Interleukin-13 Genetic Variants, Household Carpet Use and Childhood Asthma

10.1371/journal.pone.0051970PLoS ONE81

The Effect Of Refolding Conditions On The Protein Solubility Recovered From Inclusion Bodies

Recombinant proteins are expressed as inclusion bodies in bacterial enriched native-like secondary structure and thus give a great potential in biotechnological utilities. However, the quality of soluble proteins recovered from inclusion bodies is questionable because the refolded protein with wrong conformation will assemble to form aggregates. In this study, enhanced green fluorescent protein-inclusion bodies was used as the model protein to investigate the effects of protein concentration and purity on protein refolding. Three different types of solubized enhanced green fluorescent protein-inclusion bodies were refolded which were solubized inclusion bodies with cell debris, solubized inclusion bodies with detergent washing, and purified solubized inclusion bodies using preparative native urea-polyacrylamide gel electrophoresis. For the first and second conditions, the solubized enhanced green fluorescent protein-inclusion bodies were refolded at a high protein concentration and low protein purity environment. Polyacrylamide gel images show the refolded protein changed in conformation and increased in size when the solubized inclusion bodies underwent various refolding periods. Meanwhile, the refolded protein under the third refolding condition has a correct protein conformation and achieved the highest refolding yield. Studying the effects of refolding conditions using different types of solubized inclusion bodies may provide researchers with possible approaches to avoid soluble aggregates formation

A Study of Perturbations in Structure and Elastic Modulus of Bone Microconstituents Using Bimodal Amplitude Modulated-Frequency Modulated Atomic Force Microscopy

This document is the unedited Author’s version of a Submitted Work that was subsequently accepted for publication in ACS Biomaterials Science and Engineering , copyright © American Chemical Society after peer review. To access the final edited and published work see https://pubs.acs.org/doi/10.1021/acsbiomaterials.8b01087The authors thank the financial support by National University of Singapore through the Eng-Med Seed Grant (R-265-000-532- 112) and Ministry of Education, Singapore, through National University of Singapore on Academic Research Funding (AcRF) R-265-000-495-112. Y.S. thanks the support of research scholarship from National University of Singapore

Determination of the Gamow-Teller Quenching Factor from Charge Exchange Reactions on 90Zr

Double differential cross sections between 0-12 degrees were measured for the 90Zr(n,p) reaction at 293 MeV over a wide excitation energy range of 0-70 MeV. A multipole decomposition technique was applied to the present data as well as the previously obtained 90Zr(p,n) data to extract the Gamow-Teller (GT) component from the continuum. The GT quenching factor Q was derived by using the obtained total GT strengths. The result is Q=0.88+/-0.06 not including an overall normalization uncertainty in the GT unit cross section of 16%.Comment: 11 papes, 4 figures, submitted to Physics Letters B (accepted), gzipped tar file, changed content

Predictions for s-Wave and p-Wave Heavy Baryons from Sum Rules and Constituent Quark Model (I): Strong Interactions

We study the strong interactions of the L=1 orbitally excited baryons with one heavy quark in the framework of the Heavy Hadron Chiral Perturbation Theory. To leading order in the heavy mass expansion, the interaction Lagrangian describing the couplings of these states among themselves and with the ground state heavy baryons contains 46 unknown couplings. We derive sum rules analogous to the Adler-Weisberger sum rule which constrain these couplings and relate them to the couplings of the s-wave heavy baryons. Using a spin 3/2 baryon as a target, we find a sum rule expressing the deviation from the quark model prediction for pion couplings to s-wave states in terms of couplings of the p-wave states. In the constituent quark model these couplings are related and can be expressed in terms of only two reduced matrix elements. Using recent CLEO data on $\Sigma_c^{*}$ and $\Lambda_{c1}^+$ strong decays, we determine some of the unknown couplings in the chiral Lagrangian and the two quark model reduced matrix elements. Specific predictions are made for the decay properties of all L=1 charmed baryons.Comment: 50 pages, REVTeX with 4 included figures; predictions for additional decay modes included; 1 reference adde

