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Isoprene-derived secondary organic aerosol (iSOA) is a significant contributor to organic carbon (OC) in some forested regions, such as tropical rainforests and the Southeastern US. However, its contribution to organic aerosol in urban areas that have high levels of anthropogenic pollutants is poorly understood. In this study, we examined the formation of anthropogenically influenced iSOA during summer in Beijing, China. Local isoprene emissions and high levels of anthropogenic pollutants, in particular NOx and particulate SO42-, led to the formation of iSOA under both high- and low-NO oxidation conditions, with significant heterogeneous transformations of isoprene-derived oxidation products to particulate organosulfates (OSs) and nitrooxy-organosulfates (NOSs). Ultra-high-performance liquid chromatography coupled to high-resolution mass spectrometry was combined with a rapid automated data processing technique to quantify 31 proposed iSOA tracers in offline PM2.5 filter extracts. The co-elution of the inorganic ions in the extracts caused matrix effects that impacted two authentic standards differently. The average concentration of iSOA OSs and NOSs was 82.5 ng m−3, which was around 3 times higher than the observed concentrations of their oxygenated precursors (2-methyltetrols and 2-methylglyceric acid). OS formation was dependant on both photochemistry and the sulfate available for reactive uptake, as shown by a strong correlation with the product of ozone (O3) and particulate sulfate (SO42-). A greater proportion of high-NO OS products were observed in Beijing compared with previous studies in less polluted environments. The iSOA-derived OSs and NOSs represented 0.62 % of the oxidized organic aerosol measured by aerosol mass spectrometry on average, but this increased to ∼3 % on certain days. These results indicate for the first time that iSOA formation in urban Beijing is strongly controlled by anthropogenic emissions and results in extensive conversion to OS products from heterogenous reactions.

Nitrous acid (HONO) is a key determinant of the daytime radical budget in the daytime boundary layer, with quantitative measurement required to understand OH radical abundance. Accurate and precise measurements of HONO are therefore needed; however HONO is a challenging compound to measure in the field, in particular in a chemically complex and highly polluted environment. Here we report an intercomparison exercise between HONO measurements performed by two wet chemical techniques (the commercially available a long-path absorption photometer (LOPAP) and a custom-built instrument) and two broadband cavity-enhanced absorption spectrophotometer (BBCEAS) instruments at an urban location in Beijing. In addition, we report a comparison of HONO measurements performed by a time-of-flight chemical ionization mass spectrometer (ToF-CIMS) and a selected ion flow tube mass spectrometer (SIFT-MS) to the more established techniques (wet chemical and BBCEAS). The key finding from the current work was that all instruments agree on the temporal trends and variability in HONO (r2 > 0.97), yet they displayed some divergence in absolute concentrations, with the wet chemical methods consistently higher overall than the BBCEAS systems by between 12 % and 39 %. We found no evidence for any systematic bias in any of the instruments, with the exception of measurements near instrument detection limits. The causes of the divergence in absolute HONO concentrations were unclear, and may in part have been due to spatial variability, i.e. differences in instrument location and/or inlet position, but this observation may have been more associative than casual.

The parameters defining vulnerability in graph theory can be used as an indicator of the service quality over the network, if nodes or links fail. In the field of graph theory, numerous vulnerability parameters have been defined, including toughness, rupture degree, tenacity, integrity, connectivity, and others. Fuzzy graphs, a specific type of graphs, provide a more effective method of modelling real-world problems than other graphs. This is due to the fact that the uncertainties inherent in the problems can be expressed in a more realistic manner through the use of membership values. However, despite this advantage, there has been limited research conducted on the vulnerability parameters in fuzzy graphs. In this paper, the node connectivity parameter for fuzzy wheel graphs, fuzzy cycle graphs, and fuzzy star graphs are researched and some general formulas are obtained. Additionally, the algorithms are given to find the strength of connectedness between any two nodes and the node connectivity of the given fuzzy graph. [ABSTRACT FROM AUTHOR]

