Onset Of Regulation Research Articles

Regulation of locomotor pointing across the lifespan: Investigating age-related influences on perceptual-motor coupling.

IntroductionThe regulation of one’s step length by placing one’s foot at a specific position within gait, otherwise known as ‘locomotor pointing’, is well understood in walking and running gait. The current study was the first to broaden this understanding to a larger cohort and to describe the influence of age on the regulation of locomotor pointing when walking up to and stepping onto a curb-like platform.MethodsYounger (n = 17, mean age: 25.35 years, range: 19–33) and older adults (n = 105, mean age: 71.49 years, range: 61–86) participated in a walking experiment, requiring them to approach and step onto a curb-like platform. Linear mixed effects modeling was used to study the main outcome variables: onset of regulation, the regulation strategy and the strength of perceptual-motor coupling.ResultsResults showed that with older age, participants showed less variability in foot placement during their approach and seemed to prefer to shorten their steps. Furthermore, the strength of the perceptual-motor relationship was found to be related to age; regulation of step length of both younger and older participants was based on a participant’s current foot position. The strength of this relationship increased as participants got closer to the curb and was stronger with increasing age. Furthermore, younger adults on average lengthened their steps as they got closer to the curb, whereas older adults showed significantly less lengthening compared to their younger counterparts. No age-related differences were found in terms of onset of regulation.DiscussionThe results suggest that the strength of the perceptual-motor relationship in gait is related to age. It is argued that this age-related increase in the strength of perceptual-motor coupling is required to cope with increasing demands linked to the age-related declines of action capabilities. The implications of the findings are discussed in the context of increased falls risks and deficits in perceptual-motor functioning.

Diminished dynamic cerebral autoregulatory capacity with forced oscillations in mean arterial pressure with elevated cardiorespiratory fitness

The effect that cardiorespiratory fitness has on the dynamic cerebral autoregulatory capacity during changes in mean arterial pressure (MAP) remains equivocal. Using a multiple‐metrics approach, challenging MAP across the spectrum of physiological extremes (i.e., spontaneous through forced MAP oscillations), we characterized dynamic cerebral autoregulatory capacity in 19 male endurance athletes and eight controls via three methods: (1) onset of regulation (i.e., time delay before an increase in middle cerebral artery (MCA) conductance [MCA blood velocity (MCAv)/MAP] and rate of regulation, after transient hypotension induced by sit‐to‐stand, and transfer function analysis (TFA) of MAP and MCAv responses during (2) spontaneous and (3) forced oscillations (5‐min of squat‐stand maneuvers performed at 0.05 and 0.10 Hz). Reductions in MAP and mean MCAv (MCAV mean) during initial orthostatic stress (0‐30 sec after sit‐to‐stand) and the prevalence of orthostatic hypotension were also determined. Onset of regulation was delayed after sit‐to‐stand in athletes (3.1 ± 1.7 vs. 1.5 ± 1.0 sec; P = 0.03), but rate of regulation was not different between groups (0.24 ± 0.05 vs. 0.21 ± 0.09 sec−1; P = 0.82). While both groups had comparable TFA metrics during spontaneous oscillations, athletes had higher TFA gain during 0.10 Hz squat‐stand versus recreational controls (P = 0.01). Reductions in MAP (P = 0.15) and MCAV mean (P = 0.11) during orthostatic stress and the prevalence of initial orthostatic hypotension (P = 0.65) were comparable between groups. These results indicate an intact ability of the cerebral vasculature to react to spontaneous oscillations but an attenuated capability to counter rapid and large changes in MAP in individuals with elevated cardiorespiratory fitness.

