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Solar Neutrinos: Where We Are, What We Need  [PDF]
John N. Bahcall
Physics , 1998, DOI: 10.1016/S0375-9474(98)00013-X
Abstract: This talk compares standard model predictions with the results of solar neutrino experiments. Here `standard model' means the combined standard model of minimal electroweak theory plus a standard solar model. I emphasize the importance of recent analyses in which the neutrino fluxes are treated as free parameters, independent of any constraints from solar models, and the stunning agreement between the predictions of standard solar models and helioseismological measurements. In order to interpret solar neutrino experiments more accurately in terms of fundamental physics and astronomy, we need improved improved nuclear physics data. I describe the five most important nuclear physics problems whose solution is required for understanding the precise implications of solar neutrino experiments.
Solar Neutrinos: Where We Are, Where We Are Going  [PDF]
John N. Bahcall
Physics , 1995, DOI: 10.1086/177624
Abstract: This talk answers a series of questions. Why study solar neutrinos? What does the combined standard model (solar plus electroweak) predict for solar neutrinos? Why are the calculations of neutrino fluxes robust? What are the three solar neutrino problems? What have we learned in the first thirty years of solar neutrino research? For the next decade, what are the most important solvable problems in the physics of solar neutrinos? What are the most important problems in the astrophysics of solar neutrinos?
The first decade of microbial genomics: what have we learned and where are we going next?
David A Rasko, Emmanuel F Mongodin
Genome Biology , 2005, DOI: 10.1186/gb-2005-6-9-341
Abstract: It is now a decade since the first microbial genome was sequenced. Although genomics is still in its infancy and the best is (hopefully!) still to come, amazing strides have been made since the completion in 1995 of the first genome sequence of a free-living organism, the bacterium Haemophilus influenzae. Just ten years later, 261 microbial genomes have been completed and an additional 669 are in progress. We have progressed from sequencing a single bacterial isolate, assuming that it was an adequate reference for that species, to metagenomics - sequencing an entire microbial community. We are just starting to discover the complexity and dynamic nature of the microbial world, which raises further questions. For example, what is a bacterial species? How many isolates need to be sequenced to capture the diversity of a single species? During the course of the recent International Conference on Microbial Genomics held in Canada, the question of "what is a bacterial species" was raised and discussed on many occasions. As pointed out by W. Ford Doolittle (Dalhousie University, Halifax, Canada), the notion of a bacterial species is classically defined as a "uniform and stable way for naming groups of similar bacteria". On the genetic level, it is well accepted that two isolates are part of the same species if their 16S rRNA genes share at least 98% identity. This definition is not, however, a good predictor of ecological and phenotypic differences. Furthermore, recombination and gene transfer among prokaryotes, as revealed by genomic, and more recently metagenomic, studies, create further difficulties in describing a microbial species. The concept of a bacterial species appears to take different forms depending on the scientific perspective. Genomic and clinical examinations of Escherichia coli and Shigella species clearly reveal significant differences, leading to sub-classification based on gene content and disease presentation; comparison of the 16S rRNA sequences, howe
The landscape of knowledge translation interventions in cancer control: What do we know and where to next? A review of systematic reviews
Melissa C Brouwers, Kimberly Garcia, Julie Makarski, Lubna Daraz, of the Evidence Expert Panel, of the KT for Cancer Control in Canada Project Research Team
Implementation Science , 2011, DOI: 10.1186/1748-5908-6-130
Abstract: Using three databases, we conducted a search and identified English-language systematic reviews published between 2005 and 2010 that targeted consumer, professional, organizational, regulatory, or financial interventions, tested exclusively or partially in a cancer context (primary focus); generic or non-cancer-specific reviews were also considered. Data were extracted, appraised, and analyzed by members of the research team, and research ideas to advance the field were proposed.Thirty-four systematic reviews providing 41 summaries of evidence on 19 unique interventions comprised the evidence base. AMSTAR quality ratings ranged between 2 and 10. Team members rated most of the interventions as promising and in need of further research, and 64 research ideas were identified.While many interventions show promise of effectiveness in the cancer-control context, few reviews were able to conclude definitively in favor of or against a specific intervention. We discuss the complexity of implementation research and offer suggestions to advance the science in this area.Innovations in screening and early detection, development of effective treatment interventions, and strategies to improve quality of life have emerged from primary studies, and systematic reviews of these studies, in cancer control [1-9]. These advancements have the capacity to reduce mortality and morbidity from disease. However, optimizing these advancements requires their appropriate application, a goal that is often difficult to achieve [10,11]. Understanding what are the most effective and promising interventions is warranted to ensure that the appropriate options are chosen and incorporated into implementation plans and prioritized for future research studies. The analysis of studies examining the effectiveness of implementation interventions is a key component to an overall knowledge translation (KT) research agenda [12].The purpose of our study was to conduct a review of systematic reviews to better unde
Solar Neutrinos: What Next?  [PDF]
John N. Bahcall
Physics , 2000, DOI: 10.1063/1.1361728
Abstract: I summarize the current state of solar neutrino research and then give my answer to the question: What should we do next?
