166 results match your criteria: "Knox College.[Affiliation]"

Probing the stability and mechanism for folding of the GrpE1-112 tetrameric deletion mutant of the GrpE protein from E. coli.

Biochem Biophys Res Commun

April 2012

Department of Chemistry and The Program in Biochemistry, Knox College, 2 East South St., Galesburg, IL 61401, USA.

Insight into the stability and folding of oligomeric proteins is essential to the understanding of protein folding, especially since the majority of proteins found in nature are oligomeric. A deletion mutant of the GrpE protein from Escherichia coli, that contains the first 112 residues (GrpE1-112) of 197 total, is an oligomeric protein forming a tetrameric structure. A four-helix bundle structure is formed via the interaction of an α-helix (22 amino acids in length) from each monomer.

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Considering the role of conditioning in sexual orientation.

Arch Sex Behav

February 2012

Department of Psychology, Knox College, Galesburg, IL 61401-4999, USA.

The effects of learning on sexual orientation are rarely addressed in the literature. At the very least, such processes provide a means of elaborating upon orientation predispositions. Some aspects of our mates may inherently elicit a sexual response, but other attributes do so only after sexual experience with them.

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Field conditioning of sexual arousal in humans.

Socioaffect Neurosci Psychol

April 2014

Knox College, Department of Psychology, Galesburg, IL, USA.

Background: Human sexual classical conditioning effects are less robust compared with those obtained in other animals. The artificiality of the laboratory environment and/or the unconditioned stimulus (US) used (e.g.

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Conservation and divergence in plant microRNAs.

Plant Mol Biol

September 2012

Department of Biology, Knox College, Galesburg, IL 61401, USA.

MicroRNAs (miRNAs) are a class of small, non-coding RNAs that regulate gene expression in eukaryotic cells. The past decade has seen an explosion in our understanding of the sets of miRNA genes encoded in the genomes in different species of plants and the mechanisms by which miRNAs interact with target RNAs. A subset of miRNA families (and their binding sites in target RNAs) are conserved between angiosperms and basal plants, suggesting they predate the divergence of existing lineages of plants.

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A new nuclear quadrupole double resonance spectrometer based on a commercial superconducting quantum interference device (SQUID) setup (a Magnetic Property Measurement System (MPMS) from Quantum Design) is described. The experiment involves the indirect detection of pure quadrupole resonances (PQR) of a dilute spin system via the direct SQUID detected NMR of an abundant spin system. The experiment is conducted at low (3-20 K) temperatures and the magnetic field is cycled between a high (5.

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Insight into protein stability and folding remains an important area for protein research, in particular protein-protein interactions and the self-assembly of homodimers. The GrpE protein from Escherichia coli is a homodimer with a four-helix bundle at the dimer interface. Each monomer contributes a helix-loop-helix to the bundle.

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Four novel spirooxazacamphorsultam derivatives.

Acta Crystallogr C

December 2010

Knox College, Department of Chemistry, 2 E. South Street, Galesburg, Illinois 61401, USA.

The chiral compounds (6aS,9S,10aR)-11,11-dimethyl-5,5-dioxo-2,3,8,9-tetrahydro-6H-6a,9-methanooxazaolo[2,3-i][2,1]benzisothiazol-10(7H)-one, C(12)H(17)NO(4)S, (1), (7aS,10S,11aR)-12,12-dimethyl-6,6-dioxo-3,4,9,10-tetrahydro-7H-7a,10-methano-2H-1,3-oxazino[2,3-i][2,1]benzisothiazol-11(8H)-one, C(13)H(19)NO(4)S, (2), (6aS,9S,10R,10aR)-11,11-dimethyl-5,5-dioxo-2,3,7,8,9,10-hexahydro-6H-6a,9-methanooxazolo[2,3-i][2,1]benzisothiazol-10-ol, C(12)H(19)NO(4)S, (3), and (7aS,10S,11R,11aR)-12,12-dimethyl-6,6-dioxo-3,4,8,9,10,11-hexahydro-7H-7a-methano-2H-[1,3]oxazino[2,3-i][2,1]benzisothiazol-11-ol, C(13)H(21)NO(4)S, (4), consist of a camphor core with a five-membered spirosultaoxazolidine or six-membered spirosultaoxazine, as both their keto and hydroxy derivatives. In each structure, the molecules are linked via hydrogen bonding to the sulfonyl O atoms, forming chains in the unit-cell b-axis direction. The chains interconnect via weak C-H.

