Inflorescence Architecture and Floral Morphology of Aratitiyopea lopezii (Xyridaceae)

Aratitiyopea lopezii is a robust perennial species of Xyridaceae from seasonally saturated, mid- to high-elevation, sandstone and granite sites in northern South America. The species lacks the scapose inflorescence characteristic of Xyridaceae and, having the gestalt of a rhizomatous bromeliad, it is seemingly aberrant in the family. However, closer examination confirms features consistent with the family and the previously noted morphological similarities to Orectanthe. Details of inflorescence structure and floral morphology are presented and compared to other genera of Xyridaceae

Circulating endothelial cell-derived extracellular vesicles mediate the acute phase response and sickness behaviour associated with CNS inflammation.

Brain injury elicits a systemic acute-phase response (APR), which is responsible for co-ordinating the peripheral immunological response to injury. To date, the mechanisms responsible for signalling the presence of injury or disease to selectively activate responses in distant organs were unclear. Circulating endogenous extracellular vesicles (EVs) are increased after brain injury and have the potential to carry targeted injury signals around the body. Here, we examined the potential of EVs, isolated from rats after focal inflammatory brain lesions using IL-1β, to activate a systemic APR in recipient naïve rats, as well as the behavioural consequences of EV transfer. Focal brain lesions increased EV release, and, following isolation and transfer, the EVs were sequestered by the liver where they initiated an APR. Transfer of blood-borne EVs from brain-injured animals was also enough to suppress exploratory behaviours in recipient naïve animals. EVs derived from brain endothelial cell cultures treated with IL-1β also activated an APR and altered behaviour in recipient animals. These experiments reveal that inflammation-induced circulating EVs derived from endothelial cells are able to initiate the APR to brain injury and are sufficient to generate the associated sickness behaviours, and are the first demonstration that EVs are capable of modifying behavioural responses

The Economic Archaeology of Roman Economic Performance

Recent years have witnessed a paradigm shift in the study of the Roman economy. Methodologically modern economic analysis is now far more acceptable than it once was, and archaeology has become the major source of empirical data for many questions. On the substantive side there is now a far clearer appreciation of the major changes that the Roman economy underwent, with substantial growth of population and aggregate production and even some improvements in standard of living, but followed by equally dramatic decline. This economic success was not limited to the imperial core, but also extended to the provinces

Theory of first-order layering transitions in thin helium films

Journals published by the American Physical Society can be found at http://journals.aps.org/Thin liquid He-4 films on graphite show evidence of layered growth with increasing number density via a succession of first-order phase transitions. These so-called ''layering transitions'' separate uniformly covering phases, such as monolayers and bilayers. The present work is a detailed theoretical study of such layering transitions using a Maxwell construction. We model the graphite surface by a strong substrate potential, and using a microscopic variational theory we obtain the uniform coverage solutions for liquid helium. For each layer, the theory yields the chemical potential mu and surface tension alpha as functions of coverage n, and from this we deduce mu(a). For each set of adjacent layers, we then obtain the crossing point in the curves of mu(alpha). In this way we obtain the values of mu, alpha, and surface coverages for the transition. Particular attention is paid to the monolayer-bilayer transition

Structure and Metal Binding Properties of Chlamydia trachomatis YtgA

Copyright © 2019 American Society for Microbiology. All Rights Reserved. The obligate intracellular pathogen Chlamydia trachomatis is a globally significant cause of sexually transmitted bacterial infections and the leading etiological agent of preventable blindness. The first-row transition metal iron (Fe) plays critical roles in chlamydial cell biology, and acquisition of this nutrient is essential for the survival and virulence of the pathogen. Nevertheless, how C. trachomatis acquires Fe from host cells is not well understood, since it lacks genes encoding known siderophore biosynthetic pathways, receptors for host Fe storage proteins, and the Fe acquisition machinery common to many bacteria. Recent studies have suggested that C. trachomatis directly acquires host Fe via the ATP-binding cassette permease YtgABCD. Here, we characterized YtgA, the periplasmic solute binding protein component of the transport pathway, which has been implicated in scavenging Fe(III) ions. The structure of Fe(III)-bound YtgA was determined at 2.0-Å resolution with the bound ion coordinated via a novel geometry (3 Ns, 2 Os [3N2O]). This unusual coordination suggested a highly plastic metal binding site in YtgA capable of interacting with other cations. Biochemical analyses showed that the metal binding site of YtgA was not restricted to interaction with only Fe(III) ions but could bind all transition metal ions examined. However, only Mn(II), Fe(II), and Ni(II) ions bound reversibly to YtgA, with Fe being the most abundant cellular transition metal in C. trachomatis. Collectively, these findings show that YtgA is the metal-recruiting component of the YtgABCD permease and is most likely involved in the acquisition of Fe(II) and Mn(II) from host cells. Importance: Chlamydia trachomatis is the most common bacterial sexually transmitted infection in developed countries, with an estimated global prevalence of 4.2% in the 15- to 49-year age group. Although infection is asymptomatic in more than 80% of infected women, about 10% of cases result in serious disease. Infection by C. trachomatis is dependent on the ability to acquire essential nutrients, such as the transition metal iron, from host cells. In this study, we show that iron is the most abundant transition metal in C. trachomatis and report the structural and biochemical properties of the iron-recruiting protein YtgA. Knowledge of the highresolution structure of YtgA will provide a platform for future structure-based antimicrobial design approaches

