Relevant bibliographies by topics / 13C detection

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Academic literature on the topic '13C detection'

Author: Grafiati
Published: 10 March 2023

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Journal articles on the topic "13C detection"

1

Jacob, Arshia M., Karl M. Menten, Helmut Wiesemeyer, Rolf Güsten, Friedrich Wyrowski, and Bernd Klein. "First detection of 13CH in the interstellar medium." Astronomy & Astrophysics 640 (August 2020): A125. http://dx.doi.org/10.1051/0004-6361/201937385.

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In recent years, a plethora of observations with high spectral resolution of sub-millimetre and far-infrared transitions of methylidene (CH), conducted with Herschel and SOFIA, have demonstrated this radical to be a valuable proxy for molecular hydrogen that can be used for characterising molecular gas within the interstellar medium on a Galactic scale, including the CO-dark component. We report the discovery of the 13CH isotopologue in the interstellar medium using the upGREAT receiver on board SOFIA. We have detected the three hyperfine structure components of the ≈2 THz frequency transition from its X2Π1∕2 ground-state towards the high-mass star-forming regions Sgr B2(M), G34.26+0.15, W49(N), and W51E and determined 13CH column densities. The ubiquity of molecules containing carbon in the interstellar medium has turned the determination of the ratio between the abundances of the two stable isotopes of carbon, 12C/13C, into a cornerstone for Galactic chemical evolution studies. Whilst displaying a rising gradient with galactocentric distance, this ratio, when measured using observations of different molecules (CO, H2CO, and others), shows systematic variations depending on the tracer used. These observed inconsistencies may arise from optical depth effects, chemical fractionation, or isotope-selective photo-dissociation. Formed from C+ either through UV-driven or turbulence-driven chemistry, CH reflects the fractionation of C+, and does not show any significant fractionation effects, unlike other molecules that were previously used to determine the 12C/13C isotopic ratio. This makes it an ideal tracer for the 12C/13C ratio throughout the Galaxy. By comparing the derived column densities of 13CH with previously obtained SOFIA data of the corresponding transitions of the main isotopologue 12CH, we therefore derive 12C/13C isotopic ratios toward Sgr B2(M), G34.26+0.15, W49(N) and W51E. Adding our values derived from 12∕13CH to previous calculations of the Galactic isotopic gradient, we derive a revised value of 12C/13C = 5.87(0.45)RGC + 13.25(2.94).
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Okada, Yoko, Ronan Higgins, Volker Ossenkopf-Okada, Cristian Guevara, Jürgen Stutzki, and Marc Mertens. "First detection of [13C II] in the Large Magellanic Cloud." Astronomy & Astrophysics 631 (November 2019): L12. http://dx.doi.org/10.1051/0004-6361/201936685.

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Context. [13C II] observations in several Galactic sources show that the fine-structure [12C II] emission is often optically thick (the optical depths around 1 to a few). Aims. Our goal was to test whether this also affects the [12C II] emission from nearby galaxies like the Large Magellanic Cloud (LMC). Methods. We observed three star-forming regions in the LMC with upGREAT on board SOFIA at the frequency of the [C II] line. The 4 GHz bandwidth covers all three hyperfine lines of [13C II] simultaneously. For the analysis, we combined the [13C II] F = 1−0 and F = 1−1 hyperfine components as they do not overlap with the [12C II] line in velocity. Results. Three positions in N159 and N160 show an enhancement of [13C II] compared to the abundance-ratio-scaled [12C II] profile. This is likely due to the [12C II] line being optically thick, supported by the fact that the [13C II] line profile is narrower than [12C II], the enhancement varies with velocity, and the peak velocity of [13C II] matches the [O I] 63 μm self-absorption. The [12C II] line profile is broader than expected from a simple optical depth broadening of the [13C II] line, supporting the scenario of several PDR components in one beam having varying [12C II] optical depths. The derived [12C II] optical depth at three positions (beam size of 14″, corresponding to 3.4 pc) is 1−3, which is similar to values observed in several Galactic sources shown in previous studies. If this also applies to distant galaxies, the [C II] intensity will be underestimated by a factor of approximately 2.
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Bermel, Wolfgang, Isabella C. Felli, Rainer Kümmerle, and Roberta Pierattelli. "13C Direct-detection biomolecular NMR." Concepts in Magnetic Resonance Part A 32A, no. 3 (2008): 183–200. http://dx.doi.org/10.1002/cmr.a.20109.

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Hong, Donghyun, Yaewon Kim, Chandrasekhar Mushti, Noriaki Minami, Anne Marie Gillepspie, Georgios Batsios, Celine Taglang, et al. "TMET-16. DIRECT DETECTION OF 2HG AND GLUTAMATE PRODUCTION USING HYPERPOLARIZED [1-13C-5-12C]-Α-KETOGLUTARATE IN CELL AND IN VIVO GLIOMA MODELS." Neuro-Oncology 24, Supplement_7 (November 1, 2022): vii265. http://dx.doi.org/10.1093/neuonc/noac209.1021.

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Abstract Mutant IDH leads to 2HG production, which drives glioma development. 13C MRS monitoring of hyperpolarized [1-13C]α-ketoglutarate (αKG) metabolism to 2HG and glutamate provides a non-invasive assessment of the IDH mutation and normal metabolism, respectively. However, monitoring 2HG production in vivo has been challenging because its resonance is within 0.1 ppm of the natural abundance [5-13C]αKG signal of the [1-13C]αKG substrate. Here, we utilized [1-13C -5-12C]αKG, which eliminated the [5-13C]αKG peak. This new approach, combined with an optimized sequence, made it possible to readily monitor the production of both 2HG and glutamate in cells and in vivo in healthy rats or rats with orthotopic patient-derived glioma. Hyperpolarized [1-13C -5-12C]αKG was injected into genetically engineered NHAIDHmut cell lysates, healthy rats, and rats implanted orthotopically with BT257 cells intravenously. 1-D dynamic 13C MRS spectra from cells and in vivo slab spectroscopy data were then acquired using an 11.7 T NMR system and a 3 T pre-clinical scanner, respectively. Injection of the hyperpolarized [1-13C -5-12C]αKG into cell lysates showed clearly detectable dynamic conversion of hyperpolarized [1-13C-5-12C]αKG to 2HG and glutamate. The normal brain showed clear production of glutamate but no 2HG was detected. In tumor-bearing rats, we were able to clearly detect the dynamic production of both 2HG and glutamate. This study demonstrated the utility of hyperpolarized [1-13C-5-12C]αKG as a substrate to clearly assess 2HG production without the confounding presence of the natural abundance peak which cannot be distinguished from 2HG in vivo. Importantly, the detection of 2HG provides a clear indicator of the IDH mutation within the tumor.
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Lai, Marta, Bernard Lanz, Carole Poitry-Yamate, Jackeline F. Romero, Corina M. Berset, Cristina Cudalbu, and Rolf Gruetter. "In vivo 13C MRS in the mouse brain at 14.1 Tesla and metabolic flux quantification under infusion of [1,6-13C2]glucose." Journal of Cerebral Blood Flow & Metabolism 38, no. 10 (October 19, 2017): 1701–14. http://dx.doi.org/10.1177/0271678x17734101.

