. (Technical Univ. of Denmark, Risoe National Lab. for Sustainable Energy. Radiation Research Div., Roskilde (Denmark)); Miro, M. (Univ. of the Balearic Islands, Dept. of Chemistry, Faculty of Sciences, Palma de Mallorca (Spain))

    2010-03-15

    Full text: This paper presents an automated analytical method for the rapid and simultaneous determination of Pu and Np in the environmental samples. Anion exchange chromatographic column was incorporated in a sequential injection system to actualize the automated separation of Pu isotpes along with 237Np from the matrix elements and interfering radionuclides. K{sub 2}S{sub 2}O{sub 5}-conc. HNO{sub 3} was applied as redox reagents for the valence adjustment and stabilization of Pu(IV) and Np(IV). 242Pu preformed well as a tracer for both Pu isotopes and 237Np. It was observed that the cross-link and particle size of the resins had significant effluence on the separation efficiency and anion exchange resin Bio-Rad AG 1 x 4 with the particle size of 100-200 mesh was chosen as the optimum. The investigation on the capacity showed small-sized column packed with 2mL resin sufficed up to 50g of soil sample, which provides an advantage of low consumption of the resin and low generation of acid waste after the column washing. The analytical results for Pu and Np in three reference materials showed good agreement with the certified or reference values at the 0.05 significance level. Chemical yields of Pu and Np equally range from 80% to 100%, and the decontamination factors for uranium, thorium and lead were in the range of 103 to 104. The total time of separation for a single sample was < 2.5 hours, which extremely improve the analysis efficiency and reduces the labor intensity, as well as enables a rapid determination of Pu and Np in emergency situations. (author)

  16. Rapid determination of anti-estrogens by gas chromatography/mass spectrometry in urine: Method validation and application to real samples

    Directory of Open Access Journals (Sweden)

    E. Gerace

    2012-02-01

    Full Text Available A fast screening protocol was developed for the simultaneous determination of nine anti-estrogenic agents (aminoglutethimide, anastrozole, clomiphene, drostanolone, formestane, letrozole, mesterolone, tamoxifen, testolactone plus five of their metabolites in human urine. After an enzymatic hydrolysis, these compounds can be extracted simultaneously from urine with a simple liquid–liquid extraction at alkaline conditions. The analytes were subsequently analyzed by fast-gas chromatography/mass spectrometry (fast-GC/MS after derivatization. The use of a short column, high-flow carrier gas velocity and fast temperature ramping produced an efficient separation of all analytes in about 4 min, allowing a processing rate of 10 samples/h. The present analytical method was validated according to UNI EN ISO/IEC 17025 guidelines for qualitative methods. The range of investigated parameters included the limit of detection, selectivity, linearity, repeatability, robustness and extraction efficiency. High MS-sampling rate, using a benchtop quadrupole mass analyzer, resulted in accurate peak shape definition under both scan and selected ion monitoring modes, and high sensitivity in the latter mode. Therefore, the performances of the method are comparable to the ones obtainable from traditional GC/MS analysis. The method was successfully tested on real samples arising from clinical treatments of hospitalized patients and could profitably be used for clinical studies on anti-estrogenic drug administration. Keywords: Anti-estrogens, Fast-GC/MS, Urine screening, Validation, Breast cancer

  17. Rapid determination of anti-estrogens by gas chromatography/mass spectrometry in urine: Method validation and application to real samples

    Science.gov (United States)

    Gerace, E.; Salomone, A.; Abbadessa, G.; Racca, S.; Vincenti, M.