Sensor transition failure in the high flow sampler: Implications for methane emission inventories of natural gas infrastructure

Quantification of leaks from natural gas (NG) infrastructure is a key step in reducing emissions of the greenhouse gas methane (CH4), particularly as NG becomes a larger component of domestic energy supply. The U.S. Environmental Protection Agency (EPA) requires measurement and reporting of emissions of CH4 from NG transmission, storage, and processing facilities, and the high-flow sampler (or high-volume sampler) is one of the tools approved for this by the EPA. The Bacharach Hi-Flow Sampler (BHFS) is the only commercially available high-flow instrument, and it is also used throughout the NG supply chain for directed inspection and maintenance, emission factor development, and greenhouse gas reduction programs. Here we document failure of the BHFS to transition from a catalytic oxidation sensor used to measure low NG (~5% or less) concentrations to a thermal conductivity sensor for higher concentrations (from ~5% to 100%), resulting in underestimation of NG emission rates. Our analysis includes both our own field testing and analysis of data from two other studies (Modrak et al., 2012; City of Fort Worth, 2011). Although this failure is not completely understood, and although we do not know if all BHFS models are similarly affected, sensor transition failure has been observed under one or more of these conditions: (1) Calibration is more than ~2 weeks old; (2) firmware is out of date; or (3) the composition of the NG source is less than ~91% CH4. The extent to which this issue has affected recent emission studies is uncertain, but the analysis presented here suggests that the problem could be widespread. Furthermore, it is critical that this problem be resolved before the onset of regulations on CH4 emissions from the oil and gas industry, as the BHFS is a popular instrument for these measurements.Implications: An instrument commonly used to measure leaks in natural gas infrastructure has a critical sensor transition failure issue that results in underestimation of leaks, with implications for greenhouse gas emissions estimates as well as safety.

A dual process for the cognitive control of emotional significance: implications for emotion regulation and disorders of emotion

A dual process for the cognitive control of emotional significance: implications for emotion regulation and disorders of emotion

<p><strong>On the spelling of <em>Antrechinus nordenskjoldi </em>(Echinodermata: Echinoidea)*</strong></p>

The spelling of organism names seems to be a trivial matter. A brief glance at the scientific literature, however, shows that it is far from that. In some cases, delving into these seemingly minor or even unimportant issues of spelling can turn up historical information germane to our science. Apart from simple misspellings and printing errors, differing ideas about the formation of names and the late onset of regulations (ICZN, ICBN) covering the naming and use of names are sources for different spellings. It was not until 1905 that a first internationally accepted version of what we now know as “the Code” was published under the name “Règles internationales de la Nomenclature Zoologique adoptées par les Congrès Internationaux de Zoologie”. The Code kept being emended after this first attempt to provide a unified set of rules for the naming and treatment of names and today, for animals, the 4th edition of the Code is valid (ICZN 1999).

How does the brain regulate negative bias to stigma?

The current study uses functional magnetic resonance imaging (fMRI) to examine whether regulating negative bias to stigmatized individuals has a unique neural activity profile from general emotion regulation. Participants were presented with images of stigmatized (e.g. homeless people) or non-stigmatized (e.g. a man holding a gun) social targets while undergoing fMRI and were asked either to maintain or regulate their emotional response. Their implicit bias toward these stigmatized group members was also measured. Analyses were conducted in both, an event-related fashion, considering the event to be the onset of regulation, and in a blocked-design fashion, considering the sustained activity throughout the 8-s regulatory period. In the event-related (onset) analyses, participants showed more activity throughout the prefrontal cortex when initiating a regulatory response to stigmatized as compared with non-stigmatized images. This neural activity was positively correlated with their implicit bias. Interestingly, in the block (sustained) analyses, general emotion regulation elicited a more widespread pattern of neural activity as compared with stigma regulation. This activity was largely posterior, suggesting that general emotion regulation may engage more visuo-spatial processing as compared with stigma regulation. These findings suggest that regulating negative affect toward stigmatized targets may occur relatively more quickly than regulating negative affect toward non-stigmatized targets.

Long-Term Responses of River-Margin Vegetation to Water-Level Regulation

The long-term effect of water-level regulation on riparian plant communities was assessed for storage reservoirs and run-of-river impoundments. Soon after the onset of regulation, there were few species and sparse vegetation cover, regardless of whether the new water level intersected former upland or riparian vegetation. In the longer term, an impoverished vegetation was maintained by storage reservoirs, whereas in run-of-river impoundments, some community characteristics deteriorated and others recovered compared to adjacent free-flowing rivers.

The dependence of the content in the blood of potassium and calcium on the activity of the ovary

The dependence of the content of potassium and calcium in the blood on the activity of the ovary was studied by Schultze (Arch. F. G., Bd. 126, 1925), according to whose studies, 1-2 days before the onset of regulation, the content of K decreases.