Physical Sciences and Mathematics Commons^™

Efficient Air Desulfurization Catalysts Derived From Pig Manure Liquefaction Char, Rajiv Wallace, Sundaramurthy Suresh, Elham H. Fini, Teresa Bandosz

Publications and Research

Biochar from the liquefaction of pig manure was used as a precursor of H2S desulfurization adsorbents. In its inorganic matter, it contains marked quantities of calcium, magnesium and iron, which are known as hydrogen sulfide oxidation catalysts. The char was used either as-received or mixed with 10% nanographite. The latter was added to increase both the content of the carbon phase and conductivity. ZnCl2 in two different ratios of char to an activation agent (1:1 and 1:2) was used to create the porosity in the carbon phase. The content of the later was between 18–45%. The activated samples adsorbed 144 …

Synthesis, Crystal Structure, And Photoluminescent Properties Of 3,3′,4,4′-Tetraethyl-5,5′-Divinyl-2,2′-Bipyrrole Derivatives, Toru Okawara, Reo Kawano, Hiroya Morita, Alan Finkelstein, Renjiro Toyofuku, Kanako Matsumoto, Kenji Takehara, Toshihiko Nagamura, Seiji Iwasa, Sanjai Kumar

Publications and Research

Photoluminescent divinylbipyrroles were synthesized from 3,3′,4,4′-tetraetyl-2,2′-bipyrrole-5,5′-dicarboxaldehyde and activated methylene compounds via aldol condensation.For mechanistic clarity, molecular structures of Meldrum’s acid- and 1,3-dimethylbarbituricacid-derived divinylbipyrroles were determined by single-crystal X-ray diffraction. Photoluminescentproperties of the synthesized divinylbipyrroles in dichloromethane were found to be dependent onthe presence of electron withdrawing groups at the vinylic terminal. The divinylbipyrroles derivedfrom malononitrile, Meldrum’s acid, and 1,3-dimethylbarbituric acid showed fluorescent peaks at553, 576, and 602 nm respectively. Computational studies indicated that the alkyl substituents on thebipyrrole 3 and 3′positions increased energy level of the highest occupied molecular orbital (HOMO)compared to the unsubstituted derivatives and provided rationale for the …

Ligand Modulation Of Sidechain Dynamics In A Wild-Type Human Gpcr, Lindsay D. Clark, Igor Dikiy, Karen Chapman, Karin Ej Rodstrom, James Aramini, Michael V. Levine, George Khelashvili, Soren Gf Rasmussen, Kevin H. Gardner, Daniel M. Rosenbaum

Publications and Research

GPCRs regulate all aspects of human physiology, and biophysical studies have deepened our understanding of GPCR conformational regulation by different ligands. Yet there is no experimental evidence for how sidechain dynamics control allosteric transitions between GPCR conformations. To address this deficit, we generated samples of a wild-type GPCR (A2AR) that are deuterated apart from 1H/13C NMR probes at isoleucine d1 methyl groups, which facilitated 1H/13C methyl TROSY NMR measurements with opposing ligands. Our data indicate that low [Na+] is required to allow large agonist-induced structural changes in A2AR, and that patterns of sidechain dynamics substantially differ between agonist (NECA) and …

Tumor Necrosis Factor Dynamically Regulates The Mrna Stabilome In Rheumatoid Arthritis Fibroblast-Like Synoviocytes, Konstantinos Loupasakis, David Kuo, Upneet K. Sokhi, Christopher Sohn, Bethany Syracuse, Eugenia G. Giannopoulou, Sung Ho Park, Hyelim Kang, Gunnar Rätsch, Lionel B. Ivashkiv, George D. Kalliolias

Publications and Research

During rheumatoid arthritis (RA), Tumor Necrosis Factor (TNF) activates fibroblast-like synoviocytes (FLS) inducing in a temporal order a constellation of genes, which perpetuate synovial inflammation. Although the molecular mechanisms regulating TNF-induced transcription are well characterized, little is known about the impact of mRNA stability on gene expression and the impact of TNF on decay rates of mRNA transcripts in FLS. To address these issues we performed RNA sequencing and genome-wide analysis of the mRNA stabilome in RA FLS. We found that TNF induces a biphasic gene expression program: initially, the inducible transcriptome consists primarily of unstable transcripts but progressively switches …

