Hiding resonant planets behind a big friend

2020 ◽  
Author(s):  
Laetitia Rodet ◽  
Dong Lai
Keyword(s):  
Theoretical Study ◽  
Giant Planet ◽  
Relative Strength ◽  
Indirect Detection ◽  
Mean Motion ◽  
Formation And Evolution ◽  
The Impact ◽  
Mean Motion Resonance

<p class="western" align="justify">The characterization of the interplay between the inner and outer parts of planetary systems has long been impractical due to the separated detection ranges of the corresponding observation techniques. However, this gap is closing thanks to the technical improvements of the instruments and the longer observational baselines, and statistical insights are already within reach on the impact of cold Jupiters on super Earths. In this talk, I would like to present a theoretical study on the influence of an external giant planet misaligned with inner resonant planets, within the circular restricted problem. The behavior of the system depends on the relative strength between the coupling of the planets and the perturbations from the outer body. We demonstrated that mean-motion resonance strengthens the inner coupling and is very resilient to the perturbation, surviving periodic relative inclination increases of tens of degrees between the inner planets. This study has applications for the indirect detection of exoplanets, as well as the understanding of their formation and evolution, in particular the role of mean-motion resonance and relative inclinations.</p>

scholarly journals Adolescents’ Intuitive Appraisal, Attributions and Emotions for their Relationships with their Parents

2012 ◽  
Vol 2 (6) ◽  
pp. 22
Author(s):  
Georgia Stephanou ◽  
Georgios Gkavras
Keyword(s):  
Relative Strength ◽  
Related Factors ◽  
Parent Relationships ◽  
General Outcome ◽  
Controllable Factors ◽  
Adolescent Parent ◽  
Parent Relationship ◽  
The Impact ◽  
The Relationship

This study study aimed to examine (a) adolescents’ attributions and emotions for their subjectively perceived good and bad relationships with their parents, (b) the association of the intuitive and attributional appraisals of the adolescent-parent relationship with the subsequent emotions, and (c) the role of the perceived importance of the good adolescent-parent relationship in the generation of attributions and emotions, and in the impact of attributions on emotions. The sample comprised 670 adolescents, both genders, aged 14-17 years old, representing various parental socioeconomic levels. The results showed that: (a) It was extremely important for the adolescents to have good relationships with their parents, (b) the perceived good adolescent-parent relationships were attributed to internal, stable and personal controllable factors, along with parent- and self-parent interactive- related factors, while the estimated as bad relationships were attributed to external, stable, personal uncontrollable and external controllable factors (parents’ negative properties), (c) the adolescents experienced intense positive and negative emotions (mainly, general / outcome- dependent) for the perceived good and bad relationships with their parents, respectively, (d) both intuitive and attributional appraisals of the relationship were associated with the emotions, particularly in the perceived bad adolescent-parent relationship, and (e) the relative strength of the association of the attributional dimensions with the emotions varied between the perceived good and bad adolescent-parent relationship and across the various emotions. Keywords: Adolescent-Parent Relationship, Attributions, Emotions, Intuitive Appraisal.

Conceptual Framework for Non-Algorithmic Education in STEAM Education

2017 ◽  
pp. 178-195
Author(s):  
Marina Morari
Keyword(s):  
Conceptual Framework ◽  
Theoretical Study ◽  
Spiritual Intelligence ◽  
Knowledge Development ◽  
Learning Design ◽  
Methodological Research ◽  
Steam Education ◽  
The Impact ◽  
Psychological Dimensions

This chapter is based on a theoretical study of reflexivity, as a non-algorithmic method for Science, Technology, Engineering, Art, and Mathematic (STEAM Education). It explores the key shift in artistic education, embracing the role of scientific and artistic knowledge, knowledge development as an inner experience, importance of art for spiritual intelligence, as well as the philosophical and psychological dimensions of metacognition (as thinking about thinking). The focus in this chapter is related on understanding the complexity of reflexivity and the impact of metacognition within development of the artistic competence. Finally, the methodological research provides a conceptual framework that is important for learning design of non-algorithmic education.