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In vivo 13C magnetic resonance spectroscopy (MRS) enables the investigation of cerebral metabolic compartmentation while, e.g. infusing 13C-labeled glucose. Metabolic flux analysis of 13C turnover previously yielded quantitative information of glutamate and glutamine metabolism in humans and rats, while the application to in vivo mouse brain remains exceedingly challenging. In the present study, 13C direct detection at 14.1 T provided highly resolved in vivo spectra of the mouse brain while infusing [1,6-13C2]glucose for up to 5 h. 13C incorporation to glutamate and glutamine C4, C3, and C2 and aspartate C3 were detected dynamically and fitted to a two-compartment model: flux estimation of neuron-glial metabolism included tricarboxylic acid cycle (TCA) flux in astrocytes (Vg = 0.16 ± 0.03 µmol/g/min) and neurons (VTCAn = 0.56 ± 0.03 µmol/g/min), pyruvate carboxylase activity (VPC = 0.041 ± 0.003 µmol/g/min) and neurotransmission rate (VNT = 0.084 ± 0.008 µmol/g/min), resulting in a cerebral metabolic rate of glucose (CMRglc) of 0.38 ± 0.02 µmol/g/min, in excellent agreement with that determined with concomitant 18F-fluorodeoxyglucose positron emission tomography (18FDG PET).We conclude that modeling of neuron-glial metabolism in vivo is accessible in the mouse brain from 13C direct detection with an unprecedented spatial resolution under [1,6-13C2]glucose infusion.
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Giesen, T. F., B. Mookerjea, G. W. Fuchs, A. A. Breier, D. Witsch, R. Simon, and J. Stutzki. "First detection of the carbon chain molecules 13CCC and C13CC towards SgrB2(M)." Astronomy & Astrophysics 633 (January 2020): A120. http://dx.doi.org/10.1051/0004-6361/201936538.

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Context. Carbon molecules and their 13C-isotopologues can be used to determine the 12C/13C abundance ratios in stellar and interstellar objects. C3 is a pure carbon chain molecule found in star-forming regions and in stellar shells of carbon-rich late-type stars. Latest laboratory data of 13C-isotopologues of C3 allow a selective search for the mono-substituted species 13CCC and C13CC based on accurate ro-vibrational frequencies. Aims. We aim to provide the first detection of the 13C-isotopologues 13CCC and C13CC in space and to derive the 12C/13C ratio of interstellar gas in the massive star-forming region SgrB2(M) near the Galactic Center. Methods. We used the heterodyne receivers GREAT and upGREAT on board SOFIA to search for the ro-vibrational transitions Q(2) and Q(4) of 13CCC and C13CC at 1.9 THz along the line of sight towards SgrB2(M). In addition, to determine the local excitation temperature, we analyzed data from nine ro-vibrational transitions of the main isotopologue CCC in the frequency range between 1.6 and 1.9 THz, which were taken from the Herschel Science Data Archive. Results. We report the first detection of the isotopologues 13CCC and C13CC. For both species, the ro-vibrational absorption lines Q(2) and Q(4) have been identified, primarily arising from the warm gas physically associated with the strong continuum source, SgrB2(M). From the available CCC ro-vibrational transitions, we derived a gas excitation temperature of Tex = 44.4+4.7−3.9 K, and a total column density of N(CCC) = 3.88+0.39−0.35 × 1015 cm−2. Assuming the excitation temperatures of C13CC and 13CCC to be the same as for CCC, we obtained column densities of the 13C-isotopologues of N(C13CC) = 2.1+0.9−0.6 × 1014 cm−2 and N(13CCC) = 2.4+1.2−0.8 × 1014 cm−2. The derived 12C/13C abundance ratio in the C3 molecules is 20.5 ± 4.2, which is in agreement with the elemental ratio of 20, typically observed in SgrB2(M). However, we find the N(13CCC)/N(C13CC) ratio to be 1.2 ± 0.1, which is shifted from the statistically expected value of two. We propose that the discrepant abundance ratio arises due to the lower zero-point energy of C13CC, which makes position-exchange reaction converting 13CCC to C13CC energetically favorable.
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Jeffries, Rex E., Shawn M. Gomez, Jeffrey M. Macdonald, and Michael P. Gamcsik. "Direct Detection of Glutathione Biosynthesis, Conjugation, Depletion and Recovery in Intact Hepatoma Cells." International Journal of Molecular Sciences 23, no. 9 (April 25, 2022): 4733. http://dx.doi.org/10.3390/ijms23094733.

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Nuclear magnetic resonance (NMR) spectroscopy was used to monitor glutathione metabolism in alginate-encapsulated JM-1 hepatoma cells perfused with growth media containing [3,3′-13C2]-cystine. After 20 h of perfusion with labeled medium, the 13C NMR spectrum is dominated by the signal from the 13C-labeled glutathione. Once 13C-labeled, the high intensity of the glutathione resonance allows the acquisition of subsequent spectra in 1.2 min intervals. At this temporal resolution, the detailed kinetics of glutathione metabolism can be monitored as the thiol alkylating agent monobromobimane (mBBr) is added to the perfusate. The addition of a bolus dose of mBBr results in rapid diminution of the resonance for 13C-labeled glutathione due to a loss of this metabolite through alkylation by mBBr. As the glutathione resonance decreases, a new resonance due to the production of intracellular glutathione-bimane conjugate is detectable. After clearance of the mBBr dose from the cells, intracellular glutathione repletion is then observed by a restoration of the 13C-glutathione signal along with wash-out of the conjugate. These data demonstrate that standard NMR techniques can directly monitor intracellular processes such as glutathione depletion with a time resolution of approximately < 2 min.
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Jeffries, Rex E., Shawn M. Gomez, Jeffrey M. Macdonald, and Michael P. Gamcsik. "Direct Detection of Glutathione Biosynthesis, Conjugation, Depletion and Recovery in Intact Hepatoma Cells." International Journal of Molecular Sciences 23, no. 9 (April 25, 2022): 4733. http://dx.doi.org/10.3390/ijms23094733.

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Nuclear magnetic resonance (NMR) spectroscopy was used to monitor glutathione metabolism in alginate-encapsulated JM-1 hepatoma cells perfused with growth media containing [3,3′-13C2]-cystine. After 20 h of perfusion with labeled medium, the 13C NMR spectrum is dominated by the signal from the 13C-labeled glutathione. Once 13C-labeled, the high intensity of the glutathione resonance allows the acquisition of subsequent spectra in 1.2 min intervals. At this temporal resolution, the detailed kinetics of glutathione metabolism can be monitored as the thiol alkylating agent monobromobimane (mBBr) is added to the perfusate. The addition of a bolus dose of mBBr results in rapid diminution of the resonance for 13C-labeled glutathione due to a loss of this metabolite through alkylation by mBBr. As the glutathione resonance decreases, a new resonance due to the production of intracellular glutathione-bimane conjugate is detectable. After clearance of the mBBr dose from the cells, intracellular glutathione repletion is then observed by a restoration of the 13C-glutathione signal along with wash-out of the conjugate. These data demonstrate that standard NMR techniques can directly monitor intracellular processes such as glutathione depletion with a time resolution of approximately < 2 min.
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Nercessian, Olivier, Emma Noyes, Marina G. Kalyuzhnaya, Mary E. Lidstrom, and Ludmila Chistoserdova. "Bacterial Populations Active in Metabolism of C1 Compounds in the Sediment of Lake Washington, a Freshwater Lake." Applied and Environmental Microbiology 71, no. 11 (November 2005): 6885–99. http://dx.doi.org/10.1128/aem.71.11.6885-6899.2005.

