Mechanosensitive Self-Replication Driven by Self-Organization

Self-replicating molecules are likely to have played an important role in the origin of life, and a small number of fully synthetic self-replicators have already been described. Yet it remains an open question which factors most effectively bias the replication toward the far-from-equilibrium distributions characterizing even simple organisms. We report here two self-replicating peptide-derived macrocycles that emerge from a small dynamic combinatorial library and compete for a common feedstock. Replication is driven by nanostructure formation, resulting from the assembly of the peptides into fibers held together by β sheets. Which of the two replicators becomes dominant is influenced by whether the sample is shaken or stirred. These results establish that mechanical forces can act as a selection pressure in the competition between replicators and can determine the outcome of a covalent synthesis.

Die Entstehung der frühkonstitutionellen Verfassungsurkunden Süddeutschlands : Motive - Einflüsse - Ergebnisse

Eine der Funktionen einer Verfassung sei, eine neue politische Ordnung zu etablieren. Doch welche Veranlassung gibt es hierzu, wer zeigt welches Interesse, welcher Zustand soll durch diese Neuordnung erreicht werden und insbesondere: wer hatte die Macht, diese neue Ordnung zu bestimmen? Nach Auflösung des Alten Reiches und Wegfall der Reichsverfassung hatten im Rahmen von Gesamtreformen die Länder teilweise auch begonnen, ihre inner-staatliche Verfassung neu zu bestimmen und diese aus unterschiedlichen Beweggründen und Zielsetzungen in einer Urkunde zu fassen. Durch Auflösung des Rheinbundes und der vertraglich gesicherten Souveränität ergab sich eine neue Situation, insbesondere durch die im Rahmen des Wiener Kongresses getroffene Vereinbarung des Artikels 13 der Bundesakte, in den Ländern landständische Verfassungen einzuführen. In der kurzen Periode zwischen dem Wiener Kongress mit der Deutschen Bundesakte 1815 und der Wiener Schlussakte 1820 entstanden u. a. die Verfassungen des Königreichs Bayern, des Großherzogtums Baden und des Königreichs Württemberg. Es soll in dieser Untersuchung ihre Entwicklung nachgezeichnet werden mit ihren Entstehungsbedingungen und Entstehungsursachen und hierbei aufgezeigt werden, welchen Einflüssen die Entwicklung unterworfen war, welche Ziele die Verfassungsgebung verfolgte und zu welchen Ergebnissen sie in den drei Ländern führte. Ausgehend von der Darstellung der Verfassungsarbeiten als Fortführung der in der Rheinbundzeit begonnenen Reformen und als dessen krönender Abschluss werden die Ausgangsbedingungen unter der Fragestellung beschrieben, ob es sich bei der Verfassungsarbeit um eine kontinuierliche Fortführung bereits früher bestehender Regelungen handelt. Die Entstehung der Verfassungen soll unter der Hauptüberlegung erfolgen, welche geistigen und empirischen Grundlagen zu dieser Form der Verfassung führten. Welche staatstheoretischen Überlegungen waren maßgeblich und wie wirkten diese auf die praktische Verfassungsgebung ein. In welcher Weise haben die Verfassungen Englands, Nordamerikas, Frankreichs und der anderen deutschen Staaten, in welchen es bereits zu Verfassungen gekommen ist, auf die Form der süddeutschen Verfassungen eingewirkt.One of the functions of a constitution is to establish a new political order. But what are the reason, who shows interest, what state are achieved by this reorganization and in particular: who had the power to define this new order? After the dissolution of the Roman Empire and abolition of the constitution had in the context of overall reforms, the countries also partially begun to determine their own national constitution and the newly recast in the different motivations and objectives in a document. By resolution of the Confederation and the contractually secured sovereignty resulted in a new situation, in particular by the introduction in Congress of Vienna agreement made in Article 13 of the Federal Act, in the estates of the countries' constitutions. In the short period between the Congress of Vienna with the German Federal Act of 1815 and the Vienna Final Act of 1820 created the constitutions of the Kingdom of Bavaria, the Grand Duchy of Baden and the Kingdom of Wurttemberg. It is to be traced in this study their development and their interference suppression-hung and the causes and conditions shown here, the influences on the development was subject to the objectives pursued the constitutional and what results they led in the three countries. Based on the representation of the Constitution works as a continuation of started in the Confederation of the Rhine-term reforms and as the culmination of the initial conditions are described under the issue of whether it is in the Constitution work for a steady continuation of already acting sooner to existing regulations. The emergence of constitutions is to take place under the main consideration, which intellectual and empirical basis for this form of the constitution led. What considerations were largely political theory and how this one worked on the practical constitution

