Search results for "response"
showing 10 items of 4136 documents
Control of the bifunctional O 2 ‐sensor kinase NreB of Staphylococcus carnosus by the nitrate sensor NreA: Switching from kinase to phosphatase state
2019
The NreB-NreC two-component system of Staphylococcus carnosus for O2 sensing cooperates with the accessory nitrate sensor NreA in the NreA-NreB-NreC system for coordinated sensing and regulation of nitrate respiration by O2 and nitrate. ApoNreA (NreA in the absence of nitrate) interacts with NreB and inhibits NreB autophosphorylation (and activation). NreB contains the phosphatase motif DxxxQ. The present study shows that NreB on its own was inactive for the dephosphorylation of the phosphorylated response regulator NreC (NreC-P), but co-incubation with NreB and NreA stimulated NreC-P dephosphorylation. Either the presence of NreA · NO 3 - instead of apoNreA or mutation of the phosphatase m…
Interactive effects of increased temperature and gadolinium pollution in Paracentrotus lividus sea urchin embryos: a climate change perspective
2021
Gradual ocean warming and marine heatwaves represent major threats for marine organisms already facing other anthropogenic-derived hazards, such as chemical contamination in coastal areas. In this study, the combined effects of thermal stress and exposure to gadolinium (Gd), a metal used as a contrasting agent in medical imaging which enters the aquatic environment, were investigated in the embryos and larvae of the sea urchin Paracentrotus lividus. Embryos were exposed to six treatments of three temperatures (18 °C, 21 °C, 24 °C) and two Gd concentrations (control: 0 μM; treated: 20 μM). With respect to developmental progression, increased temperature accelerated development and achievemen…
Balance Perturbations as a Measurement Tool for Trunk Impairment in Cross-Country Sit Skiing
2018
In cross-country sit-skiing, the trunk plays a crucial role in propulsion generation and balance maintenance. Trunk stability is evaluated by automatic responses to unpredictable perturbations; however, electromyography is challenging. The aim of this study was to identify a measure to group sit-skiers according to their ability to control the trunk. Seated in their competitive sit-ski, 10 male and 5 female Paralympic sit-skiers received 6 forward and 6 backward unpredictable perturbations in random order. k-means clustered trunk position at rest, delay to invert the trunk motion, and trunk range of motion significantly into 2 groups. In conclusion, unpredictable perturbations might quantif…
Housing market shocks in italy: A GVAR approach
2020
Abstract In this paper, we use a Global Vector Autoregression (GVAR) model to assess the spatio-temporal mechanism of house price spillovers, also known as “ripple effect”, among 93 Italian provincial housing markets, over the period 2004 − 2016 . In order to better capture the local housing market dynamics, we use data not only on house prices but also on transaction volumes. In particular, we focus on estimating, to what extent, exogenous shocks, interpreted as negative housing demand shocks, arising from 10 Italian regional capitals, impact on their house prices and sales and how these shocks spill over to neighbours housing markets. The negative housing market demand shock hitting the G…
Metabolic detoxification: implications for thresholds.
2000
The fact that chemical carcinogenesis involves single, isolated, essentially irreversible molecular events as discrete steps, several of which must occur in a row to finally culminate in the development of a malignancy, rather suggests that an absolute threshold for chemical carcinogens may not exist. However, practical thresholds may exist due to saturable pathways involved in the metabolic processing, especially in the metabolic inactivation, of such compounds. An important example for such a pathway is the enzymatic hydrolysis of epoxides via epoxide hydrolases, a group of enzymes for which the catalytic mechanism has recently been established. These enzymes convert their substrates via…
The measurement of populist attitudes: Testing cross-national scales using item response theory
2019
Recent research in the populism literature has devoted considerable efforts to the conceptualisation and examination of populism on the individual level, that is, populist attitudes. Despite rapid progress in the field, questions of adequate measurement and empirical evaluation of measures of populist attitudes remain scarce. Seeking to remedy these shortcomings, we apply a cross-national measurement model, using item response theory, to six established and two new populist indicators. Drawing on a cross-national survey (nine European countries, n = 18,368), we engage in a four-folded analysis. First, we examine the commonly used 6-item populism scale. Second, we expand the measurement wit…
Factorial Validity of the General Health Questionnaire 12 in an Angolan Sample
2017
Abstract. Most evidence available has found multidimensional solutions for the General Health Questionnaire’s (GHQ12) structure, contrary to the authors’ original one-factor solution. Recently, the study of method effects associated to negatively worded items has been included in the study of GHQ12’s factor structure, and the most common conclusion has been that the best-fitting structure is a single factor confounded by response bias. Current study analyzes the factor structure of the Portuguese version of the GHQ12. The sample consisted of 1,332 young Angolan adults. Previously-reported structures, including one-factor and multidimensional substantive ones, as well as bifactor structures…
Respuesta sexual en el varón adulto: estudio preliminar
2016
Las personas mayores cada vez otorgan más importancia a la vivencia activa de su sexualidad, lo que choque con algunas de las limitaciones físicas que impone la vejez. El objetivo de este trabajo es acercarnos a la vivencia de la sexualidad en hombres mayores a través de uno de los principales cuestionarios empleados en el estudio de la respuesta sexual masculina: el Índice Internacional de la Función Eréctil. Para ello, 38 hombres de entre 53 y 81 años completaron este y otros instrumentos a través de los cuales se encontró que si bien algunos aspectos de la respuesta sexual (como la función eréctil o el deseo sexual) efectivamente se veían afectados negativamente en hombres mayores, el im…
On the "Strength" of Behavior.
2020
AbstractThe place of the concept of response strength in a natural science of behavior has been the subject of much debate. This article reconsiders the concept of response strength for reasons linked to the foundations of a natural science of behavior. The notion of response strength is implicit in many radical behaviorists’ work. Palmer (2009) makes it explicit by applying the response strength concept to three levels: (1) overt behavior, (2) covert behavior, and (3) latent or potential behavior. We argue that the concept of response strength is superfluous in general, and an explication of the notion of giving causal status to nonobservable events like latent behavior or response strengt…
All bonds are not the same: A response surface analysis of the perceptions of positive bonding relationships in therapy groups
2017
Intrapersonal split alliances were defined as discrepancies in how group members perceived their positive bonding relationships with the group leader, the other group members, and the group-as-a-whole, and were related to group members' outcome. Participants were 168 patients (116 women and 52 men) diagnosed as overweight or obese who participated in 1 of 20, 12-session, therapy groups for weight management. Group members completed the Outcome Questionnaire-45 (OQ-45, Lambert et al., 2004) pre- and posttreatment and the Group Questionnaire (GQ, Krogel et al., 2013) at early, middle and late group sessions. Early, middle, and late ratings were aggregated because bond scores were consistent a…