scholarly journals Review and parameterisation of bi-directional ammonia exchange between vegetation and the atmosphere

2010 ◽  
Vol 10 (4) ◽  
pp. 10335-10398 ◽  
Author(s):  
R.-S. Massad ◽  
E. Nemitz ◽  
M. A. Sutton
Keyword(s):  
Meta Analysis ◽  
N Deposition ◽  
Transport Models ◽  
Total N ◽  
N Input ◽  
Main Driver ◽  
Fertiliser Application ◽  
Ammonia Exchange ◽  
Managed Ecosystems ◽  
Solubility Equilibrium

Abstract. Current deposition schemes used in atmospheric chemical transport models do not generally account for bi-directional exchange of ammonia (NH3). Bi-directional exchange schemes, which have so far been applied at the plot scale, can be included in transport models, but need to be parameterised with appropriate values of the stomatal compensation point (χs) and cuticular resistance (Rw). We here review existing measurements of χs as well as Rw and compile a comprehensive dataset from which we then propose generalised parameterisations. χs is related to Γs, the non-dimensional ratio of [NH4+]apo and [H+]apo in the apoplast, through the temperature dependence of the combined Henry and solubility equilibrium. The meta-analysis suggests that the nitrogen (N) input is the main driver of the apoplastic and bulk leaf concentrations of ammonium (NH+4 apo, NH+4 bulk). For managed ecosystems, the main source of N is fertilisation which is reflected in a peak value of χs a few days following application, but also alters seasonal values of NH+4 apo and NH+4 bulk. We propose a parameterisation for χs which includes peak values as a function of amount and type of fertiliser application which gradually decreases to a background value. The background χs is set based on total N input to the ecosystem as a yearly fertiliser application and N deposition (Ndep). For non-managed ecosystems, χs is parameterised based solely on the link with Ndep. For Rw we propose a general parameterisation as a function of atmospheric Relative Humidity (RH), incorporating a minimum value (R w(min)), which depends on the ratio of atmospheric acid concentrations (SO2, HNO3 and HCl) to NH3 concentrations. The parameterisations are based mainly on datasets from temperate locations in northern Europe making them most suitable for up-scaling in these regions (Unified EMEP model for example). In principle, the parameterisations should be applicable to other climates, though there is a need for more underpinning data, with the uncertainties being especially large for tropical and subtropical conditions.

scholarly journals Review and parameterisation of bi-directional ammonia exchange between vegetation and the atmosphere

2010 ◽  
Vol 10 (21) ◽  
pp. 10359-10386 ◽  
Author(s):  
R.-S. Massad ◽  
E. Nemitz ◽  
M. A. Sutton
Keyword(s):  
Meta Analysis ◽  
Chemical Transport ◽  
Compensation Point ◽  
Transport Models ◽  
Dissociation Equilibrium ◽  
Chemical Transport Models ◽  
N Input ◽  
Main Driver ◽  
Ammonia Exchange ◽  
Cuticular Resistance

Abstract. Current deposition schemes used in atmospheric chemical transport models do not generally account for bi-directional exchange of ammonia (NH3). Bi-directional exchange schemes, which have so far been applied at the plot scale, can be included in transport models, but need to be parameterised with appropriate values of the ground layer compensation point (χg), stomatal compensation point (χs) and cuticular resistance (Rw). We review existing measurements of χg, χs as well as Rw and compile a comprehensive dataset from which we then propose generalised parameterisations. χs is related to Γs, the non-dimensional ratio of [NH4+]apo and [H+]apo in the apoplast, through the temperature dependence of the combined Henry and dissociation equilibrium. The meta-analysis suggests that the nitrogen (N) input is the main driver of the apoplastic and bulk leaf concentrations of ammonium (NH4 apo

Temporal Discounting Across Adulthood: A Systematic Review and Meta-analysis

2020 ◽  
Author(s):  
Kendra Leigh Seaman ◽  
Sade J Abiodun ◽  
Zöe Fenn ◽  
Gregory Russell Samanez-Larkin ◽  
Rui Mata
Keyword(s):  
Age Differences ◽  
Intertemporal Choice ◽  
Meta Analysis ◽  
Empirical Work ◽  
Adult Life ◽  
Temporal Discounting ◽  
Total N ◽  
Adult Age ◽  
Adult Age Differences ◽  
Choice Tasks