Solar Neutrinos: Where We Are  [PDF]
John Bahcall
Physics , 1997,
Abstract: This talk compares standard model predictions for solar neutrino experiments with the results of actual observations. Here `standard model' means the combined standard model of minimal electroweak theory plus a standard solar model. I emphasize the importance of recent analyses in which the neutrino fluxes are treated as free parameters, independent of any constraints from solar models, and the stunning agreement between the predictions of standard solar models and helioseismological measurements.
Solar Neutrinos: Where We Are, Where We Are Going  [PDF]
John N. Bahcall
Physics , 1994,
Abstract: There are four important facts about solar neutrinos. They are listed in order of importance in this abstract and discussed more in the text of the talk. First, solar neutrinos have been detected in four experiments with approximately the energies and fluxes predicted by the standard solar model, confirming the hypothesis that the energy source for the solar luminosity is the fusion of light elements. Second, the measured event rates are significantl less than the event rates predicted by the combined standard solar and electroweak models in all four experiments. Third, a comparison of the event rates measured in the chlorine experiment (threshold 0.8 Mev) and the neutrino-electron scattering experiment (Kamiokande II, threshold 7.5 MeV) indicates that the deficiency of electron-type neutrinos at the earth is energy dependent, if the rates and the uncertainties in both experiments have been correctly understood. The inference that the deficiency is energy-dependent conflicts with the simplest version of standard electroweak theory. Fourth, experiments are being constructed that have the capabilities to determine conclusively if new neutrino physics is required.
Astrophysical neutrinos: 20th Century and Beyond  [PDF]
John N. Bahcall
Physics , 2000, DOI: 10.1142/S0217751X01005948
Abstract: I summarize the first four decades of solar neutrino research and suggest what may be possible to learn with extragalactic neutrinos and with solar neutrinos in the next decade.
Solar Neutrinos: What We Have Learned  [PDF]
John N. Bahcall
Physics , 1993, DOI: 10.1007/BFb0118706
Abstract: The four operating solar neutrino experiments confirm the hypothesis that the energy source for solar luminosity is hydrogen fusion. However, the measured rate for each of the four solar neutrino experiments differs significantly (by factors of 2.0 to 3.5) from the corresponding theoretical prediction that is based upon the standard solar model and the simplest version of the standard electroweak theory. If standard electroweak theory is correct, the energy spectrum for \b8 neutrinos created in the solar interior must be the same (to one part in $10^5$) as the known laboratory \b8 neutrino energy spectrum. Direct comparison of the chlorine and the Kamiokande experiments, both sensitive to \b8 neutrinos, suggests that the discrepancy between theory and observations depends upon neutrino energy, in conflict with standard expectations. Monte Carlo studies with 1000 implementations of the standard solar model confirm that the chlorine and the Kamiokande experiments cannot be reconciled unless new weak interaction physics changes the shape of the \b8 neutrino energy spectrum. The results of the two gallium solar neutrino experiments strengthen the conclusion that new physics is required and help determine a relatively small allowed region for the MSW neutrino parameters.
Process Supply Chains Management - Where are we ? Where to go next ?  [PDF]
Ana P. Barbosa-Povoa
Frontiers in Energy Research , 2014, DOI: 10.3389/fenrg.2014.00023
Abstract: Commonly Process Industries Supply Chains deal with chemical process based networks involving suppliers, producers, warehouses, retailers and distributors. More recently reverse logistics activities started to be also considered as part of such networks, being these responsible for incorporating into the forward chains non-conforming/ end of life products through recovering processes. This supports the exploration of the waste to value concept within the supply chains while addressing important environmental issues. The result of such behavior has increased the already complex management of such systems challenging the development of decision supporting tools that can help the related decision process. In this paper we address this need and analyse the more relevant published works that contribute to this goal while identifying the classes of problems that have been solved and which are the new trends in the area. We finalize this article by drawing some conclusions where we discuss advances performed and recognized challenges for the future.
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