scholarly journals How do we construct and operate experimental streams? An overview of facilities, protocols, and studied questions

Hydrobiologia ◽  
2019 ◽  
Vol 847 (1) ◽  
pp. 1-10 ◽  
Author(s):  
Noémi Menczelesz ◽  
Ildikó Szivák ◽  
Dénes Schmera
Keyword(s):  
Statistical Power ◽  
Current Knowledge ◽  
Global Scale ◽  
Future Research ◽  
Future Studies ◽  
Natural Stream ◽  
Experimental Protocols ◽  
Organism Group ◽  
Experimental Stream ◽  
Over Time

Abstract Experimental streams are bounded and partly enclosed lotic units that facilitate the simulation of certain aspects of natural stream ecosystems under controlled conditions. We summarized the current knowledge regarding experimental streams in order to support researchers in designing and undertaking future studies using experimental streams. We observed an increase in the number of such studies since 1975. The geographically uneven distribution of studies suggests that the generalization of findings to global scale may not be straightforward. Our results indicate that macroinvertebrates, fish, and algae are the most frequently studied organisms and that the size of the experimental streams was related to the focal organism group(s) studied. The size of the units decreased over time, while the number of treatments, interpreted as the combination of the levels of factors, increased. These results suggest that biologically complex studies have gradually been replaced by biologically less complex ones. In contrast, the experimental complexity (the number of treatments) and the statistical power (number of replication) increased. Finally, we identified a number of important, but poorly documented pieces of information regarding experimental stream systems and experimental protocols and made recommendations for future research.

scholarly journals Role of microRNAs in Venous Thromboembolism

2020 ◽  
Vol 21 (7) ◽  
pp. 2602 ◽  
Author(s):  
Vânia M. Morelli ◽  
Sigrid K. Brækkan ◽  
John-Bjarne Hansen
Keyword(s):  
Venous Thromboembolism ◽  
Animal Models ◽  
Statistical Power ◽  
Current Knowledge ◽  
Thrombus Formation ◽  
Therapeutic Targets ◽  
Small Sample ◽  
Future Research ◽  
Gene Expressions

MicroRNAs (miRNAs) are non-coding RNAs that execute their function by targeted downregulation of gene expressions. There is growing evidence from epidemiological studies and animal models suggesting that the expression level of miRNAs is dysregulated in venous thromboembolism (VTE). In this review, we summarize the current knowledge on the role of miRNAs as biomarkers for VTE and provide general insight into research exploring the modulation of miRNA activity in animal models of venous thrombosis. Up to now, published studies have yielded inconsistent results on the role of miRNAs as biomarkers for VTE with most of the reports focused on diagnostic research. The limited statistical power of the individual studies, due to the small sample sizes, may substantially contribute to the poor reproducibility among studies. In animal models, over-expression or inhibition of some miRNAs appear to influence venous thrombus formation and resolution. However, there is an important gap in knowledge on the potential role of miRNAs as therapeutic targets in VTE. Future research involving large cohorts should be designed to clarify the clinical usefulness of miRNAs as biomarkers for VTE, and animal model studies should be pursued to unravel the role of miRNAs in the pathogenesis of VTE and their potential as therapeutic targets.

scholarly journals A Knowledge Management IT Tool: An Investigation within a Marketing Introductory Course

10.28945/3697 ◽  
2017 ◽  
Author(s):  
Samie Li Shang Ly ◽  
Raafat G Saade
Keyword(s):  
Knowledge Management ◽  
Knowledge Creation ◽  
Current Knowledge ◽  
Community Level ◽  
Future Research ◽  
Introductory Course ◽  
Repeated Practice ◽  
Common Goals ◽  
Shed Light ◽  
Over Time