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Genetic testing likelihood: the impact of abortion views and quality of life information on women's decisions.

J Genet Couns

April 2011

Department of Psychology, Knox College, 2 East South Street, Box 120, Galesburg, IL 61401, USA.

Little is known about factors predicting the likelihood of choosing genetic testing in college aged women versus older women, including knowledge of quality of life (QOL) associated with a disorder. Using vignettes with female college students (Experiment 1: n=257, mean age=19.70 yrs) and female faculty/staff/alumni (Experiment 2: n (nulliparous)=83, mean age=30.

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Object appearance and picture-specific viewpoint are not integrated in long-term memory.

Q J Exp Psychol (Hove)

June 2010

Department of Psychology, Knox College, Galesburg, IL 61401, USA.

Previous work has demonstrated that visual long-term memory (VLTM) stores detailed information about object appearance. The current experiments investigate whether object appearance information in VLTM is integrated within representations that contain picture-specific viewpoint information. In three experiments using both incidental and intentional encoding instructions, participants were unable to perform above chance on recognition tests that required recognizing the conjunction of object appearance and viewpoint information (Experiments 1a, 1b, 2, and 3).

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Prediction of plant miRNA genes.

Methods Mol Biol

January 2010

Department of Biology, Knox College, Galesburg, IL, USA.

This chapter presents procedures for the computational identification of plant miRNA genes. In the first procedure, homologs of known miRNAs are identified in a database of genomic or cDNA sequence. In the second procedure, previously unidentified miRNA families are predicted through the analysis of secondary structure, evolutionary conservation, and targeting potential.

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An examination was made of the effect of electrode polishing on the direct pulsed amperometric detection (PAD) and indirect PAD response to penicillin G. The polishing procedure produced a temporary loss of sensitivity for both types of PAD, which over time relaxed back to higher levels. A temporary increase in the electrode kinetics can be observed as well, particularly for a PAD waveform in the crossover region between direct and indirect PAD.

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A mixture of seven penicillins was separated on a C-8 column and detected using pulsed amperometric detection (PAD). Due to the polarity range of the penicillin mixture, a gradient program was necessary to produce a reasonable separation, causing some baseline shifting. Application of a flow program, where the solvent flow rate is varied within the separation, was also examined, and found to cause only a small shift in baseline response for PAD.

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Structural and Physical Characterization of (Nitrato)iron(III) Porphyrinates [Fe(por)(NO(3))] - Variable Coordination of Nitrate.

Polyhedron

October 2007

Contribution from The Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, and Department of Physics, Knox College, Galesburg, Illinois, 61401.

We report the X-ray crystal structures of two different iron(III) porphyrinates: [Fe(OEP)(NO(3))] and [Fe(TPP)(NO(3))]. The first complex has the nitrate ion coordinated by a single oxygen atom while the second derivative has the nitrate coordinated in a symmetric bidentate fashion. This latter structure is a redetermination that shows some differences from an earlier structure; the difference appears to be the result of an unrecognized nitrate ion disorder in the earlier structure determination.

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It has been suggested that birds prefer to use a particular eye while learning to detect cryptic prey and that this eye preference enhances foraging performance. European starlings (Sturnus vulgaris) with the left, right, or both eyes available learned to detect inconspicuous cues associated with the presence of hidden prey. Acquisition scores were not significantly different between left and right-eyed birds; however, performance in the binocular condition was significantly higher than in the two monocular conditions.

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Scene structure enhances change detection.

