The expression of stlA in Photorhabdus luminescens is controlled by nutrient limitation

Photorhabdus is a genus of Gram-negative entomopathogenic bacteria that also maintain a mutualistic association with nematodes from the family Heterorhabditis. Photorhabdus has an extensive secondary metabolism that is required for the interaction between the bacteria and the nematode. A major component of this secondary metabolism is a stilbene molecule, called ST. The first step in ST biosynthesis is the non-oxidative deamination of phenylalanine resulting in the production of cinnamic acid. This reaction is catalyzed by phenylalanine-ammonium lyase, an enzyme encoded by the stlA gene. In this study we show, using a stlA-gfp transcriptional fusion, that the expression of stlA is regulated by nutrient limitation through a regulatory network that involves at least 3 regulators. We show that TyrR, a LysR-type transcriptional regulator that regulates gene expression in response to aromatic amino acids in E. coli, is absolutely required for stlA expression. We also show that stlA expression is modulated by σS and Lrp, regulators that are implicated in the regulation of the response to nutrient limitation in other bacteria. This work is the first that describes pathway-specific regulation of secondary metabolism in Photorhabdus and, therefore, our study provides an initial insight into the complex regulatory network that controls secondary metabolism, and therefore mutualism, in this model organism

Lean Cooperation: A Framework

While both concepts lean management and cooperation not only have received considerable attention in management literature but also have been combined e.g. in the field of supply chain literature, a comprehensive definition of lean cooperation is still missing. Whereas lean supply chain cooperation is only one aspect in a growing field, we aim at considering further forms of cooperation coming up and having consequences for the management of lean initiatives.Based on an extensive literature review, we develop a framework addressing lean cooperation and thus, allowing for systematization. Furthermore we find out that current literature mainly focusses on leancooperation along the supply chain. This paper presents other forms of cooperation focused on lean management. With a case study of lean cooperation within an industry cluster we will show the potential of knowledge-transfer on lean practices for individual firm´s  implementation.This paper provides a definition and a research framework for lean cooperation. Insights will be useful for further analysis of lean management roll-out within outlined forms of cooperation. Practitionerswill learn about benefits and restrictions of lean cooperation. The paper also is of value for researchers giving a structured outline of lean cooperation and stating fields for further research

Mapping the Political Twitterverse: Finding Connections Between Political Elites

Twitter provides a new and important tool for politicalactors, and is increasingly being used as such. In the2010 midterm elections, the vast majority of candidates forthe U.S. House of Representatives and virtually all candidatesfor U.S. Senate and governorships used Twitter toreach out to potential supporters, direct them to particularpieces of information, request campaign contributions, andmobilize their political action. Despite the level of activity,we have little understanding of what the political Twitterverselooks like in terms of communication and discourse.This project seeks to remedy that lack of understandingby mapping candidates for federal office in 2010 and theirfollowers, according to their use of the 4016 most used hashtags(keywords). Our data set is uniquely constructed fromtweets of most of the candidates running for the U.S. Houseof Representatives in 2010, all the candidates for the Senateand governorships, and a random sample of their followers.From this we utilize multidimensional scaling to constructa visual map based on hashtag usage. We find that ourdata have both local and global interpretations that reflectnot only political leaning but also strategies of communication.This study provides insight into innovation in newmedia usage in political behavior, as well as a snapshot ofthe political twitterverse in 2010