scholarly journals Peritoneal Microbiome in End-Stage Renal Disease Patients and the Impact of Peritoneal Dialysis Therapy

2020 ◽  
Vol 8 (2) ◽  
pp. 173
Author(s):  
Liliana Simões-Silva ◽  
Ricardo Araujo ◽  
Manuel Pestana ◽  
Isabel Soares-Silva ◽  
Benedita Sampaio-Maia
Keyword(s):  
Peritoneal Dialysis ◽  
Human Microbiome ◽  
Cross Sectional Study ◽  
Cross Sectional ◽  
Peritoneal Tissue ◽  
Stage Renal Disease ◽  
End Stage ◽  
The Impact

Factors influencing the occurrence of peritoneal dialysis (PD)-related infections are still far from fully understood. Recent studies described the existence of specific microbiomes in body sites previously considered microbiome-free, unravelling new microbial pathways in the human body. In the present study, we analyzed the peritoneum of end-stage kidney disease (ESKD) patients to determine if they harbored a specific microbiome and if it is altered in patients on PD therapy. We conducted a cross-sectional study where the peritoneal microbiomes from ESKD patients with intact peritoneal cavities (ESKD non-PD, n = 11) and ESKD patients undergoing PD therapy (ESKD PD, n = 9) were analyzed with a 16S rRNA approach. Peritoneal tissue of ESKD patients contained characteristically low-abundance microbiomes dominated by Proteobacteria, Firmicutes, Actinobacteria, and Bacteroidetes. Patients undergoing PD therapy presented lower species richness, with dominance by the Pseudomonadaceae and Prevotelaceae families. This study provides the first characterization of the peritoneal microbiome in ESKD patients, bringing new insight to the human microbiome. Additionally, PD therapy may induce changes in this unique microbiome. The clinical relevance of these observations should be further explored to uncover the role of the peritoneal microbiome as a key element in the onset or aggravation of infection in ESKD patients, especially those undergoing PD.

Generation and Characterization Of a CD30 Positive T-Cell Lymphoma Mouse Model Resembling Human Anaplastic Large Cell Lymphoma

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 2450-2450
Author(s):  
Cathrin Klingeberg ◽  
Anna Lena Illert ◽  
Nicolas Schneider ◽  
Christian Peschel ◽  
Cornelius Miething ◽  
...  
Keyword(s):  
Bone Marrow ◽  
T Cells ◽  
T Cell ◽  
Large Cell ◽  
Cre Recombinase ◽  
Double Negative ◽  
Ki 67 ◽  
The Impact