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ABSTRACT Active members of the bacterial community in the sediment of Lake Washington, with special emphasis on C1 utilizers, were identified by employing two complementary culture-independent approaches: reverse transcription of environmental mRNA and 16S rRNA combined with PCR (RT-PCR) and stable-isotope probing (SIP) of DNA with the 13C-labeled C1 substrates methanol, methylamine, formaldehyde, and formate. Analysis of RT-PCR-amplified fragments of 16S rRNA-encoding genes revealed that gammaproteobacterial methanotrophs belonging to Methylobacter and Methylomonas dominate the active methylotroph population, while only one other known methylotrophic lineage, Methylophilaceae, was detected via this approach. Analysis of RT-PCR-amplified functional genes, pmoA and fae, allowed detection of alphaproteobacterial (Methylosinus) and gammaproteobacterial (Methylobacter, Methylomonas, and Methylomicrobium) methanotrophs, methylotrophs of the genus Methylobacterium, and yet-unidentified proteobacteria. SIP experiments allowed detection of a broad variety of groups actively metabolizing C1 compounds. Comparisons between 16S rRNA gene pools amplified from [13C]DNA and from [12C]DNA revealed that the proportion of Methylophilus-related sequences increased in the presence of [13C]methanol, [13C]methylamine, and [13C]formaldehyde; Novosphingobium-related sequences were enriched in the presence of [13C]methanol; Gemmatimonadaceae-related sequences were enriched in the presence of [13C]formaldehyde and [13C]formate; and Xanthomonadaceae-related sequences were enriched in the presence of [13C]formate. Analysis of fae genes amplified from [13C]DNAs isolated from different microcosms revealed specific shifts in populations in response to a specific C1 compound: Methylosinus sequences dominated the [13C]methanol microcosm pool, and beta- and gammaproteobacterial sequences dominated the [13C]methylamine microcosm pool. The [13C]formaldehyde microcosm was dominated by betaproteobacterial sequences and by sequences of a nonaffiliated group, while the [13C]formate microcosm was dominated by alpha- and betaproteobacterial sequences. Overall, these data point toward the presence of a diverse population of active methylotrophs in Lake Washington sediments and toward the existence of yet-uncultivated organisms.
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Dénès, Fabrice, Julien Farard, and Jacques Lebreton. "Synthesis of 13C-Labeled Steroids." Synthesis 51, no. 23 (September 13, 2019): 4311–37. http://dx.doi.org/10.1055/s-0037-1611914.

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Due to the wide spectrum of biological activities of steroids, the detection and quantification of steroidal residues in various biological materials are crucial for drug development, doping prevention, and environmental protection. In addition, the analytical technique of stable isotopic dilution (SID) by Liquid Chromatography-Mass Spectrometry (LC-MS) requires 13C-labeled steroids as standards to provide accurate and reproducible steroid quantification. In this context, the synthesis of 13C-labeled steroids is reviewed. The approaches based on partial synthesis starting from commercially available steroids have been, by far, the most commonly employed strategy.1 Introduction2 Hemisynthesis of 13C3-Labeled Steroids via Partial Degradation of the A Ring2.1 Degradation of the A Ring to an Enol Lactone2.1.1 Introduction of 13C Atom(s) via Claisen Condensation: Turner’s Strategy2.1.2 Introduction of 13C Atom(s) with 13C-Labeled 5-(Diethylphosphono)pentan-2-one Ethylene Ketal Based on the Fujimoto–Belleau Reaction2.2 Degradation of the A Ring and Introduction of 13C Atom(s) with [13C3]-1-(Triphenylphosphoranylidene)propan-2-one3 Construction of the A Ring from an α,β-Unsaturated Ketone with 13C-Labeled 1-Iodo-3,3-(ethylenedioxy)butane as Electrophile4 Construction of the A and B rings: Stork’s Strategy5 Hemisynthesis with Introduction of 13C Atom(s) in the C17 Side Chain6 Conclusion
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Dissertations / Theses on the topic "13C detection"

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Day, S. E. "Detection of tumour treatment response using hyperpolarized 13C pyruvate." Thesis, University of Cambridge, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.598434.

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The exchange reaction between hyperpolarized 1-13C pyruvate and lactate, catalysed by the enzyme lactate dehydrogenase (LDH), can now be measured in real-time with 13C nuclear magnetic resonance spectroscopy and imaged in tissues using 13C MRI. EL-4 murine lymphoma cells catalyse this pyruvate-lactate exchange in a substrate-dependent fashion, and we demonstrate that the reaction is inhibited following treatment with chemotherapeutic drugs both in vitro and in vivo. The LDH reaction specifically labels the intratumoural lactate pool present within solid EL-4 murine lymphoma tumours, and this exchange was reduced following treatment with the chemotherapeutic drug etoposide. This novel metabolic imaging technique can be predictive of therapeutic success. The C6 intracranial rat glioma faithfully reproduces many morphological aspects of the human disease, and can be used as a model for the study of human brain tumours. When hyperpolarized pyruvate was administered to C6 glioma bearing rats, there was specific labelling of intratumoural lactate, and little to no polarized substrate in the normal brain. Following radiation therapy of these glioma bearing rats, the exchange of label between pyruvate and lactate was reduced as measured using chemical-shift imaging and was predictive of therapeutic success. Taken together, these results demonstrate the potential for hyperpolarized 13C pyruvate imaging to detect treatment response in vivo in different models of cancer. This work details initial studies into what might be a potentially valuable metabolic imaging tool. Hopefully this tool may one day be used by clinicians to improve the management of human cancer patients.
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Jordaan, Maraliese. "Diagnosis of helicobacter pylori infection with the 13C-urea breath test : analysis by means of gas chromatography with mass selective detection." Diss., University of Pretoria, 2007. http://hdl.handle.net/2263/27035.

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Gnanapandithan, Nithya. "Data detection and fusion in decentralized sensor networks." Thesis, Manhattan, Kan. : Kansas State University, 2005. http://hdl.handle.net/2097/132.

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Li, Zizheng. "Vertical Noise Structure and Target Detection Performance in Deep Ocean Environments." PDXScholar, 2010. https://pdxscholar.library.pdx.edu/open_access_etds/138.

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In passive sonar systems, knowledge of low-frequency shipping noise is an important factor for target detection performance. However, an accurate model for the shipping noise structure is difficult to obtain, due to the varying distributions of ships and complicated underwater environment. This work characterizes low-frequency distant shipping noise observed in deep water environments as a function of receiver depth and vertical arrival structure for the case of a receiver below the conjugate depth. Surface shipping noise is examined using Monte Carlo simulations using a normal mode propagation model based on random distribution of ships and realistic parameters. The depth dependence of the simulated distant shipping noise is in agreement with published experimental measurements. A Vertical Line Array (VLA) is used to produce vertical beams that isolate the surface interference from nearby targets. Simulation results quantifying the beamformer output as a function of ocean environment, receiver aperture, and frequency are presented for both conventional and adaptive beamformers. The results suggest that conventional beamforming could detect the noisy target from both direct arrival and bottom bounce in the presence of distant shipping interferers and wind noise. However, the beamwidth of conventional beamforming is wider than that of adaptive beamforming. Once the motion effects of nearby ship interferences are considered, the adaptive beamforming using diagonal loading provides better detection performance. Preliminary adaptive beamforming results corresponding to different snapshot times show that motion effects can be minimized by using short observation times.
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Demir, Sumeyra Ummuhan. "Image Processing Algorithms for Diagnostic Analysis of Microcirculation." VCU Scholars Compass, 2010. http://scholarscompass.vcu.edu/etd/137.

