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The adverse effects of tropospheric ozone (O3) on crop photosynthesis, growth and yield have been documented in numerous studies over the last decades, but little information from field experimentation exists on how modern European winter wheat cultivars respond to O3. Two winter wheat cultivars (Astron and Pegassos) differing in development characteristics were exposed to non-filtered ambient air or non-filtered air plus 30 ppb and non-filtered air plus 60 ppb O3 (8 h day−1) in open-top field chambers. At several dates during growth, green leaf area was determined by destructive harvests. Leaf gas exchange, pigment content and xanthophyll cycle activity, and photochemical efficiency by chlorophyll a fluorescence were measured. O3 exposure induced accelerated senescence with no difference between cultivars. Photosynthesis declined especially in Pegassos; however, stomatal conductance was hardly affected by O3. Pigment contents were reduced by O3 exposure, and de-epoxidation index increased. Photochemical efficiency ( Fv/ Fm) declined, whereas actual quantum yield (Φ PSII) did not respond to O3. O3 exposure reduced grain yield in both cultivars. However, yield of Pegassos was more affected by O3 exposure than yield of Astron, suggesting a higher O3 sensitivity of Pegassos. The data presented in this manuscript indicate a need to test whether high-yield varieties such as Pegassos are particularly sensitive to O3 exposure. [ABSTRACT FROM AUTHOR]

An arable crop rotation (winter barley-sugar beet-winter wheat) was exposed to elevated atmospheric CO concentrations ([CO]) using a FACE facility (Free-Air CO Enrichment) during two rotation periods. The atmospheric [CO] of the treatment plots was elevated to 550 ppm during daylight hours (T > 5 °C). Canopy transpiration (E) and conductance (G) were measured at selected intervals (>10% of total growing season) using a dynamic CO/HO chamber measuring system. Plant available soil water content (gravimetry and TDR probes) and canopy microclimate conditions were recorded in parallel. Averaged across both growing seasons, elevated [CO] reduced E by 9%, 18% and 12%, and G by 9%, 17% and 12% in barley, sugar beet and wheat, respectively. Both global radiation (Rg) and vapour pressure deficit (VPD) were the main driving forces of E, whereas G was mostly related to Rg. The responses of E and especially G to [CO] enrichment were insensitive to weather conditions and leaf area index. However, differences in LAI between plots counteracted the [CO] impact on E and thus, at least in part, explained the variability of seasonal [CO] responses between crops and years. As a consequence of lower transpirational canopy water loss, [CO] enrichment increased plant available soil water content in the course of the season by ca. 15 mm. This was true for all crops and years. Lower transpirational cooling due to a [CO]-induced reduction of E increased canopy surface and air temperature by up to 2 °C and 0.5 °C, respectively. This is the first study to address effects of FACE on both water fluxes at canopy scale and water status of a European crop rotation. [ABSTRACT FROM AUTHOR]

Sugar beet ( Beta vulgaris ssp . altissima Döll) was grown in the field under free-air CO2 enrichment (FACE, 550 ppm) and different nitrogen (N) supply (2001: 126 (N100) and 63 kg·ha−1 (N50); 2004: 156 (N100) and 75 kg·ha−1) during two crop rotations. Canopy CO2 exchange rates (CCER) were measured during the main growth phase (leaf area index ≥2) using a dynamic chamber system. Canopy CO2 exchange data were analysed with respect to treatment effects on seasonal means and light use efficiency and light response characteristics. CO2 enrichment enhanced CCER throughout the season. However, in both years, CCER declined after the second half of August independent of radiation and [CO2]. Elevated [CO2] strongly stimulated CCER on a seasonal basis, whereas the reduction of CCER caused by low N was below 10% and not significant. There were no effects of N on daily radiation use efficiency of carbon gain calculated from CCER data, but a strong enhancement by CO2 enrichment. CCER closely tracked diurnal variations in incident photosynthetic photon flux density (PPFD, μmol·m−2·s−1). The relationship between CCER and incident PPFD was curvilinear. In both seasons, initial slopes and maximum rates (CCERmax) were determined from two 6-day periods using these relationships. The first period was measured after canopy closure (first half of July) and the second in the second half of August. In the first period, elevated [CO2] increased the initial slopes. Low N supply affected neither the initial slopes nor their response to elevated [CO2] in either period. In contrast to initial slopes, N stress limited the [CO2] response of CCERmax in the first period. In the second period, however, this interaction of [CO2] and N on CCERmax was completely dominated by a general decline of CCERmax whereas no general decline of the initial slopes occurred in the second period. This response of light response parameters to [CO2] and N suggests that, in sugar beet, the decline of CCER in the late season may rely on limiting mechanisms such as photosynthetic acclimation responses to elevated [CO2] caused by sink limitations. [ABSTRACT FROM AUTHOR]

