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The rotationally resolved ultraviolet absorption cross sections for the 2(0)(0)4(1)(0) vibrational band of the A(1)A(2)-X(1)A(1) electronic transition of formaldehyde (HCHO) at an apodized resolution of 0.027 cm(-1) (approximately 0.0003 nm at 352 nm) over the spectral range 28100-28500 cm(-1) (351-356 nm) at 298 and 220 K, using Fourier transform spectroscopy, are first reported here. Accurate rotationally resolved cross sections are important for the development of in situ HCHO laser-induced fluorescence (LIF) instruments and for atmospheric monitoring. Pressure dependence of the cross sections between 75 and 400 Torr at 298 K was explored, and an average pressure broadening coefficient in dry air of 1.8 x 10(-4) cm(-1) Torr(-1) for several isolated lines is reported. Gaseous HCHO was quantitatively introduced into a flow cell by evaporating micron-sized droplets of HCHO solution, using a novel microinjector technique. The condensed-phase concentrations of HCHO were determined by iodometric titrations to an accuracy of <1%. Accuracy of the measured absorption cross sections is estimated to be better than +/-5%. Integrated and differential cross sections over the entire band at low resolution (approximately 1 cm(-1)) obtained with our calibration technique are in excellent agreement with previous measurements. A maximum differential cross section of 5.7 x 10(-19) cm(2) molecule(-1) was observed at high resolution-almost an order of magnitude greater than any previously reported data at low resolution.
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http://dx.doi.org/10.1021/jp053466i | DOI Listing |
JMIR Serious Games
September 2025
Global Health Institute, American University of Beirut, PO Box 11-0236, Riad El Solh, Beirut, 1107 2020, Lebanon, 961 3047578.
Background: High maternal morbidity and mortality rates globally, especially in low-income and lower-middle-income countries, highlight the critical role of skilled health care providers (HCPs) in preventing pregnancy-related complications among disadvantaged populations. Lebanon, hosting over 1.5 million refugees, is no exception.
View Article and Find Full Text PDFPhys Rev Lett
August 2025
State Key Laboratory of Particle Detection and Electronics, Beijing 100049, Hefei 230026, People's Republic of China.
Using e^{+}e^{-} collision data collected with the BESIII detector operating at the Beijing electron positron collider, the cross section of e^{+}e^{-}→π^{+}π^{-}h_{c} is measured at 59 points with center-of-mass energy sqrt[s] ranging from 4.009 to 4.950 GeV with a total integrated luminosity of 22.
View Article and Find Full Text PDFJ Gerontol A Biol Sci Med Sci
September 2025
Department of Epidemiology and Biostatistics, College of Human Medicine, Michigan State University, East Lansing, MI.
Background: Poor olfaction may be associated with incident heart failure (HF) in older adults, but empirical evidence is scant.
Methods: We included 5,217 participants free of clinical HF and with a smell assessment in 2011-2013 from the Atherosclerosis Risk in Communities Study. Olfaction was measured by the 12-item Sniffin' Sticks odor identification test and defined as good (score 11-12), moderate (9-10), or poor (≤8).
PLOS Glob Public Health
September 2025
Section of General Internal Medicine, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, United States of America.
On January 26th 2024, the International Court of Justice (ICJ) recognized plausible grounds for genocide being committed in Gaza by Israel. A hallmark of the violence has been unprecedented attacks on health workers since October 7th, 2023. We use the word "genocide" to refer to this period of accelerated violence and displacement in Gaza, following ICJ findings, detailed reports by human rights organizations, and statements by genocide scholars concluding that Israel is indeed committing genocide.
View Article and Find Full Text PDFJAMA Cardiol
September 2025
Seymour, Paul and Gloria Milstein Division of Cardiology, Department of Medicine, Columbia University Irving Medical Center and New York-Presbyterian Hospital, New York, New York.
Importance: Transthyretin cardiac amyloidosis (ATTR-CA) is an underdiagnosed but treatable cause of heart failure (HF) in older individuals that occurs in the context of normal wild-type (ATTRwt-CA) or an abnormal inherited (ATTRv-CA) TTR gene variant. While the most common inherited TTR variant, V142I, occurs in 3% to 4% of self-identified Black Americans and is associated with excess morbidity and mortality, the prevalence of ATTR-CA in this at-risk population is unknown.
Objective: To define the prevalence of ATTR-CA and proportions attributable to ATTRwt-CA or ATTRv-CA among older Black and Caribbean Hispanic individuals with HF.