A number of developmental theories have been proposed that make differential predictions about the links between age and temporal discounting; that is, the valuation of rewards at different points in time. Most empirical studies examining adult age differences in temporal discounting have relied on economic intertemporal choice tasks, which pit choosing a smaller, sooner monetary reward against choosing a larger, later one. Although initial studies using these tasks suggested older adults discount less than younger adults, follow-up studies provided heterogeneous, and thus inconclusive, results. Using an open science approach, we test the replicability of adult age differences in temporal discounting by conducting a preregistered systematic literature search and meta-analysis of adult age differences in intertemporal choice tasks. Across 37 cross-sectional studies (Total N = 104,736), we found no reliable relation between age and temporal discounting (r = -0.081, 95% CI [-0.185, 0.025]). We also found little evidence of publication bias or p-hacking. Exploratory analyses of moderators found no effect of experimental design (e.g., extreme-group vs. continuous age), incentives (hypothetical vs. rewards), amount of delay (e.g., days, weeks, months, or years), or quantification of discounting behavior (e.g., proportion of immediate choices vs. parameters from computational modeling). Additional analyses of 12 participant-level data sets found little support for a nonlinear relation between age and temporal discounting across adulthood. Overall, the results suggest that adult age is not reliably associated with individual differences in temporal discounting. We provide recommendations for future empirical work on temporal discounting across the adult life span.

Political bullshit receptivity and its correlates: a cross-cultural validation of the concept

2020 ◽  
Author(s):  
Vukašin Gligorić ◽  
Allard Feddes ◽  
Bertjan Doosje
Keyword(s):  
The Netherlands ◽  
Political Ideology ◽  
Voting Behavior ◽  
Free Market ◽  
Meta Analysis ◽  
The United States ◽  
Persuasive Communication ◽  
Lower Probability ◽  
Left Wing ◽  
Total N

Frankfurt defined persuasive communication that has no regard for truth, knowledge, or evidence as bullshit. Although there has been a lot of psychological research on pseudo-profound bullshit, no study examined this type of communication in politics. In the present research, we operationalize political bullshit receptivity as endorsing vague political statements, slogans, and political bullshit programs. We investigated the relationship of these three measures with pseudo-profound bullshit, ideology (political ideology, support for neoliberalism), populism, and voting behavior. Three pre-registered studies in different cultural settings (the United States, Serbia, The Netherlands; total N = 534) yielded medium to high intercorrelations between political bullshit measures and pseudo-profound bullshit, and good construct validity (hypothesized one-factor solution). A Bayesian meta-analysis showed that all political bullshit measures positively correlated with support for the free market, while only some positively correlated with social (political statements and programs) and economic conservatism (programs), and populism (programs). In the U.S., higher receptivity to political bullshit was associated with a higher probability that one voted for Trump (vs Clinton) in the past and higher intentions to vote for Trump (vs Biden and Sanders). In the Netherlands, higher receptivity to political bullshit predicted the intention to vote for the conservative-liberal People's Party for Freedom and Democracy. Exploratory analyses on merged datasets showed that higher receptivity to political bullshit was associated with a higher probability to vote for right-wing candidates/parties and lower probability for the left-wing ones. Overall, political bullshit endorsement showed good validity, opening avenues for research in political communication, especially when this communication is broad and meaningless.

scholarly journals Sense of Purpose in Life Is Associated with Lower Risk of Incident Dementia: A Meta-Analysis

2021 ◽  
pp. 1-10
Author(s):  
Angelina R. Sutin ◽  
Damaris Aschwanden ◽  
Martina Luchetti ◽  
Yannick Stephan ◽  
Antonio Terracciano
Keyword(s):  
Lower Risk ◽  
Meta Analysis ◽  
Random Effect ◽  
Purpose In Life ◽  
Population Based ◽  
Primary Data ◽  
Or Education ◽  
Total N ◽  
Sense Of Purpose ◽  
Incident Dementia

