Novel bombesin-like peptide binding proteins from lung

Our first year of experience in the use of PET scanning in the management of nine patients with ovarian cancer leads us to conclude that this promising new technique may be more sensitive than either serum CA-125 determinations or computed tomography for the detection and demonstration of residual or recurrent abdominal and pelvic tumor. Seven of these patients underwent second-look laparotomy which confirmed our impressions from preoperative PET scans in six patients, and the one other scan showed a focus of metabolic uptake coinciding with residual tumor in our retrospective review. The clinical courses of two other patients who did not undergo laparotomy confirmed the impressions gained from PET scans.     

Effect of Y2O3 dispersoids in 80Ni-20Cr alloy on the early stages of oxidation at low-oxygen potential

Specimens of a 80Ni-20Cr type alloy, with and without Y₂O₃ dispersoid particles, were oxidized at 1000°C in H₂/H₂O mixtures where the partial pressure of oxygen (P _{O 2}) was varied between 10₃ and 10₂₄ atm. Oxide particles nucleated homogeneously on both alloys, and preferential nucleation on dispersoid particles at the surface was not observed. Continuous Cr₂O₃ films formed slightly faster at aP _{O 2} of 10^–21 atm on the alloy containing the dispersoid, but the difference was negligible at higher pressures. Oxidation atP _{O 2}=10^-19 and 10^–21 atm involved both the formation of Cr₂O₃ and the evaporation of chromium. Thin films of -Al₂O₃ were observed on both alloys after oxidation atP _{O 2}.     

An Efficient Bifunctional Air Electrode for Reversible Protonic Ceramic Electrochemical Cells

One of the main bottlenecks that limit the performance of reversible protonic ceramic electrochemical cells (R-PCECs) is the sluggish kinetics of the oxygen reduction and evolution reactions (ORR and OER). Here, the significantly enhanced ORR and OER kinetics and stability of a conventional La_0.6Sr_0.4Co_0.2Fe_0.8O_3–δ (LSCF) air electrode by an efficient catalyst coating of barium cobaltite (BCO) is reported. The polarization resistance of a BCO-coated LSCF air electrode at 600 ° C is 0.16  Ω  cm², about 30% of that of the bare LSCF air electrode under the same conditions. Further, an R-PCEC with the BCO-coated LSCF air electrode shows exceptional performance in both fuel cell (peak power density of 1.16 W cm⁻² at 600 ° C) and electrolysis (current density of 1.80 A cm⁻² at 600 ° C at 1.3 V) modes. The performance enhancement is attributed mainly to the facilitated rate of oxygen surface exchange.     

Generalized radial‐return mapping algorithm for anisotropic von Mises plasticity framed in material eigenspace

A computationally efficient integration algorithm for anisotropic plasticity is proposed, which is identified as a generalization of the radial‐return mapping algorithm to anisotropy. The algorithm is based upon formulation within the eigenspace of a material anisotropy tensor associated with anisotropic quadratic von Mises (J₂) plasticity (also called Hill plasticity), for which it is shown to ensure that the flow rule remains associative, ie, the normality condition is satisfied. Extension of the algorithm to include anisotropic elasticity (anisotropic elastoplasticity) is further provided, made possible by the identification of a certain fourth‐order material tensor dependent on both the elastic and plastic anisotropy. The derivation of the fully elastoplastically anisotropic algorithm involves further complexity, but the resulting algorithm is shown to closely resemble the purely plastically anisotropic one once the appropriate eigenspace is identified. The proposed generalized radial‐return algorithm is compared to a classical closest‐point projection algorithm, for which it is shown to provide considerable advantage in computational cost. The efficiency, accuracy, and robustness of the algorithm are demonstrated through various illustrative test cases and in the finite element simulation of Taylor impact tests on tantalum.     

