Estimation and testing for semiparametric mixtures of partially linear models

<p>In this paper, we study the estimation and inference for a class of semiparametric mixtures of partially linear models. We prove that the proposed models are identifiable under mild conditions, and then give a PL–EM algorithm estimation procedure based on profile likelihood. The asymptotic properties for the resulting estimators and the ascent property of the PL–EM algorithm are investigated. Furthermore, we develop a test statistic for testing whether the non parametric component has a linear structure. Monte Carlo simulations and a real data application highlight the interest of the proposed procedures.</p

Inactivation of <i>Heterosigma akashiwo</i> in ballast water by circular orifice plate-generated hydrodynamic cavitation

<p>The discharge of alien ballast water is a well-known, major reason for marine species invasion. Here, circular orifice plate-generated hydrodynamic cavitation was used to inactivate <i>Heterosigma akashiwo</i> in ballast water. In comparison with single- and multihole orifice plates, the conical-hole orifice plate yielded the highest inactivation percentage, 51.12%, and consumed only 6.84% energy (based on a 50% inactivation percentage). Repeating treatment, either using double series-connection or circling inactivation, elevated the inactivation percentage, yet consumed much more energy. The results indicate that conical-hole-generated hydrodynamic cavitation shows great potential as a pre-inactivation method for ballast water treatment.</p

Kinetic parameters of OfHex3 for different substrates.

<p>Kinetic parameters of OfHex3 for different substrates.</p

Production of <i>N</i>‑Acetyl‑d‑glucosamine from Mycelial Waste by a Combination of Bacterial Chitinases and an Insect <i>N</i>‑Acetyl‑d‑glucosaminidase

<i>N</i>-Acetyl-d-glucosamine (GlcNAc) has great potential to be used as a food additive and medicine. The enzymatic degradation of chitin-containing biomass for producing GlcNAc is an eco-friendly approach but suffers from a high cost. The economical efficiency can be improved by both optimizing the member and ratio of the chitinolytic enzymes and using new inexpensive substrates. To address this, a novel combination of bacterial and insect chitinolytic enzymes was developed in this study to efficiently produce GlcNAc from the mycelia of Asperillus niger, a fermentation waste. This enzyme combination contained three bacterial chitinases (chitinase A from Serratia marcescens (<i>Sm</i>ChiA), <i>Sm</i>ChiB, <i>Sm</i>ChiC) and one insect <i>N</i>-acetyl-d-glucosaminidase from Ostrinia furnacalis (<i>Of</i>Hex1) in a ratio of 39.1% of <i>Sm</i>ChiA, 26.7% of <i>Sm</i>ChiB, 32.9% of <i>Sm</i>ChiC, and 1.3% of <i>Of</i>Hex1. A yield of 6.3 mM (1.4 mg/mL) GlcNAc with a purity of 95% can be obtained from 10 mg/mL mycelial powder in 24 h. The enzyme combination reported here exhibited 5.8-fold higher hydrolytic activity over the commercial chitinase preparation derived from Streptomyces griseus

Expression pattern of OfHex3 during development.

<p>(<b>A</b>) Gene expression level of <i>OfHEX3</i> during development of <i>Ostrinia furnacalis</i>. Gene expression level was detected from the whole body of <i>O. furnacalis.</i> Numbers indicate relative gene expression levels compared with the housekeeping gene <i>OfRpS3</i>. (<b>B</b>) Protein expression profile of OfHex3 during development of <i>O. furnacalis</i>. Total protein was extracted from the whole body of <i>O. furnacalis</i> and the protein level of OfHex3 was detected using Hex3 specific antibody. Tubulin was chosen as a loading control. 3L2–5L5: third-instar day-2 to fifth-instar day-5; PP: prepupa; P-1, P-2: pupa day-1 and day-2.</p

Characterization of recombinant OfHex3.

<p>(<b>A</b>) No substrate inhibition of OfHex3 using physiological substrate (GlcNAc)₂. (<b>B</b>) HPLC analysis of the enzymatic activities of OfHex3 for (GlcNAc)₂ (i, ii) and GlcNAcβ1,2Man (iii, iv). The reactions were stopped immediately (i, iii) or after 1 hour (ii, iv) of incubation. (<b>C</b>) OfHex3 was detected in molting fluid. Lane 1: molting fluid from <i>Ostrinia furnacalis</i>; Lane 2: molting fluid from <i>Bombyx mori</i>. (<b>D</b>) Pull-down assay with recombinant OfHex1-His protein. Lane 1: purified OfHex1-His incubated with PBS buffer as a negative control; Lane 2: purified OfHex1-His protein incubated with molting fluid from <i>B. mori</i>; Lane 3: another negative control that molting fluid from <i>B. mori</i> incubated with PBS to exclude the possibility of unspecific binding to the NTA beads; Lane 4: The input of molting fluid from <i>B. mori</i> for the pull-down assay. Hex3 was detected by western blot using Hex3 specific antibody.</p

Potential Application and Molecular Mechanisms of Soy Protein on the Enhancement of Graphite Nanoplatelet Dispersion