Aim/Purpose: The purpose of this study is to shed light on how students learn within an environment tailored to knowledge creation. Background: We build on Nonaka, Toyama, and Konno’s three key elements: SECI model, Ba, Leadership as well as current knowledge management researchers critiques and improvements. Methodology: Based on an introductory marketing course, we used an in-house web based learning tool (peer-to peer) to capture score performances and perception surveys. The analysis was conducted through an exploratory factor analysis (EFA). Contribution: This study shed light on current knowledge management critiques by providing measures at the micro-level and community level. Findings: Perceptions of adaptability and usefulness change positively over time, while students’ repeated practice prepares them for different styles of questions as their performances increases over time. Recommendations for Practitioners: Organizations can understand how employees create knowledge through exchange of ideas, feedback, and common goals. Supervisor can understand their employees better and employees can gain a sense of control on their work. Recommendation for Researchers: The ability to capture information over time on the human and community level within a system allows further research to shed light on different variables of knowledge creation in the field. Impact on Society : An appreciation of the mechanism of knowledge creation can encourage organization to become more innovative and focus on people rather than material. Future Research: Measures such as the engagement level, the personality level, and compatibility level within a community to create knowledge are to be explored.

scholarly journals Review on basic income (BI): its theories and empirical cases

2021 ◽  
Author(s):  
Jiaqi Yang ◽  
Geetha Mohan ◽  
Supriya Pipil ◽  
Kensuke Fukushi
Keyword(s):  
Social Transformation ◽  
Social Economic ◽  
Current Knowledge ◽  
Future Research ◽  
Human Society ◽  
Basic Income ◽  
Future Studies ◽  
Fundamental Knowledge ◽  
Universal Principles ◽  
Important Solution

AbstractA basis of fundamental knowledge of different basic income approaches (BI) is essential to be elaborated for enhancing the prevalent debates on BI as an important solution on social transformation. Aiming to contribute to the current knowledge gaps and future research agendas on BI, this paper elaborates on BI theories and BI empirical cases, linkage, and gaps between these two parts. A total of 152 pieces of literature on BI theories and BI empirical cases were intensively reviewed, which includes BI definitions, positive and negative conceptual impacts of BI argued to bring to human society from social, economic, and policy-and-governance perspectives, as well as the implementation and the outcomes of 15 selected BI empirical cases. Our findings indicate that BI definitions remain imprecise, and the BI empirical cases are implemented in diverse ways. We also identified that many conceptual impacts of BI were not achieved in the reviewed BI empirical cases. We further argue that the policy environment for implementing BI has not been entirely created at present, and a key issue  is that the ambiguity between the BI theories and BI empirical cases causes difficulties to generate widely agreed principles guiding the implementation of BI. This paper suggests that future studies on BI should focus more on revising existing BI definitions which need to be simplified, detailed, and unified, generating universal principles guiding the implementation of BI, and developing indicators measuring BI's consequences.

scholarly journals Benthic estuarine communities in Brazil: moving forward to long term studies to assess climate change impacts

2016 ◽  
Vol 64 (spe2) ◽  
pp. 81-96 ◽  
Author(s):  
Angelo Fraga Bernardino ◽  
Paulo Roberto Pagliosa ◽  
Ronaldo Adriano Christofoletti ◽  
Francisco Barros ◽  
Sergio A. Netto ◽  
...  
Keyword(s):  
Climate Change ◽  
Human Activities ◽  
Current Knowledge ◽  
Global Scale ◽  
Current Data ◽  
Future Research ◽  
Mangrove Forests ◽  
Ecological Processes ◽  
Estuarine Ecosystems

Abstract Estuaries are unique coastal ecosystems that sustain and provide essential ecological services for mankind. Estuarine ecosystems include a variety of habitats with their own sediment-fauna dynamics, all of them globally undergoing alteration or threatened by human activities. Mangrove forests, saltmarshes, tidal flats and other confined estuarine systems are under increasing stress due to human activities leading to habitat and species loss. Combined changes in estuarine hydromorphology and in climate pose severe threats to estuarine ecosystems on a global scale. The ReBentos network is the first integrated attempt in Brazil to monitor estuarine changes in the long term to detect and assess the effects of global warming. This paper is an initial effort of ReBentos to review current knowledge on benthic estuarine ecology in Brazil. We herein present and synthesize all published work on Brazilian estuaries that has focused on the description of benthic communities and related ecological processes. We then use current data on Brazilian estuaries and present recommendations for future studies to address climate change effects, suggesting trends for possible future research and stressing the need for long-term datasets and international partnerships.