Background: A sense of purpose in life has been associated with healthier cognitive outcomes across adulthood, including risk of dementia. The robustness and replicability of this association, however, has yet to be evaluated systematically. Objective: To test whether a greater sense of purpose in life is associated with lower risk of dementia in four population-based cohorts and combined with the published literature. Methods: Random-effect meta-analysis of prospective studies (individual participant data and from the published literature identified through a systematic review) that examined sense of purpose and risk of incident dementia. Results: In six samples followed up to 17 years (four primary data and two published; total N = 53,499; n = 5,862 incident dementia), greater sense of purpose in life was associated with lower dementia risk (HR = 0.77, 95%CI = 0.73–0.81, p <  0.001). The association was generally consistent across cohorts (I2 = 47%), remained significant controlling for clinical (e.g., depression) and behavioral (e.g., physical inactivity) risk factors, and was not moderated by age, gender, or education. Conclusion: Sense of purpose is a replicable and robust predictor of lower risk of incident dementia and is a promising target of intervention for cognitive health outcomes.

Parenting Programs for Disruptive Child Behavior in China: A Meta-Analysis and Systematic Review

2021 ◽  
pp. 104973152110185
Author(s):  
Ningxuan Hua ◽  
Patty Leijten
Keyword(s):  
Child Behavior ◽  
Meta Analysis ◽  
Behavioral Approach ◽  
Parenting Programs ◽  
Behavioral Management ◽  
Total N ◽  
Chinese Families ◽  
Inconsistent Parenting ◽  
Program Effects ◽  
Disruptive Child Behavior

Purpose: To synthesize evidence of parenting program effects on disruptive child behavior in China and compare three program approaches: behavioral, relational, and cognitive. Methods: We searched five databases (four English and one Chinese) and identified 45 studies; 29 studies were included in a multilevel meta-analysis (92 effect sizes; total N total = 3,892; M child age = 6.12 years). Results: We found large overall effects on reduced disruptive child behavior ( d = −1.28, 95% CI [−1.86, −0.70], p < .001), reduced harsh and inconsistent parenting ( d = −1.70, 95% CI [−2.91, −0.49], p <.001), and improved parental warmth and positive behavioral management ( d = 2.67, 95% CI [0.41, 4.93], p <.001). Behavioral programs were more effective than relational programs (Δ d = .89, 95% CI [−1.7, −0.13], p = .034), and cognitive programs were too rare to analyze separately. Conclusions: Parenting programs for disruptive child behavior can effectively support Chinese families, especially those adopting a behavioral approach.

scholarly journals Major Adverse Cardiac Events and Mortality Associated with Electroconvulsive Therapy

2019 ◽  
Vol 130 (1) ◽  
pp. 83-91 ◽  
Author(s):  
Andreas Duma ◽  
Mathias Maleczek ◽  
Basil Panjikaran ◽  
Harald Herkner ◽  
Theodore Karrison ◽  
...  
Keyword(s):  
Heart Failure ◽  
Pulmonary Edema ◽  
Acute Heart Failure ◽  
Electroconvulsive Therapy ◽  
Meta Analysis ◽  
Incidence Rates ◽  
Major Adverse Cardiac Events ◽  
Cardiac Events ◽  
Total N ◽  
Adverse Cardiac Events

Abstract EDITOR’S PERSPECTIVE What We Already Know about This Topic The incidence of major adverse cardiac events after electroconvulsive therapy is not known What This Article Tells Us That Is New Major adverse cardiac events and death after electroconvulsive therapy are infrequent and occur in about 1 of 50 patients and after about 1 of 200 to 500 electroconvulsive therapy treatments Background Cardiac events after electroconvulsive therapy have been reported sporadically, but a systematic assessment of the risk is missing. The goal of this study was to obtain a robust estimate of the incidence of major adverse cardiac events in adult patients undergoing electroconvulsive therapy. Methods Systematic review and meta-analysis of studies that investigated electroconvulsive therapy and reported major adverse cardiac events and/or mortality. Endpoints were incidence rates of major adverse cardiac events, including myocardial infarction, arrhythmia, pulmonary edema, pulmonary embolism, acute heart failure, and cardiac arrest. Additional endpoints were all-cause and cardiac mortality. The pooled estimated incidence rates and 95% CIs of individual major adverse cardiac events and mortality per 1,000 patients and per 1,000 electroconvulsive therapy treatments were calculated. Results After screening of 2,641 publications and full-text assessment of 284 studies, the data of 82 studies were extracted (total n = 106,569 patients; n = 786,995 electroconvulsive therapy treatments). The most commonly reported major adverse cardiac events were acute heart failure, arrhythmia, and acute pulmonary edema with an incidence (95% CI) of 24 (12.48 to 46.13), 25.83 (14.83 to 45.00), and 4.92 (0.85 to 28.60) per 1,000 patients or 2.44 (1.27 to 4.69), 4.66 (2.15 to 10.09), and 1.50 (0.71 to 3.14) per 1,000 electroconvulsive therapy treatments. All-cause mortality was 0.42 (0.11 to 1.52) deaths per 1,000 patients and 0.06 (0.02 to 0.23) deaths per 1,000 electroconvulsive therapy treatments. Cardiac death accounted for 29% (23 of 79) of deaths. Conclusions Major adverse cardiac events and death after electroconvulsive therapy are infrequent and occur in about 1 of 50 patients and after about 1 of 200 to 500 electroconvulsive therapy treatments.

