Methodological Realities: Social Science Methods and Business Reorganizations

The objective of this Article is to argue that our methods are appropriate for analyzing business bankruptcy as a class of human and organizational behavior

Exercise capacity and incidence of myocardial perfusion defects after Kawasaki disease in children and adolescents

Objectives.This study evaluated exercise performance and myocardial perfusion during exercise in patients with Kawasaki disease who had a broad spectrum of residual coronary abnormalities.Background.Reports of exercise performance after Kawasaki disease have generally included a small number of patients evaluated by various protocols, frequently with incomplete data. Myocardial perfusion studies have usually been limited to those using pharmacologically induced coronary vasodilation. Therefore, to our knowledge there has not been a large study directly correlating exercise performance, electrocardiographic (ECG) changes and myocardial perfusion imaging.Methods.Forty-six patients were classified into three groups on the basis of coronary artery status: group 1 (n = 27) had no objective evidence of coronary artery lesions; group 2 (n = 11) had resolved aneurysms; group 3 (n = 8) had persistent coronary aneurysms. All patients underwent exercise testing with monitor ing of ECG changes and oxygen consumption. Single-photon emission computed tomographic imaging was performed at rest and during peak exercise using technetium-99m sestamibi.Results.Maximal oxygen consumption was within normal limits and was similar for all three groups. Five patients had mild ST segment changes at peak exercise. Two of these patients had stress-induced perfusion defects. Myocardial perfusion defects were present in 37% of patients in group 1, 63% in group 2 and 100% in group 3. Perfusion defects corresponded to the coronary artery lesion site in all but three patients.Conclusions.Maximal oxygen consumption is normal after Kawasaki disease regardless of coronary artery status. Stressinduced perfusion defects are frequent even in the absence of coronary abnormalities and are common in the absence of ST segment changes suggestive of ischemia

Assessment of online water-soluble brown carbon measuring systems for aircraft sampling

Brown carbon (BrC) consists of particulate organic species that preferentially absorb light at visible and ultraviolet wavelengths. Ambient studies show that as a component of aerosol particles, BrC affects photochemical reaction rates and regional to global climate. Some organic chromophores are especially toxic, linking BrC to adverse health effects. The lack of direct measurements of BrC has limited our understanding of its prevalence, sources, evolution, and impacts. We describe the first direct, online measurements of water-soluble BrC on research aircraft by three separate instruments. Each instrument measured light absorption over a broad wavelength range using a liquid waveguide capillary cell (LWCC) and grating spectrometer, with particles collected into water by a particle-into-liquid sampler (CSU PILS-LWCC and NOAA PILS-LWCC) or a mist chamber (MC-LWCC). The instruments were deployed on the NSF C-130 aircraft during WE-CAN 2018 as well as the NASA DC-8 and the NOAA Twin Otter aircraft during FIREX-AQ 2019, where they sampled fresh and moderately aged wildfire plumes. Here, we describe the instruments, calibrations, data analysis and corrections for baseline drift and hysteresis. Detection limits (3σ) at 365 nm were 1.53 Mm−1 (MC-LWCC; 2.5 min sampling time), 0.89 Mm−1 (CSU PILS-LWCC; 30 s sampling time), and 0.03 Mm−1 (NOAA PILS-LWCC; 30 s sampling time). Measurement uncertainties were 28 % (MC-LWCC), 12 % (CSU PILS-LWCC), and 11 % (NOAA PILS-LWCC). The MC-LWCC system agreed well with offline measurements from filter samples, with a slope of 0.91 and R2=0.89. Overall, these instruments provide soluble BrC measurements with specificity and geographical coverage that is unavailable by other methods, but their sensitivity and time resolution can be challenging for aircraft studies where large and rapid changes in BrC concentrations may be encountered

MSH2–MSH6 stimulates DNA polymerase η, suggesting a role for A:T mutations in antibody genes

Activation-induced cytidine deaminase deaminates cytosine to uracil (dU) in DNA, which leads to mutations at C:G basepairs in immunoglobulin genes during somatic hypermutation. The mechanism that generates mutations at A:T basepairs, however, remains unclear. It appears to require the MSH2–MSH6 mismatch repair heterodimer and DNA polymerase (pol) η, as mutations of A:T are decreased in mice and humans lacking these proteins. Here, we demonstrate that these proteins interact physically and functionally. First, we show that MSH2–MSH6 binds to a U:G mismatch but not to other DNA intermediates produced during base excision repair of dUs, including an abasic site and a deoxyribose phosphate group. Second, MSH2 binds to pol η in solution, and endogenous MSH2 associates with the pol in cell extracts. Third, MSH2–MSH6 stimulates the catalytic activity of pol η in vitro. These observations suggest that the interaction between MSH2–MSH6 and DNA pol η stimulates synthesis of mutations at bases located downstream of the initial dU lesion, including A:T pairs

Global ecological predictors of the soil priming effect.

Identifying the global drivers of soil priming is essential to understanding C cycling in terrestrial ecosystems. We conducted a survey of soils across 86 globally-distributed locations, spanning a wide range of climates, biotic communities, and soil conditions, and evaluated the apparent soil priming effect using 13C-glucose labeling. Here we show that the magnitude of the positive apparent priming effect (increase in CO2 release through accelerated microbial biomass turnover) was negatively associated with SOC content and microbial respiration rates. Our statistical modeling suggests that apparent priming effects tend to be negative in more mesic sites associated with higher SOC contents. In contrast, a single-input of labile C causes positive apparent priming effects in more arid locations with low SOC contents. Our results provide solid evidence that SOC content plays a critical role in regulating apparent priming effects, with important implications for the improvement of C cycling models under global change scenarios

Sensory reactivity, empathizing and systemizing in autism spectrum conditions and sensory processing disorder.

Although the DSM-5 added sensory symptoms as a criterion for ASC, there is a group of children who display sensory symptoms but do not have ASC; children with sensory processing disorder (SPD). To be able to differentiate these two disorders, our aim was to evaluate whether children with ASC show more sensory symptomatology and/or different cognitive styles in empathy and systemizing compared to children with SPD and typically developing (TD) children. The study included 210 participants: 68 children with ASC, 79 with SPD and 63 TD children. The Sensory Processing Scale Inventory was used to measure sensory symptoms, the Autism Spectrum Quotient (AQ) to measure autistic traits, and the Empathy Quotient (EQ) and Systemizing Quotient (SQ) to measure cognitive styles. Across groups, a greater sensory symptomatology was associated with lower empathy. Further, both the ASC and SPD groups showed more sensory symptoms than TD children. Children with ASC and SPD only differed on sensory under-reactivity. The ASD group did, however, show lower empathy and higher systemizing scores than the SPD group. Together, this suggest that sensory symptoms alone may not be adequate to differentiate children with ASC and SPD but that cognitive style measures could be used for differential diagnosis