scholarly journals Repeated replacement of an intrabacterial symbiont in the tripartite nested mealybug symbiosis

2016 ◽  
Author(s):  
Filip Husnik ◽  
John P McCutcheon
Keyword(s):  
Host Cell ◽  
Single Infection ◽  
Planococcus Citri ◽  
Evolutionary Time ◽  
Genomic Complexity ◽  
Gene Sets ◽  
The Face ◽  
Bacterial Endosymbionts ◽  
The Stability ◽  
Symbiont Genome

Stable endosymbiosis of a bacterium into a host cell promotes cellular and genomic complexity. The mealybug Planococcus citri has two bacterial endosymbionts; remarkably, the gammaproteobacterium Moranella endobia lives in the cytoplasm of the betaproteobacterium Tremblaya princeps. These two bacteria, along with genes horizontally transferred from other bacteria to the P. citri genome, encode complementary gene sets that form a complex metabolic patchwork. Here we test the stability of this three-way symbiosis by sequencing host-symbiont genome pairs for five diverse mealybug species. We find marked fluidity over evolutionary time: while Tremblaya is the result of a single infection in the ancestor of mealybugs, the innermost gammaproteobacterial symbionts result from multiple replacements of inferred different ages from related but distinct bacterial lineages. Our data show that symbiont replacement can happen even in the most intricate symbiotic arrangements, and that pre-existing horizontally transferred genes can remain stable on genomes in the face of extensive symbiont turnover.

scholarly journals Repeated replacement of an intrabacterial symbiont in the tripartite nested mealybug symbiosis

2016 ◽  
Vol 113 (37) ◽  
pp. E5416-E5424 ◽  
Author(s):  
Filip Husnik ◽  
John P. McCutcheon
Keyword(s):  
Host Cell ◽  
Single Infection ◽  
Planococcus Citri ◽  
Evolutionary Time ◽  
Genomic Complexity ◽  
Gene Sets ◽  
The Face ◽  
Bacterial Endosymbionts ◽  
Encode Gene ◽  
The Stability

Stable endosymbiosis of a bacterium into a host cell promotes cellular and genomic complexity. The mealybugPlanococcus citrihas two bacterial endosymbionts with an unusual nested arrangement: the γ-proteobacteriumMoranella endobialives in the cytoplasm of the β-proteobacteriumTremblaya princeps. These two bacteria, along with genes horizontally transferred from other bacteria to theP. citrigenome, encode gene sets that form an interdependent metabolic patchwork. Here, we test the stability of this three-way symbiosis by sequencing host and symbiont genomes for five diverse mealybug species and find marked fluidity over evolutionary time. AlthoughTremblayais the result of a single infection in the ancestor of mealybugs, the γ-proteobacterial symbionts result from multiple replacements of inferred different ages from related but distinct bacterial lineages. Our data show that symbiont replacement can happen even in the most intricate symbiotic arrangements and that preexisting horizontally transferred genes can remain stable on genomes in the face of extensive symbiont turnover.

Em transe-to

2020 ◽  
Vol 2 (1) ◽  
pp. 32-55
Author(s):  
Natalia Christofoletti Barrenha
Keyword(s):  
The Face ◽  
The Stability ◽  
The City

