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The life preservers aboard airplanes play a critical role in ensuring occupant safety in water-related accidents. However, several airlines off-load life preservers to save fuel and costs. In this study, a cost–benefit analysis was performed considering the Life Quality Index to examine the necessity of life preservers aboard aircraft. It was noted that the placement of life preservers aboard airplanes was reasonable and beneficial in the recent 15 years. Although life preservers are primarily required for extended overwater (EOW) operations, the distance from the shoreline for most of the water-related accidents was considerably smaller than that of an EOW operation, and most water-related accidents occurred close to an airport. In other words, air passengers were at risk of water-related accidents, regardless of whether the flight was classified as an EOW flight. Thus, life preservers must be made available for all the occupants on all passenger flights, regardless of the flight path.

The rice glutelin fibrils (RGFs) were formed under heating at acidic condition, and the optimal condition was achieved at pH 2, 150 mM (ionic strength), 4% (protein concentration), 90 °C and 300 rpm (stirring speed) through the thioflavin T intensity. The atomic force microscopy images showed that the average contour length of RGFs increased from 100 to 365 nm under the optimal fibrillation. The average particle size of rice glutelin (RG) decreased from 650 to 221 nm after initial heating time. Combining the degraded subunits, it suggested that RG was hydrolyzed to peptides, then these released peptides assembled into the ordered fibrils via intermolecular interactions, accompanying by the structural rearrangement. Additionally, the foaming and emulsifying properties were improved during fibrillation, which could be related to the interfacial properties and structure of RGFs. This work will deepen the understanding of the formation of RGFs and explore their potential application.

Binomial detectability models are often used to estimate the size or abundance of a finite population in biology, epidemiology, demography and reliability. Special cases include incompletely observed multinomial models, capture–recapture models, and distance sampling models. The most commonly-used confidence interval for the abundance is the Wald-type confidence interval, which is based on the asymptotic normality of a reasonable point estimator of the abundance. However, the Wald-type confidence interval may have poor coverage accuracy and its lower limit may be less than the number of observations. In this paper, we rigorously establish that the likelihood ratio test statistic for the abundance under the binomial detectability models follows the chisquare limiting distribution with one degree of freedom. This provides a solid theoretical justification for the use of the proposed likelihood ratio confidence interval. Our simulations indicate that in comparison to the Wald-type confidence interval, the likelihood ratio confidence interval not only has more accurate coverage rate, but also exhibits more stable performance in a variety of binomial detectability models. The proposed interval is further illustrated through analyzing three real data-sets.

The assembly behavior of three selected legume proteins was monitored using thioflavin T (ThT) fluorescence intensity, atomic force microscopy (AFM) and dynamic light scattering (DLS) in this test. It was found that the cowpea protein (CoP) had the highest ability to form amyloid fibrils due to the higher ThT fluorescence intensity of CoP fibrils than chickpea protein (ChP) fibrils and lentil protein (LP) fibrils. These legume proteins were partially denatured during initial heating period, and then the elongation of fibrils was occurred with prolonged heating time. Correspondingly, the particle size of legume proteins decreased firstly, probably resulting from the degraded polypeptides and disrupted structure under the heat treatment and acid hydrolysis. Then the particle size of proteins increased with increasing heating time due to the reorganization of ordered structure. From the results of SDS-PAGE and AFM, vicilin fractions were more beneficial to the formation of fibrils, and the longer and flexible fibrils were observed in the vicilin enriched CoP fibrils, whereas the semiflexible fibrils and rigid fibrils were occurred in LP and ChP fibrils, respectively. In addition, the rheological properties of CoP fibrils were superior to ChP and LP fibrils, owing to the tight entanglement of the longer and flexible CoP fibrils. This work will strengthen the understanding of the formation mechanism of different legume proteins based fibrils and explore their potential application.

Drilling causes variation of the rock properties in the vicinity of a wellbore. In this article, we use the radial cylindrical layered model to examine monopole logging response with a two-dimensional axisymmetric finite difference method. Three variables are set, that is, the transition zone thickness, the source frequency and source-receiver spacing, respectively. We also use the slowness-time correlation-method to evaluate sound speed variations under different conditions. At last, based on the ray theory, the variation characteristics of the arrival time of the first wave under different conditions are analyzed. We conclude that the radial detection characteristics of compression waves are greatly affected by spacing. By combining different signals with various spacings, it is possible to obtain the tomography of the compressional wave velocities near wellbore.

Fractional quantum mechanics in the non-relativistic case is described by the space-fractional Schrodinger equation containing the fractional Riesz operator, which is a non-local operator. The non-locality makes it difficult to solve the fractional Schrodinger equation in the local potentials. In this paper, we study the solution of the fractional Schrodinger equation of a free particle moving on a circle by use of the Levy path integrals approach. We present the Levy path integrals propagator of a particle on circle and then use it to get the wave functions and energy eigenvalues of the free particle case. In addition, the Laplace transform, energy-time transform, and momentum representation of the free particle kernel are also obtained. The results of this paper contain the ones in standard quantum mechanics as special cases. The problem of a particle on circle is a fundamental problem of path integrals with topological constraints in quantum systems, and the method of Levy path integrals can be generalized to study more complex local potentials.