The western United States is characterized by complex seasonal precipitation regimes due to the hierarchy of climatic controls that operate at different spatial scales. A climatology of month to ...month changes in precipitation, using data from 4027 stations, illustrates how different climatic controls govern the annual cycle of precipitation response and explains the spatial distribution of the seasonal precipitation maximum. These results particularly indicate that smaller-scale climatic controls must be considered along with larger-scale ones in order to explain patterns of spatial climate heterogeneity over mountainous areas. The examination of seasonal precipitation maxima during years characterized by abnormally low winter Pacific-North American teleconnection (PNA) patterns and abnormally strong summer monsoons reveal few changes spatially as compared to normal. The lack of changes illustrate that spatial heterogeneity of precipitation seasonality is the rule rather than the exception for much of the mountainous West. The results of this study offer important implications for scholars interested in assessing spatial climatic variations of the western United States at timescales ranging from inter-annual to the late-quaternary
Obesity-related oxidative stress, the imbalance between pro-oxidants and antioxidants (e.g., nitric oxide), has been linked to metabolic and cardiovascular disease, including endothelial dysfunction ...and atherosclerosis. Reactive oxygen species (ROS) are essential for physiological functions including gene expression, cellular growth, infection defense, and modulating endothelial function. However, elevated ROS and/or diminished antioxidant capacity leading to oxidative stress can lead to dysfunction. Physical activity also results in an acute state of oxidative stress. However, it is likely that chronic physical activity provides a stimulus for favorable oxidative adaptations and enhanced physiological performance and physical health, although distinct responses between aerobic and anaerobic activities warrant further investigation. Studies support the benefits of dietary modification as well as exercise interventions in alleviating oxidative stress susceptibility. Since obese individuals tend to demonstrate elevated markers of oxidative stress, the implications for this population are significant. Therefore, in this review our aim is to discuss (i) the role of oxidative stress and inflammation as associated with obesity-related diseases, (ii) the potential concerns and benefits of exercise-mediated oxidative stress, and (iii) the advantageous role of dietary modification, including acute or chronic caloric restriction and vitamin D supplementation.
Minor changes (~0.1 m/s) in human gait speed are predictive of various measures of decline and can be used to identify at-risk individuals prior to further decline. These associations are possible ...due to an abundance of human clinical research. However, age-related gait changes are not well defined in rodents, even though rodents are used as the primary pre-clinical model for many disease states as well as aging research. Our study investigated the usefulness of a novel automated system, the CatWalk™ XT, to measure age-related differences in gait. Furthermore, age-related functional declines have been associated with decreases in the reduced to oxidized glutathione ratio leading to a pro-oxidizing cellular shift. Therefore the secondary aim of this study was to determine whether chronic glutathione deficiency led to exacerbated age-associated impairments. Groups of male and female wild-type (gclm
) and knock-out (gclm
) mice aged 4, 10 and 17 months were tested on the CatWalk and gait measurements recorded. Similar age-related declines in all measures of gait were observed in both males and females, and chronic glutathione depletion was associated with some delays in age-related declines, which were further exacerbated. In conclusion, the CatWalk is a useful tool to assess gait changes with age, and further studies will be required to identify the potential compensating mechanisms underlying the effects observed with the chronic glutathione depletion.
A previous report of correlations in low-frequency resting-state fluctuations between right and left hemisphere motor cortices in rapidly sampled single-slice echoplanar data is confirmed using a ...whole-body echoplanar MRI scanner at 1.5 T. These correlations are extended to lower sampling rate multislice echoplanar acquisitions and other right/left hemisphere-symmetric functional cortices. The specificity of the correlations in the lower sampling-rate acquisitions is lower due to cardiac and respiratory-cycle effects which are aliased into the pass-band of the low-pass filter. Data are combined for three normal right-handed male subjects. Correlations to left hemisphere motor cortex, visual cortex, and amygdala are measured in long resting-state scans.
The performance of a new historical reanalysis, the NOAA–CIRES–DOE Twentieth Century Reanalysis version 3 (20CRv3), is evaluated via comparisons with other reanalyses and independent observations. ...This dataset provides global, 3-hourly estimates of the atmosphere from 1806 to 2015 by assimilating only surface pressure observations and prescribing sea surface temperature, sea ice concentration, and radiative forcings. Comparisons with independent observations, other reanalyses, and satellite products suggest that 20CRv3 can reliably produce atmospheric estimates on scales ranging from weather events to long-term climatic trends. Not only does 20CRv3 recreate a ‘‘best estimate’’ of the weather, including extreme events, it also provides an estimate of its confidence through the use of an ensemble. Surface pressure statistics suggest that these confidence estimates are reliable. Comparisons with independent upper-air observations in the Northern Hemisphere demonstrate that 20CRv3 has skill throughout the twentieth century. Upper-air fields from 20CRv3 in the late twentieth century and early twenty-first century correlate well with full-input reanalyses, and the correlation is predicted by the confidence fields from 20CRv3. The skill of analyzed 500-hPa geopotential heights from 20CRv3 for 1979–2015 is comparable to that of modern operational 3–4-day forecasts. Finally, 20CRv3 performs well on climate time scales. Long time series and multidecadal averages of mass, circulation, and precipitation fields agree well with modern reanalyses and station- and satellite-based products. 20CRv3 is also able to capture trends in tropospheric-layer temperatures that correlate well with independent products in the twentieth century, placing recent trends in a longer historical context.