Mesophyll conductance: the leaf corridors for photosynthesis

2020 ◽  
Vol 48 (2) ◽  
pp. 429-439 ◽  
Author(s):  
Jorge Gago ◽  
Danilo M. Daloso ◽  
Marc Carriquí ◽  
Miquel Nadal ◽  
Melanie Morales ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Current Knowledge ◽  
Main Role ◽  
Mesophyll Conductance ◽  
Future Studies ◽  
Cell Structures ◽  
Leaf Tissues ◽  
Change Framework ◽  
Chloroplast Stroma

Besides stomata, the photosynthetic CO2 pathway also involves the transport of CO2 from the sub-stomatal air spaces inside to the carboxylation sites in the chloroplast stroma, where Rubisco is located. This pathway is far to be a simple and direct way, formed by series of consecutive barriers that the CO2 should cross to be finally assimilated in photosynthesis, known as the mesophyll conductance (gm). Therefore, the gm reflects the pathway through different air, water and biophysical barriers within the leaf tissues and cell structures. Currently, it is known that gm can impose the same level of limitation (or even higher depending of the conditions) to photosynthesis than the wider known stomata or biochemistry. In this mini-review, we are focused on each of the gm determinants to summarize the current knowledge on the mechanisms driving gm from anatomical to metabolic and biochemical perspectives. Special attention deserve the latest studies demonstrating the importance of the molecular mechanisms driving anatomical traits as cell wall and the chloroplast surface exposed to the mesophyll airspaces (Sc/S) that significantly constrain gm. However, even considering these recent discoveries, still is poorly understood the mechanisms about signaling pathways linking the environment a/biotic stressors with gm responses. Thus, considering the main role of gm as a major driver of the CO2 availability at the carboxylation sites, future studies into these aspects will help us to understand photosynthesis responses in a global change framework.

Power of Modified Brown-Forsythe and Mixed-Model Approaches in Split-Plot Designs

Methodology ◽  
2017 ◽  
Vol 13 (1) ◽  
pp. 9-22 ◽  
Author(s):  
Pablo Livacic-Rojas ◽  
Guillermo Vallejo ◽  
Paula Fernández ◽  
Ellián Tuero-Herrero
Keyword(s):  
Repeated Measures ◽  
Statistical Power ◽  
Mixed Model ◽  
Covariance Structure ◽  
Simulation Method ◽  
Future Research ◽  
Repeated Measures Design ◽  
Fixed And Random Effects ◽  
Split Plot ◽  
High Level

Abstract. Low precision of the inferences of data analyzed with univariate or multivariate models of the Analysis of Variance (ANOVA) in repeated-measures design is associated to the absence of normality distribution of data, nonspherical covariance structures and free variation of the variance and covariance, the lack of knowledge of the error structure underlying the data, and the wrong choice of covariance structure from different selectors. In this study, levels of statistical power presented the Modified Brown Forsythe (MBF) and two procedures with the Mixed-Model Approaches (the Akaike’s Criterion, the Correctly Identified Model [CIM]) are compared. The data were analyzed using Monte Carlo simulation method with the statistical package SAS 9.2, a split-plot design, and considering six manipulated variables. The results show that the procedures exhibit high statistical power levels for within and interactional effects, and moderate and low levels for the between-groups effects under the different conditions analyzed. For the latter, only the Modified Brown Forsythe shows high level of power mainly for groups with 30 cases and Unstructured (UN) and Autoregressive Heterogeneity (ARH) matrices. For this reason, we recommend using this procedure since it exhibits higher levels of power for all effects and does not require a matrix type that underlies the structure of the data. Future research needs to be done in order to compare the power with corrected selectors using single-level and multilevel designs for fixed and random effects.

The Limits of Ego Depletion

2019 ◽  
Vol 50 (5-6) ◽  
pp. 292-304 ◽  
Author(s):  
Mario Wenzel ◽  
Marina Lind ◽  
Zarah Rowland ◽  
Daniela Zahn ◽  
Thomas Kubiak
Keyword(s):  
Research Agenda ◽  
Statistical Power ◽  
Interindividual Variability ◽  
Ego Depletion ◽  
Crossover Design ◽  
Effect Sizes ◽  
Future Research ◽  
Future Research Agenda ◽  
Depletion Effect ◽  
Within Subjects

Abstract. Evidence on the existence of the ego depletion phenomena as well as the size of the effects and potential moderators and mediators are ambiguous. Building on a crossover design that enables superior statistical power within a single study, we investigated the robustness of the ego depletion effect between and within subjects and moderating and mediating influences of the ego depletion manipulation checks. Our results, based on a sample of 187 participants, demonstrated that (a) the between- and within-subject ego depletion effects only had negligible effect sizes and that there was (b) large interindividual variability that (c) could not be explained by differences in ego depletion manipulation checks. We discuss the implications of these results and outline a future research agenda.