    2011-01-01

    A fast screening protocol was developed for the simultaneous determination of nine anti-estrogenic agents (aminoglutethimide, anastrozole, clomiphene, drostanolone, formestane, letrozole, mesterolone, tamoxifen, testolactone) plus five of their metabolites in human urine. After an enzymatic hydrolysis, these compounds can be extracted simultaneously from urine with a simple liquid–liquid extraction at alkaline conditions. The analytes were subsequently analyzed by fast-gas chromatography/mass spectrometry (fast-GC/MS) after derivatization. The use of a short column, high-flow carrier gas velocity and fast temperature ramping produced an efficient separation of all analytes in about 4 min, allowing a processing rate of 10 samples/h. The present analytical method was validated according to UNI EN ISO/IEC 17025 guidelines for qualitative methods. The range of investigated parameters included the limit of detection, selectivity, linearity, repeatability, robustness and extraction efficiency. High MS-sampling rate, using a benchtop quadrupole mass analyzer, resulted in accurate peak shape definition under both scan and selected ion monitoring modes, and high sensitivity in the latter mode. Therefore, the performances of the method are comparable to the ones obtainable from traditional GC/MS analysis. The method was successfully tested on real samples arising from clinical treatments of hospitalized patients and could profitably be used for clinical studies on anti-estrogenic drug administration.

  18. Rapid identification of Vibrio parahaemolyticus isolated from shellfish, sea water and sediments of the Khnifiss lagoon, Morocco, by MALDI-TOF mass spectrometry.

    Science.gov (United States)

    Malainine, S M; Moussaoui, W; Prévost, G; Scheftel, J-M; Mimouni, R

    2013-05-01

    We establish the presence of Vibrio parahaemolyticus and deepen the comparison of isolates using MALDI-TOF MS for the typing of isolates originating from the Khnifiss lagoon (Morocco). Amongst 48 samples from sea water, sediment and shellfish isolated from different sites of Khnifiss lagoon, Morocco, we obtained 22 isolates of V. parahaemolyticus identified by Vitek 2™ System (bioMérieux) and MALDI Biotyper™ (Bruker Daltonics). All isolates were highly resistant to ampicillin and ticarcillin, moderately resistant to cefalotin, but sensitive to 16 other antimicrobials tested. MALDI-TOF MS was used to discriminate between closely related environmental strains of V. parahaemolyticus. A clustering and distribution based on MALDI-TOF spectra were generated using the BioTyper 1.1™ software. Despite low diversity in regard to the biochemical characteristics and antimicrobial resistance, the isolates evoke a larger biodiversity when analysed through mass spectra of abundant proteins. Different evaluations of a cut-off value showed that, when placed at a 10% threshold of the whole diversity, isolates differed by at least three mass peaks. © 2013 The Society for Applied Microbiology.

  19. Early Holocene (8.6 ka) rock avalanche deposits, Obernberg valley (Eastern Alps): Landform interpretation and kinematics of rapid mass movement.

    Science.gov (United States)

    Ostermann, Marc; Sanders, Diethard; Ivy-Ochs, Susan; Alfimov, Vasily; Rockenschaub, Manfred; Römer, Alexander

    2012-10-15

    In the Obernberg valley, the Eastern Alps, landforms recently interpreted as moraines are re-interpreted as rock avalanche deposits. The catastrophic slope failure involved an initial rock volume of about 45 million m³, with a runout of 7.2 km over a total vertical distance of 1330 m (fahrböschung 10°). 36Cl surface-exposure dating of boulders of the avalanche mass indicates an event age of 8.6 ± 0.6 ka. A 14C age of 7785 ± 190 cal yr BP of a palaeosoil within an alluvial fan downlapping the rock avalanche is consistent with the event age. The distal 2 km of the rock-avalanche deposit is characterized by a highly regular array of transverse ridges that were previously interpreted as terminal moraines of Late-Glacial. 'Jigsaw-puzzle structure' of gravel to boulder-size clasts in the ridges and a matrix of cataclastic gouge indicate a rock avalanche origin. For a wide altitude range the avalanche deposit is preserved, and the event age of mass-wasting precludes both runout over glacial ice and subsequent glacial overprint. The regularly arrayed transverse ridges thus were formed during freezing of the rock avalanche deposits.

