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We consider the scenario emerging from the dynamics of a generalized Born-Infeld theory. The equation of state describing this system is given in terms of the energy density $\ensuremath{\rho}$ and pressure p by the relationship $p=\ensuremath{-}A/{\ensuremath{\rho}}^{\ensuremath{\alpha}},$ where A is a positive constant and $0<\ensuremath{\alpha}<~1.$ We discuss the conditions under which homogeneity arises and show that this equation of state describes the evolution of a universe evolving from a phase dominated by nonrelativistic matter to a phase dominated by a cosmological constant via an intermediate period where the effective equation of state is given by $p=\ensuremath{\alpha}\ensuremath{\rho}.$

Abstract Aims Vegetation classification consistent with the Braun‐Blanquet approach is widely used in Europe for applied vegetation science, conservation planning and land management. During the long history of syntaxonomy, many concepts and names of vegetation units have been proposed, but there has been no single classification system integrating these units. Here we (1) present a comprehensive, hierarchical, syntaxonomic system of alliances, orders and classes of Braun‐Blanquet syntaxonomy for vascular plant, bryophyte and lichen, and algal communities of Europe; (2) briefly characterize in ecological and geographic terms accepted syntaxonomic concepts; (3) link available synonyms to these accepted concepts; and (4) provide a list of diagnostic species for all classes. Location European mainland, Greenland, Arctic archipelagos (including Iceland, Svalbard, Novaya Zemlya), Canary Islands, Madeira, Azores, Caucasus, Cyprus. Methods We evaluated approximately 10 000 bibliographic sources to create a comprehensive list of previously proposed syntaxonomic units. These units were evaluated by experts for their floristic and ecological distinctness, clarity of geographic distribution and compliance with the nomenclature code. Accepted units were compiled into three systems of classes, orders and alliances (EuroVegChecklist, EVC ) for communities dominated by vascular plants ( EVC 1), bryophytes and lichens ( EVC 2) and algae ( EVC 3). Results EVC 1 includes 109 classes, 300 orders and 1108 alliances; EVC 2 includes 27 classes, 53 orders and 137 alliances, and EVC 3 includes 13 classes, 24 orders and 53 alliances. In total 13 448 taxa were assigned as indicator species to classes of EVC 1, 2087 to classes of EVC 2 and 368 to classes of EVC 3. Accepted syntaxonomic concepts are summarized in a series of appendices, and detailed information on each is accessible through the software tool EuroVegBrowser. Conclusions This paper features the first comprehensive and critical account of European syntaxa and synthesizes more than 100 yr of classification effort by European phytosociologists. It aims to document and stabilize the concepts and nomenclature of syntaxa for practical uses, such as calibration of habitat classification used by the European Union, standardization of terminology for environmental assessment, management and conservation of nature areas, landscape planning and education. The presented classification systems provide a baseline for future development and revision of European syntaxonomy.

Greening roofs or walls to cool down city areas during summer, to capture storm water, to abate pollution, and to increase human well-being while enhancing biodiversity: nature-based solutions (NBS) refer to the sustainable management and use of nature for tackling societal challenges. Building on and comple- menting traditional biodiversity conservation and management strategies, NBS integrate science, policy, and practice and create biodiversity benefits in terms of diverse, well-managed ecosystems.

The objective of this research is to understand the link and evolution between the concepts of knowledge management, organizational learning and memory. Seeking a better clarification of concepts, discussing them in the theoretical field, understanding their evolution in the last decades. A systematic literature review was developed by synthesizing concepts. From two databases, a total of 2511 scientific articles between 1960 and 2017 were analyzed, divided into two studies. Organizational learning is seen as a dynamic process based on knowledge and is translated through various levels of activity. The ability of an organization to use and leverage the knowledge is heavily dependent on its Human Resources, which are effectively who creates, shares and uses that knowledge. Knowledge management is seen as the management of the processes of creation, storage, access, and dissemination of the intellectual resources of an organization. Organizations must consider your main objective as increasing the capacity of individuals and organizational knowledge enhancers. Managers should pay special attention to the more general knowledge associated with the context of the firm, as it supports the introduction of various types of innovation. Knowledge can be encouraged by a set of collaborative practices of HRM. We can consider organizational learning as a process and organizational memory as the corresponding output. Thus, establishing the relationship that the organizational memory is a consequence of organizational learning. Key concepts that can be used in the new future research are summarized, highlighting its application and diagnosis for organizations, fomenting the strategic decision-making.