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Microcirculation has become a key factor for the study and assessment of tissue perfusion and oxygenation. Detection and assessment of the microvasculature using videomicroscopy from the oral mucosa provides a metric on the density of blood vessels in each single frame. Information pertaining to the density of these microvessels within a field of view can be used to quantitatively monitor and assess the changes occurring in tissue oxygenation and perfusion over time. Automated analysis of this information can be used for real-time diagnostic and therapeutic planning of a number of clinical applications including resuscitation. The objective of this study is to design an automated image processing system to segment microvessels, estimate the density of blood vessels in video recordings, and identify the distribution of blood flow. The proposed algorithm consists of two main stages: video processing and image segmentation. The first step of video processing is stabilization. In the video stabilization step, block matching is applied to the video frames. Similarity is measured by cross-correlation coefficients. The main technique used in the segmentation step is multi-thresholding and pixel verification based on calculated geometric and contrast parameters. Segmentation results and differences of video frames are then used to identify the capillaries with blood flow. After categorizing blood vessels as active or passive, according to the amount of blood flow, quantitative measures identifying microcirculation are calculated. The algorithm is applied to the videos obtained using Microscan Side-stream Dark Field (SDF) imaging technique captured from healthy and critically ill humans/animals. Segmentation results were compared and validated using a blind detailed inspection by experts who used a commercial semi-automated image analysis software program, AVA (Automated Vascular Analysis). The algorithm was found to extract approximately 97% of functionally active capillaries and blood vessels in every frame. The aim of this study is to eliminate the human interaction, increase accuracy and reduce the computation time. The proposed method is an entirely automated process that can perform stabilization, pre-processing, segmentation, and microvessel identification without human intervention. The method may allow for assessment of microcirculatory abnormalities occurring in critically ill and injured patients including close to real-time determination of the adequacy of resuscitation.
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Murino, Loredana. "Discovering hidden structures in high." Doctoral thesis, Universita degli studi di Salerno, 2011. http://hdl.handle.net/10556/137.

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2009 - 2010
Il grande volume di dati che viene attualmente collezionato nei vari campi di applicazione non può essere gestito usando le tecniche standard di data mining. L’obiettivo principale del presente lavoro di tesi è quello di trovare le soluzioni più ragionevoli per problemi di data mining legati alla gestione di dati ad alta dimensionalità. In particolare in questo lavoro di tesi sono stati considerate due applicazioni di data mining per dati multidimensionali. Il primo riguarda la cloud detection, ovvero un problema di classificazione di immagini multispettrali telerilevate da satellite, che dimostra l’alta affidabilità delle tecniche statistiche di analisi discriminante nel classificare questo tipo di immagini. Tali tecniche di classificazione sono state confrontate con tecniche standard basate su principi fisici per testare i costi di processo e il tasso pass/fail. La seconda applicazione riguarda la necessità di gestire dati multidimensionali per i quali è necessario fare assunzioni piuttosto che avere conferme (come nella precedente applicazione). Questo porta in modo naturale al problema del clustering di dati permettendo di trovare strutture significative all’interno degli stessi. Invece di scegliere l’una o l’altra tecnica di clustering, noi abbiamo scelto di approcciare il problema in modo più generale mediante il cosiddetto “consensus clustering”: piuttosto che cercare una singola soluzione al problema, l’obiettivo è trovare tutte le possibili soluzioni equivalentemente valide. A questo scopo è stata sviluppata una procedura automatica basata sul Least Squares Consensus Clustering. Le applicazioni sono state testate usando sia data-sets sintetici che reali,dimostrando la validità delle procedure. Grande enfasi è stata data anche alla validazione dei risultati attraverso l’uso di indicatori di performance per dimostrare l’affidabilità delle tecniche sviluppate. [edited by author]
IX n.s.
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Corcoran, Elaine M. "The trace detection of DNA adducts by accelerator mass spectrometry and 14C-postlabelling." Thesis, University of Leicester, 2004. http://hdl.handle.net/2381/30774.

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Accelerator mass spectrometry (AMS) is currently the most sensitive method for trace DNA adduct detection. O6-Mehtyldeoxyguanosine (O 6-MedG) is a strongly mutagenic lesion formed by a variety of alkylating agents. For this reason this was the adduct of choice for use in this study, the aim of which was to develop a 14C-postlabelling technique, involving incorporation of radiolabel onto O6-MedG adducts after isolation, thus enabling exploitation of AMS to detect low levels of adducts without the need to administer a 14C-labelled compound. A method was developed and optimised for acetylating O6-MedG, in < 90% yields. This method was then used to acetylate the adduct with 14C-acetic anhydride, but changes required for the safe handling of radiolabelled compound altered the reaction product profile, resulting in the major derivative being 14C-di-acetyl O6-MedG, (38% yield). This pure standard was used to determine detection limits of 1.4 pmoles of adduct using HPLC and liquid scintillation counting and 79 attomoles using AMS. A 3H-O6MedG standard was used to determine the efficiency of each stage of the 14C-postlabelling procedure. Overall assay efficiency was calculated to be 29% and taking this into account the practical limit of detection for the 14C-postlabelling procedure was calculated to be 272 attomoles of adduct. The assay was then utilised to quantitate O6-MedG adducts formed by exposure of DNA with MNU. The theoretical limit of detection was 3 adducts/1012 nucleosides, based on background 14C levels in blank HPLC fractions, which indicates the assay should ultimately be the most sensitive for detection of endogenous O6-MedG adducts in control human DNA. The techniques developed for this assay were utilised to quantitate O6-MedG adducts formed in DNA exposed to 14C-S-adenosylmethionine. Unfortunately no adducts were conclusively detected by AMS due to contamination of the samples, highlighting the problem of contamination in AMS analysis. However, with the addition of further purification steps, this assay could be sensitive enough to detect O6-MedG formed by the suspected endogenous carcinogen.
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Asami, Sam. "Method development for biomolecular solid-state NMR spectroscopy." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2014. http://dx.doi.org/10.18452/17044.