Depressive Traits and Theory of Mind in Healthy Individuals: A Mediation Study

2018 ◽  
Author(s):  
Nicholas James Rowark
Keyword(s):  
Theory Of Mind ◽  
Executive Functions ◽  
Executive Control ◽  
Statistical Power ◽  
Social Cognitive ◽  
Clinical Sample ◽  
Small Sample ◽  
Future Research ◽  
Healthy Individuals ◽  
Prepotent Response

Depression has been associated with poor social cognitive functioning, including impaired performance on measures of theory of mind. However, the association between depression and theory of mind performance has been removed when controlling for differences in executive functioning, which is also impacted by depression. Among these executive functions, inhibition of prepotent response has been demonstrated as enabling success on theory of mind tests. In the context of these findings, the current investigation tested whether a relationship could be found between depressive traits and theory of mind in a non-clinical sample, and whether this relationship was mediated by differences in executive control of inhibition. Theory of mind was assessed in 31 healthy individuals using an audio-presented false-belief reasoning task, which also tested baseline performance in non-mental-state reasoning. Inhibition of prepotent response was assessed with interference measures on a Stroop colour-word task, and depressive traits were self-reported through the second version of the Beck Depression Inventory. Mediation analysis revealed that executive control of inhibition did not significantly mediate an indirect effect of depressive traits on theory of mind. It was interpreted that relationships previously found between major depression, executive and social-cognitive functions do not generalise beyond clinical boundaries. However, these findings are discussed in terms of the small sample size, limiting statistical power, and several methodological limitations. Future research should assess the relationship between depressive traits and theory of mind using alternative measures of mental representation, or include a neurocognitive battery assessing executive functions other than inhibition.

Plant Compounds for the Treatment of Diabetes, a Metabolic Disorder: NF-κB as a Therapeutic Target

2020 ◽  
Vol 26 (39) ◽  
pp. 4955-4969
Author(s):  
Ravi Sahukari ◽  
Jyothi Punabaka ◽  
Shanmugam Bhasha ◽  
Venkata S. Ganjikunta ◽  
Shanmugam K. Ramudu ◽  
...  
Keyword(s):  
Diabetic Complications ◽  
Current Knowledge ◽  
World Population ◽  
Future Studies ◽  
Expression Of Genes ◽  
Treatment Of Diabetes ◽  
Online Library ◽  
And Oxidative Stress ◽  
Stress Activation ◽  
Plant Compounds

Background: The prevalence of diabetes in the world population hás reached 8.8 % and is expected to rise to 10.4% by 2040. Hence, there is an urgent need for the discovery of drugs against therapeutic targets to sojourn its prevalence. Previous studies proved that NF-κB serves as a central agent in the development of diabetic complications. Objectives: This review intended to list the natural plant compounds that would act as inhibitors of NF-κB signalling in different organs under the diabetic condition with their possible mechanism of action. Methods: Information on NF-κB, diabetes, natural products, and relation in between them, was gathered from scientific literature databases such as Pubmed, Medline, Google scholar, Science Direct, Springer, Wiley online library. Results and Conclusion: NF-κB plays a crucial role in the development of diabetic complications because of its link in the expression of genes that are responsible for organs damage such as kidney, brain, eye, liver, heart, muscle, endothelium, adipose tissue and pancreas by inflammation, apoptosis and oxidative stress. Activation of PPAR-α, SIRT3/1, and FXR through many cascades by plant compounds such as terpenoids, iridoids, flavonoids, alkaloids, phenols, tannins, carbohydrates, and phytocannabinoids recovers diabetic complications. These compounds also exhibit the prevention of NF-κB translocation into the nucleus by inhibiting NF-κB activators, such as VEGFR, RAGE and TLR4 receptors, which in turn, prevent the activation of many genes involved in tissue damage. Current knowledge on the treatment of diabetes by targeting NF-κB is limited, so future studies would enlighten accordingly.

