Analysis of molecular forms of albumin in urine

Albumin is not only one of the most abundant urinary protein components and one of the most widely used clinical markers for kidney disease, it also is a significant source of molecular complexity of the urinary proteome and peptidome. Urine contains multiple fragments and modified forms of albumin. Analysis of molecular forms of albumin in urine is of fundamental importance for understanding clinical assays for albumin quantification, specimen stability, and proteomic and peptidomic analysis of urine.     

High density polyethylene foams. III. Tensile properties

The room temperature tensile properties of closed‐cell polyethylene foams have been investigated. High density polyethylene (HDPE) foams of four different molecular weight were used to study the effect of molecular weight and foam density on mechanical properties during tension and at the break point. It was found that increasing the molecular weight changes the tensile behavior of polyethylene foams from brittle to ductile fractures. For brittle foams, the break strength follows a square power‐law model and the break strain is independent of the volume fraction of the voids. For ductile foams, the normalized yield strength also follows a square power‐law relation with normalized density, the yield strain is similar to the value of the solid polymer and remains constant for all void volume fractions, and the break strain increases with HDPE molecular weight. Finally, the toughness of the foams was found to increase with normalized density and HDPE molecular weight. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2130–2138, 2003     

Kinetics of the reaction between carbon dioxide and hydrogen over a ruthenium catalyst in a continuous stirred tank reactor

The catalytic reaction between carbon dioxide and hydrogen over a surface coated ruthenium catalyst was investigated in a stirred tank reactor, under isothermal conditions from 200 to 300°C. The kinetic data obtained were analysed by the Hougen-Watson method. Non-linear least squares analysis was used to discriminate among 28 rate models. The following Hougen-Watson type rate equation was selected.     

Review of real-time vehicle schedule recovery methods in transportation services

This paper presents a comprehensive review on methods for real-time schedule recovery in transportation services. The survey concentrates on published research on recovery of planned schedules in the occurrence of one or several severe disruptions such as vehicle breakdowns, accidents, and delays. Only vehicle assignment and rescheduling are reviewed; crew scheduling and passenger logistics problems during disruptions are not. Real-time vehicle schedule recovery problems (RTVSRP) are classified into three classes: vehicle rescheduling, for road-based services, train-based rescheduling, and airline schedule recovery problems. For each class, a classification of the models is presented based on problem formulations and solution strategies. The paper concludes that RTVSRP is a challenging problem that requires quick and good quality solutions to very difficult and complex situations, involving several different contexts, restrictions, and objectives. The paper also identifies research gaps to be investigated in the future, stimulating research in this area.     

A single amino acid substitution can restore the solubility of aggregated colicin A mutants in Escherichia coli

Mutants of colicin A have been prepared in which the three tryptophanresidues (Trp86, Trpl30 and Trpl40), localized in the C-terminaldomain of the soluble wild-type protein, have been substitutedby phenylalanine. The Trpl40Phe single mutation had the effectof decreasing the percentage of protein that is expressed asinsoluble aggregates. The created hydrophobic cavity decreasedthe stability of the protein during its folding, resulting inpartial aggregation in the cytoplasm of the Escherichia coli-producingcells. Aggregation was increased when Trpl40 was substitutedby Lys, Leu or Cys, or if the Trpl40 mutation was combined withthe Trp86Phe and/ or Trpl30Phe mutations. A single mutation,Lysll3Phe, however, was able to restore the solubility of theaggregated mutants in vivo. Detailed analysis of the 3-D structureof the C-terminal domain of colicin A suggests that fillingof the hydrophobic cavity is responsible for this effect.     

Preparation and characterization of multilayer foamed composite by rotational molding

A multilayer material was produced by rotational molding to study the effect of composition on the mechanical behavior of a cylindrical liquid container. The first (outer) layer was a composite of linear medium density polyethylene (LMDPE) with 5, 10, or 15 wt% agave fiber (AF). The core (middle) layer was foamed LMDPE with different amount of foaming agent (0, 0.15, 0.25, 0.5, and 0.75 wt%). Finally, the third (internal) layer was neat LMDPE. This structure was produced to optimize the mechanical properties of the molded parts while decreasing weight with good surface properties. From the morphological analysis, it was observed that the layers are not always well defined because of gas migration, especially from the foamed core to the composite layer. As expected, density increased with fiber content while decreasing with foaming agent concentration. In general, impact strength (Charpy and Gardner) was directly related to the overall density of the part. POLYM. ENG. SCI., 56:278–286, 2016. © 2015 Society of Plastics Engineers     

Diversity‐Oriented Synthesis of Diol‐Based Peptidomimetics as Potential HIV Protease Inhibitors and Antitumor Agents

Peptidomimetic HIV protease inhibitors are an important class of drugs used in the treatment of AIDS. The synthesis of a new type of diol‐based peptidomimetics is described. Our route is flexible, uses d ‐glucal as an inexpensive starting material, and makes minimal use of protection/deprotection cycles. Binding affinities from molecular docking simulations suggest that these compounds are potential inhibitors of HIV protease. Moreover, the antiproliferative activities of compounds 33 a , 35 a , and 35 b on HT‐29, M21, and MCF7 cancer cell lines are in the low micromolar range. The results provide a platform that could facilitate the development of medically relevant asymmetrical diol‐based peptidomimetics.     

Zirconium carbide oxidation: Kinetics and oxygen diffusion through the intermediate layer

Oxidation of hot‐pressed ZrC was investigated in air in the 1073‐1373 K range. The kinetics were linear at 1073 K, whereas at higher temperature samples initially followed linear kinetics before undergoing rapid oxidation leading to a Maltese cross shape of the oxide. The linear kinetics at 1073 K was governed by inward oxygen diffusion through an intermediate layer of constant thickness between ZrC and ZrO₂ which was comprised of amorphous carbon and ZrO₂ nanocrystals. Diffusion of oxygen through the intermediate layer was measured to be 9 × 10^?10 cm² s^?1 using ¹⁸O as a tracer in a double oxidation experiment in ¹⁶O/¹⁸O. Oxidation at 1073 and 1173 K produced samples made of m‐ZrO₂ and either t‐ or c‐ZrO₂ with an adherent intermediate layer made of amorphous carbon and ZrO₂, whereas oxidation at 1273 and 1373 K produced samples with a voluminous oxide made of m‐ZrO₂ showing a gap between ZrC and the oxide. A substoichiometric zirconia layer was found at the gap at 1273 K and no carbon uptake was detected in this layer when compared with the top oxide layer. The loss of the intermediate layer and the slowdown of the linear rate constant (g m^?2 s^?1) at 1273 K compared to 1173 K was correlated with the preferential oxidation of carbon at the intermediate layer which would leave as CO and/or CO₂ leaving a gap between ZrC and substoichiometric zirconia.