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Im Rahmen der vorliegenden Arbeit, wird ein neuartiges Markierungsschema für die Festkörper-NMR-Spektroskopie vorgestellt, das sogenannte Reduced Adjoining Protonation (RAP) Schema, welches die Protonendetektion sämtlicher Aliphaten erlaubt. Hochaufgelöste, 1H-detektierte 1H,13C Korrelationsspektren wurden erhalten. Des Weiteren wurde der Vorteil von hohen MAS-Frequenzen untersucht. 1H- und 13C-detektierte 3D Zuordnungsexperimente wurden implementiert, welche uns die Zuordnung von 90% aller aliphatischen Resonanzen von alpha-Spektrin SH3 erlaubten. Da die chemische Verschiebung abhängt vom Strukturmotiv, kann sie verwendet werden, um Sekundärstruktur-Informationen abzuleiten. Darüber hinaus wurde ein 1H-detektiertes H(H)CH 3D Experiment entwickelt, um weitreichende 1H,1H Kontakte zu ermitteln, welche für die Bestimmung der Tertiärstruktur genutzt werden können. Um artefaktfreie Relaxationsdaten zu erhalten, wurde das RAP-Markierungsschema modifiziert, um 1H- und 13C-verdünnte Proben zu erhalten, in denen Spindiffusion unterdrückt ist. Für die Untersuchung von Sub-Mikrosekunden-Dynamik werden Experimente vorgestellt zur Bestimmung von 13C T1 Relaxationszeiten und 1H,13C dipolaren Kopplungstensoren für Rückgrat- und Seitenketten-Resonanzen. Des weiteren zeigen wir, dass das RAP-Markierungsschema auf nicht-kristalline Systeme, wie Amyloidfibrillen des Abeta1-40 Peptids der Alzheimer-Krankheit, angewendet werden kann. Unter Verwendung von 1H-Detektion, erhielten wir hochaufgelöste 1H,13C Korrelationsspektren. Schließlich wurde der Perdeuterierungsansatz auf den L7Ae-box C/D Protein-RNA Komplex aus P. furiosus angewendet. Wir erhielten hochaufgelöste, 1H-detektierte 1H,15N, sowie 13C,13C Korrelationsspektren des Protein-RNA Komplexes. Weiterhin haben wir eine Methode zur Bestimmung genauer Abstands- und Winkelinformationen für die Protein-RNA Schnittstelle etabliert und schlagen Ansätze vor, für die Zuordnung der chemischen Verschiebungen von RNA-Resonanzen.
In this thesis, a novel labeling scheme for solid-state NMR spectroscopy, the Reduced Adjoining Protonation (RAP) scheme, is introduced, which allows proton detection of all aliphatic sites, as shown for the microcrystalline SH3 domain of alpha-spectrin. These samples yield high-resolution, 1H-detected 1H,13C correlation spectra. In addition, the benefit of high MAS frequencies was investigated. 1H- and 13C-detected 3D assignment experiments are implemented, which allowed us to assign 90% of all aliphatic resonances of alpha-spectrin SH3. As the chemical shift is dependent on the structural motif, it can be employed to derive secondary structure information. Furthermore, a 1H-detected H(H)CH 3D experiment is introduced, to obtain long-range 1H,1H contacts, which can be used for the determination of the tertiary structure. To obtain artifact-free relaxation data, the RAP labeling scheme was modified to obtain sparsely proton labeled, 13C dilute samples, in which spin diffusion is suppressed. To probe sub-microsecond dynamics, we report experiments to determine 13C T1 relaxation times and 1H,13C dipolar coupling tensors for backbone and side chain resonances, respectively. Furthermore, we show, that the RAP labeling scheme can be applied to non-crystalline systems, such as amyloid fibrils of the Alzheimer’s disease peptide Abeta1-40. Using 1H-detection, we obtained high-resolution 1H,13C correlation spectra. Finally, we applied the perdeuteration approach to the L7Ae-box C/D protein-RNA complex from P. furiosus. We obtained high-resolution, 1H-detected 1H,15N, as well as 13C,13C correlation spectra of the protein-RNA complex. In addition, we established a methodology to determine accurate distance and angular restraints for the protein-RNA interface and propose approaches for the chemical shift assignment of RNA resonances.
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Martel, Christopher. "Development of a Mass Detection Technique to Detect Intakes of Radioactive Material and their Resulting Radiation Exposures Following a Large-Scale Radiological Release." Digital WPI, 2019. https://digitalcommons.wpi.edu/etd-dissertations/520.

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Large-scale radiological accidents have resulted in intakes of radioactive materials by members of the public and occupational radiation workers. However, current methods to evaluate intakes are designed for small numbers of individuals and cannot be easily scaled for large populations as has occurred. A proposed method for high throughput volumes of people to identify and quantify intakes of radioactive material through urine radiobioassay is described. MATERIALS AND METHODS: The MCNP V6.0 software code was used to model the General Electric Hawkeye V3 Gamma Camera for gamma ray efficiency. Technitium-99m was used to validate the model. The model was used to calculate detection efficiencies and minimum detectable doses for Cobalt-60, Iodine-131, Cesium-137/Barium-137m and Iridium-192. RESULTS: Differences of 8% were observed between measurements of the detection efficiency for Technitium-99m and the MCNP modeled detection efficiency (11.1% vs. 12.0%, respectively). Calculations showed that a dose of 20 mSv could be detected using urine radiobioassay in 6, 3, 2, and 20 days post incident for Type F intakes of Cobalt-60, Iodine-131, Cesium-137/Barium-137m and Iridium-192 respectively. Approximately 1,152 urine samples could be analyzed in an eight-hour shift using a single gamma camera. CONCLUSIONS: The use of the gamma camera for urine radiobioassay allows for high throughput volumes of samples and has sufficient detection sensitivity to meet dose-based decision guidelines.
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LI, Haibing. "Financial fraud detection by using grammar-based multiobjective genetic programming with ensemble learning." Digital Commons @ Lingnan University, 2015. https://commons.ln.edu.hk/cds_etd/13.

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Financial fraud is a criminal act, which violates the law, rules or policy to gain unauthorized financial benefit. As an increasingly serious problem, it has attracted a lot of concerns. The major consequences are loss of billions of dollars each year, investor confidence and corporate reputation. Therefore, a study area called Financial Fraud Detection (FFD) is obligatory, in order to prevent the destructive results caused by financial fraud. In general, traditional modeling approaches are applied and based on pre-defined hypothesis testing of causes and effects for FFD problems. In addition, the evaluation criteria are often based on variable significance level or Goodness-of-fit only. FFD has many common features like other data mining problems. It has accumulated vast amounts of data records of different forms (e.g. financial statements or annual reports) over a period of time. It is very difficult to observe the interesting information just by relying on traditional statistical methods. However, data mining techniques can be used to extract implicit, previously unknown and potentially useful patterns, rules or relations from massive data repositories. Such discovered patterns are appropriate to executive leadership, stakeholders and related regulatory agencies to reduce or avoid the losses. As real-life problems, it is not sufficient for FFD to consider only a single criterion (e.g. Goodness-of-fit or accuracy). Instead, FFD can also seek multiple objectives (e.g. accuracy versus interestingness). It is not easy to consider multiple objectives at the same time unless applying combination methods (e.g. linear combination) by assigning different weights to present the importance for each criterion by using data mining techniques with a single evaluation criterion. For example, accuracy is more important than interestingness with weights of 0.9:0.1. But it is still difficult to decide the appropriate or exact values for weights. There-fore, multi-objective data-mining techniques are required to tackle FFD problems. In this study, FFD is targeted, and comprehensively evaluated by a number of methods. The proposed method is based on Grammar-Based Genetic Programming (GBGP), which has been proven to be a powerful data mining technique to generate compact and straightforward results. The major contributions are three improvements of GBGP for FFD problems. First, multi-criteria are considered by integrating the concept of multi-objectives into GBGP. Second, minority prediction is applied to demonstrate the class prediction with unmatched rows in their rules. Lastly, a new meta-heuristic approach is introduced for ensemble learning in order to help users to select patterns from a pool of models to facilitate final decision-making. The experimental results showed the effectiveness of the new approach in four FFD problems including two real-life problems. The major implications and significances of the study can concretely generalize for three points. First, it suggests a new ensemble learning technique with GBGP. Second, it demonstrates the usability of classification rules generated by the proposed method. Third, it provides an efficient multi-objective method for solving FFD problems.
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Books on the topic "13C detection"

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Kim, Kwangjo, Muhamad Erza Aminanto, and Harry Chandra Tanuwidjaja. Network Intrusion Detection using Deep Learning. Singapore: Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-13-1444-5.