Amruthapala (Decalepis arayalpathra (J. Joseph and V. Chandras.) Venter): A Comprehensive Review on Diversity, Therapeutic Uses, and Valorization of Bioactive Constituents

2019 ◽  
Vol 20 (5) ◽  
pp. 376-389 ◽  
Author(s):  
Sonali Mishra ◽  
Nupur Srivastava ◽  
Velusamy Sundaresan ◽  
Karuna Shanker
Keyword(s):  
Secondary Metabolite ◽  
Current Knowledge ◽  
Experimental Studies ◽  
Critical Discussion ◽  
Future Research ◽  
Bioactive Constituents ◽  
Medicinal Uses ◽  
Comprehensive Review ◽  
Therapeutic Uses ◽  
Decalepis Arayalpathra

Background: Decalepis arayalpathra (J. Joseph and V. Chandras.) Venter is used primarily for nutrition besides its therapeutic values. Traditional preparations/formulations from its tuber are used as a vitalizer and blood purifier drink. The folklore medicinal uses cover inflammation, cough, wound healing, antipyretic, and digestive system management. A comprehensive review of the current understanding of the plant is required due to emerging concerns over its safety and efficacy. Objective: The systematic collection of the authentic information from different sources with the critical discussion is summarised in order to address various issues related to botanical identity, therapeutic medicine, nutritional usage, phytochemical, and pharmacological potentials of the D. arayalpathra. Current use of traditional systems of medicine can be used to expand future research opportunities. Materials and Methods: Available scripted information was collected manually, from peered review research papers and international databases viz. Science Direct, Google Scholar, SciFinder, Scopus, etc. The unpublished resources which were not available in database were collected through the classical books of ‘Ayurveda’ and ‘Siddha’ published in regional languages. The information from books, Ph.D. and MSc dissertations, conference papers and government reports were also collected. We thoroughly screened the scripted information of classical books, titles, abstracts, reports, and full-texts of the journals to establish the reliability of the content. Results: Tuber bearing vanilla like signature flavor is due to the presence of 2-hydroxy-4-methoxybenzaldehyde (HMB). Among five other species, Decalepis arayalpathra (DA) has come under the ‘critically endangered’ category, due to over-exploitation for traditional, therapeutic and cool drink use. The experimental studies proved that it possesses gastro-protective, anti-tumor, and antiinflammatory activities. Some efforts were also made to develop better therapeutics by logical modifications in 2-Hydroxy-4-methoxy-benzaldehyde, which is a major secondary metabolite of D. arayalpathra. ‘Amruthapala’ offers the enormous opportunity to develop herbal drink with health benefits like gastro-protective, anti-oxidant and anti-inflammatory actions. Results: The plant has the potential to generate the investigational new lead (IND) based on its major secondary metabolite i.e. 2-Hydroxy-4-methoxy-benzaldehyde. The present mini-review summarizes the current knowledge on Decalepis arayalpathra, covering its phytochemical diversity, biological potentials, strategies for its conservation, and intellectual property rights (IPR) status. Chemical Compounds: 2-hydroxy-4-methoxybenzaldehyde (Pubchem CID: 69600), α-amyrin acetate (Pubchem CID: 293754), Magnificol (Pubchem CID: 44575983), β-sitosterol (Pubchem CID: 222284), 3-hydroxy-p-anisaldehyde (Pubchem CID: 12127), Naringenin (Pubchem CID: 932), Kaempferol (Pubchem CID: 5280863), Aromadendrin (Pubchem CID: 122850), 3-methoxy-1,2-cyclopentanedione (Pubchem CID: 61209), p-anisaldehyde (Pubchem CID: 31244), Menthyl acetate (Pubchem CID: 27867), Benzaldehyde (Pubchem CID: 240), p-cymene (Pubchem CID: 7463), Salicylaldehyde (Pubchem CID: 6998), 10-epi-γ-eudesmol (Pubchem CID: 6430754), α -amyrin (Pubchem CID: 225688), 3-hydroxy-4-methoxy benzaldehyde (Pubchem CID: 12127).

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