Mesenchymal stem cells immortalization's and state-of-art: a systematic review and meta-analysis

2021 ◽  
Vol 31 (Supplement_2) ◽  
Author(s):  
P E F Stricker ◽  
A C Irioda ◽  
B F Mogharbel ◽  
E Abdelwaid ◽  
L R Cavalli ◽  
...  
Keyword(s):  
Stem Cells ◽  
Mesenchymal Stem Cells ◽  
Gene Transfection ◽  
Meta Analysis ◽  
Total N ◽  
Htert Gene ◽  
Cell Immortalization ◽  
Immortalized Cell ◽  
Experimental Strategies ◽  
Established Technique

Abstract Background The immortalization of mesenchymal stem cells (MSCs) allows them to avoid senescence and be cultured through limitless cell passages. Thus, several experimental strategies, such as retrovirus-mediated gene transfer or viral oncogenesis, have been applied for the immortalization of MSCs. The aim was to identifier the most commonly used methodologies and their particularities for the immortalization of human and animal MSCs. Methods The search was conducted in June 2019 and developed in SCOPUS, PUBMED, and SCIENCE DIRECT. Statistical analysis was performed, obtaining the values of total n, mean and standard deviation, confidence interval (CI), and percentage (frequency) for all the predictors. Results The most used immortalization methodology was viral transfection, being the most common immortalized cell type was the bone marrow-derived MSC, and the most used gene for immortalizing both human and animal MSCs was hTERT (39.3%) and SV40T (54.5%). Among the articles analyzed in this review, only 39.3% and 36.4% of human and animal MSCs immortalization protocols, respectively, underwent the tumorigenicity test. Conclusions The virus-mediated gene transfection was observed as the most used and established technique. The insertion of the hTERT gene is still the most used gene for cell immortalization, suggesting that the maintenance of telomerase is efficient for maintaining cell proliferation and bypassing cell senescence. The review concluded that the tumorigenicity tests should become mandatory in order to safely use the immortalized MSCs for translation.

scholarly journals Simulation of nitrogen deposition in the North China Plain by the FRAME model

2011 ◽  
Vol 8 (11) ◽  
pp. 3319-3329 ◽  
Author(s):  
Y. Zhang ◽  
A. J. Dore ◽  
X. Liu ◽  
F. Zhang
Keyword(s):  
North China Plain ◽  
North China ◽  
Terrestrial Ecosystem ◽  
N Deposition ◽  
The Yellow Sea ◽  
Natural Ecosystems ◽  
Total N ◽  
Frame Model ◽  
The North ◽  
The North China Plain

Abstract. Simulation of atmospheric nitrogen (N) deposition in the North China Plain (NCP) at high resolution, 5 × 5 km2, was conducted for the first time by the Fine Resolution Atmospheric Multi-pollutant Exchange (FRAME) model. The total N deposition budget was 1481 Gg in this region, with 77 % from reduced N and 23 % from oxidized N, and the annual deposition rate (47 kg N ha−1) was much higher than previously reported values for other parts of the world such as the UK (13 kg N ha−1), Poland (7.3 kg N ha−1) and EU27 (8.6 kg N ha−1). The exported N component (1981 Gg) was much higher than the imported N component (584 Gg), suggesting that the NCP is an important net emission source of N pollutants. Contributions of N deposition budgets from the seven provinces in this region were proportional to their area ratios. The calculated spatial distributions of N deposition displayed high rates of reduced N deposition in the south and of oxidized N deposition in the eastern part. The N deposition exceeded an upper limit of 30 kg N ha−1 for natural ecosystems over more than 90 % of the region, resulting in terrestrial ecosystem deterioration, impaired air quality and coastal eutrophication not only in the NCP itself but also in surrounding areas including the Bohai Sea and the Yellow Sea.