This text seeks to explore the Argentine films Castro (Alejo Moguillansky, 2009) and El asaltante (Pablo Fendrik, 2007) from within the displacement of their characters through the city. This transit configures the organising element of the plots, determining the direction and rhythm of events. The escape motto will structure the film analyses, which are also twinned by the sensory apprehension that comes from the spaces they travel through. The notion of escape, as explored by Esteban Dipaola in Argentine cinema of the 1990s, continues to throb in mid-to-late 2000s production, and in these films represents the means by which the protagonists deploy critical attitudes—sometimes radical and explosive, sometimes silent—in the face of fixed notions, suggesting some scepticism about the “stability” and “order” that they (dis)encounter in normality. RESUMEN Este texto busca explorar los largometrajes argentinos Castro (Alejo Moguillansky, 2009) y El asaltante (Pablo Fendrik, 2007) a partir del desplazamiento de sus personajes por la ciudad. El transitar se configura como elemento organizador de las tramas, determinando la dirección y el ritmo de los acontecimientos. El tema de la fuga irá estructurando los análisis de las películas, las cuales también están relacionadas por la aprehensión sensorial que hacen de los espacios que recorren. La noción de fuga, tal y como fue explorada por Esteban Dipaola en el cine argentino de los años 90, continúa vigente en la producción de mediados/fines de la primera década del siglo XXI, y en estas películas es el recurso por medio del cual los protagonistas despliegan actitudes críticas – a veces radicales y explosivas, y a veces silenciosas – frente a nociones convencionales, lo cual hace pensar que existe un cierto escepticismo con relación a la “estabilidad” y al “orden” que ellos (des)encuentran en la normalidad. RESUMO Este texto busca explorar os longas-metragens argentinos Castro (Alejo Moguillansky, 2009) e El asaltante (Pablo Fendrik, 2007) a partir do deslocamento de seus personagens pela cidade. O transitar configura-se como elemento organizador das tramas, determinando a direção e o ritmo dos acontecimentos. O mote da fuga estruturará as análises dos filmes, os quais também se irmanam pela apreensão sensorial que fazem dos espaços que percorrem. A noção de fuga, conforme explorada por Esteban Dipaola no cinema argentino da década de 1990, continua a pulsar na produção de meados/fins dos anos 2000, e é, nestes filmes, o recurso através do qual os protagonistas desdobram atitudes críticas – às vezes radicais e explosivas, às vezes silenciosas – diante de noções fixas, sugerindo certo ceticismo em relação à “estabilidade” e à “ordem” que eles (des)encontram na normalidade.

scholarly journals Study on instability failure mode and monitoring early warning standard of surrounding rock in fully weathered argillaceous sandstone section of large section tunnel

2019 ◽  
Vol 136 ◽  
pp. 04023
Author(s):  
Ming Zhao ◽  
Ke Li ◽  
Hong Yan Guo ◽  
KaiCheng Hua
Keyword(s):  
Limit State ◽  
Stable State ◽  
Simulation Software ◽  
Surrounding Rock ◽  
Large Section ◽  
Rock Stability ◽  
Geological Conditions ◽  
Construction Step ◽  
The Face ◽  
The Stability

Based on the special geological conditions of a tunnel in Qingyuan section of Huizhou-Zhanzhou Expressway, FLAC3d numerical simulation software is used to simulate the rheological properties and instability of surrounding rock in large-section fully weathered sandstone section, and the stability and loss of surrounding rock are analyzed. The deformation of the dome and the face at steady state is analyzed. It is found that: 1) when the surrounding rock is in a stable state, the deformation curve of the dome is smooth. When the surrounding rock of the face is unstable, the front of the face appears ahead. Deformation should be first strengthened on the surrounding rock in front of the face. 2) The arched foot is an important part of the instability of the surrounding rock. In order to prevent the expansion of the collapsed part, the arched part should be reinforced. 3) In order to obtain the limit state of surrounding rock stability, the strength of surrounding rock is reduced, and the strength reduction coefficient corresponding to the displacement sudden point is taken as the safety factor of rock stability around the hole, and the stability safety coefficients of surrounding rock of each construction step are greater than 1.2. 4) The dynamic standard values of deformation control in the whole construction stage are obtained by analyzing the deformation curves of each data monitoring point with time in the corresponding time period of each construction step.

scholarly journals INVESTIGATION OF THE GEOMECHANICAL STATE OF SOFT ADJOINING ROCKS UNDER PROTECTIVE CONSTRUCTIONS

2021 ◽  
Vol 36 (4) ◽  
pp. 61-71
Author(s):  
Serhii Nehrii ◽  
Tetiana Nehrii ◽  
Oksana Zolotarova ◽  
Serhii Volkov
Keyword(s):  
Physical And Mechanical Properties ◽  
New Approach ◽  
Soft Rocks ◽  
The Face ◽  
Geomechanical State ◽  
Rock Mass Failure ◽  
The Stability ◽  
Seam Mining ◽  
Mine Roadways