Warm Dark Matter versus Bumpy Power Spectra

In this paper we are exploring the differences between a Warm Dark Matter model and a CDM model where the power on a certain scale is reduced by introducing a narrow negative feature ("dip"). This dip is placed in a way so as to mimic the loss of power in the WDM model: both models have the same integrated power out to the scale where the power of the Dip model rises to the level of the unperturbed CDM spectrum again. Using N-body simulations we show that some of the large-scale clustering patterns of this new model follow more closely the usual CDM scenario while simultaneously suppressing small scale structures (within galactic halos) even more efficiently than WDM. The analysis in the paper shows that the new Dip model appears to be a viable alternative to WDM but it is based on different physics. Where WDM requires the introduction of a new particle species the Dip model is based on a non-standard inflationary period. If we are looking for an alternative to the currently challenged standard LCDM structure formation scenario, neither the LWDM nor the new Dip model can be ruled out based on the analysis presented in this paper. They both make very similar predictions and the degeneracy between them can only be broken with observations yet to come.Comment: 7 pages, 8 figures, replaced with MNRAS accepted version (minor revisions), high-resolution figures at http://astronomy.swin.edu.au/staff/aknebe

Study on adsorption capacity of corn stalks in decreasing the turbidity of Babura river water with batch operation

The adsorbent is a solid substance that can absorb certain components from the liquid phase. Most of the adsorbents are porous materials and the adsorption process takes place, especially in the porous wall or certain location inside that particle. The main objective of this research is to study the influence of the adsorbent’s surface area based on shape variation from corn stalk with adsorption ability to reduce the water river’s turbidity, the influence of time with adsorption capacity in reducing river water’s turbidity, the influence of adsorbent with water river and adsorption capacity, and defining adsorption kinetics from corn stalks. The shape of corn stalks that have been used such as spherical, half of spherical shape, and quarter of spherical shape. The volume of the sample is 250 mL. The measurement time is 300 minutes. The mass variations that have been used are 10 g, 15 g, and 20 g. The variation of sample takeover in the morning, afternoon, and evening. The measurement of adsorbent adsorption capacity in term of decreasing the turbidity of Babura River’s water is done by inputting the adsorbent into the sample, then the measurement of the water’s turbidity proceed by using a turbidity meter. The analysis result for the influence of the adsorbent’s surface area in decreasing Babura River’s water in the shape’s variation from spherical, half of spherical shape, and quarter of spherical shape is obtained in quarter of spherical shape. The highest amount of adsorbent in decreasing the turbidity of Babura River’s water is 20 g. Adsorption kinetics that has been used in the measurement of decreasing Babura River’s water turbidity is second order kinetic

Reversible Tuning of Collinear versus Chiral Magnetic Order by Chemical Stimulus

The Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction mediates collinear magnetic interactions via the conduction electrons of a non-magnetic spacer, resulting in a ferro- or antiferromagnetic magnetization in magnetic multilayers. The resulting spin-polarized charge transport effects have found numerous applications. Recently it has been discovered that heavy non-magnetic spacers are able to mediate an indirect magnetic coupling that is non-collinear and chiral. This Dzyaloshinskii-Moriya-enhanced RKKY (DME-RKKY) interaction causes the emergence of a variety of interesting magnetic structures, such as skyrmions and spin spirals. Applications using these magnetic quasi-particles require a thorough understanding and fine-tuning of the balance between the Dzyaloshinskii-Moriya interaction and other magnetic interactions, e.g., the exchange interaction and magnetic anisotropy contributions. Here, we show by spin-polarized scanning tunneling microscopy that the spin structure of manganese oxide chains on Ir(001) can reproducibly be switched from chiral to collinear antiferromagnetic interchain interactions by increasing the oxidation state of MnO$_2$ while the reverse process can be induced by thermal reduction. The underlying structural change is revealed by low-energy electron diffraction intensity data (LEED-IV) analysis. Density functional theory calculations suggest that the magnetic transition may be caused by a significant increase of the Heisenberg exchange upon oxidation.Comment: 6 pages, 3 figure

Restoring vascular nitric oxide formation by l-arginine improves the symptoms of intermittent claudication in patients with peripheral arterial occlusive disease