Background: Objective measures of screen time are necessary to better understand the complex relationship between screen time and health outcomes. However, current objective measures of screen time (e.g., passive sensing applications) are limited in identifying the user of the mobile device, a critical limitation in children's screen time research where devices are often shared across a family. Behavioral biometrics, a technology that uses embedded sensors on modern mobile devices to continuously authenticate users, could be used to address this limitation. Objective: The purpose of this scoping review was to summarize the current state of behavioral biometric authentication and synthesize these findings within the scope of applying behavioral biometric technology to screen time measurement. Methods: We systematically searched five databases (Web of Science Core Collection, Inspec in Engineering Village, Applied Science & Technology Source, IEEE Xplore, PubMed), with the last search in September of 2022. Eligible studies were on the authentication of the user or the detection of demographic characteristics (age, gender) using built-in sensors on mobile devices (e.g., smartphone, tablet). Studies were required to use the following methods for authentication: motion behavior, touch, keystroke dynamics, and/or behavior profiling. We extracted study characteristics (sample size, age, gender), data collection methods, data stream, model evaluation metrics, and performance of models, and additionally performed a study quality assessment. Summary characteristics were tabulated and compiled in Excel. We synthesized the extracted information using a narrative approach. Results: Of the 14,179 articles screened, 122 were included in this scoping review. Of the 122 included studies, the most highly used biometric methods were touch gestures (n = 76) and movement (n = 63), with 30 studies using keystroke dynamics and 6 studies using behavior profiling. Of the studies that reported age (47), most were performed exclusively in adult populations (n = 34). The overall study quality was low, with an average score of 5.5/14. Conclusion: The field of behavioral biometrics is limited by the low overall quality of studies. Behavioral biometric technology has the potential to be used in a public health context to address the limitations of current measures of screen time; however, more rigorous research must be performed in child populations first. Systematic review registration: The protocol has been pre-registered in the Open Science Framework database (https://doi.org/10.17605/OSF.IO/92YCT). [ABSTRACT FROM AUTHOR]

The rise of atmospheric CO2 concentration ([ CO2]) affects stomatal conductance and thus transpiration and leaf temperature. We evaluated the effect of elevated [ CO2] levels under different water supply on daily sap flow and canopy microclimate (air temperature (Tc) and vapour pressure deficit ( VPD)) of maize. The crop was cultivated in circular field plots under ambient ( AMB, 378 μmol mol−1) and elevated [ CO2] ( FACE, 550 μmol mol−1) using free-air CO2 enrichment with sufficient water in 2007, while in 2008 a DRY semicircle received only half as much water as compared to the WET semicircle from mid of July. In 2007, sap flow was measured in WET simultaneously under AMB and FACE conditions and was significantly decreased by elevated [ CO2]. In 2008, sap flow was measured in all four treatments but not simultaneously. Therefore, data were correlated with potential evaporation and the slopes were used to determine treatment effects. Drought reduced whole-plant transpiration by 50 % and 37 % as compared to WET conditions under AMB and FACE, respectively. Moreover, CO2 enrichment did not affect sap flow under drought but decreased it under WET by 20 % averaged over both years. The saving of water in the period before the drought treatment resulted in a displacement of dry soil conditions under FACE as compared to AMB. Under WET, CO2 enrichment always increased Tc and VPD during the day. Under DRY, FACE plots were warmer and drier most of the time in August, but cooler and damper short after the start of drought in July and from the end of August onwards. Thus, the CO2 effect on transpiration under drought was variable and detectable rather easy by measuring canopy microclimate. [ABSTRACT FROM AUTHOR]