Objectives: Characterize the presentation of patients with non‐angiotensin‐converting enzyme inhibitor (ACEI)‐induced angioedema and determine risk factors associated with patient disposition and possible need for airway intervention. Methods: The medical records of adult patients in the Emergency Department (ED) and diagnosed with non‐ACEI‐induced angioedema over 4.5 years were included. Demographics, vital signs, etiology, timeline, presenting symptoms, physical exam including flexible laryngoscopy, medical management, and disposition were examined. Statistical analyses were conducted using SPSS V 23.0 software calculating and comparing means, standard deviations, medians, and correlation of categorical and ordinate variables. Results: A total of 181 patients with non‐ACEI‐induced angioedema were evaluated with flexible laryngoscopy by otolaryngology. Notably, 11 patients (6.1%) required airway intervention and were successfully intubated. Statistically significant factors (p ≤ 0.05) associated with airway intervention included the diastolic blood pressure (DBP) and mean arterial pressure (MAP) (p = 0.006 and 0.01 respectively), symptoms of dysphonia (p = 0.018), the presence of oropharyngeal, supraglottic, and hypopharyngeal edema (p ≤ 0.001 for each site), and the number of edematous anatomic subsites documented on physical exam (p < 0.001). Other patient demographics, prior history of angioedema, heart rate, systolic blood pressure, symptom onset, number of symptoms at presentation, and medication administered in the ED did not correlate with airway intervention. Conclusion: Dysphonia, DBP, MAP, anatomic location of edema and edema in multiple sites are associated with airway intervention and a higher level of care in non‐ACEI‐induced angioedema and can be useful in risk assessment in patient management. Level of Evidence: 4 Laryngoscope, 134:2282–2287, 2024 [ABSTRACT FROM AUTHOR]

In this article, the influence of nano-silica (NS) added geopolymer-based grout (GBG) mixtures for use in grouting columns was investigated experimentally. For this purpose, the rheological characteristics (shear stress, apparent viscosity, yield stress, plastic viscosity and rheological behaviour) of GBG mixtures obtained with nano-silica (NS) together with fly ash (FA) replacements were measured at a wide range of NS dosages of 0% (only FA for control), 0.5%, 1.0%, 1.5%, 2.0% and 2.5%, and extensive effects of water to binder (w/b) ratios (w/b = 0.50, 0.75, 1.00, 1.25, and 1.50), by dry weight. From a proper and common consistency of water effects (w/b = 1.00), the fresh state properties (mini-slump, Marsh funnel viscometer and bleeding) and unconfined compressive strength (UCS) performance of geopolymer grouting columns were tested. Results of the study indicated that incorporating NS into GBG mixtures had positive effects on the rheological characteristics. The mini-slump and flow time of the Marsh funnel increased slightly with NS dosages up to the rate of 1.5% while increasing the NS proportions led to a reduction of bleeding that was prominent beyond 1.5%NS. Among the treatments of geopolymer mixtures with NS, the highest UCS performance was obtained at the dosage rate of 1.5%NS. [ABSTRACT FROM AUTHOR]

The average energy and multiplicity of prompt γ -rays from slow neutron-induced fission of 235 U have been measured using the STEFF spectrometer at the neutron time-of-flight facility n_TOF. The individual responses from 11 NaI scintillators were corrected for multiple γ -ray interactions, prompt fission neutrons and background counts before being deconvolved to estimate the emitted spectrum of prompt fission γ -rays. The results give an average γ -ray energy E ¯ γ of 1.71(5) MeV and multiplicity ν ¯ γ of 2.66(18) considering γ -rays emitted within the energy range 0.8–6.8 MeV. The n_TOF data has a slightly larger E ¯ γ and smaller ν ¯ γ than other recent measurements, however the product of the two is in agreement within quoted uncertainties. [ABSTRACT FROM AUTHOR]

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Duygu düzenleme becerileri ile bilinçli farkındalık konuları son dönemlerde önem kazanmaya başlanmış iki problem alanıdır. Duygu düzenlemenin bireylerin sağlıklı davranışlar geliştirmesine yardım ettiğini raporlayan çalışmalar mevcuttur. Benzer şekilde bilinçli farkındalığın da duygu düzenlemeye pozitif katkısı olduğunu belirten çalışmalar bulunmaktadır. Bu çalışma bu literatüre duygu düzenleme ve bilinçli farkındalık arasındaki ilişkiye inceleyerek dahil olmaktadır. Çalışmanın amacı ortaokul öğrencilerinin duygu düzenleme becerileri ile bilinçli farkındalık düzeyleri arasındaki ilişkiyi incelemektir. İlişkisel desende tasarlanan bu araştırma rastgele seçilen 345 öğrencinin katılımı ile gerçekleştirilmiştir. Çalışma bulgularına göre öğrencilerin duygu düzenleme becerileri ile bilinçli farkındalık düzeyleri arasında anlamlı bir ilişki mevcuttur. Çalışma, bulgulardan hareketle, öğrencilerin duygu düzenleme kapasitelerini geliştirme maksadı ile bilinçli farkındalık müdahale programlarının geliştirilmesi ve uygulanmasını önererek sonlanmaktadır.