Abstract Anaplastic large cell lymphomas (ALCL) are a subgroup of aggressive Non-Hodgkin-Lymphomas mainly affecting children and young adults. In 60 % of systemic ALCLs, a translocation t(2;5) (p23;q35) resulting in NPM-ALK fusion gene expression is found. The constitutively activation of ALK tyrosine kinase expressed from the NPM-promoter causes increased proliferation and inhibition of apoptosis thereby promoting cell survival and tumorigenesis. Immunphenotypic characterization of human ALCLs revealed highly CD30-positive cells of T- or Null-Cell-origin and resulted in promising clinical trials with CD30-coupled antibodies. However, the impact of CD30 on diseases development as well as NPM-ALK signal transduction in course of disease remains unclear and appropriate mouse models to answer these questions are missing. In this regard, we established a retroviral murine bone marrow (BM) transplantation model resembling a human ALCL-like T-cell neoplasia. Therefore we use an inducible Cre/loxP system where NPM-ALK expression is controlled and expressed in a special type of early T-cells. For generation of this vector, we inserted a floxed translational ‘stop-cassette’ between the retroviral promoter MSCV-LTR and the NPM-ALK cDNA, which guaranties specific expression of NPM-ALK only in cells, where the enzyme Cre-recombinase is expressed. Recognition of the loxP-sites by Cre-recombinase leads in our system to deletion of the stop-cassette and consequently NPM-ALK expression. Using different Cre-expressing cell types allowed us to study pathogenesis of ALCL in more detail. In our recent study, we infected bone marrow of transgenic mice expressing Cre-recombinase under the control of the Lck-promotor with our MSCV-Stop-NPM-ALK-IRES-EGFP (MSNAIE) vector and transplanted it into lethally irradiated C57Bl6 recipient mice. With a latency of 4-5 months, these mice developed Thy1.2-positive lymphomas and died from neoplastic infiltration of bone marrow and lymphatic organs with T-cells. Immunphenotypic analyses confirmed T-Cell origin of the lymphomas and showed importantly highly CD30-expression. Staining of the different T-cell-subpopulations demonstrated highest NPM-ALK expression in immature CD4/CD8 double negative T-cells and not fully differentiated CD4/CD8 double positive T-cells. Interestingly, FACS-staining of the proliferation marker Ki-67 revealed highest expression in CD4/CD8 double negative T-cells, in contrast to the other subpopulations where Ki-67 is less detected. Therefore we hypothesized, that the lymphoma initiating cell (LIC) must be within this early T-cell population. Most interestingly we found highest CD30-expression just in the same CD4/CD8 negative T-cell population, pointing to a crucial role of CD30 in lymphoma initiation. To further substantiate our hypothesis we performed secondary and tertiary transplantations with different sorted T-Cell subpopulation and indeed, the immature CD4/CD8 double negative population was able to initiate lymphoma growth in recipient mice. Further transplantations by limited dilution will help to identify the leukemia initiating cell in this model. Taken together, our murine LckCre-NPM-ALK bone marrow transplantation model represents a precise and versatile tool to study disease initiation and development resembling human ALCL. Moreover, the impact of specific proteins (e.g. CD30) in the course of disease can be addressed by combining Knockout (e.g. CD30)/LckCre transgenic mice with our model. To this end we crossed CD30/Lck-Cre mice, and preliminary analysis indicate that CD30 expression seems not to be required for the initial onset of disease. Further characterization of the role of CD30 in ALCL is ongoing. Disclosures: No relevant conflicts of interest to declare.

Ice Gouge Reliability of Offshore Arctic Pipelines

2007 ◽  
Author(s):  
A. H. Younan ◽  
J. M. Hamilton ◽  
J. Weaver
Keyword(s):  
Traditional Approach ◽  
Relative Strength ◽  
First Year ◽  
Burial Depth ◽  
Buried Pipe ◽  
Element Analysis ◽  
Statistical Characterization ◽  
The Impact ◽  
Adequate Reliability

Offshore arctic pipelines must be designed with adequate reliability against damage or rupture due to the effects of ice features that gouge the seafloor. A common design approach is to bury the pipeline sufficiently deep to avoid contact by a gouging ice keel of a target rare return interval. The effects of sub-gouge soil displacements on pipe stress or strain are also assessed. It is implicitly assumed, in this traditional approach, that ice keels have infinite strength and momentum, so that gouge depths are not limited by ice keel failure and direct contact of ice on pipe results in rupture. However, many first-year ice features may not be strong enough to gouge the soil to the extreme gouge depths. Considering the high cost of incremental pipeline burial depth, it may be desirable to account for limits imposed on extreme gouge depth by soil resistance. Introducing these limits, however, gives rise to additional uncertainty and requires the development of a reliability framework to assess the consequences of direct ice contact on the buried pipe. This paper presents a methodology for evaluating the probability of ice gouging non-performance of a pipeline while explicitly accounting for the ability of the seabed soil to limit ice gouge depth based on the relative strength of soil and ice keel. Non-performance is defined either as ice contact on the pipe or exceedence of some level of acceptable pipe strain when contacted by ice. A three-step approach is followed through the use of nonlinear finite element analysis to estimate pipeline capacity, the statistical characterization of demand from ice gouging events, and the development of a reliability framework combining demand and capacity. Parameters governing the capacity of the pipeline are identified, the sensitivity of the pipeline reliability to various parameters is investigated, and the impact of allowing ice contact on pipeline reliability is presented. Relative merits and risks of allowing ice contact are discussed in the context of pipeline reliability. The presented results and discussions are believed to be of significant help in the development of burial depth criteria for future offshore arctic pipelines, and certainly in the reassessment of existing ones.