  20. Diagnosis of breast masses from dynamic contrast-enhanced and diffusion-weighted MR: a machine learning approach.

    Directory of Open Access Journals (Sweden)

    Hongmin Cai

    Full Text Available PURPOSE: Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI is increasingly used for breast cancer diagnosis as supplementary to conventional imaging techniques. Combining of diffusion-weighted imaging (DWI of morphology and kinetic features from DCE-MRI to improve the discrimination power of malignant from benign breast masses is rarely reported. MATERIALS AND METHODS: The study comprised of 234 female patients with 85 benign and 149 malignant lesions. Four distinct groups of features, coupling with pathological tests, were estimated to comprehensively characterize the pictorial properties of each lesion, which was obtained by a semi-automated segmentation method. Classical machine learning scheme including feature subset selection and various classification schemes were employed to build prognostic model, which served as a foundation for evaluating the combined effects of the multi-sided features for predicting of the types of lesions. Various measurements including cross validation and receiver operating characteristics were used to quantify the diagnostic performances of each feature as well as their combination. RESULTS: Seven features were all found to be statistically different between the malignant and the benign groups and their combination has achieved the highest classification accuracy. The seven features include one pathological variable of age, one morphological variable of slope, three texture features of entropy, inverse difference and information correlation, one kinetic feature of SER and one DWI feature of apparent diffusion coefficient (ADC. Together with the selected diagnostic features, various classical classification schemes were used to test their discrimination power through cross validation scheme. The averaged measurements of sensitivity, specificity, AUC and accuracy are 0.85, 0.89, 90.9% and 0.93, respectively. CONCLUSION: Multi-sided variables which characterize the morphological, kinetic, pathological

  1. Ultra-high performance liquid chromatography with linear ion trap-Orbitrap hybrid mass spectrometry combined with a systematic strategy based on fragment ions for the rapid separation and characterization of components in Stellera chamaejasme extracts.

    Science.gov (United States)

    Wang, Zhixin; Qu, Yang; Wang, Li; Zhang, Xiaozhe; Xiao, Hongbin

    2016-04-01

    Stellera chamaejasme, a famous toxic herb, has been used in traditional Chinese medicine to treat various diseases. For decades, increasing attention in modern pharmacological studies has been drawn to S. chamaejasme because of its potential anti-tumor, anti-virus, and anti-fungus activities. However, due to the intrinsic complexity of chemical constitutes, hardly any investigations formed an overall recognition for the chemical profiles of this herb. In this study, a rapid and sensitive ultra-high performance liquid chromatography coupled with linear ion trap-Orbitrap mass spectrometry method was developed to characterize the chemical components of S. chamaejasme extracts. Based on optimized ultra-high performance liquid chromatography and mass spectrometry conditions and systematic fragment ions-based strategy, a total of 47 components including flavones, diterpenes, coumarins, and lignans were simultaneously detected and identified or tentatively identified for the first time. The MS(n) fragmentation patterns of all the characterized compounds in positive or negative electrospray ionization modes were also explored and summarized. These results provided essential data for further pharmacological research on S. chamaejasme. Moreover, the method was demonstrated to be an efficient tool for rapid qualitative analysis of secondary metabolites from natural resources. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Rapid Screening for Potential Epitopes Reactive with a Polycolonal Antibody by Solution-Phase H/D Exchange Monitored by FT-ICR Mass Spectrometry

    Science.gov (United States)

    Zhang, Qian; Noble, Kyle A.; Mao, Yuan; Young, Nicolas L.; Sathe, Shridhar K.; Roux, Kenneth H.; Marshall, Alan G.

    2013-07-01

    The potential epitopes of a recombinant food allergen protein, cashew Ana o 2, reactive to polyclonal antibodies, were mapped by solution-phase amide backbone H/D exchange (HDX) coupled with Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Ana o 2 polyclonal antibodies were purified in the serum from a goat immunized with cashew nut extract. Antibodies were incubated with recombinant Ana o 2 (rAna o 2) to form antigen:polyclonal antibody (Ag:pAb) complexes. Complexed and uncomplexed (free) rAna o 2 were then subjected to HDX-MS analysis. Four regions protected from H/D exchange upon pAb binding are identified as potential epitopes and mapped onto a homologous model.

  3. Orbital and physical parameters of eclipsing binaries from the All-Sky Automated Survey catalogue. III. Two new low-mass systems with rapidly evolving spots

    Science.gov (United States)

    Hełminiak, K. G.; Konacki, M.; Złoczewski, K.; Ratajczak, M.; Reichart, D. E.; Ivarsen, K. M.; Haislip, J. B.; Crain, J. A.; Foster, A. C.; Nysewander, M. C.; Lacluyze, A. P.