Resilience Analysis of Service Oriented Collaboration Process Management systems

Collaborative business process management allows for the automated coordination of processes involving human and computer actors. In modern economies it is increasingly needed for this coordination to be not only within organizations but also to cross organizational boundaries. The dependence on the performance of other organizations should however be limited, and the control over the own processes is required from a competitiveness perspective. The main objective of this work is to propose an evaluation model for measuring a resilience of a Service Oriented Architecture (SOA) collaborative process management system. In this paper, we have proposed resilience analysis perspectives of SOA collaborative process systems, i.e. overall system perspective, individual process model perspective, individual process instance perspective, service perspective, and resource perspective. A collaborative incident and maintenance notification process system is reviewed for illustrating our resilience analysis. This research contributes to extend SOA collaborative business process management systems with resilience support, not only looking at quantification and identification of resilience factors, but also considering ways of improving the resilience of SOA collaborative process systems through measures at design and run-time

Half-Earth or Whole Earth? Radical ideas for conservation, and their implications

AbstractWe question whether the increasingly popular, radical idea of turning half the Earth into a network of protected areas is either feasible or just. We argue that this Half-Earth plan would have widespread negative consequences for human populations and would not meet its conservation objectives. It offers no agenda for managing biodiversity within a human half of Earth. We call instead for alternative radical action that is both more effective and more equitable, focused directly on the main drivers of biodiversity loss by shifting the global economy from its current foundation in growth while simultaneously redressing inequality.</jats:p

Discriminative speaker recognition using Large Margin GMM

International audienceMost state-of-the-art speaker recognition systems are based on discriminative learning approaches. On the other hand, generative Gaussian mixture models (GMM) have been widely used in speaker recognition during the last decades. In an earlier work, we proposed an algorithm for discriminative training of GMM with diagonal covariances under a large margin criterion. In this paper, we propose an improvement of this algorithm which has the major advantage of being computationally highly efficient, thus well suited to handle large scale databases. We also develop a new strategy to detect and handle the outliers that occur in the training data. To evaluate the performances of our new algorithm, we carry out full NIST speaker identification and verification tasks using NIST-SRE'2006 data, in a Symmetrical Factor Analysis compensation scheme. The results show that our system significantly outperforms the traditional discriminative Support Vector Machines (SVM) based system of SVM-GMM supervectors, in the two speaker recognition tasks

An investigation of supervector regression for forensic voice comparison on small data

International audienceThe present paper deals with an observer design for a nonlinear lateral vehicle model. The nonlinear model is represented by an exact Takagi-Sugeno (TS) model via the sector nonlinearity transformation. A proportional multiple integral observer (PMIO) based on the TS model is designed to estimate simultaneously the state vector and the unknown input (road curvature). The convergence conditions of the estimation error are expressed under LMI formulation using the Lyapunov theory which guaranties bounded error. Simulations are carried out and experimental results are provided to illustrate the proposed observer

Protocol for the 'e-Nudge trial' : a randomised controlled trial of electronic feedback to reduce the cardiovascular risk of individuals in general practice [ISRCTN64828380]

Background: Cardiovascular disease (including coronary heart disease and stroke) is a major cause of death and disability in the United Kingdom, and is to a large extent preventable, by lifestyle modification and drug therapy. The recent standardisation of electronic codes for cardiovascular risk variables through the United Kingdom's new General Practice contract provides an opportunity for the application of risk algorithms to identify high risk individuals. This randomised controlled trial will test the benefits of an automated system of alert messages and practice searches to identify those at highest risk of cardiovascular disease in primary care databases. Design: Patients over 50 years old in practice databases will be randomised to the intervention group that will receive the alert messages and searches, and a control group who will continue to receive usual care. In addition to those at high estimated risk, potentially high risk patients will be identified who have insufficient data to allow a risk estimate to be made. Further groups identified will be those with possible undiagnosed diabetes, based either on elevated past recorded blood glucose measurements, or an absence of recent blood glucose measurement in those with established cardiovascular disease. Outcome measures: The intervention will be applied for two years, and outcome data will be collected for a further year. The primary outcome measure will be the annual rate of cardiovascular events in the intervention and control arms of the study. Secondary measures include the proportion of patients at high estimated cardiovascular risk, the proportion of patients with missing data for a risk estimate, and the proportion with undefined diabetes status at the end of the trial