The very recently observed D(*)(sJ)(2317)(+) meson is described as a quasibound scalar csmacr; state in a unitarized meson model, owing its existence to the strong 3P0 Okubo-Zweig-Iizuka-allowed coupling to the nearby S-wave DK threshold. By the same mechanism, a scalar D(*)(0)(2100-2300) resonance is predicted above the Dpi threshold. These scalars are the charmed cousins of the light scalar nonet f(0)(600), f(0)(980), K(*)(0)(800), and a(0)(980), reproduced by the same model. The standard cnmacr; and csmacr; charmed scalars D0 and D(s0), cousins of the scalar nonet f(0)(1370), f(0)(1500), K(*)(0)(1430), and a(0)(1450), are predicted to lie at about 2.64 and 2.79 GeV, respectively, both with a width of some 200 MeV.

From group hunting to global warming, how to deal with collective action may be formulated in terms of a public goods game of cooperation. In most cases, contributions depend on the risk of future losses. Here, we introduce an evolutionary dynamics approach to a broad class of cooperation problems in which attempting to minimize future losses turns the risk of failure into a central issue in individual decisions. We find that decisions within small groups under high risk and stringent requirements to success significantly raise the chances of coordinating actions and escaping the tragedy of the commons. We also offer insights on the scale at which public goods problems of cooperation are best solved. Instead of large-scale endeavors involving most of the population, which as we argue, may be counterproductive to achieve cooperation, the joint combination of local agreements within groups that are small compared with the population at risk is prone to significantly raise the probability of success. In addition, our model predicts that, if one takes into consideration that groups of different sizes are interwoven in complex networks of contacts, the chances for global coordination in an overall cooperating state are further enhanced.

We study the dependence of the location of the cosmic microwave background radiation peaks on the parameters of the generalized Chaplygin gas model, whose equation of state is given by $p=\ensuremath{-}A/{\ensuremath{\rho}}^{\ensuremath{\alpha}},$ where A is a positive constant and $0<\ensuremath{\alpha}<~1.$ We find, in particular, that observational data arising from Archeops, BOOMERANG, supernova and high-redshift observations allow constraining significantly the parameter space of the model. Our analysis indicates that the emerging model is clearly distinguishable from the $\ensuremath{\alpha}=1$ Chaplygin case and the $\ensuremath{\Lambda}\mathrm{CDM}$ model.

OBJECTIVE: To compare short-term surgical outcomes and quality of life (QOL) between single-port laparoscopic cholecystectomy (SPLC) and classic 4-port laparoscopic cholecystectomy (CLC). BACKGROUND: There is significant interest in further reducing the trauma associated with surgical procedures. Although a number of observational studies have suggested that SPLC is a feasible alternative to CLC, there is a lack of data from randomized studies validating any benefit over CLC. METHODS: Eligible patients were randomized to receive SPLC or CLC. Operative and perioperative outcomes, including cosmesis and QOL were analyzed. RESULTS: Forty-three patients were randomized to SPLC (n = 21) or CLC (n = 22). There were no significant differences between groups for most preoperative demographics, American Society of Anesthesiology score, gallstone characteristics, local inflammation, blood loss, or length of stay. Patients undergoing SPLC were older than those receiving CLC (57.3 years vs. 45.8 years, P < 0.05). Operative times for SPLC were greater than CLC (88.5 minutes vs. 44.8 minutes, P < 0.05). Overall and cosmetic satisfaction, QOL as determined by the SF-36 survey, postoperative complications, and post-operative pain scores between discharge and 2-week postoperative visit were not significantly different between groups. Wound infection rates were similar in both groups. The SPLC group contained 1 retained bile duct stone, 1-port site hernia, and 1 postoperative port site hemorrhage. CONCLUSIONS: SPLC procedure time was longer and incurred more complications than CLC without significant benefits in patient satisfaction, postoperative pain and QOL. SPLC may be offered in carefully selected patients. Larger randomized trials performed later in the learning curve with SPLC may identify more subtle advantages of one method over another.