The conditions of coal seam mining in the mines of Ukraine have been considered. The problem of conducting coal mining by longwalls in the conditions of soft adjoining rocks, which concerns the protection of mine roadways located near the face, has been revealed. In such conditions, the existing protective constructions are ineffective due to the fact that they yield and get pressed into the soft rocks of the footwall. This indicated the need for research into the geomechanical state of soft rocks of the footwall. According to the results of known studies on the mechanism of rock mass failure around roadways and the data of physical and mechanical properties of the coal mass, which is represented by soft rocks, the correlation dependence has been obtained, the use of which allowed for the determination of the parameters of the rock deformation diagram and the establishment of the stability criterion of footwall rocks under the protection means and stability conditions of the geotechnical system “protective construction – adjoining rocks.” They are the basis of a new approach to ensure the stability of the roadways, which are supported behind the faces, by controlling the stress state in the system “protective construction – adjoining rocks.” This may be the basis for the development of new methods of protecting roadways in conditions of soft adjoining rocks.

How Can EU Law Respond to Populism?

2020 ◽  
Vol 40 (1) ◽  
pp. 183-213
Author(s):  
Mark Dawson
Keyword(s):  
Legal Order ◽  
Eu Law ◽  
Road Map ◽  
The Face ◽  
The Stability ◽  
Severe Anxiety ◽  
The Eu ◽  
Populist Movements

Abstract The rise in Europe of populist movements has created severe anxiety about the stability of the EU legal order. This article argues that, while populist ideas challenge numerous elements of the EU’s constitutional settlement, there exists no fundamental incompatibility between populism and EU law. By comparing its response to populism with attempts by EU law to stabilise its legal order in the face of political contestation arising from other political cleavages, the article discusses three different ways to understand the interaction between EU law and populism. EU law may seek to ‘survive’ the growth of populism by (i) bracketing or insulating its institutions from populist contestation, (ii) accommodating populist ideas or (iii) confronting the constitutional strategies populists utilise domestically. In examining the constitutional foundations of populism and its relation to emerging doctrines of EU law, the article seeks to build a road map of how populist movements might utilise or resist EU law in their development.

On the stability of crystal lattices. I

1940 ◽  
Vol 36 (2) ◽  
pp. 160-172 ◽  
Author(s):  
Max Born
Keyword(s):  
Positive Definiteness ◽  
Deformation Energy ◽  
The Body ◽  
Simple Explanation ◽  
Crystal Lattices ◽  
Simple Lattice ◽  
Macroscopic Deformation ◽  
The Face ◽  
The Stability ◽  
Central Forces

The stability of lattices is discussed from the standpoint of the method of small vibrations. It is shown that it is not necessary to determine the whole vibrational spectrum, but only its long wave part. The stability conditions are nothing but the positive definiteness of the macroscopic deformation energy, and can be expressed in the form of inequalities for the elastic constants. A new method is explained for calculating these as lattice sums, and this method is applied to the three monatomic lattice types assuming central forces. In this way one obtains a simple explanation of the fact that the face-centred lattice is stable, whereas the simple lattice is always unstable and the body-centred also except for small exponents of the attractive forces. It is indicated that this method might be used for an improvement of the, at present, rather unsatisfactory theory of strength.

On the stability of crystal lattices. II

1940 ◽  
Vol 36 (2) ◽  
pp. 173-182 ◽  
Author(s):  
Rama Dhar Misra
Keyword(s):  
Potential Energy ◽  
The Body ◽  
Complete Agreement ◽  
Stability Conditions ◽  
Crystal Lattices ◽  
Cubic Lattices ◽  
Simple Lattice ◽  
The Face ◽  
The Law ◽  
The Stability

On the assumption that the potential energy of the three cubic lattices of the Bravais type consists of two terms, an attractive one proportional to r−m and a repulsive one proportional to r−n, n > m, stability conditions are expressed in the form that two functions of the number n should be monotonically increasing. These functions have been calculated numerically for n = 4 to 15, and are represented as curves with the abscissa n. The result is that the face-centred lattice is completely stable, that the body-centred lattice is unstable for large exponents in the law of force, and that the simple lattice is always unstable,—in complete agreement with the results of Part I.

