What country, university or research institute, performed the best on COVID-19? Bibliometric analysis of scientific literature

In this article, we conduct data mining to discover the countries, universities and companies, produced or collaborated the most research on Covid-19 since the pandemic started. We present some interesting findings, but despite analysing all available records on COVID-19 from the Web of Science Core Collection, we failed to reach any significant conclusions on how the world responded to the COVID-19 pandemic. Therefore, we increased our analysis to include all available data records on pandemics and epidemics from 1900 to 2020. We discover some interesting results on countries, universities and companies, that produced collaborated most the most in research on pandemic and epidemics. Then we compared the results with the analysing on COVID-19 data records. This has created some interesting findings that are explained and graphically visualised in the article

Characterization of modular bacteriophage endolysins from giant phiKZ related myoviridae phages OBP, 201phi2-1 and PVP-SEl

Peptidoglycan lytic enzymes (endolysins) of bacteriophages have a major role in bacterial lysis at the end of the phage replication cycle. These endolysins turned out to be potential antibacterial compounds to combat a broad range of Gram-positive pathogens, yet Gram-negative bacteria remain unharmed due to their impermeable outer membrane. With this background, we recently characterized three new endolysins from Gramnegative origin: OBPgp279 (Pseudomonas fluorescens phage OBP), PVP-SElgpl46 (Salmonella Enteritidis phage PVP-SEl) and 20lphi2-lgp229 (Pseudomonas chlororaphis phage 201phi2-1). These endolysins share a modular structure with anNterminal cell wall binding domain and a C-terrninal catalytic domain, a unique property of endolysins belonging to giant phiKZ related phages and some other giant, non-related myoviruses. All three endolysins showed strong muralytic activity on the peptidoglycan of a broad range of Gram-negative bacteria, a feature linked with their modular composition. In case of OBPgp279, the presence of the cell wall binding domain is responsible for 38 % of the total muralytic activity. Moreover, the binding domain of PVP-SE1gp146 has a binding affinity for Salmonella peptidoglycan that falls within the range of typical cell adhesion molecules. Remarkably, PVP-SElgp146 shows thermoresistant properties up to temperatures of 90°C, making it a potential candidate as antibacterial in hurdle technology for food preservation. OBPgp279, on the other hand. is able to pass the outer membrane of P. aeruginosa PAO 1 using an unknown mechanism, thereby gaining access to its peptidoglycan and reduce the bacterium with !logarithmic unit. Addition of the outer membrane permeabilizer EDTA significantly increased the antibacterial activity of the three endolysins up to 2-3 logarithmic units. This research offers perspectives towards elucidation of the structural differences explaining the unique biochemical and antibacterial properties ofOBPgp279, PVP-SE1gp146 and 201phi2- lgp229. Furthermore, these endolysins extensively enlarge the pool of potential antibacterial compounds used for treatment of Gram-negative bacterial infections

Exploiting the proteins encoded in the genome of the broad host range Salmonella phage PVP-SE1

Foodborne diseases are of major concern due to its worldwide impact. Salmonella has been constantly pointed as the second leading cause constituting thus a major public health burden with significant impact in the society costs. The increased resistance of bacteria toward antimicrobials and the recent legislation restricting the use of antibiotics as growth promoters in animal production requires alternatives to the use of antibiotics in the control of this zoonotic pathogen. Consequently, there is an urgent need to control this bacterial genus. To accomplish this, fast and accurate techniques for early detection are also required. Bacteriophages (phages) as natural predators of bacteria offer a great potential for pathogens detection and control due to their high specificity and killing ability. We have isolated and characterize a broad host range phage with great potential for Salmonella control. This phage encodes several proteins with great biotechnological potential which include the phage tail fibers with application in Salmonella detection, peptidoglycan hydrolases and holins that produce lysis of the bacterial cells and depolymerases which can decrease the ability of the cells to form biofilms and consequently decrease resistance of the cells to treatment. In this work we will identify these proteins and envisage their biotechnological

Defining adaptive learning design templates for combining design and runtime adaptation in aLFanet

Adaptive features are expected to improve the effectiveness of the learning process in online learning. Nevertheless, most current adaptive sys-tems do not deal with combining design and runtime adaptations. To take ad-vantage of this combination a new adaptive iLMS based on standards, called aLFanet, is being developed. The system includes: (i) an authoring tool to de-velop courses IMS-LD compliant, (ii) an adaptive engine based on a multi-agent architecture which is intended to cope with several adaptive tasks for various types of users (learners, authors and tutors), (iii) a set of advanced pedagogical scenarios that combine design and runtime adaptations to make the authoring of these type of adaptive courses feasible. In this paper we focus on the types of adaptations and the process we have defined to facilitate the con-struction of the adaptive scenarios.EC 5th Framework IST-2001-3328

Mid-IR Luminosities and UV/Optical Star Formation Rates at z<1.4

UV continuum and mid-IR emission constitute two widely used star formation indicators at intermediate and high redshifts. We study 2430 galaxies with z<1.4 in the Extended Groth Strip with MIPS 24 mic observations from FIDEL, spectroscopy from DEEP2, and UV, optical, and near-IR photometry from AEGIS. The data are coupled with stellar population models and Bayesian SED fitting to estimate dust-corrected SFRs. In order to probe the dust heating from stellar populations of various ages, the derived SFRs were averaged over various timescales--from 100 Myr for "current" SFR to 1--3 Gyr for long-timescale SFRs. These SED-based UV/optical SFRs are compared to total infrared luminosities extrapolated from 24 mic observations. We find that for the blue, actively star forming galaxies the correlation between the IR luminosity and the UV/optical SFR shows a decrease in scatter when going from shorter to longer SFR-averaging timescales. We interpret this as the greater role of intermediate age stellar populations in heating the dust than what is typically assumed. This holds over the entire redshift range. Many so-called green valley galaxies are simply dust-obscured actively star-forming galaxies. However, there exist 24 mic-detected galaxies, some with L>10^11 L_sun, yet with little current star formation. For them a reasonable amount of dust absorption of stellar light is sufficient to produce the observed levels of IR. In our sample optical and X-ray AGNs do not contribute on average more than ~50% to the mid-IR luminosity, and we see no evidence for a large population of "IR excess" galaxies (Abridged).Comment: Accepted for publication in ApJ. Content identical to arXiv version 1. No color figure