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Liu, Leibo, Guiqiang Peng, and Shaojun Wei. Massive MIMO Detection Algorithm and VLSI Architecture. Singapore: Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-13-6362-7.

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Peng, Rui, Yan-Fu Li, and Yu Liu. Software Fault Detection and Correction: Modeling and Applications. Singapore: Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-13-1162-8.

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Mannion, Elizabeth, ed. The Contemporary Irish Detective Novel. London: Palgrave Macmillan UK, 2016. http://dx.doi.org/10.1057/978-1-137-53940-3.

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Clarke, Clare. British Detective Fiction 1891–1901. London: Palgrave Macmillan UK, 2020. http://dx.doi.org/10.1057/978-1-137-59563-8.

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Dixon, Franklin W. Maximum Challenge: Hardy Boys #132. New York: Pocket Books, 1995.

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Yan Shan, Ang. Engineering a Robust DNA Circuit for the Direct Detection of Biomolecular Interactions. Singapore: Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-13-2188-7.

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Malet, Léo. Brouillard au pont de Tolbiac: Les nouveaux mystères de Paris, 13e arrondissement. Paris: Presses de la Cité, 1989.

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130 años de Martí en Guatemala. Guatemala: Armar Editores, 2009.

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Okomeni︠u︡k, Tatʹi︠a︡na. Taĭny i prikli︠u︡chenii︠a︡: Sbornik detektivnykh i prikli︠u︡chencheskikh rasskazov : k 130-letii︠u︡ Agaty Kristi. Volgograd: Izdatelʹstvo "Periskop-Volga", 2020.

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Book chapters on the topic "13C detection"

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Felli, Isabella C., and Roberta Pierattelli. "13C Direct Detection NMR." In NMR of Biomolecules, 432–43. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2012. http://dx.doi.org/10.1002/9783527644506.ch26.

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de Graaf, Robin. "Techniques-MRS, fMRI, 13C NMR, Indirect Detection of 13C." In Brain Energetics and Neuronal Activity, 31–52. Chichester, UK: John Wiley & Sons, Ltd, 2005. http://dx.doi.org/10.1002/0470020520.ch3.

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Hanashima, Shinya, and Yoshiki Yamaguchi. "Indirect Detection of Hydroxy Proton Exchange Through Deuterium-Induced 13C-NMR 13C-NMR Isotope shift Isotope Shifts." In Glycoscience: Biology and Medicine, 129–35. Tokyo: Springer Japan, 2014. http://dx.doi.org/10.1007/978-4-431-54841-6_100.

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Larkey, Nicholas E., Erica M. Fatica, and Ravinder J. Singh. "Detection of 13C-Mannitol and Other Saccharides Using Tandem Mass Spectrometry for Evaluation of Intestinal Permeability or Leaky Gut." In Clinical Applications of Mass Spectrometry in Biomolecular Analysis, 285–94. New York, NY: Springer US, 2022. http://dx.doi.org/10.1007/978-1-0716-2565-1_26.

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Genzel, R., A. Poglitsch, and G. Stacey. "Detection of Far-Infrared 13CO Line Emission." In Submillimetre Astronomy, 261–62. Dordrecht: Springer Netherlands, 1990. http://dx.doi.org/10.1007/978-94-015-6850-0_99.

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Franchak, John M. "Looking with the Head and Eyes." In Perception as Information Detection, 205–21. New York, NY : Routledge, 2020. | Series: Resources for ecological psychology: Routledge, 2019. http://dx.doi.org/10.4324/9780429316128-13.

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Farrar, J. K. "The Detection of Cerebral Ischemia Using Xenon 133." In Cerebral Blood Flow and Metabolism Measurement, 113–17. Berlin, Heidelberg: Springer Berlin Heidelberg, 1985. http://dx.doi.org/10.1007/978-3-642-70054-5_16.

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Knight, Stephen. "Beginning Detection." In Crime Fiction since 1800, 3–29. London: Macmillan Education UK, 2010. http://dx.doi.org/10.1007/978-1-137-02021-5_1.

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Knight, Stephen. "Developing Detection." In Crime Fiction since 1800, 30–63. London: Macmillan Education UK, 2010. http://dx.doi.org/10.1007/978-1-137-02021-5_2.

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Kinser, Jason M. "Edge Detection." In Image Operators, 189–98. First edition. | Boca Raton, FL: CRC Press/Taylor & Francis Group, [2019] |: CRC Press, 2018. http://dx.doi.org/10.1201/9780429451188-13.

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Conference papers on the topic "13C detection"

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RUEGG, R., B. F. MILTON, D. DALE, D. BISHOP, B. ROBERTS, P. W. SCHMOR, J. SREDNIAWSKI, S. MELNYCHUK, J. RATHKE, and E. KAMYKOWSKI. "Contraband Detection based on 13C(p,γ)14N." In Proceedings of the 3rd International Conference on Isotopes. WORLD SCIENTIFIC, 2000. http://dx.doi.org/10.1142/9789812793867_0110.

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Margulès, L., Arnaud Belloche, Holger Müller, J. C. Guillemin, and R. Motiyenko. "FIRST SPECTROSCOPIC STUDIES AND DETECTION IN SgrB2 OF 13C-DOUBLY SUBSTITUED ETHYL CYANIDE." In 70th International Symposium on Molecular Spectroscopy. Urbana, Illinois: University of Illinois at Urbana-Champaign, 2015. http://dx.doi.org/10.15278/isms.2015.ri06.

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Thind, Kundan, Lanette Friesen-Waldner, Albert Chen, Alexei Ouriadov, Tim Scholl, Matthew Fox, Eugene Wong, et al. "Detection Of Radiation Induced Lung Injury Using Hyperpolarized 13C Magnetic Resonance Spectroscopy And Imaging." In American Thoracic Society 2012 International Conference, May 18-23, 2012 • San Francisco, California. American Thoracic Society, 2012. http://dx.doi.org/10.1164/ajrccm-conference.2012.185.1_meetingabstracts.a5582.

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Zhevlakov, Aleksandr, Alexsandr S. Grishkanich, Yan Chubchenko, Leonid Konopelko, and Valentin Elizarov. "SRS-sensor 13C/12C isotops measurements for detecting Helicobacter Pylori." In Optical Fibers and Sensors for Medical Diagnostics and Treatment Applications XVIII, edited by Israel Gannot. SPIE, 2018. http://dx.doi.org/10.1117/12.2295927.

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Kawai, Tatsuya, Murali C. Krishna, Tamalee Kramp, Jeffery R. Brender, Philip Tofilon, and Kevin A. Camphausen. "Abstract 1944: Detection of metabolic change in glioblastoma after radiotherapy using hyperpolarized 13C-MRI: Glycolytic metabolism in cancer stem cell-like cell-derived tumor model." In Proceedings: AACR Annual Meeting 2019; March 29-April 3, 2019; Atlanta, GA. American Association for Cancer Research, 2019. http://dx.doi.org/10.1158/1538-7445.sabcs18-1944.

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Kawai, Tatsuya, Murali C. Krishna, Tamalee Kramp, Jeffery R. Brender, Philip Tofilon, and Kevin A. Camphausen. "Abstract 1944: Detection of metabolic change in glioblastoma after radiotherapy using hyperpolarized 13C-MRI: Glycolytic metabolism in cancer stem cell-like cell-derived tumor model." In Proceedings: AACR Annual Meeting 2019; March 29-April 3, 2019; Atlanta, GA. American Association for Cancer Research, 2019. http://dx.doi.org/10.1158/1538-7445.am2019-1944.