Background: Pilot/feasibility studies play an important role in the development and refinement of behavioral interventions by providing information about feasibility, acceptability, and potential efficacy. Despite their importance and wide-spread use, the approaches taken by behavioral scientists to scale-up early-stage studies to larger-scale trials has received little attention. The aim of our study was to understand the role that pilot studies play in the development and execution of larger-scale trials. Methods: We conducted interviews with childhood obesity researchers who had published pilot behavioral interventions and larger-scale trials of the same or similar interventions. Questions were asked about the role of pilot studies in developing larger-scale trials and the challenges encountered when scaling-up an intervention based upon pilot findings. Data were coded and analyzed using an inductive analytic approach to identify themes. Results: Twenty-four interventionists (54% women, 37–70 years old, mean 20 years since terminal degree) completed a total of 148 pilot studies across their careers (mean 6.4, range 1–20), of which 59% were scaled-up. Scaling was described as resource intensive and pilot work was considered essential to successfully competing for funding by 63% of the sample (n = 15). When asked to define a high-quality pilot study, interventionists described studies that allowed them to evaluate two independent factors: components of their intervention (e.g., acceptability, feasibility) and study parameters (e.g., sample size, measures). Interventionists expressed that more process implementation measures, different study designs, and additional iterations could improve decisions to scale-up. Most agreed that pilot studies were likely to produce inflated estimates of potential efficacy though only nine interventionists provided potential solutions for decreasing inflated measures of efficacy. Suggested major causes of inflated effects included high levels of oversight in pilot studies (e.g., researcher support), reliance on subjective measures, and utilizing convenience or highly motivated samples. Potential solutions included designing pilots for real-world implementation, only conducting randomized controlled pilot studies, and pre-registering pilot studies. Conclusions: Pilot studies purposes are multifaceted and deemed essential to obtaining funding for larger-scale trials. Clarifying the form and function of preliminary, early-stage research may enhance the productive utilization of early-stage studies and reduced drops in efficacy when transitioning to larger scale studies. [ABSTRACT FROM AUTHOR]

ID57b"In the pilot study we had teachers delivering intervention and in the main trial we went to the core non-degree staff delivering the intervention. We were embedded in the local school boards and they saw it as very useful from both a health and an educational point of view and the larger scale trial was really just a larger scale longer version of the pilot study." ID13 ChallengesChallenges encountered when scaling pilot studies12a"In the pilot we had a small amount of group of teachers who were very motivated and who want to bring about a change but in our larger trial we had multiple teachers, multiple schools. [Extracted from the article]

Background: Pilot/feasibility studies play an important role in the development and refinement of behavioral interventions by providing information about feasibility, acceptability, and potential efficacy. Despite their importance and wide-spread use, the approaches taken by behavioral scientists to scale-up early-stage studies to larger-scale trials has received little attention. The aim of our study was to understand the role that pilot studies play in the development and execution of larger-scale trials. Methods: We conducted interviews with childhood obesity researchers who had published pilot behavioral interventions and larger-scale trials of the same or similar interventions. Questions were asked about the role of pilot studies in developing larger-scale trials and the challenges encountered when scaling-up an intervention based upon pilot findings. Data were coded and analyzed using an inductive analytic approach to identify themes. Results: Twenty-four interventionists (54% women, 37–70 years old, mean 20 years since terminal degree) completed a total of 148 pilot studies across their careers (mean 6.4, range 1–20), of which 59% were scaled-up. Scaling was described as resource intensive and pilot work was considered essential to successfully competing for funding by 63% of the sample (n = 15). When asked to define a high-quality pilot study, interventionists described studies that allowed them to evaluate two independent factors: components of their intervention (e.g., acceptability, feasibility) and study parameters (e.g., sample size, measures). Interventionists expressed that more process implementation measures, different study designs, and additional iterations could improve decisions to scale-up. Most agreed that pilot studies were likely to produce inflated estimates of potential efficacy though only nine interventionists provided potential solutions for decreasing inflated measures of efficacy. Suggested major causes of inflated effects included high levels of oversight in pilot studies (e.g., researcher support), reliance on subjective measures, and utilizing convenience or highly motivated samples. Potential solutions included designing pilots for real-world implementation, only conducting randomized controlled pilot studies, and pre-registering pilot studies. Conclusions: Pilot studies purposes are multifaceted and deemed essential to obtaining funding for larger-scale trials. Clarifying the form and function of preliminary, early-stage research may enhance the productive utilization of early-stage studies and reduced drops in efficacy when transitioning to larger scale studies. [ABSTRACT FROM AUTHOR]

