TASK DEFINITION: In this task, you're given a paragraph from the research paper and your task is to generate a suitable title for the research paper based on the given paper. Under 100 words is a good title length.
PROBLEM: The Pneumonia Etiology Research for Child Health (PERCH) project is the largest multicountry etiology study of childhood pneumonia since the Board on Science and Technology in International Development studies of the 1980s. However, it is not the only recent or ongoing pneumonia etiology study, and even with seven sites, it cannot capture all epidemiologic settings in the developing world. Funding providers, researchers and policymakers rely on the best available evidence to strategically plan programs, new research directions and interventions. We aimed to describe the current landscape of recent pneumonia etiology studies in children under 5 years of age in the developed and developing world, as ascertained by a literature review of relevant studies with data since the year 2000 and a survey of researchers in the field of childhood pneumonia. We collected information on the study population, study design, case definitions, laboratory samples and methods and identified pathogens. A literature review identified 88 studies with child pneumonia etiology results. As of June 2010, our survey of researchers identified an additional 65 ongoing and recently completed child pneumonia etiology studies. This demonstrates the broad existing context into which the PERCH study must be placed. However, the landscape analysis also reveals a multiplicity of case definitions, levels of clinician involvement, facility types, specimen collection, and laboratory techniques. It reinforces the need for the standardization of methods and analyses for present and future pneumonia etiology studies in order to optimize their cumulative potential to accurately describe the microbial causes of childhood pneumonia. Each year, approximately 1.6 million children die from pneumonia [1]. The Pneumonia Etiology Research for Child Health (PERCH) study is the largest multisite study of childhood pneumonia since the Board of Science and Technology for International Development (BOSTID) studies were done in the 1980s [2] . The goal of PERCH is to identify the expected etiologies of pneumonia in 2015, a time when the burden of the major causes of bacterial pneumonia in the developing world, Streptococcus pneumoniae and Haemophilus influenzae type b (Hib), will likely be significantly reduced by widespread introduction and use of conjugate vaccines. Moreover, PERCH capitalizes upon new molecular diagnostic techniques that were not available 2 decades ago when the BOSTID studies were carried out. Another salient difference between PERCH and the BOSTID studies is that the 7 sites participating in PERCH will follow a highly standardized protocol, which includes standardization of enrollment criteria, specimen collection, and laboratory testing. Although PERCH is the largest multicountry, childhood pneumonia etiology study in developing countries that has been conducted in the past 2 decades, it is not the only contemporary pneumonia etiology study, and cannot capture the entire complexity of all epidemiologic settings. In recent years, many developed and developing country sites have initiated pneumonia studies that provide etiology data. These studies will

SOLUTION: A Literature Review and Survey of Childhood Pneumonia Etiology Studies: 2000-2010

PROBLEM: The complete nonstructural NS5 gene of Japanese encephalitis virus (JEV) was amplified and cloned into an expression vector. The NS5 protein was expressed in Escherichia coli and purified by His-tag based affinity chromatography. This recombinant NS5 protein exhibited RNA-dependent RNA polymerase (RdRp) activity in vitro in the absence of other viral or cellular factors. The RNA polymerase activity was dependent on divalent cations, and Mn 2 was found to be 20 times more effective than Mg 2 in coordinating the catalytic reaction of RdRp, while Ca 2 inhibited enzyme activity. The optimal reaction conditions for the in vitro RdRp reaction were established. Characterization of the RdRp reaction products demonstrated that the JEV NS5 protein can initiate RNA synthesis through a de novo initiation mechanism in our in vitro reaction system. Comparing the efficiency of different RNA templates, we found that JEV NS5 protein was more efficient in using negative-strand RNA templates, indicating that the JEV NS5 protein is in-volved in regulating the ratio of positive-to negativestrand RNA. Four amino acid sequence motifs crucial for RdRp activity were also identified using site-directed mutagenesis analysis. All substitutions of the conserved residues within these motifs led to a complete inactivation or severe loss of enzyme activity.

SOLUTION: Identification and characterization of RNA-dependent RNA polymerase activity in recombinant Japanese encephalitis virus NS5 protein

PROBLEM: Mutation rates can evolve through genetic drift, indirect selection due to genetic hitchhiking, or direct selection on the physicochemical cost of high fidelity. However, for many systems, it has been difficult to disentangle the relative impact of these forces empirically. In RNA viruses, an observed correlation between mutation rate and virulence has led many to argue that their extremely high mutation rates are advantageous because they may allow for increased adaptability. This argument has profound implications because it suggests that pathogenesis in many viral infections depends on rare or de novo mutations. Here, we present data for an alternative model whereby RNA viruses evolve high mutation rates as a byproduct of selection for increased replicative speed. We find that a poliovirus antimutator, 3D G64S , has a significant replication defect and that wild-type (WT) and 3D G64S populations have similar adaptability in 2 distinct cellular environments. Experimental evolution of 3D G64S under selection for replicative speed led to reversion and compensation of the fidelity phenotype. Mice infected with 3D G64S exhibited delayed morbidity at doses well above the lethal level, consistent with attenuation by slower growth as opposed to reduced mutational supply. Furthermore, compensation of the 3D G64S growth defect restored virulence, while compensation of the fidelity phenotype did not. Our data are consistent with the kinetic proofreading model for biosynthetic reactions and suggest that speed is more important than accuracy. In contrast with what has been suggested for many RNA viruses, we find that within-host spread is associated with viral replicative speed and not standing genetic diversity. Why organisms have different mutation rates is a longstanding question in evolutionary biology. The polymerases of RNA viruses generally lack proofreading activity and exhibit extremely high mutation rates. Because most mutations are deleterious and mutation PLOS Biology | https://doi.org/10.1371/journal.pbio.Citation: Fitzsimmons WJ, Woods RJ, McCrone JT, Woodman A, Arnold JJ, Yennawar M, et al. (2018) A speed-fidelity trade-off determines the mutation rate and virulence of an RNA virus. PLoS Biol 16(6): e2006459. https://doi.The funder had no role in study design, data collection and analysis, decision to publish, or preparation of rates are typically tuned by natural selection, we asked why RNA viruses haven't evolved a polymerase with a lower mutation rate. We used experimental evolution and a murine infection model to show that RNA virus mutation rates may actually be too high and are not necessarily adaptive. Rather, our data indicate that viral mutation rates have evolved to be higher as a result of selection for viruses with faster replication kinetics. We suggest that viruses have high mutation rates, not because they facilitate adaptation but because it is hard to be both fast and accurate and these viruses have prioritized speed over fidelity. Speed-fidelity trade-off PLOS Biology | https://doi.org/10.1371/journal.pbio.

SOLUTION:
A speed-fidelity trade-off determines the mutation rate and virulence of an RNA virus