Interaction of Wilson loops in confining vacuum

Nonperturbative and perturbative interaction mechanisms of Wilson loops in gluodynamics are studied within the background field formalism. The first one operates when distance between minimal surfaces of the loops is small and may be important for sea quark effects and strong decay processes. The second mechanism -- perturbative interaction in nonperturbative confining background is found to be physically dominant for all loop configurations characteristic of scattering process. It reduces to perturbative gluon exchanges at small distances, while at larger distances it corresponds to the t-channel exchange of (reggeized) glueball states. Comparison to other approaches is made and possible physical applications are discussed.Comment: LaTeX, 25 pages, 5 EPS-figure

Unified approach to photo and electro-production of mesons with arbitrary spins

A new approach to identify the independent amplitudes along with their partial wave multipole expansions, for photo and electro-production is suggested,which is generally applicable to mesons with arbitrary spin-parity. These amplitudes facilitate direct identification of different resonance contributions.Comment: 11 page

Food waste hydrolysate as fermentation medium: Comparison of pre-treatment methods

Value-adding food/kitchen wastes have become a trend in view of the urge of reducing environmental impact and better exploitation of resources for a sustainable circular economy. As the wastes are full of nutrition but exist in various complex and simple forms, pre-treatment is required. The choice of method greatly depends on the type and nature of the waste; thus, comparison study is necessary. The objective of this study is to compare the pretreatment methods that are effective to treat kitchen waste in order to turn it into rich fermentation medium for subsequent value added compounds production. Three pretreatment methods were examined, i.e., hydrothermal, alkaline and enzymatic. Food to water ratio, temperature and holding time effects were studied in the hydrothermal pretreatment. While the effect of types of alkaline, alkaline concentration and reaction temperature were investigated in alkaline pretreatment. In enzymatic pretreatment, the effect of enzyme amount, incubation temperature, reaction time and pH were explored. The amount of nutrients hydrolyzed were determined through phenol-sulphuric acid (carbohydrate), Bradford (protein) and Bligh & Dyer (lipid) methods. The rough energy and chemical costs involved in each method was also compared. The results revealed that hydrothermal pretreatment and enzymatic pretreatment were comparable in terms of the ability to solubilize nutrients from the complex food wastes. Alkaline pretreatment was the cheapest method, but poor in nutrients extraction. Hence, hydrothermal pretreatment is the best pretreatment method to prepare nutritive food waste hydrolysate at a lower cost with acceptable performance

Modal Analysis and Coupling in Metal-Insulator-Metal Waveguides

This paper shows how to analyze plasmonic metal-insulator-metal waveguides using the full modal structure of these guides. The analysis applies to all frequencies, particularly including the near infrared and visible spectrum, and to a wide range of sizes, including nanometallic structures. We use the approach here specifically to analyze waveguide junctions. We show that the full modal structure of the metal-insulator-metal (MIM) waveguides--which consists of real and complex discrete eigenvalue spectra, as well as the continuous spectrum--forms a complete basis set. We provide the derivation of these modes using the techniques developed for Sturm-Liouville and generalized eigenvalue equations. We demonstrate the need to include all parts of the spectrum to have a complete set of basis vectors to describe scattering within MIM waveguides with the mode-matching technique. We numerically compare the mode-matching formulation with finite-difference frequency-domain analysis and find very good agreement between the two for modal scattering at symmetric MIM waveguide junctions. We touch upon the similarities between the underlying mathematical structure of the MIM waveguide and the PT symmetric quantum mechanical pseudo-Hermitian Hamiltonians. The rich set of modes that the MIM waveguide supports forms a canonical example against which other more complicated geometries can be compared. Our work here encompasses the microwave results, but extends also to waveguides with real metals even at infrared and optical frequencies.Comment: 17 pages, 13 figures, 2 tables, references expanded, typos fixed, figures slightly modifie