A stable dispersion of graphitic nanofillers in aqueous solution is an important prerequisite for the applications and development in graphitic nanofiller-based nanocomposites. Traditional treatments of the graphitic surfaces with different chemicals are time and energy consuming, and more seriously raise great environmental concerns. In this study, through combination of simulations and experiments we demonstrate that the soy protein, one of the most widely available proteins from the renewable resource, when properly denatured by trifluoroethanol (TFE) and heat, can be utilized to effectively treat the graphite nanoplatelet (GNP) surface and improve the dispersion. Through molecular simulations we find that the tertiary structures of soy protein are mostly destroyed under the action of TFE at high temperature. As a consequence, most aromatic residues which are originally hidden inside the hydrophobic cores become accessible and form π–π stacking interaction with the GNP surface, strengthening the adsorption of soy proteins onto the GNP surface. The adsorption of soy protein modifies the GNP surface energy, reduces the interaction force among GNPs and leads to better dispersion. Our simulation results agree with the experimental measurements on GNP dispersion. The work herein demonstrates the importance and the potential of the concept that a protein, when its structures are properly manipulated, can be exploited in nanotechnologies to improve performance and explore new functionalities

Exploring ortho‐(4,4′‐dimethoxybenzhydryl) substitution in iron ethylene polymerization catalysts: Co‐catalyst effects, thermal stability, and polymer molecular weight variations

Six different types of 4,4′-dimethoxybenzhydryl-substituted bis(arylimino)pyridine-iron(II) chloride complex—[2-{{2,6-((p-MeOPh) CH) -4-MeC H }N=CMe}-6-(ArN=CMe)C H N]FeCl (Ar = 2,6-Me C H (Fe1), 2,6-Et C H (Fe2), 2,6- Pr C H (Fe3), 2,4,6-Me C H (Fe4), 2,6-Et -4-MeC H (Fe5), 2,6-((p-MeOPh) CH) -4-MeC H (Fe6)—are reported. The molecular structures of Fe2 and Fe3 emphasize the unsymmetrical nature of the N,N,N-chelating ligand and the steric protection exerted by the ortho-(4,4′-dimethyoxybenzhydryl) groups. A range in catalytic activities for ethylene polymerization was observed when Fe1–Fe6 were treated with either methylaluminoxane (MAO) or modified methylaluminoxane (MMAO). In particular, Fe1/MAO bearing the least bulky N-2,6-dimethylphenyl group exhibited a very high activity of 1.11 × 10 g (PE) mol (Fe) h at 70°C/10 atm over a 30-min run time that remained high even after 60 min, an observation highlighting its appreciable catalyst lifetime and thermal stability. In addition, the polyethylene formed by this catalyst class displayed desirable characteristics such as high linearity and high molecular weight (M range: 5.17–7.62 × 10 g mol ). Indeed, the molecular weight of the polymer produced using Fe1 (with MAO or MMAO) exceeds that obtained using related benzhydryl-containing bis(imino)pyridine-iron catalysts. As a general feature, activation of Fe1–Fe6 with MMAO led to lower activity and lower molecular weight polyethylene, especially for runs performed at 1 atm ethylene pressure. 2 2 6 2 5 3 2 2 6 3 2 6 3 2 6 3 3 6 2 2 6 2 2 2 6 2 w i 7 −1 −1 5 −

The <i>in-vivo</i> patient experimental results (right arm without lymphedema, and left arm with lymphedema).

<p>(A1) and (A2) are right and left arm B-mode images of a 50-year-old breast cancer patient with moderate degree lymphedema, 1 year post-radiotherapy. (B1) and (B2) are right and left axial displacement images. (C1) and (C2) are right and left lateral displacement images. (D1) and (D2) are right and left axial strain images. (E1) and (E2) are right and left lateral strain images.</p

Microbial Secondary Metabolite, Phlegmacin B₁, as a Novel Inhibitor of Insect Chitinolytic Enzymes

Periodic chitin remodeling during insect growth and development requires a synergistic action of two glycosyl hydrolase (GH) family enzymes, GH18 chitinase and GH20 β-N-acetylhexosaminidase (Hex). Inhibiting either or both of these enzymes is a promising strategy for pest control and management. In this study, <i>Of</i>Chi-h (a GH18 chitinase) and <i>Of</i>Hex1 (a GH20 Hex) from <i>Ostrinia furnacalis</i> were used to screen a library of microbial secondary metabolites. Phlegmacin B₁ was found to be the inhibitor of both <i>Of</i>Chi-h and <i>Of</i>Hex1 with <i>K</i>_i values of 5.5 μM and 26 μM, respectively. Injection and feeding experiments demonstrated that phlegmacin B₁ has insecticidal effect on <i>O. furnacalis</i>’s larvae. Phlegmacin B₁ was predicted to bind to the active pockets of both <i>Of</i>Chi-h and <i>Of</i>Hex1. Phlegmacin B₁ also showed moderate inhibitory activities against other bacterial and insect GH18 enzymes. This work provides an example of exploiting microbial secondary metabolites as potential pest control and management agents