AbstractBackground. Administration of l-arginine improves nitric oxide (NO) formation and endothelium-dependent vasodilation in atherosclerotic patients.Objectives. We investigated in this double-blind, controlled study whether prolonged intermittent infusion therapy with l-arginine improves the clinical symptoms of patients with intermittent claudication, as compared with the endothelium-independent vasodilator prostaglandin E1, and control patients.Methods. Thirty-nine patients with intermittent claudication were randomly assigned to receive 2 × 8 g l-arginine/day, or 2 × 40 μg prostaglandin E1(PGE1)/day or no hemodynamically active treatment, for 3 weeks. The pain-free and absolute walking distances were assessed on a walking treadmill at 3 km/h, 12% slope, and NO-mediated, flow-induced vasodilation of the femoral artery was assessed by ultrasonography at baseline, at 1, 2 and 3 weeks of therapy and 6 weeks after the end of treatment. Urinary nitrate and cyclic guanosine-3′, 5′-monophosphate (GMP) were assessed as indices of endogenous NO production.Results. l-Arginine improved the pain-free walking distance by 230 ± 63% and the absolute walking distance by 155 ± 48% (each p < 0.05). Prostaglandin E1improved both parameters by 209 ± 63% and 144 ± 28%, respectively (each p < 0.05), whereas control patients experienced no significant change. l-Arginine therapy also improved endothelium-dependent vasodilation in the femoral artery, whereas PGE1had no such effect. There was a significant linear correlation between the l-arginine/asymmetric dimethylarginine (ADMA) ratio and the pain-free walking distance at baseline (r = 0.359, p < 0.03). l-Arginine treatment elevated the plasma l-arginine/ADMA ratio and increased urinary nitrate and cyclic GMP excretion rates, indicating normalized endogenous NO formation. Prostaglandin E1therapy had no significant effect on any of these parameters. Symptom scores assessed on a visual analog scale increased from 3.51 ± 0.18 to 8.3 ± 0.4 (l-arginine) and 7.0 ± 0.5 (PGE1; each p < 0.05), but did not significantly change in the control group (4.3 ± 0.4).Conclusions. Restoring NO formation and endothelium-dependent vasodilation by l-arginine improves the clinical symptoms of intermittent claudication in patients with peripheral arterial occlusive disease

Support Vector Machine Analysis of Functional Magnetic Resonance Imaging of Interoception Does Not Reliably Predict Individual Outcomes of Cognitive Behavioral Therapy in Panic Disorder with Agoraphobia

Background: The approach to apply multivariate pattern analyses based on neuro imaging data for outcome prediction holds out the prospect to improve therapeutic decisions in mental disorders. Patients suffering from panic disorder with agoraphobia (PD/AG) often exhibit an increased perception of bodily sensations. The purpose of this investigation was to assess whether multivariate classification applied to a functional magnetic resonance imaging (fMRI) interoception paradigm can predict individual responses to cognitive behavioral therapy (CBT) in PD/AG. Methods: This analysis is based on pretreatment fMRI data during an interoceptive challenge from a multicenter trial of the German PANIC-NET. Patients with DSM-IV PD/AG were dichotomized as responders (n = 30) or non-responders (n = 29) based on the primary outcome (Hamilton Anxiety Scale Reduction ≥50%) after 6 weeks of CBT (2 h/week). fMRI parametric maps were used as features for response classification with linear support vector machines (SVM) with or without automated feature selection. Predictive accuracies were assessed using cross validation and permutation testing. The influence of methodological parameters and the predictive ability for specific interoception-related symptom reduction were further evaluated. Results: SVM did not reach sufficient overall predictive accuracies (38.0–54.2%) for anxiety reduction in the primary outcome. In the exploratory analyses, better accuracies (66.7%) were achieved for predicting interoception-specific symptom relief as an alternative outcome domain. Subtle information regarding this alternative response criterion but not the primary outcome was revealed by post hoc univariate comparisons. Conclusion: In contrast to reports on other neurofunctional probes, SVM based on an interoception paradigm was not able to reliably predict individual response to CBT. Results speak against the clinical applicability of this technique