Institution
Pennsylvania State University
Education•State College, Pennsylvania, United States•
About: Pennsylvania State University is a education organization based out in State College, Pennsylvania, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 79763 authors who have published 196876 publications receiving 8318601 citations. The organization is also known as: Penn State & PSU.
Topics: Population, Poison control, Dielectric, Context (language use), Galaxy
Papers published on a yearly basis
Papers
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TL;DR: In this article, an analytical expression for the optimal power flow from a rectified piezoelectric device is derived, and an energy harvesting circuit consisting of an AC-DC rectifier with an output capacitor, an electrochemical battery, and a switch-mode DC-DC converter that controls the energy flow into the battery.
Abstract: This paper describes an approach to harvesting electrical energy from a mechanically excited piezoelectric element. A vibrating piezoelectric device differs from a typical electrical power source in that it has a capacitive rather than inductive source impedance, and may be driven by mechanical vibrations of varying amplitude. An analytical expression for the optimal power flow from a rectified piezoelectric device is derived, and an "energy harvesting" circuit is proposed which can achieve this optimal power flow. The harvesting circuit consists of an AC-DC rectifier with an output capacitor, an electrochemical battery, and a switch-mode DC-DC converter that controls the energy flow into the battery. An adaptive control technique for the DC-DC converter is used to continuously implement the optimal power transfer theory and maximize the power stored by the battery. Experimental results reveal that use of the adaptive DC-DC converter increases power transfer by over 400% as compared to when the DC-DC converter is not used.
1,072 citations
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TL;DR: Sequence analysis of two megabases in 26 structural genes or loci in strains recovered globally discovered a striking reduction of silent nucleotide substitutions compared with other human bacterial pathogens, indicating that M. tuberculosis is evolutionarily young and has recently spread globally.
Abstract: One-third of humans are infected with Mycobacterium tuberculosis, the causative agent of tuberculosis. Sequence analysis of two megabases in 26 structural genes or loci in strains recovered globally discovered a striking reduction of silent nucleotide substitutions compared with other human bacterial pathogens. The lack of neutral mutations in structural genes indicates that M. tuberculosis is evolutionarily young and has recently spread globally. Species diversity is largely caused by rapidly evolving insertion sequences, which means that mobile element movement is a fundamental process generating genomic variation in this pathogen. Three genetic groups of M. tuberculosis were identified based on two polymorphisms that occur at high frequency in the genes encoding catalase-peroxidase and the A subunit of gyrase. Group 1 organisms are evolutionarily old and allied with M. bovis, the cause of bovine tuberculosis. A subset of several distinct insertion sequence IS6110 subtypes of this genetic group have IS6110 integrated at the identical chromosomal insertion site, located between dnaA and dnaN in the region containing the origin of replication. Remarkably, study of ≈6,000 isolates from patients in Houston and the New York City area discovered that 47 of 48 relatively large case clusters were caused by genotypic group 1 and 2 but not group 3 organisms. The observation that the newly emergent group 3 organisms are associated with sporadic rather than clustered cases suggests that the pathogen is evolving toward a state of reduced transmissability or virulence.
1,072 citations
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TL;DR: The present day value of honey bees is highlighted, followed by a detailed description of some of the historical and present day factors that influence honey bee populations, with particular emphasis on colony populations in Europe and the United States.
1,069 citations
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TL;DR: Learning and performance goal orientations, two motivational orientations that guide salespeople's behavior, are related to working smart and hard as discussed by the authors, which is defined as the engagement in act...
Abstract: Learning and performance goal orientations, two motivational orientations that guide salespeople's behavior, are related to working smart and hard. Working smart is defined as the engagement in act...
1,068 citations
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TL;DR: A case study for the enzyme dihydrofolate reductase provides evidence for coupled networks of predominantly conserved residues that influence the protein structure and motion that have important implications for the origin and evolution of enzymes, as well as for protein engineering.
Abstract: The seminal hypotheses proposed over the years for enzymatic catalysis are scrutinized. The historical record is explored from both biochemical and theoretical perspectives. Particular attention is given to the impact of molecular motions within the protein on the enzyme's catalytic properties. A case study for the enzyme dihydrofolate reductase provides evidence for coupled networks of predominantly conserved residues that influence the protein structure and motion. Such coupled networks have important implications for the origin and evolution of enzymes, as well as for protein engineering.
1,068 citations
Authors
Showing all 80524 results
Name | H-index | Papers | Citations |
---|---|---|---|
Robert Langer | 281 | 2324 | 326306 |
Zhong Lin Wang | 245 | 2529 | 259003 |
Donald P. Schneider | 242 | 1622 | 263641 |
David J. Hunter | 213 | 1836 | 207050 |
Robert M. Califf | 196 | 1561 | 167961 |
Martin White | 196 | 2038 | 232387 |
Eric J. Topol | 193 | 1373 | 151025 |
Charles A. Dinarello | 190 | 1058 | 139668 |
Jing Wang | 184 | 4046 | 202769 |
Dennis S. Charney | 179 | 802 | 122408 |
David Haussler | 172 | 488 | 224960 |
Chad A. Mirkin | 164 | 1078 | 134254 |
Ian A. Wilson | 158 | 971 | 98221 |
David Cella | 156 | 1258 | 106402 |
Jay Hauser | 155 | 2145 | 132683 |