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Luo, Pan, Jonathan Harrist, Rabah Mesdour, and Nathan Stmichel. "Moving Gas Geochemical Analysis from Lab to Field by Advanced Gas Sensor for Onsite Fluid Characterization and Time-Lapse Monitoring." In SPE Middle East Oil & Gas Show and Conference. SPE, 2021. http://dx.doi.org/10.2118/204775-ms.

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Abstract Natural gas is sampled or produced throughout the lifespan of a field, including geochemical surface survey, mud gas logging, formation and well testing, and production. Detecting and measuring gas is a common practice in many upstream operations, providing gas composition and isotope data for multiple purposes, such as gas show, petroleum system analysis, fluid characterization, and production monitoring. Onsite gas analysis is usually conducted within a mud gas unit, which is operationally unavailable after drilling. Gas samples need be taken from the field and shipped back to laboratory for gas chromatography and isotope-ratio mass spectrometry analyses. Results take a considerable time and lack the resolution needed to fully characterize the heterogeneity and dynamics of fluids within the reservoir. We are developing and testing advanced sensing technology to move gas composition and isotope analyses to field for near real-time and onsite fluid characterization and monitoring. We have developed a novel QEPAS (quartz-enhanced photoacoustic spectroscopy) sensor system, employing a single interband cascade laser, to measure concentrations of methane (C1), ethane (C2), and propane (C3) in gas phase. The quartz fork detection module, laser driver, and interface are integrated as a small sensing box. The sensor, sample preparation enclosures and a computer are mounted in a rack as a gas analyzer prototype for the bench testing for oil industry application. Software is designed for monitoring sample preparation, collecting data, calibration and continuous reporting sample pressure and concentration data. The sensor achieved an ultimate detection limit of 90 ppb (parts per billion), 7 ppb and 3 ppm (parts per million) for C1, C2, and C3, respectively, for one second integration time. The detection limit for C2 made a record for QEPAS technique, and measuring C3 added a new capability to the technique. However, the linearity of the QEPAS sensing were previously reported in the range of 0 to 1000 ppm, which is mainly for trace gas detection. In the study, the prototype was separately tested on standard C1, C2, and C3 with different concentrations diluted in dry nitrogen (N2). Good linearity was obtained for all single components and the ranges of linearity were expanded to their typical concentrations (per cent, %) in natural gas samples from oil and gas fields. The testing on the C1-C2 mixtures confirms that accurate C1 and C2 concentrations in % level can be achieved by the prototype. The testing results on C1-C2-C3 mixtures demonstrate the capability of simultaneous detection of three hydrocarbon components and the probability to determine their precise concentrations by QEPAS sensing. This advancement of simultaneous measuring C1, C2 and C3 concentrations, with previously demonstrated capability for hydrogen sulfide (H2S) and carbon dioxide (CO2) and potential to analyze carbon isotopes (13C/12C), promotes QEPAS as a prominent optical technology for gas detection and chemical analysis. The capability of measuring multiple gas components and the advantages in small sensor size, high sensitivity, quick analysis, and continuous sensing (monitoring) open the way to use QEPAS technique for in-situ and real-time gas sensing in oil industry. The iterations of QEPAS sensor might be applied in geochemical survey, on-site fluid characterization, time-lapse monitoring of production, and gas linkage detection in the oil industry.
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Ryzhkov, V. A., and I. N. Pyatkov. "Prompt γ and neutron spectrometry of intense nanosecond ion bunches collectively accelerated in a Luce diode." In 8th International Congress on Energy Fluxes and Radiation Effects. Crossref, 2022. http://dx.doi.org/10.56761/efre2022.s1-p-041101.

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Instantaneous time-of-flight spectrometry of neutrons (nToF) and γ‑spectrometry from nuclear reactions generated by nanosecond proton and 12C ion bunches collectively accelerated in a Luce diode at a voltage across the diode of 200–300 kV has been thoroughly researched. A two-channel γ‑spectrometer with time resolution of 2.5 ns enables a prompt control of number and energy of collectively accelerated protons in their separate bunches dumped into a sustainable and refractory B4C target. Combination of nuclear reactions 10B(p,αγ)7Be, 12C(p,γ)13N, and 11B(p,γ)12C was used to characterize the intense nanosecond proton bunches with energy and number per shot in excess of 500–750 keV and 6∙1014, respectively. The radioactivity of 7Be and 13N radionuclides was measured with a conventional HP Ge detector to calibrate the prompt technique. The threshold nuclear reaction 11B(p,n)11C was used to perform nToF spectrometry of high-energy protons bunches with energy higher than 3.02 MeV, while 12C(d,n)13N and 2H(12C,n)13N reactions were used to control deuteron and 12C ion bunches.
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Канаева, Ирина, Irina Kanaeva, Юлия Иванова, and Yuliya Ivanova. "Instance Segmentation of Road Pavement Cracks." In 29th International Conference on Computer Graphics, Image Processing and Computer Vision, Visualization Systems and the Virtual Environment GraphiCon'2019. Bryansk State Technical University, 2019. http://dx.doi.org/10.30987/graphicon-2019-1-131-135.

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Robust automatic pavement crack detection is critical to automated road condition evaluation. Manual crack detection is extremely time-consuming. Therefore, an automatic road crack detection method is required to boost this progress. This study makes literature review of road damage detection issues. The paper considers the existing datasets for detection and segmentation distress of road and asphalt pavement. A CNN for pavement cracks instance segmentation has been developed with the use of images from the driver's seat view. A method for generating a synthetic dataset is also presented, and effectiveness of its applicability to the current problem is evaluated. The relevance of the study is emphasized by research on pixel-level automatic damage detection remains a challenging problem, due to heterogeneous pixel intensity, complex crack topology, poor illumination condition, and noisy texture background.
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Wang, Jiajie, Jiangchao Yao, Ya Zhang, and Rui Zhang. "Collaborative Learning for Weakly Supervised Object Detection." In Twenty-Seventh International Joint Conference on Artificial Intelligence {IJCAI-18}. California: International Joint Conferences on Artificial Intelligence Organization, 2018. http://dx.doi.org/10.24963/ijcai.2018/135.

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Weakly supervised object detection has recently received much attention, since it only requires image-level labels instead of the bounding-box labels consumed in strongly supervised learning. Nevertheless, the save in labeling expense is usually at the cost of model accuracy.In this paper, we propose a simple but effective weakly supervised collaborative learning framework to resolve this problem, which trains a weakly supervised learner and a strongly supervised learner jointly by enforcing partial feature sharing and prediction consistency. For object detection, taking WSDDN-like architecture as weakly supervised detector sub-network and Faster-RCNN-like architecture as strongly supervised detector sub-network, we propose an end-to-end Weakly Supervised Collaborative Detection Network. As there is no strong supervision available to train the Faster-RCNN-like sub-network, a new prediction consistency loss is defined to enforce consistency of predictions between the two sub-networks as well as within the Faster-RCNN-like sub-networks. At the same time, the two detectors are designed to partially share features to further guarantee the model consistency at perceptual level. Extensive experiments on PASCAL VOC 2007 and 2012 data sets have demonstrated the effectiveness of the proposed framework.
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Reports on the topic "13C detection"

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Ames A. Grisanti and Charlene R. Crocker. EM Task 13 - Cone Penetrometer for Subsurface Heavy Metals Detection. Office of Scientific and Technical Information (OSTI), November 1998. http://dx.doi.org/10.2172/3838.