scholarly journals Outcomes of Long-Term Conservation Tillage Research in Northern China

2020 ◽  
Vol 12 (3) ◽  
pp. 1062 ◽  
Author(s):  
Francis Azumah Chimsah ◽  
Liqun Cai ◽  
Jun Wu ◽  
Renzhi Zhang
Keyword(s):  
Crop Yields ◽  
Greenhouse Gas Emission ◽  
Conservation Tillage ◽  
Cropping Systems ◽  
Meta Analysis ◽  
Arable Land ◽  
Aggregate Stability ◽  
Northern China ◽  
Total N

Sustainable food production has long been a priority for mankind and this is being challenged by limited arable land, challenged landscapes, and higher human population growth. China started conservation farming around the 1950’s. However, main Conservation Tillage (CT) research started in 1992. Using a systematic meta-analysis approach, this review aims at examining China’s approach to CT and to characterize the main outcomes of long-term CT research across northern China. Data from organizations in charge of CT research in China showed an improvement in crop yield of at least 4% under double cropping systems and 6% under single cropping systems in dry areas of northern China. Furthermore, long-term CT practices were reported to have improved soil physical properties (soil structure, bulk density, pore size, and aggregate stability), soil nutrient levels, and reduction in greenhouse gas emission. Other benefits include significant increase in income levels and protection of the environment. Limitations to CT practice highlighted in this study include occasional reduction in crop yields during initial years of cropping, significant reduction in total N of soils, increase in N2O emission, and the need for customized machinery for its implementation. Outcomes of CT practice are ecologically and economically beneficial though its limitations are worth cogitating.

scholarly journals Exchange of reactive nitrogen compounds: concentrations and fluxes of total ammonium and total nitrate above a spruce forest canopy

2009 ◽  
Vol 6 (6) ◽  
pp. 10663-10706
Author(s):  
V. Wolff ◽  
I. Trebs ◽  
T. Foken ◽  
F. X. Meixner
Keyword(s):  
Forest Canopy ◽  
N Deposition ◽  
Reactive Nitrogen ◽  
Nitrogen Compounds ◽  
Spruce Forest ◽  
Gaseous Species ◽  
Total N ◽  
Fog Water ◽  
Dry Conditions ◽  
Total Ammonium

Abstract. Total ammonium (tot-NH4+) and total nitrate (tot-NO3−) provide a chemically conservative quantity in the measurement of exchange processes of reactive nitrogen compounds ammonia (NH3), particulate ammonium (NH4+), nitric acid (HNO3), and particulate nitrate (NO3−), using the aerodynamic gradient method. Total fluxes were derived from concentration differences of total ammonium (NH3 and NH4+) and total nitrate (HNO3 and NO3−) measured at two levels. Gaseous species and related particulate compounds were measured selectively, simultaneously and continuously above a spruce forest canopy in south-eastern Germany in summer 2007. Measurements were performed using a wet-chemical two-point gradient instrument, the GRAEGOR. Median concentrations of NH3, HNO3, NH4−, and NO3− were 0.57, 0.12, 0.76, and 0.48 μg m−3, respectively. Total ammonium and total nitrate fluxes showed large variations depending on meteorological conditions, with concentrations close to zero under humid and cool conditions and higher concentrations under dry conditions. Mean fluxes of total ammonium and total nitrate in September 2007 were directed towards the forest canopy and were −65.77 ng m−2 s−1 and −41.02 ng m−2 s−1 (in terms of nitrogen), respectively. Their deposition was controlled by aerodynamic resistances only, with very little influence of surface resistances. Including measurements of wet deposition and findings of former studies at the study site on occult deposition (fog water interception), the total N deposition in September 2007 was estimated to 5.86 kg ha−1.

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