73Ge(n,γ) cross sections were measured at the neutron time-of-flight facility n_TOF at CERN up to neutron energies of 300 keV, providing for the first time experimental data above 8 keV. Results indicate that the stellar cross section at kT=30 keV is 1.5 to 1.7 times higher than most theoretical predictions. The new cross sections result in a substantial decrease of 73Ge produced in stars, which would explain the low isotopic abundance of 73Ge in the solar system. Keywords: Nucleosynthesis, Neutron capture, s process, Germanium, n_TOF

The Filter Inlet for Gases and AEROsols (FIGAERO) is an inlet specifically designed to be coupled with the Aerodyne High-Resolution Time-of-Flight Chemical Ionization Mass Spectrometer (HR-ToF-CIMS). The FIGAERO-HR-ToF-CIMS provides simultaneous molecular information relating to both the gas- and particle-phase samples and has been used to extract vapour pressures (VPs) of the compounds desorbing from the filter whilst giving quantitative concentrations in the particle phase. However, such extraction of vapour pressures of the measured particle-phase components requires use of appropriate, well-defined, reference compounds. Vapour pressures for the homologous series of polyethylene glycols (PEG) ((H-(O-CH2-CH2)n-OH) for n=3 to n=8), covering a range of vapour pressures (VP) (10−1 to 10−7 Pa) that are atmospherically relevant, have been shown to be reproduced well by a range of different techniques, including Knudsen Effusion Mass Spectrometry (KEMS). This is the first homologous series of compounds for which a number of vapour pressure measurement techniques have been found to be in agreement, indicating the utility as a calibration standard, providing an ideal set of benchmark compounds for accurate characterization of the FIGAERO for extracting vapour pressure of measured compounds in chambers and the real atmosphere. To demonstrate this, single-component and mixture vapour pressure measurements are made using two FIGAERO-HR-ToF-CIMS instruments based on a new calibration determined from the PEG series. VP values extracted from both instruments agree well with those measured by KEMS and reported values from literature, validating this approach for extracting VP data from the FIGAERO. This method is then applied to chamber measurements, and the vapour pressures of known products are estimated.

Neutron dark-field imaging is a powerful tool for the spatially resolved characterization of microstructural features of materials and components. Recently, a novel achromatic technique based on a single absorption grating for the concurrent measurement of attenuation, dark-field and differential phase contrast was introduced. However, the range of measurable length scales of the technique in quantitative dark-field measurements appeared limited to some 10–100 nanometers, due to the relatively high spatial resolution requirement to detect the projected beam modulation. Here, we show how using grating–detector distances beyond the resolution limit for a given collimation produces a sequence of inverse and regular projection patterns and, thus, leads to a significant extension of the range of accessible length scales probed by dark-field imaging. In addition, we show that this concept can also be applied to 2D grating structures, which will enable concurrent three-fold directional dark-field measurements at a wide range of length scales. The approach is demonstrated with measurements on an electrical steel sheet sample, which confirm the validity of combining the results from the regular and inverse grating patterns.

Neutron dark-field imaging (DFI) was used to investigate the microstructure of additive manufactured steels. Several DFI methods were combined to assess the microstructure over more than two orders of magnitude in size. Different degrees of porosity and other building features were found depending on the parameters of the selective laser melting additive manufacturing process. A sample built with processing parameters yielding the lowest porosity was deformed which induced a phase transformation of the austenitic phase (fcc) into the martensitic phase (bcc). In the deformed sample an increased dark-field contrast was observed which can only be explained by accounting for the fcc-bcc phase distribution and the magnetic properties of the martensitic phase. We demonstrate that neutron dark-field imaging is well suited to not only detect build flaws like cracks but quantitatively characterize the microstructure in additive manufactured steels.

The neutron capture cross section of 154Gd was measured from 1 eV to 300 keV in the experimental area located 185 m from the CERN n_TOF neutron spallation source, using a metallic sample of gadolinium, enriched to 67% in 154Gd. The capture measurement, performed with four C6D6 scintillation detectors, has been complemented by a transmission measurement performed at the GELINA time-of-flight facility (JRC-Geel), thus minimising the uncertainty related to sample composition. An accurate Maxwellian averaged capture cross section (MACS) was deduced over the temperature range of interest for s process nucleosynthesis modelling. We report a value of 880(50) mb for the MACS at kT=30 keV, significantly lower compared to values available in literature. The new adopted 154Gd(n,γ) cross section reduces the discrepancy between observed and calculated solar s-only isotopic abundances predicted by s-process nucleosynthesis models. Keywords: s process, 154Gd, Neutron time of flight, n_TOF