The Power of Centralized PC Systems of Pushdown Automata

Parallel communicating systems of pushdown automata (PCPA) were introduced in (Csuhaj-Varj{\'u} et. al. 2000) and in their centralized variants shown to be able to simulate nondeterministic one-way multi-head pushdown automata. A claimed converse simulation for returning mode (Balan 2009) turned out to be incomplete (Otto 2012) and a language was suggested for separating these PCPA of degree two (number of pushdown automata) from nondeterministic one-way two-head pushdown automata. We show that the suggested language can be accepted by the latter computational model. We present a different example over a single letter alphabet indeed ruling out the possibility of a simulation between the models. The open question about the power of centralized PCPA working in returning mode is then settled by showing them to be universal. Since the construction is possible using systems of degree two, this also improves the previous bound three for generating all recursively enumerable languages. Finally PCPAs are restricted in such a way that a simulation by multi-head automata is possible

Passing to the Limit in a Wasserstein Gradient Flow: From Diffusion to Reaction

We study a singular-limit problem arising in the modelling of chemical reactions. At finite {\epsilon} > 0, the system is described by a Fokker-Planck convection-diffusion equation with a double-well convection potential. This potential is scaled by 1/{\epsilon}, and in the limit {\epsilon} -> 0, the solution concentrates onto the two wells, resulting into a limiting system that is a pair of ordinary differential equations for the density at the two wells. This convergence has been proved in Peletier, Savar\'e, and Veneroni, SIAM Journal on Mathematical Analysis, 42(4):1805-1825, 2010, using the linear structure of the equation. In this paper we re-prove the result by using solely the Wasserstein gradient-flow structure of the system. In particular we make no use of the linearity, nor of the fact that it is a second-order system. The first key step in this approach is a reformulation of the equation as the minimization of an action functional that captures the property of being a curve of maximal slope in an integrated form. The second important step is a rescaling of space. Using only the Wasserstein gradient-flow structure, we prove that the sequence of rescaled solutions is pre-compact in an appropriate topology. We then prove a Gamma-convergence result for the functional in this topology, and we identify the limiting functional and the differential equation that it represents. A consequence of these results is that solutions of the {\epsilon}-problem converge to a solution of the limiting problem.Comment: Added two sections, corrected minor typos, updated reference

Genotype-phenotype correlation in adult-onset acid maltase deficiency

We performed a clinical, biochemical, and genetic study in 16 patients from 11 families with adult‐onset acid maltase deficiency. All patients were compound heterozygotes and carried the IVS1(– 13T→G) transversion on one allele; the second allele harbored either a deletion of a T at position 525 in exon 2 (7 probands, 64%) or a deletion of exon 18 (1 proband, 9%). Detrioration of handicap was related to age, and decrease in vital capacity to duration of the symptomatic stage. Respiratory insufficiency was never the first manifestation. The levels of activity of serum creatine kinase and of β‐glucosidase in peripheral blood cells or muscle were helpful for the diagnosis, but did not have prognostic value. The adult form of acid maltase deficiency appears to be both clinically and genetically rather homogeneous; decrease of β‐glucosidase activity is the final common pathway leading to destruction of muscle fibers and progression of muscle weakness over a period of years. Copyrigh

Testing Logselfsimilarity of Soil Particle Size Distribution: Simulation with Minimum Inputs