Jerry can carriage is an effective predictor of stretcher carry performance

Carrying a casualty on a stretcher is a critical task conducted in a range of occupations. To ensure that personnel have the requisite physical capacity to conduct this task, two bilateral jerry can carries were used to predict individual performance in a four-person stretcher carry. Results demonstrated a bilateral 22-kg jerry can carry (R² = 0.59) had superior predictive ability of stretcher carry performance than a bilateral 15-kg jerry can carry (R² = 0.46). Pre- to post-carry changes in grip endurance (p > 0.05), back–leg isometric strength (p > 0.05) and leg power (p > 0.05) were not significantly different between carry tasks. There was no significant difference in heart rate (p > 0.05) and oxygen consumption (p > 0.05) between the stretcher carry and either jerry can carry. Thus, on the basis of performance correlations and physiological measures, the 22-kg jerry can carry is an appropriate predictive assessment of four-person stretcher carriage.

Practitioner Summary: This study investigated the ability of a jerry can carry to predict individual performance on a four-person stretcher carry. Performance correlations were substantiated with physiological measures to demonstrate similar physical requirements between task and test. These results can be used to set physical employment standards to assess stretcher carriage.     

Structure development in processing of polypropylene films with additives

The crystallization behavior, modification of crystalline form, and orientation in polypropylene processed by blow film extrusion was studied as a function of processing parameters as well as different types of additives. The isothermal crystallization rate was greatly enhanced in the presence of certain additives, especially CaCO₃. The crystalline form was predominantly α type in both compression molded or blow extruded films. However, there was an unusually large intensity of the α₀₄₀ peak in the X-ray diffraction of the latter case films. The variation of the peak intensities and the increase of birefringence with increase of take-up speed has been explained on the basis of orientation induced by uniaxial stress in the machine direction. This orientation contained two components, namely the orientation of the b axis of the crystallites and the orientation of loosely bound polymer chains in the amorphous regions. © 1995 John Wiley & Sons, Inc.     

Studies on castor oil. II. Hydrogenation of castor oil

1. Products of low iodine value (<10.0) and hydroxyl value (35–40) can be readily obtained by hydrogenating castor oil at atmospheric pressure and at temperatures of the order of 220°, using 1.0% Raney nickel.
2. Dehydration of ricinoleic acid and subsequent hydrogenation of the resulting double bond as also simple saturation of ricinoleic acid are the main reactions occurring during the hydrogenation of castor oil under ordinary conditions.
3. Increase in the amount of catalyst favors more the hydrogenation of double bond at lower temperatures and both dehydration and hydrogenation at about 220°, which seems to be the optimum temperature for the maximum conversion of ricinoleic acid into nonhydroxy acids with both Raney and dryreduced nickel at atmospheric pressures.
4. Higher proportions of catalyst, addition of catalyst stepwise, and higher temperature of hydrogenation cause considerable splitting and estolide formation.
5. When hydrogenation is carried out at room temperature, under a pressure of 40 p.s.i. with alcohol as solvent, a product rich in monohydroxy stearic acid is obtained.
6. True unsaturation of hydrogenated castor oil is measured by the Wijs method at 15–20°C.

     

Numerical investigation of thermal performance of heat loss of parabolic trough receiver

Based on the analysis of computation methods and heat transfer processes of the parabolic trough receiver running in steady state, a two-dimensional empirical model was developed to investigate the thermal performance of heat loss of parabolic trough receivers under steady state equilibrium. A numerical simulation was conducted for the parabolic trough receiver involved in a literature. Comparisons between numerical and experimental results show that the empirical model is accurate enough and can be used to...     

The correct exponent for the Gotsman–Linial Conjecture

We prove new bounds on the average sensitivity of polynomial threshold functions. In particular, we show that for f, a degree-d polynomial threshold function in n variables that $$\mathbb{AS}(f) \leq \sqrt{n}(\log(n))^{O(d log(d))}2^{O(d^2 log(d))}.$$ This bound amounts to a significant improvement over previous bounds, and in particular, for fixed d gives the same asymptotic exponent of n as the one predicted by the Gotsman–Linial Conjecture.