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Stromer, Bobbi, Anthony Bednar, Milo Janjic, Scott Becker, Tamara Kylloe, John Allen, Matt Trapani, John Hargrove, and James Hargrove. Trace explosives detection by cavity ring-down spectroscopy (CRDS). Engineer Research and Development Center (U.S.), August 2021. http://dx.doi.org/10.21079/11681/41520.

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We built three successive versions of a thermal decomposition cavity ring-down spectrometer and tested their response to explosives. These explosive compound analyzers successfully detected nitroglycerine, 2,4,6-trinitrotoluene (TNT), pentaerythryl tetranitrate, hexahydro-1,3,5-trinitro-s-triazine and triacetone triperoxide (TATP). We determined the pathlength and limits of detection for each, with the best limit of detection being 13 parts per trillion (ppt) of TNT. For most of the explosive tests, the peak height was higher than the expected value, meaning that peroxy radical chain propagation was occurring with each of the explosives and not just the peroxide TATP.
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Grisanti, A. A., R. C. Timpe, H. J. Foster, K. E. Eylands, and C. R. Crocker. EM Task 13 -- Cone penetrometer for subsurface heavy metals detection. Semi-annual report, April 1--September 30, 1997. Office of Scientific and Technical Information (OSTI), December 1997. http://dx.doi.org/10.2172/666008.

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Camell, D. G., Seturnino Canales, Galen H. Koepke, Kate A. Remley, Susan A. Schima, Douglas T. Tamaura, Dylan Forrest Williams, and Christopher L. Holloway. Propagation and detection of radio signals before, during, and after the implosion of a 13-story apartment building. Gaithersburg, MD: National Bureau of Standards, 2005. http://dx.doi.org/10.6028/nist.tn.1540.

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Kamrath, Matthew, Vladimir Ostashev, D. Wilson, Michael White, Carl Hart, and Anthony Finn. Vertical and slanted sound propagation in the near-ground atmosphere : amplitude and phase fluctuations. Engineer Research and Development Center (U.S.), May 2021. http://dx.doi.org/10.21079/11681/40680.

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Sound propagation along vertical and slanted paths through the near-ground atmosphere impacts detection and localization of low-altitude sound sources, such as small unmanned aerial vehicles, from ground-based microphone arrays. This article experimentally investigates the amplitude and phase fluctuations of acoustic signals propagating along such paths. The experiment involved nine microphones on three horizontal booms mounted at different heights to a 135-m meteorological tower at the National Wind Technology Center (Boulder, CO). A ground-based loudspeaker was placed at the base of the tower for vertical propagation or 56m from the base of the tower for slanted propagation. Phasor scatterplots qualitatively characterize the amplitude and phase fluctuations of the received signals during different meteorological regimes. The measurements are also compared to a theory describing the log-amplitude and phase variances based on the spectrum of shear and buoyancy driven turbulence near the ground. Generally, the theory correctly predicts the measured log-amplitude variances, which are affected primarily by small-scale, isotropic turbulent eddies. However, the theory overpredicts the measured phase variances, which are affected primarily by large-scale, anisotropic, buoyantly driven eddies. Ground blocking of these large eddies likely explains the overprediction.
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Islam, Wasikul. Performance of b Jet Identification at $\sqrt{s}$ = 13 TeV with the ATLAS Detector at CERN. Office of Scientific and Technical Information (OSTI), June 2018. http://dx.doi.org/10.2172/1462088.

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Leonard, Talayna, Robert Lemme, Cati Kral, Briana Santiago, Chris Elberts, Stephanie Dewald, Patrick McGonagill, et al. High-Percentage of Early Resectable Pancreatic Ductal Adenocarcinoma is Unidentified on Abdominal CT Obtained for Unrelated Diagnosis. Science Repository, December 2021. http://dx.doi.org/10.31487/j.aco.2021.02.03.

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Objective: Pancreatic ductal adenocarcinoma (PDAC) has the best survival when detected early with 5-year survival near 40% for small, resectable PDAC. We evaluate the undiagnosed PDAC imaging features on routine CT and their impact on resectability. Methods: 76 of the screened 134 CTs from 1/1/2012 to 12/31/2018 using our tumor registry were obtained prior to PDAC diagnosis for other indications at least one month before presentation. Each cross-sectional study was reviewed for features of early PDAC: pancreatic mass, pancreatic ductal dilatation, perivascular/peripancreatic soft-tissue infiltration, omental lesions/ascites, and lymphadenopathy. When such features were detectible by the reviewing radiologists, the original CT readings were classified as concordant/discrepant. Descriptive statistics are reported for discrepant reads, tumor resectability, and tumor size. Results: Of the 76 cases from 46 unique subjects (30 male/16 female), 25 CTs (33%) had undetected PDAC imaging features: masses (15/19 unreported), ductal dilatation (16/20 unreported), and peripancreatic/perivascular soft-tissue infiltration (20/36 unreported). 63% of early PDAC features were not identified initially. One year before clinical diagnosis, 75-80% of the PDAC cases were resectable; at < 6 months before clinical diagnosis, only 29% were resectable. Conclusion: Improving early detection of key PDAC features on routine CT examinations can potentially improve patient outcomes.
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8

Duarte, Javier Mauricio. Naturalness confronts nature: searches for supersymmetry with the CMS detector in pp collisions at √s = 8 and $13$ TeV. Office of Scientific and Technical Information (OSTI), January 2017. http://dx.doi.org/10.2172/1342209.

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9

Young, Craig. Problematic plant monitoring in Pea Ridge National Military Park: 2006–2021. Edited by Tani Hubbard. National Park Service, June 2022. http://dx.doi.org/10.36967/nrr-2293656.

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Managers are challenged with the impact of problematic plants, including exotic, invasive, and pest plant species. Information on the cover and frequency of these plant species is essential for developing risk-based approaches to managing them. Based on surveys conducted in 2006, 2013, 2018, and 2021, Heartland Inventory and Monitoring Network staff and contractors identified a cumulative total of 38 potentially problematic plant species in Pea Ridge National Military Park. Of the 35 species found in 2021, we characterized 13 as very low frequency, 9 as low frequency, 9 as medium frequency, and 4 as high frequency. Of these 35 species, midpoint cover estimates of 4 medium frequency and all 4 high frequency species exceeded the 10-acre threshold. The 10-acre threshold represents a limit beyond which eradication of a problematic plant species is likely not possible. Clearing of eastern redcedar (Juniperus virginiana) continues to be evident in our observations, and sericea lespedeza (Lespedeza cuneata) appears to have increased as clearing progressed. The rapid increase in Japanese stiltgrass (Microstegium vimineum) appears to be parkwide. Because of the number, extent, and cover of problematic plants in the park, control efforts should focus on early detection treatments and strategic treatment of high priority, widespread species to protect features of the park’s natural and cultural landscapes. High priority species may include plant species capable of rapid spread, species at low population levels, and species that can be effectively controlled.
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Sterenberg Frankenthal, Andre. Search for dark matter decaying to two displaced muons produced in proton-proton collisions at 13 TeV with the CMS detector, and for dark photons produced in electron-positron fixed-target collisions at 500 MeV with the PADME detector. Office of Scientific and Technical Information (OSTI), January 2020. http://dx.doi.org/10.2172/1774288.

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