ABSTRACT
In 2015, the Hong Kong Institute of Certified Public Accountants issued a standard requiring auditors to communicate key audit matters (KAMs) in the audit report. This standard provides an ...opportunity to examine the effect of KAMs on audit fees and financial reporting quality. Using public companies listed on the Main Board of the Hong Kong Stock Exchange as the treatment group and the companies listed on the Shanghai and Shenzhen Main Board Stock Exchanges as the control group, pre-post and difference-in-differences analyses show that the KAMs standard resulted in improved financial reporting quality but also higher audit fees. Further analyses show that, although the increase in audit fees was related to the risk of material financial statement mis-statements and audit firm business risk, the improvement in financial reporting, which occurred for companies with low financial reporting quality, resulted from the “threat to management of disclosure in KAMs.”
Important audit judgments concerning client selection, audit program planning, and risk assessment all may be impacted by the approach taken to assess risk and to interpret audit evidence. This ...experimental study examines whether auditors’ risk assessments are influenced by the risk assessment approach and by assertion framing. Risk assessment approach was manipulated by eliciting belief-based versus probability-based risk assessments. Assertion framing was manipulated by stating the financial statement assertions to be examined in a positive versus negative form.
Four measures of risk of material misstatement are compared, including one based on the Cobb and Shenoy (2003a, 2003b, 2006) transformation of beliefs into “probabilities.” Both risk assessment approach and assertion framing effects on the auditors’ risk assessments are observed. Given these significant differences, the risk measure(s) the auditor chooses to focus on and the way assertions are framed are shown to be important audit choices in that such choices may impact both audit effectiveness and efficiency.
Evidence for a candidate multiple sclerosis (MS) virus, human herpesvirus 6 (HHV-6), was sought in biopsy specimens of acute lesions that presented clinically as cerebral tumors obtained from 5 ...patients. Histopathology, magnetic resonance imaging, and clinical course confirmed the diagnosis of MS in each case. A sensitive in situ polymerase chain reaction (ISPCR) method was used to detect HHV-6 genome, in conjunction with immunocytochemical staining (ICC) to detect viral and cellular antigens. ISPCR revealed numerous oligodendrocytes, lymphocytes, and microglia containing HHV-6 genome within all lesions, whereas ICC showed only the HHV-6 glycoprotein 116 antigen in some reactive astrocytes and microglia. High frequencies of neuroglial and inflammatory cells containing HHV-6 genome were present in acute-phase lesion tissue from patients who were free of the effects of chronic MS and had not been received immunomodulatory therapy for MS. The prevalence of HHV-6 genome-containing cells, including oligodendrocytes, in each lesion suggests that HHV-6 plays a role in the demyelinative pathogenesis of MS; the significance of the discrepant expression of viral antigens remains uncertain
G protein-coupled receptor kinase 2 (GRK2), a cytosolic enzyme desensitizing G protein-couple receptors (e.g., β-adrenergic receptors β-ARs), is involved in regulation of hypertension, congestive ...heart failure, and inflammatory response. Since cellular GRK2 levels change quickly in response to exogenous/endogenous stimuli, this study examined whether GRK2 levels in human peripheral blood mononuclear cells (PBMCs) would increase during acute aerobic exercise and be associated with plasma IL-6 and cardiorespiratory fitness levels.
Eighteen subjects (8 men and 10 women), ages 18 to 30years, were recruited to perform a 30-minute bout of acute aerobic exercise at 75% VO2max.
Our results demonstrated that women exhibited significantly greater exercise-induced GRK2 expression in PBMCs compared to men. IL-6 modulation is independent of GRK2 expression. Furthermore, the percent change in GRK2 expression was negatively correlated with cardiorespiratory fitness levels (relative VO2max), but not plasma IL-6.
Acute aerobic exercise induces a greater GRK2 expression in women than men, while increased cardiorespiratory fitness is associated with exercise-induced GRK2 expression in PBMCs. Gender could be a contributor to regulate this GRK2 responsiveness to acute aerobic exercise.
A metallic nanoparticle positioned over a metal film offers great advantages as a highly controllable system relevant for probing field-enhancement and other plasmonic effects. Because the size and ...shape of the gap between the nanoparticle and film can be controlled to subnanometer precision using relatively simple, bottom-up fabrication approaches, the film-coupled nanoparticle geometry has recently been applied to enhancing optical fields, accessing the quantum regime of plasmonics, and the design of surfaces with controlled reflectance. In the present work, we examine the plasmon modes associated with a silver nanocube positioned above a silver or gold film, separated by an organic, dielectric spacer layer. The film-coupled nanocube is of particular interest due to the formation of waveguide cavity-like modes between the nanocube and film. These modes impart distinctive scattering characteristics to the system that can be used in the creation of controlled reflectance surfaces and other applications. We perform both experimental spectroscopy and numerical simulations of individual nanocubes positioned over a metal film, finding excellent agreement between experiment and simulation. The waveguide mode description serves as a starting point to explain the optical properties observed.
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