Journalism as Institution

2019 ◽  
Author(s):  
Tim P. Vos
Keyword(s):  
Institutional Theory ◽  
Historical Institutionalism ◽  
Journalism Studies ◽  
Shared Beliefs ◽  
Distinct Area ◽  
Social Authority ◽  
The Face ◽  
Cognitive Scripts ◽  
Path Dependent ◽  
The Stability

Journalism is an institution inasmuch as it is constituted by shared beliefs and norms, informal rules and routines, and explicit rules. These features of journalism are expressed in journalists’ practices and products but also in journalists’ own discourse about journalism, or in what institutional theorists refer to as institutional or cognitive scripts. Institutions are intellectually interesting objects of study because they both limit individuals’ agency and enable their ability to work productively and creatively. Thus they maintain stability but allow for adaptability. Institutions also denote a distinct area of social authority, signaling institutional autonomy. However, they are also inherently social and thus inextricably interconnected with other institutions. This autonomy and interconnection become the sources of ongoing battles over journalism’s legitimacy. Indeed, some institutions—including journalism—have not only lost some measure of legitimacy but the beliefs, norms, and rules that have constituted the institution have also been destabilized. Some even argue that journalism is deinstitutionalizing in the face of economic and technological changes. Others understand these changes as part of a broader process of institutional adaptation and reinstitutionalization. Early adaptations of so-called new institutionalism informed an early use of institutional theory in journalism studies. But institutional theory comes in a variety of forms—historical institutionalism and discursive institutions hold particular promise for journalism studies. Historical institutionalism directs attention to path-dependent processes that account for the stability of institutions over time. Meanwhile, discursive institutionalism highlights the importance of discourse as the social bond that maintains institutions but also provides the means for adaptation and change. Nevertheless, institutional theory remains underutilized in journalism studies and holds still untapped potential to explain intellectually interesting phenomena.

Partner-Specific Dependency and Guilt as Predictors of Forgiveness in Spanish University Women

2019 ◽  
Vol 22 ◽  
Author(s):  
Ana M. Beltrán-Morillas ◽  
Inmaculada Valor-Segura ◽  
Francisca Expósito
Keyword(s):  
Experimental Study ◽  
Romantic Relationships ◽  
Physical Violence ◽  
Sexual Infidelity ◽  
University Women ◽  
Interpersonal Transgressions ◽  
The Face ◽  
The Stability ◽  
The Relationship

AbstractInterpersonal transgressions often threaten the stability of the relationship. Within the scope of romantic relationships, physical violence and sexual infidelity have been considered the most difficult transgressions to forgive. Similarly, two variables considered relevant for forgiveness within the context of the couple are partner-specific dependency and the guilt experienced by the offended person. In that way, this research aims to approach the understanding of the forgiveness process of such transgressions. To this end, an experimental study was designed (N= 173 university women;Mage= 21.36,SD= 2.83), by which three indicators of forgiveness corresponding to the Transgression-Related Interpersonal Motivations Scale–18–Item Form (TRIM–18; “Revenge”, “Avoidance” and “Benevolence”), partner-specific dependency and sense of guilt of the offended person were examined in the face of the transgressions of physical violence and sexual infidelity. Results revealed that violence (vs. infidelity) is less forgiven (higher “Revenge”,p= .017, ηp2= .034). In addition, the results showed that high partner-specific dependency leads to further guilt which, in turn, leads to greater forgiveness towards the partner (less “Avoidance”,CIE= –.094,SE= .042, 95% CI [–.201, –.029]; and higher “Benevolence”,CIE= .080,SE= .037, 95% CI [.024, .173]) in light of violence (vs. infidelity). Last but not least, the previous findings and their possible implications for romantic relationships are discussed.

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