Species Identification Of Necrophagous Insect Eggs Based On Amino Acid Profile Differences Revealed By Direct Analysis In Real Time-High Resolution Mass Spectrometry, Justine E. Giffen, Jennifer Y. Rosati, Cameron M. Longo, Rabi A. Musah

Publications and Research

The colonization of decomposing remains by necrophagous insects such as blow flies is of forensic importance because the progression through the various stages of insect development can be correlated to time of death. The ability to infer this information hinges on accurate determination of the fly species that are associated with the entomological evidence collected. This evidence can include eggs, larvae, pupae, and puparial casings. Determination of the egg’s identity is particularly challenging because the eggs of multiple species are morphologically very similar. We report here that the species identity of fly eggs can be determined from their chemical fingerprint …

A Global Study Of Gpp Focusing On Light-Use Efficiency In A Random Forest Regression Model, Suhua Wei, Chuixiang Yi, Wei Fang, George Hendrey

Publications and Research

Light-use efficiency (LUE) is at the core of mechanistic modeling of global gross primary production (GPP). However, most LUE estimates in global models are satellite based and coarsely measured with emphasis on environmental variables. Others are from eddy covariance towers with much greater spatial and temporal data quality and emphasis on mechanistic processes, but in a limited number of sites. In this study, we conducted a comprehensive global study of tower-based LUE from 237 FLUXNET towers, and scaled up LUEs from in situ tower level to global biome level. We integrated the tower-based LUE estimates with key environmental and biological …

Conserved Patterns Of Integrated Developmental Plasticity In A Group Of Polyphenic Tropical Butterflies, Erik Van Bergen, Dave Osbaldeston, Ullasa Kondandaramaiah, Oskar Brattström, Kwaku Aduse-Poku, Paul M. Brakefield

Publications and Research

Background: Developmental plasticity is thought to have profound macro-evolutionary effects, for example, by increasing the probability of establishment in new environments and subsequent divergence into independently evolving lineages. In contrast to plasticity optimized for individual traits, phenotypic integration, which enables a concerted response of plastic traits to environmental variability, may affect the rate of local adaptation by constraining independent responses of traits to selection. Using a comparative framework, this study explores the evolution of reaction norms for a variety of life history and morphological traits across five related species of mycalesine butterflies from the Old World tropics.

Results: Our data …

Evolution Of Complex Target Selex To Identify Aptamers Against Mammalian Cell-Surface Antigens, Prabodhika R. Mallikaratchy

Publications and Research

The demand has increased for sophisticated molecular tools with improved detection limits. Such molecules should be simple in structure, yet stable enough for clinical applications. Nucleic acid aptamers (NAAs) represent a class of molecules able to meet this demand. In particular, aptamers, a class of small nucleic acid ligands that are composed of single-stranded modified/unmodified RNA/DNA molecules, can be evolved from a complex library using Systematic Evolution of Ligands by EXponential enrichment (SELEX) against almost any molecule. Since its introduction in 1990, in stages, SELEX technology has itself undergone several modifications, improving selection and broadening the repertoire of targets. This …

Rules And Mechanisms For Efficient Two-Stage Learning In Neural Circuits, Tiberiu Teşileanu, Bence Ölveczky, Vijay Balasubramanian

Publications and Research

Trial-and-error learning requires evaluating variable actions and reinforcing successful variants. In songbirds, vocal exploration is induced by LMAN, the output of a basal ganglia-related circuit that also contributes a corrective bias to the vocal output. This bias is gradually consolidated in RA, a motor cortex analogue downstream of LMAN. We develop a new model of such two-stage learning. Using stochastic gradient descent, we derive how the activity in ‘tutor’ circuits (e.g., LMAN) should match plasticity mechanisms in ‘student’ circuits (e.g., RA) to achieve efficient learning. We further describe a reinforcement learning framework through which the tutor can build its teaching …