Q J Exp Psychol (Hove)

April 2008

Department of Psychology, Knox College, Box K60, Galesburg, IL 61401, USA.

Theories of objects recognition, scene perception, and neural representation of scenes imply that jumbling a coherent scene should reduce change detection. However, evidence from the change detection literature questions whether jumbling affects change detection. The experiments reported here demonstrate that jumbling does, in fact, reduce change detection.

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On Spin Hamiltonian Fits to Mössbauer Spectra of High-Spin Fe(II) Porphyrinate Systems.

Hyperfine Interact

June 2006

Department of Physics, Knox College, Galesburg, Illinois 61401, USA; E-mail:

Fits to Mössbauer spectra of high-spin iron(II) porphyrinates have been applied to the Fe(II) model compounds octaethylporphyrin(1,2-dimethylimidazole) and tetra-paramethoxyporphyrin(1,2-dimethylimidazole). Mössbauer spectra have been measured on these compounds at 4.2 K in large applied fields.

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In this paper we present two compatible hypotheses to explain interest in celebrity gossip. The Learning Hypothesis explains interest in celebrity gossip as a by-product of an evolved mechanism useful for acquiring fitness-relevant survival information. The Parasocial Hypothesis sees celebrity gossip as a diversion of this mechanism, which leads individuals to misperceive celebrities as people who are part of their social network.

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The GrpE protein from E. coli is a homodimer with an unusual structure of two long paired alpha-helices from each monomer interacting in a parallel arrangement to form a "tail" at the N-terminal end. Using site-directed mutagenesis, we show that there is a key electrostatic interaction involving R57 (mediated by a water molecule) that provides thermal stability to this "tail" region.

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Heat shock in barley aleurone layers induces heat shock protein synthesis and suppresses secretory protein synthesis by selectively destabilizing their mRNAs. In addition, the endoplasmic reticulum (ER) membranes upon which secretory protein mRNAs are translated become vesiculated during heat shock, leading to the hypothesis that ER dissociation and targeted mRNA destabilization are linked mechanistically. Supporting this, ER can be heat adapted, and heat-adapted ER has higher levels of fatty acid saturation in membrane phospholipids which do not vesiculate upon heat shock.

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We tested whether interacting with a gun increased testosterone levels and later aggressive behavior. Thirty male college students provided a saliva sample (for testosterone assay), interacted with either a gun or a children's toy for 15 min, and then provided another saliva sample. Next, subjects added as much hot sauce as they wanted to a cup of water they believed another subject would have to drink.

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Participants were 57 U.S. college students and 56 Polish university students and copper mine workers who judged the intimacy of 9 hypothetical relationships and also rated the intensity of their relationships with a best friend, a friend, and an acquaintance on the Friendship Intensity Measurement Scale (FIMS; T.

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Human contact in the shelter may lessen effects of change in environment and smooth transition into a home. Training can increase a dog's interaction with people in a shelter environment. Experiments were conducted to determine how rapidly shelter dogs learn to sit, if the dogs can retain sitting behavior over time, and if sitting transfers to novel locations and people.

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Electronic configuration assignment and the importance of low-lying excited states in high-spin imidazole-ligated iron(II) porphyrinates.

J Am Chem Soc

April 2005

Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, and Department of Physics, Knox College, Galesburg, Illinois 61401, USA.

The synthesis and characterization of six new high-spin deoxymyoglobin models (imidazole(tetraarylporphyrinato)iron(II)) are described. These have been intensively studied by temperature-dependent Mossbauer spectroscopy from 295 to 4.2 K.

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108 Spanish university students (55 men, 53 women) from the University of Barcelona and 111 American college students (51 men, 60 women) from a midwestern liberal arts college responded to Fallon and Rozin's 1985 figure drawings used to measure perceptions of body image. All students were between the ages of 18 and 24 years. Women viewed themselves as being significantly larger than men perceived themselves to be, and women also desired a significantly thinner body for themselves than did men.

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