Evolutionary connectionism: algorithmic principles underlying the evolution of biological organisation in evo-devo, evo-eco and evolutionary transitions

The mechanisms of variation, selection and inheritance, on which evolution by natural selection depends, are not fixed over evolutionary time. Current evolutionary biology is increasingly focussed on understanding how the evolution of developmental organisations modifies the distribution of phenotypic variation, the evolution of ecological relationships modifies the selective environment, and the evolution of reproductive relationships modifies the heritability of the evolutionary unit. The major transitions in evolution, in particular, involve radical changes in developmental, ecological and reproductive organisations that instantiate variation, selection and inheritance at a higher level of biological organisation. However, current evolutionary theory is poorly equipped to describe how these organisations change over evolutionary time and especially how that results in adaptive complexes at successive scales of organisation (the key problem is that evolution is self-referential, i.e. the products of evolution change the parameters of the evolutionary process). Here we first reinterpret the central open questions in these domains from a perspective that emphasises the common underlying themes. We then synthesise the findings from a developing body of work that is building a new theoretical approach to these questions by converting well-understood theory and results from models of cognitive learning. Specifically, connectionist models of memory and learning demonstrate how simple incremental mechanisms, adjusting the relationships between individually-simple components, can produce organisations that exhibit complex system-level behaviours and improve the adaptive capabilities of the system. We use the term “evolutionary connectionism” to recognise that, by functionally equivalent processes, natural selection acting on the relationships within and between evolutionary entities can result in organisations that produce complex system-level behaviours in evolutionary systems and modify the adaptive capabilities of natural selection over time. We review the evidence supporting the functional equivalences between the domains of learning and of evolution, and discuss the potential for this to resolve conceptual problems in our understanding of the evolution of developmental, ecological and reproductive organisations and, in particular, the major evolutionary transitions

The evolution of the cosmic molecular gas density

One of the last missing pieces in the puzzle of galaxy formation and evolution through cosmic history is a detailed picture of the role of the cold gas supply in the star-formation process. Cold gas is the fuel for star formation, and thus regulates the buildup of stellar mass, both through the amount of material present through a galaxy's gas mass fraction, and through the efficiency at which it is converted to stars. Over the last decade, important progress has been made in understanding the relative importance of these two factors along with the role of feedback, and the first measurements of the volume density of cold gas out to redshift 4, (the "cold gas history of the Universe") has been obtained. To match the precision of measurements of the star formation and black-hole accretion histories over the coming decades, a two orders of magnitude improvement in molecular line survey speeds is required compared to what is possible with current facilities. Possible pathways towards such large gains include significant upgrades to current facilities like ALMA by 2030 (and beyond), and eventually the construction of a new generation of radio-to-millimeter wavelength facilities, such as the next generation Very Large Array (ngVLA) concept.Comment: 7 pages, 2 figures, Science White paper submitted to Astro2020 Decadal Surve

On truth unpersistence: At the crossroads of epistemic modality and discourse

International audienceWe propose a semantic analysis of the particles afinal (European Portuguese) and alla fine (Italian) in terms of the notion of truth unpersistence, which combines both epistemic modality and constraints on discourse structure. We argue that the felicitous use of these modal particles requires that the truth of a proposition p* fail to persist through a temporal succession of epistemic states, where p* is incompatible with the proposition modified by afinal/alla fine, and that the interlocutors share knowledge of a previous epistemic attitude toward p*. We analyze two main cases, that of plan-related propositions and that of propositions without plans. We also discuss the connections between truth unpersistence and evidentiality

Social interaction, noise and antibiotic-mediated switches in the intestinal microbiota

The intestinal microbiota plays important roles in digestion and resistance against entero-pathogens. As with other ecosystems, its species composition is resilient against small disturbances but strong perturbations such as antibiotics can affect the consortium dramatically. Antibiotic cessation does not necessarily restore pre-treatment conditions and disturbed microbiota are often susceptible to pathogen invasion. Here we propose a mathematical model to explain how antibiotic-mediated switches in the microbiota composition can result from simple social interactions between antibiotic-tolerant and antibiotic-sensitive bacterial groups. We build a two-species (e.g. two functional-groups) model and identify regions of domination by antibiotic-sensitive or antibiotic-tolerant bacteria, as well as a region of multistability where domination by either group is possible. Using a new framework that we derived from statistical physics, we calculate the duration of each microbiota composition state. This is shown to depend on the balance between random fluctuations in the bacterial densities and the strength of microbial interactions. The singular value decomposition of recent metagenomic data confirms our assumption of grouping microbes as antibiotic-tolerant or antibiotic-sensitive in response to a single antibiotic. Our methodology can be extended to multiple bacterial groups and thus it provides an ecological formalism to help interpret the present surge in microbiome data.Comment: 20 pages, 5 figures accepted for publication in Plos Comp Bio. Supplementary video and information availabl