Particle size distribution (PSD) greatly influences other soil physical properties. A detailed textural analysis is time-consuming and expensive. Soil texture is commonly reported in terms of mass percentages of a small number of size fractions (typically, clay, silt and sand). A method to simulate the PSD from such a poor description or even from the poorest description, consisting in the mass percentages of only two soil size fractions, would be extremly useful for prediction purposes. The goal of this paper is to simulate soil PSDs from the minimum number of inputs, i.e., two and three textural fraction contents, by using a logselfsimilar model and an iterated function system constructed with these data. High quality data on 171 soils are used. Additionally, the characterization of soil texture by entropy-based parameters provided by the model is tested. Results indicate that the logselfsimilar model may be a useful tool to simulate PSD for the construction of pedotransfer functions related to other soil properties when textural information is limited to moderate textural data

Glycogenosis type II (acid maltase deficiency)

Glycogen storage disease type II (GSD II/glycogenosis type II/Pompe's disease/acid maltase deficiency) is caused by the deficiency of lysosomal α-glucosidase resulting in lysosomal accumulation of glycogen. The disease is inherited as an autosomal recessive trait and is clinically heterogeneous. Early and late onset phenotypes are distinguished. Insight in the molecular nature of the lysosomal α-glucosidase deficiency and the underlying genetic defect has increased significantly during the past decade. This minireview on GSD II was written at the occasion of The International Symposium on Glycolytic and Mitochondrial Defects in Muscle and Nerve, held in Osaka, Japan, July 1994. It is an update of current literature, but also includes original data from the collaborating authors on mutations occurring in the lysosomal α-glucosidase gene and on prenatal diagnosis by chorionic villus sampling. The genotype–phenotype correlation and the prospects for therapy are addressed

Special fast diffusion with slow asymptotics. Entropy method and flow on a Riemannian manifold

We consider the asymptotic behaviour of positive solutions $u(t,x)$ of the fast diffusion equation $u_t=\Delta (u^{m}/m)={\rm div} (u^{m-1}\nabla u)$ posed for x\in\RR^d, $t>0$, with a precise value for the exponent $m=(d-4)/(d-2)$. The space dimension is $d\ge 3$ so that $m<1$, and even $m=-1$ for $d=3$. This case had been left open in the general study \cite{BBDGV} since it requires quite different functional analytic methods, due in particular to the absence of a spectral gap for the operator generating the linearized evolution. The linearization of this flow is interpreted here as the heat flow of the Laplace-Beltrami operator of a suitable Riemannian Manifold (\RR^d,{\bf g}), with a metric ${\bf g}$ which is conformal to the standard \RR^d metric. Studying the pointwise heat kernel behaviour allows to prove {suitable Gagliardo-Nirenberg} inequalities associated to the generator. Such inequalities in turn allow to study the nonlinear evolution as well, and to determine its asymptotics, which is identical to the one satisfied by the linearization. In terms of the rescaled representation, which is a nonlinear Fokker--Planck equation, the convergence rate turns out to be polynomial in time. This result is in contrast with the known exponential decay of such representation for all other values of $m$.Comment: 37 page

β-Mannosidase deficiency: Heterogeneous manifestation in the first female patient and her brother

Summary β-Mannosidase deficiency was demonstrated in fibroblasts of a girl who showed severe psychomotor retardation, bone deformities and gargoylism and recurrent skin and r

Aspectos técnico-ambientais da produção orgânica na região citrícola do Vale do Rio Caí, RS.

Há uma preocupação crescente sobre a necessidade de produção e consumo de alimentos mais saudáveis, sem uso de agrotóxicos nem fertilizantes sintético-industriais. Neste contexto se insere a prática da agricultura orgânica, que, contudo, apresenta resultados ainda pouco avaliados nos meios acadêmicos e científicos. Assim, pretendeu-se nesta pesquisa diagnosticar aspectos técnico-ambientais da produção orgânica na região citrícola do Vale do Rio Caí, no Rio Grande do Sul. Inicialmente, foram selecionadas propriedades de oito agricultores familiares, todas já convertidas ao sistema orgânico de produção, sendo aplicadas entrevistas semi-estruturadas. Os produtores mostram-se satisfeitos com o sistema orgânico de produção e revelam bom conhecimento sobre o ambiente, plantas, solos e processos agroecológicos, adquiridos através da participação em eventos técnicos e em reuniões da Cooperativa Ecocitrus. A constante troca de experiências entre esses agricultores tem melhorado sua qualificação técnica, além de melhor conscientizá-los nos aspectos políticos, econômicos e sociais