Primary objective : To understand the temporal evolution of brain reorganization during recovery from stroke. Research design : A patient who suffered left middle cerebral artery stroke 9 months earlier was studied on three occasions, ∼⃒1 month apart. Methods and procedures : Brain activation was studied using functional Magnetic Resonance Imaging (fMRI). During each session, the patient performed a finger-to-thumb opposition task, which involved one bimanual and two unimanual conditions. Each condition consisted of overt movement of fingers and imagery of the same task. Results : With recovery, greater recruitment was observed of the affected primary motor cortex (M1) and a decrease in activation of the unaffected M1 and supplementary motor area. In addition, the widespread activation of brain areas seen during the initial session changed to a more focused pattern of activation as the patient recovered. Imagery tasks resulted in similar brain activity as overt execution pointing to imagery as a potential tool for rehabilitation. [ABSTRACT FROM AUTHOR]

Questions: Are there losses in species richness due to extinctions? Is the input of new species lower in environments with strong resource limitation? Is there a decrease in abundance and diversity of native species due to anthropogenic disturbance at local and regional scale? Has abundance of exotic species been favoured by grazing increased? Are floristic changes associated with homogenization processes?. Location: Two grassland community types of the Argentine Flooding Pampas: themesophyte prairie and the halophyte steppe. Methods: Grassland sites (n = 51) were resurveyed with the same methodology after 35 yr. At the local scale (0.25 ha),we analysed alpha diversity, site colonization and extinction rates, and changes in species and functional type composition. Site colonization rates were calculated separately for new species (not recorded in the original inventory) and old species (present in the first survey at other sample sites of the community). Correspondence analysis was applied to the presence/absence species matrix for all sites in both periods. At regional scale, we evaluated gamma diversity, heterogeneity within and between communities, changes in proportion of functional types (growth season, longevity and life form) and species origin. Results: In themesophytic prairie, average local species richness increased 46% and regional richness 28%, while in the halophytic steppe changes were not significant. The colonization rate was higher and the extinction rate lower in the richest community (mesophytic prairie). Differences in colonization rates between natives and exotics were not found. Principal variability between sites in species composition was associated with abiotic conditions explaining 20.9% of inertia, temporal changes were relegated to the second axis with 6.38%. Proportions of warm-season exotics among newarrivalswere higher than expected. Biotic homogenization was evidenced in the mesophytic prairie as a significant reduction in species turnover between sampling dates. Conclusions: After 35 yr under moderate grazing intensity we found increases in species richness, no biodiversity loss and no losses of native species. Instead of those species favoured by grazing, as expected, warm season species increased. Different grassland communities showed clear differences in richness changes, in degree of homogenization and in species turnover. [ABSTRACT FROM AUTHOR]

Summary • The predictive capacity of two simulation models with different degrees of complexity for the calculation of assimilate production, was tested at different time scales, using a data set of wheat grown in an open-top-chamber experiment at two CO2 concentrations. • Observed values of net canopy assimilation (Pn) were obtained from wheat plants grown at ambient (410 µmol mol-1 ) and elevated (680 µmol mol-1 ) CO2 mole fractions. Pn was simulated by using either simple multiple regression equations (AFRCWHEAT2) or by highly detailed calculations of leaf energy balances and the coupling of photosynthesis with stomatal conductance (LINTULCC2). • Irrespective of the developmental stage of the crop or variation in weather, the models accurately simulated canopy assimilation and growth. We conclude that the response of aboveground-biomass production to elevated CO2 concentrations was explained primarily by the effects of CO2 on radiation-use efficiency and assimilate production. • The models explained satisfactorily the daily course of Pn, its integrated daily totals, and the seasonally produced aboveground biomass, both at ambient and elevated CO2 concentrations. Specific problems in the simulations were identified and discussed. [ABSTRACT FROM AUTHOR]