    2011-03-01

    Aims: We present the results of our spectroscopic and photometric analysis of two newly discovered low-mass detached eclipsing binaries found in the All-Sky Automated Survey (ASAS) catalogue: ASAS J093814-0104.4 and ASAS J212954-5620.1. Methods: Using the Grating Instrument for Radiation Analysis with a Fibre-Fed Echelle (GIRAFFE) on the 1.9-m Radcliffe telescope at the South African Astronomical Observatory (SAAO) and the University College London Echelle Spectrograph (UCLES) on the 3.9-m Anglo-Australian Telescope, we obtained high-resolution spectra of both objects and derived their radial velocities (RVs) at various orbital phases. The RVs of both objects were measured with the two-dimensional cross-correlation technique (TODCOR) using synthetic template spectra as references. We also obtained V and I band photometry using the 1.0-m Elizabeth telescope at SAAO and the 0.4-m Panchromatic Robotic Optical Monitoring and Polarimetry Telescopes (PROMPT) located at the Cerro Tololo Inter-American Observatory (CTIO). The orbital and physical parameters of the systems were derived with PHOEBE and JKTEBOP codes. We compared our results with several sets of widely-used isochrones. Results: Our multi-epoch photometric observations demonstrate that both objects show significant out-of-eclipse modulations, which vary in time. We believe that this effect is caused by stellar spots, which evolve on time scales of tens of days. For this reason, we constructed our models on the basis of photometric observations spanning short time scales (less than a month). Our modeling indicates that (1) ASAS J093814-0104.04 is a main sequence active system with nearly-twin components with masses of M1 = 0.771 ± 0.033 M⊙, M2 = 0.768 ± 0.021 M⊙ and radii of R1 = 0.772 ± 0.012 R⊙ and R2 = 0.769 ± 0.013 R⊙. (2) ASAS J212954-5620.1 is a main sequence active binary with component masses of M1 = 0.833 ± 0.017 M⊙, M2 = 0.703 ± 0.013 M⊙ and radii of R1 = 0.845 ± 0.012 R⊙ and R2

  4. Reagent Precoated Targets for Rapid In-Tissue Derivatization of the Anti-Tuberculosis Drug Isoniazid Followed by MALDI Imaging Mass Spectrometry

    Science.gov (United States)

    Manier, M. Lisa; Reyzer, Michelle L.; Goh, Anne; Dartois, Veronique; Via, Laura E.; Barry, Clifton E.; Caprioli, Richard M.

    2011-08-01

    Isoniazid (INH) is an important component of front-line anti-tuberculosis therapy with good serum pharmacokinetics but unknown ability to penetrate tuberculous lesions. However, endogenous background interferences hinder our ability to directly analyze INH in tissues. Chemical derivatization has been successfully used to measure isoniazid directly from tissue samples using matrix-assisted laser desorption/ionization (MALDI) imaging mass spectrometry (IMS). MALDI targets were pretreated with trans-cinnamaldehyde (CA) prior to mounting tissue slices. Isoniazid present in the tissues was efficiently derivatized and the INH-CA product measured by MS/MS. Precoating of MALDI targets allows the tissues to be directly thaw-mounted and derivatized, thus simplifying the preparation. A time-course series of tissues from tuberculosis infected/INH dosed animals were assayed and the MALDI MS/MS response correlates well with the amount of INH determined to be in the tissues by high-performance liquid chromatography (HPLC)-MS/MS.

  5. Early Holocene (8.6 ka) rock avalanche deposits, Obernberg valley (Eastern Alps): Landform interpretation and kinematics of rapid mass movement

    OpenAIRE

    Ostermann, Marc; Sanders, Diethard; Ivy-Ochs, Susan; Alfimov, Vasily; Rockenschaub, Manfred; Römer, Alexander

    2012-01-01

    In the Obernberg valley, the Eastern Alps, landforms recently interpreted as moraines are re-interpreted as rock avalanche deposits. The catastrophic slope failure involved an initial rock volume of about 45 million m³, with a runout of 7.2 km over a total vertical distance of 1330 m (fahrböschung 10°). 36Cl surface-exposure dating of boulders of the avalanche mass indicates an event age of 8.6 ± 0.6 ka. A 14C age of 7785 ± 190 cal yr BP of a palaeosoil within an alluvial fan downlapping the ...

