Stepwise-external calibration has previously been shown to produce sub part-per-million (ppm) mass accuracy for the MALDI-FTICR/MS analyses of peptides up to m/z 2500. The present work extends these results to ions up to m/z 4000. Mass measurement errors for ions of higher mass-to-charge are larger than for ions below m/z 2500 when using conventional chirp excitation to detect ions. Mass accuracy obtained by using stored waveform inverse Fourier transform (SWIFT) excitation was evaluated and compared with chirp excitation. Analysis of measurement errors reveals that SWIFT excitation provides smaller deviations from the calibration equation and better mass accuracy than chirp excitation for a wide mass range and for widely varying ion populations.
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http://dx.doi.org/10.1016/j.jasms.2007.10.013 | DOI Listing |
Sci Rep
December 2024
Department of Chemistry, Illinois State University, Normal, IL, 61790-4160, USA.
This work aims to address key issues in the ballistic performance of ceramic-based composite armor, particularly at the joints of spliced bulletproof panels. The edge structure of C/C-SiC ceramic plates and ultra-high molecular weight polyethylene is redesigned to superimpose the joint areas. These structurally optimized composite pads are examined by numerical simulation of impact dynamics to understand their anti-penetration performance whose accuracy is then validated by live fire tests.
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December 2024
Laboratorio de Fluidodinámica, Facultad de Ingeniería, Universidad de Buenos Aires/CONICET, Paseo Colón 850 CABA, Buenos Aires, Argentina.
The oil and gas industry faces two significant challenges, including rising global temperatures and depletion of reserves. Enhanced recovery techniques such as polymer flooding have positioned themselves as an alternative that attracts international attention thanks to increased recovery factors with low emissions. However, existing physical models need further refinement to improve predictive accuracy and prevent design failures in polymer flooding projects.
View Article and Find Full Text PDFAdv Sci (Weinh)
December 2024
Department of Neurosurgery, Huashan Hospital of Fudan University, Shanghai, 200040, P. R. China.
Moyamoya disease (MMD) is a progressive cerebrovascular disorder that increases the risk of intracranial ischemia and hemorrhage. Timely diagnosis and intervention can significantly reduce the risk of new-onset stroke in patients with MMD. However, the current diagnostic methods are invasive and expensive, and non-invasive diagnosis using biomarkers of MMD is rarely reported.
View Article and Find Full Text PDFJ Sep Sci
January 2025
School of Pharmaceutical Sciences and Yunnan Provincial Key Laboratory of Pharmacology for Natural Medicines, Kunming Medical University, Kunming, Yunnan, People's Republic of China.
This study revealed the dynamic profiling of three main components of Portulaca oleracea L. in vivo in rats, namely allantoin (A), N-trans-feruloyl-3-methoxytyramine (M), and N-p-coumaroyltyramine (C). A sensitive and efficient UHPLC-ESI-Q-TOF/HRMS, including an optimized separation process, was applied to their qualitative and quantitative analysis.
View Article and Find Full Text PDFFront Oncol
December 2024
Department of Nuclear Medicine, Affiliated Hospital of Zunyi Medical University, Zunyi, China.
Hidradenocarcinoma (HAC) is a rare neoplasm that typically occurs in the head and neck region but seldom affects the chest wall. Histopathology and immunohistochemistry remain essential for diagnosing HAC, although their clinical utility in determining metastasis can be limited. Given the pathological rarity and histopathological heterogeneity of HAC, we report a case demonstrating the utility of positron emission tomography/computed tomography (PET/CT) combined with immunohistochemical examination for the accurate diagnosis and staging of HAC.
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