scholarly journals Education and Politics in Africa

2020 ◽  
pp. 71-81
Author(s):  
Valentina Gribanova
Keyword(s):  
Negative Impact ◽  
Current Status ◽  
Educational Systems ◽  
African Countries ◽  
Boko Haram ◽  
Terrorist Organizations ◽  
Military Conflicts ◽  
The Impact

The article is devoted to the characterization of the models and the stages of formation of education systems in African countries and of their current status. The aim of the work was to analyze the impact of various factors on the development of education in Africa. In particular, the impact of military conflicts and the activities of terrorist organizations on the field of education were investigated. It also analyzes the increasing role of the world community in the development of education in African countries in recent decades. The main examples are the aspects of the activities of the terrorist organization Boko Haram, aimed at destabilizing and directly destroying the education system of Nigeria, and the impact of the Mali conflict of 2012-2013 on education. The activities of Boko Haram are widely covered in the scientific literature, but the article focuses on its aspects that are connected precisely with the negative impact on the educational system in Nigeria. The work broadens the perception of the challenges currently facing educational systems in Africa.

scholarly journals Measurement report: Effects of photochemical aging on the formation and evolution of summertime secondary aerosol in Beijing

2020 ◽  
Author(s):  
Tianzeng Chen ◽  
Jun Liu ◽  
Qingxin Ma ◽  
Biwu Chu ◽  
Peng Zhang ◽  
...  
Keyword(s):  
Chemical Characterization ◽  
Exposure Dose ◽  
Time Resolved ◽  
Increase Rate ◽  
Key Factor ◽  
Formation And Evolution ◽  
Photochemical Aging ◽  
Observation Period

Abstract. Atmospheric submicron aerosols have a great effect on air quality and human health, while their formation and evolution processes are still not fully understood. Herein, the crucial role of atmospheric oxidation capacity, as characterized by OH exposure dose in the formation and evolution of secondary submicron aerosols, was systematically investigated based on a highly time-resolved chemical characterization of PM1 in a southern suburb of Beijing in summertime from 25th July to 21st August 2019. The averaged concentration of PM1 was 19.3 ± 11.3 μg m−3, and nearly half (48.3 %) of the mass was organic aerosols (OA) during the observation period. The equivalent photochemical age (ta) estimated from the ratios of toluene to benzene was applied to characterize the OH exposure dose of the air mass. The relationships of NR–PM1 species, OA factors (i.e., one hydrocarbon-like (HOA) and three oxygenated (LO-OOA, SV-OOA and MO-OOA) organic aerosol factors) and elemental compositions (e.g., H / C, O / C, N / C, S / C, OM / OC, and OSc) to ta were analyzed in detail. It was found that higher PM1 concentration accompanied longer ta, with an average increase rate of 0.8 μg m−3 per hour. Meanwhile, the formation of SO42− and MO-OOA were most sensitive to the increase in ta, and their contributions to PM1 were enhanced from 19 % to 27 % and from 27 % to 48 %, respectively, as ta increased from 9.4 h to 19.6 h. In addition, OSc and the ratios of O / C and OM / OC increased with the increase in ta. These results indicated that photochemical aging is a key factor leading to the evolution of OA and the increase of PM1 in summertime.

scholarly journals Gap19, a Cx43 Hemichannel Inhibitor, Acts as a Gating Modifier That Decreases Main State Opening While Increasing Substate Gating

2020 ◽  
Vol 21 (19) ◽  
pp. 7340
Author(s):  
Alessio Lissoni ◽  
Nan Wang ◽  
Timur Nezlobinskii ◽  
Maarten De Smet ◽  
Alexander V. Panfilov ◽  
...  
Keyword(s):  
Kinetic Studies ◽  
Open Probability ◽  
Transition Analysis ◽  
Transmembrane Pores ◽  
Gating Modifier ◽  
Conductance States ◽  
Multiple Conductance States ◽  
The Impact