We discuss the dynamics of adaptive evolution in asexual (clonal) populations. The classical 'periodic selection' model of clonal evolution assumed that beneficial mutations are very rare and therefore substitute unfettered into populations as occasional, isolated events. Newer models allow for the possibility that beneficial mutations are sufficiently common to coexist and compete for fixation within populations. Experimental evolution studies in microbes provide empirical support for stochastic models in which both selection and mutation are strong effects and clones compete for fixation; however, the relative importance of competition among clones bearing mutations of different selective effects versus competition among clones bearing multiple mutations remains unresolved. We provide some new theoretical results, moreover, suggesting that population dynamics consistent with the periodic selection model can arise even in a deterministic model that can accommodate a very high beneficial mutation rate.

Obesity is an endemic health problem in most developed countries, requiring serious public health attention. The first Portuguese nationwide representative survey about obesity (with objective anthropometric measurement) was undertaken from 1995 to 1998. This paper presents data coming from the second and most recent nationwide representative study of obesity, with objective measurement of weight, height, waist and hip circumferences. Data were collected between January 2003 and January 2005. The survey collected objective body mass index (BMI) values of 8116 participants aged 18-64. Main findings were: 2.4% of the sample had low weight (BMI < 18.5), 39.4% were overweight (BMI between 25.0 and 29.9), and 14.2% obese (BMI > or = 30). Waist circumference measurement showed that 45.6% of the sample suffers increased cardiovascular health risks associated with high waist circumference. The overall overweight/obesity prevalence increased from 49.6% (in 1995-1998) to 53.6% (in 2003-2005). These data suggest that although obesity was identified as a public health problem one decade ago, action to reduce it does not seem to have been very effective to date. Well-defined public health intervention must be targeted to specific population groups where higher levels of obesity prevalence were found: low socioeconomic level groups and low-education level groups.

The overall purpose of this article is to review theory and research on interpretive journalism, one of the key concepts in research on the style and character of news journalism. While it is often claimed that news journalism over recent decades has changed from being predominantly descriptive to becoming increasingly interpretive, our review suggests that there is a lack of systematic research in this area. The literature is furthermore characterized by different conceptualizations and operationalizations of interpretive journalism, as well as by different normative assumptions. Taken together, this suggests not only insufficient conceptual clarity, but also problems related to the comparability and cumulativity of findings. To remedy this, and based on our review of how interpretive journalism has been conceptualized and operationalized, this article suggests how interpretive journalism should be conceptualized and operationalized in order to increase conceptual clarity, comparability across studies, and ultimately research cumulativity.

Significance One of the greatest challenges in addressing global environmental problems such as climate change, which involves public goods and common-pool resources, is achieving cooperation among peoples. There are great disparities in wealth among nations, and this heterogeneity can make agreements much more difficult to achieve (e.g., regarding implementation of climate change mitigation). This paper incorporates wealth inequality into a public goods dilemma, including an asymmetric distribution of wealth representative of existing inequalities among nations. Without homophily (imitation of like agents), inequality actually makes cooperation easier to achieve; homophily, however, can undercut this, leading to collapse because poor agents may contribute less. Understanding such effects may enhance the ability to achieve agreements on climate change and other issues.

Abstract Strengthening and rehabilitation by reinforced concrete jacketing of columns is assessed, considering different practical aspects: anchoring and slab crossing of the added longitudinal reinforcement, interface surface preparation, spacing of added stirrups, temporary shoring of the structure and addition of new concrete. Recent research on these topics and the main recommendations to achieve good RC jacketing are presented. Copyright © 2003 John Wiley &amp; Sons, Ltd.

Sugars that contain glucose, such as sucrose, are generally preferred to artificial sweeteners owing to their post-ingestive rewarding effect, which elevates striatal dopamine (DA) release. While the post-ingestive rewarding effect, which artificial sweeteners do not have, signals the nutrient value of sugar and influences food preference, the neural circuitry that mediates the rewarding effect of glucose is unknown. In this study, we show that optogenetic activation of melanin-concentrating hormone (MCH) neurons during intake of the artificial sweetener sucralose increases striatal dopamine levels and inverts the normal preference for sucrose vs sucralose. Conversely, animals with ablation of MCH neurons no longer prefer sucrose to sucralose and show reduced striatal DA release upon sucrose ingestion. We further show that MCH neurons project to reward areas and are required for the post-ingestive rewarding effect of sucrose in sweet-blind Trpm5(-/-) mice. These studies identify an essential component of the neural pathways linking nutrient sensing and food reward. DOI: http://dx.doi.org/10.7554/eLife.01462.001.