  6. Rapid liquid chromatography/tandem mass spectrometer (LCMS) method for clozapine and its metabolite N-desmethyl clozapine (norclozapine) in human serum.

    Science.gov (United States)

    Rao, L V; Snyder, M L; Vallaro, G M

    2009-01-01

    Clozapine is indicated for the treatment of schizophrenia and related psychotic disorders. Several methods have been developed for monitoring Clozapine levels; however, they possess limited specificity and are often laborious. This study describes a simple liquid chromatography/tandem mass spectrometer (LCMS) method in human serum. The ion transitions monitored were m/z 327, 270, 296 for Clozapine, m/z 313, 192, 227 for Norclozapine and m/z 328, 271 for Loxapine. The assay is linear (25-1000 ng/ml) and showed a good correlation (r=0.98) within the analytical range of 79-1210 ng/ml in human serum. This assay is highly specific and sensitive for the simultaneous measurements of Clozapine and Norclozapine. The simplification of this assay makes it ideal for high throughput analyses of the patient samples in a routine clinical laboratory staffed with general medical technologists.

  7. Rapid screening and identification of multi-class substances of very high concern in textiles using liquid chromatography-hybrid linear ion trap orbitrap mass spectrometry.

    Science.gov (United States)

    Zhang, Li; Luo, Xin; Niu, Zengyuan; Ye, Xiwen; Tang, Zhixu; Yao, Peng

    2015-03-20

    A new analytical method was established and validated for the analysis of 19 substances of very high concern (SVHCs) in textiles, including phthalic acid esters (PAEs), organotins (OTs), perfluorochemicals (PFCs) and flame retardants (FRs). After ultrasonic extraction in methanol, the textile samples were analyzed by high performance liquid chromatography-hybrid linear ion trap Orbitrap high resolution mass spectrometry (HPLC-LTQ/Orbitrap). The values of LOQ were in the range of 2-200mg/kg. Recoveries at two levels (at the LOQ and at half the limit of regulation) ranged from 68% to 120%, and the repeatability was lower than 13%. This method was successfully applied to the screening of SVHCs in commercial textile samples and is useful for the fast screening of various SVHCs. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Stability evaluation and sensitive determination of antiviral drug, valacyclovir and its metabolite acyclovir in human plasma by a rapid liquid chromatography-tandem mass spectrometry method.

    Science.gov (United States)

    Yadav, Manish; Upadhyay, Vivek; Singhal, Puran; Goswami, Sailendra; Shrivastav, Pranav S

    2009-03-15

    A simple, sensitive and high throughput liquid chromatography/positive-ion electrospray ionization mass spectrometry (LC-ESI-MS/MS) method has been developed for the simultaneous determination of valacyclovir and acyclovir in human plasma using fluconazole as internal standard (IS). The method involved solid phase extraction of the analytes and IS from 0.5 mL human plasma with no reconstitution and drying steps (direct injection of eluate). The chromatographic separation was achieved on a Gemini C18 analytical column using isocratic mobile phase, consisting of 0.1% formic acid and methanol (30:70 v/v), at a flow-rate of 0.8 mL/min. The precursor-->product ion transition for valacyclovir (m/z 325.2-->152.2), acyclovir (m/z 226.2-->152.2) and IS (m/z 307.1-->220.3) were monitored on a triple quadrupole mass spectrometer, operating in the multiple reaction monitoring (MRM) mode. The method was validated over the concentration range 5.0-1075 ng/mL and 47.6-10225 ng/mL for valacyclovir and acyclovir respectively. The mean recovery of valacyclovir (92.2%), acyclovir (84.2%) and IS (103.7%) from spiked plasma samples was consistent and reproducible. The bench top stability of valacyclovir and acyclovir was extensively evaluated in buffered and unbuffered plasma. It was successfully applied to a bioequivalence study in 41 healthy human subjects after oral administration of 1000 mg valacyclovir tablet formulation under fasting condition.