Cx43 hemichannels (HCs) are electrically and chemically gated transmembrane pores with low open probability and multiple conductance states, which makes kinetic studies of channel gating in large datasets challenging. Here, we developed open access software, named HemiGUI, to analyze HC gating transitions and investigated voltage-induced HC opening based on up to ≈4000 events recorded in HeLa-Cx43-overexpressing cells. We performed a detailed characterization of Cx43 HC gating profiles and specifically focused on the role of the C-terminal tail (CT) domain by recording the impact of adding an EGFP tag to the Cx43 CT end (Cx43-EGFP) or by supplying the Cx43 HC-inhibiting peptide Gap19 that interferes with CT interaction with the cytoplasmic loop (CL). We found that Gap19 not only decreased HC opening activity to the open state (≈217 pS) but also increased the propensity of subconductance (≈80 pS) transitions that additionally became slower as compared to the control. The work demonstrates that large sample transition analysis allows detailed investigations on Cx43 HC gating and shows that Gap19 acts as a HC gating modifier by interacting with the CT that forms a crucial gating element.

Exploring the Origin and Evolution of the Kepler 36 System

2020 ◽  
Author(s):  
Thomas Rimlinger ◽  
Douglas Hamilton
Keyword(s):  
Planetary System ◽  
Giant Planet ◽  
Period Ratio ◽  
Origin And Evolution ◽  
Mean Motion ◽  
Mean Motion Resonance

Abstract We examine the origins of the Kepler 36 planetary system, which features two very different planets: Kepler 36b, ($\rm \rho = 7.46$  $\rm g$  $\rm cm^{-3}$) and Kepler 36c ($\rm \rho = 0.89$  $\rm g$  $\rm cm^{-3}$). The planets lie extremely close to one another, separated by just 0.01 AU, and they orbit just a tenth of an AU from the host star. In our origin scenario, Kepler 36b starts with far less mass than Kepler 36c, a gaseous giant planet that forms outside the ice line and quickly migrates inward, capturing its neighbour into its 2:1 mean-motion resonance while continuing to move inward through a swarm of planetesimals and protoplanets. Subsequent collisions with these smaller bodies knock Kepler 36b out of resonance and raise its mass and density (via self-compression). We find that our scenario can yield planets whose period ratio matches that of Kepler 36b and c, although these successes are rare, occurring in just 1.2 per cent of cases. However, since systems like Kepler 36 are themselves rare, this is not necessarily a drawback.

scholarly journals Root volatiles in plant-plant interactions I: Characterization of root sesquiterpene emissions from Centaurea stoebe and their effects on other plants

2018 ◽  
Author(s):  
Valentin Gfeller ◽  
Meret Huber ◽  
Christiane Förster ◽  
Wei Huang ◽  
Tobias G. Köllner ◽  
...  
Keyword(s):  
Spotted Knapweed ◽  
Plant Interactions ◽  
Centaurea Stoebe ◽  
Positive Effects ◽  
Root Volatiles ◽  
The Impact ◽  
Germination And Growth ◽  
Plant Plant

AbstractVolatile organic compounds (VOCs) emitted by plant leaves can influence the physiology of neighboring plants. In contrast to interactions above ground, little is known about the role of VOCs in belowground plant-plant interactions. Here, we characterize constitutive root volatile emissions of the spotted knapweed (Centaurea stoebe) and explore the impact of these volatiles on the germination and growth of different sympatric plant species. We show that C. stoebe roots emit high amounts of sesquiterpenes, with estimated release rates of (E)-β-caryophyllene above 3 μg g−1 dw h−1. Sesquiterpene emissions show little variation between different C. stoebe populations, but vary substantially between different Centaurea species. Through root transcriptome sequencing, we identify six root-expressed sesquiterpene synthases (TPSs). Two root-specific TPSs, CsTPS4 and CsTPS5, are sufficient to produce the full blend of emitted root sesquiterpenes. Volatile exposure experiments demonstrate that C. stoebe root volatiles have neutral to positive effects on the germination and growth of different sympatric neighbors. Thus, constitutive root sesquiterpenes produced by two C. stoebe TPSs are associated with facilitation of sympatric neighboring plants. The release of root VOCs may thus influence C. stoebe abundance and plant community structure in nature.

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