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Developing B cells must pass a series of checkpoints that are regulated by membrane-bound Ig(mu) through the Igalpha-Igbeta signal transducers. To determine how Ig(mu) expression affects B cell development and Ab selection in humans we analyzed Ig gene rearrangements in pro-B cells from two patients who are unable to produce Ig(mu) proteins. We find that Ig(mu) expression does not affect V(H), D, or J(H) segment usage and is not required for human Igkappa and Iglambda recombination or expression. However, the heavy and light chains found in pro-B cells differed from those in peripheral B cells in that they showed unusually long CDR3s. In addition, the Igkappa repertoire in Ig(mu)-deficient pro-B cells was skewed to downstream Jkappas and upstream Vkappas, consistent with persistent secondary V(D)J rearrangements. Thus, Ig(mu) expression is not required for secondary V(D)J recombination in pro-B cells. However, B cell receptor expression shapes the Ab repertoire in humans and is essential for selection against Ab's with long CDR3s.

OBJECTIVE: To assess the effect of exercise training by using the Nintendo Wii Fit video game and balance board system on balance and gait in adults with Parkinson disease (PD). DESIGN: A prospective interventional cohort study. SETTING: An outpatient group exercise class. PARTICIPANTS: Ten subjects with PD, Hoehn and Yahr stages 2.5 or 3, with a mean age of 67.1 years; 4 men, 6 women. INTERVENTIONS: The subjects participated in supervised group exercise sessions 3 times per week for 8 weeks by practicing 3 different Wii balance board games (marble tracking, skiing, and bubble rafting) adjusted for their individualized function level. The subjects trained for 10 minutes per game, a total of 30 minutes training per session. MAIN OUTCOME MEASUREMENTS: Pre-and postexercise training, a physical therapist evaluated subjects' function by using the Berg Balance Scale, Dynamic Gait Index, and Sharpened Romberg with eyes open and closed. Postural sway was assessed at rest and with tracking tasks by using the Wii balance board. The subjects rated their confidence in balance by using the Activities-specific Balance Confidence scale and depression on the Geriatric Depression Scale. RESULTS: Balance as measured by the Berg Balance Scale improved significantly, with an increase of 3.3 points (P = .016). The Dynamic Gait Index improved as well (mean increase, 2.8; P = .004), as did postural sway measured with the balance board (decreased variance in stance with eyes open by 31%; P = .049). Although the Sharpened Romberg with eyes closed increased by 6.85 points and with eyes opened by 3.3 points, improvements neared significance only for eyes closed (P = .07 versus P = .188). There were no significant changes on patient ratings for the Activities-specific Balance Confidence (mean decrease, -1%; P = .922) or the Geriatric Depression Scale (mean increase, 2.2; P = .188). CONCLUSIONS: An 8-week exercise training class by using the Wii Fit balance board improved selective measures of balance and gait in adults with PD. However, no significant changes were seen in mood or confidence regarding balance.

We present a determination of the gluon polarization Delta G/G in the nucleon, based on the helicity asymmetry of quasi-real photoproduction events, Q^2<1(GeV/c)^2, with a pair of large transverse-momentum hadrons in the final state. The data were obtained by the COMPASS experiment at CERN using a 160 GeV polarized muon beam scattered on a polarized 6-LiD target. The helicity asymmetry for the selected events is <A_||/D> = 0.002 +- 0.019(stat.) +- 0.003(syst.). From this value, we obtain in a leading-order QCD analysis Delta G/G=0.024 +- 0.089(stat.) +- 0.057(syst.) at x_g = 0.095 and mu^2 =~ 3 (GeV}/c)^2.

The absolute decay width of a single-particle level in a deformed potential is evaluated exactly. Experimental data are analyzed by using the formalism developed here. It is found that proton decay is a powerful tool to determine the deformation of nuclei as well as to probe small components of the wave functions of the decaying states. This will allow one to study the behavior of single-particle resonances in nuclei close to the drip line, and may guide future experiments.

Foreign direct investment (FDI) influences host country's economic growth through several channels. Empirically, a variety of studies considers that FDI generate economic growth but others conclude that FDI is a source of negative effects. By reviewing existing theoretical and empirical literature, we intend to shed light on the main explanations for the mixed results. The main conclusion is that the effects of FDI on economic growth depend on the domestic conditions of the host country (e.g., human capital, economic and technological conditions, degree of openness of its economy). Thus, the host countries governments have a key role in creating the conditions that allow for the leverage of the positive effects or for the reduction of the negative effects of FDI on the host country's economic growth.