Water vapor sorption in starch granules

A mathematical model proposed for diffusion in spherical particles can be solved on a digital computer. The model includes particle size distribution and variable diffusion coefficient of the form D = Doe^αC, where D is the diffusion coefficient, D₀ and α are constants, and C is the moisture content. Isothermal experimental measurements were made gravimetrically on a Cahn electrobalance by vacuum sorption techniques. The model adequately predicts the absorption characteristics of water vapor in starch granules. Although swelling is neglected in the model, it does contribute to sorption characteristics.     

Expression of the neuroprotective slow Wallerian degeneration (Wld S ) gene in non-neuronal tissues

Background  

The slow Wallerian Degeneration (Wld ^S ) gene specifically protects axonal and synaptic compartments of neurons from a wide variety of degeneration-inducing stimuli, including; traumatic injury, Parkinson's disease, demyelinating neuropathies, some forms of motor neuron disease and global cerebral ischemia. The Wld ^S gene encodes a novel Ube4b-Nmnat1 chimeric protein (Wld^S protein) that is responsible for conferring the neuroprotective phenotype. How the chimeric Wld^S protein confers neuroprotection remains controversial, but several studies have shown that expression in neurons in vivo and in vitro modifies key cellular pathways, including; NAD biosynthesis, ubiquitination, the mitochondrial proteome, cell cycle status and cell stress. Whether similar changes are induced in non-neuronal tissue and organs at a basal level in vivo remains to be determined. This may be of particular importance for the development and application of neuroprotective therapeutic strategies based around Wld ^S -mediated pathways designed for use in human patients.     

Lensless intracavity focusing in a passively Q-switched all-fiber laser using the mode-field-area mismatch

Intense lensless intracavity focusing in a saturable absorber Q-switched all-fiber laser resonator by use of loss arrangement and mode-field-area mismatch between the fibers is investigated for the first time. The intracavity power distribution was related to the locations and values of the cavity losses as the saturable absorption loss, the reflection loss of the output coupler, and the splicing loss between the gain fiber and the absorber fiber. With a mode-field-area mismatch and a reduced splicing loss with the gain fiber, a power density in the absorber fiber was achieved that was 11.9 times higher than that in the gain fiber.     

The interval-valued fuzzy TOPSIS method and experimental analysis

The purpose of this paper is to extend the TOPSIS method based on interval-valued fuzzy sets in decision analysis. Hwang and Yoon developed the technique for order preference by similarity to ideal solution (TOPSIS) in 1981. TOPSIS has been widely used to rank the preference order of alternatives and determine the optimal choice. Considering the fact that it is difficult to precisely attach the numerical measures to the relative importance of the attributes and to the impacts of the alternatives on these attributes in some cases, therefore, the TOPSIS method has been extended for interval-valued fuzzy data in this paper. In addition, a comprehensive experimental analysis to observe the interval-valued fuzzy TOPSIS results yielded by different distance measures is presented. A comparative analysis of interval-valued fuzzy TOPSIS rankings from each distance measure is illustrated with discussions on consistency rates, contradiction rates, and average Spearman correlation coefficients. Finally, a second-order regression model is provided to highlight the effects of the number of alternatives, the number of attributes, and distance measures on average Spearmen correlation coefficients.     

Synthesis and Cyclization of Sulfur-Substituted Azido Dienes to Pyrrolizidine and Indolizidine Moieties

Sulfur-substituted azido dienes 1 and 11 , conveniently prepared from the corresponding 3-sulfolenes 5 and 10 , were thermolyzed to give pyrrolizidine and indolizidine products, 6 , 7 and 14 .     

Effective charges of polyelectrolytes in a salt-free solution based on counterion chemical potential

The phenomenon of counterion condensation around a flexible polyelectrolyte chain with N monomers is investigated by Monte Carlo simulations in terms of the degree of ionization alpha, which is proportional to the effective charge. It is operationally defined as the ratio of observed to intrinsic counterion concentration, alpha = co/ci. The observed counterion concentration in the dilute polyelectrolyte solution is equivalent to an electrolyte solution of concentration co with the same counterion chemical potential. It can be determined directly by thermodynamic experiments such as ion-selective electrode. With the polyelectrolyte fixed at the center of the spherical Wigner-Seitz cell, the polymer conformation, counterion distribution, and chemical potential can be obtained. Our simulation shows that the degree of ionization rises as the polymer concentration decreases. This behavior is opposite to that calculated from the infinitely long charged rod model, which is often used to study counterion condensation. Moreover, we find that, for a specified line charge density, alpha decreases with an increment in chain length and chain flexibility. In fact, the degree of ionization is found to decline with increasing polymer fractal dimension, which can be tuned by varying bending modulus and solvent quality. Those results can be qualitatively explained by a simple model of two-phase approximation.     

Regularizations and superconformal anomalies

By using different regularization methods we demonstrate that supersymmetry invariance is maintained up to one-loop order in supersymmetric gauge theories and calculate the superconformal anomalies.     

Conformal anomalies in a general background metric

By using the dimensional regularization procedure, we explicitly calculate the coefficients of conformal anomalies in a general background metric due to scalar, spin $\text{1}\text{2}$ fermion, gauge and gravitation fields.     

Improved Computer Program for Magnetron Injection Gun Design

Gyrotron has received extensive attention owing to its high-power capability, especially when the wavelength shrinks below the millimeter-wave range. The electron beam of a gyrotron is typically generated by a magnetron injection gun (MIG). For high cathode current density, the MIG may operate in a region that combines temperature limited and space-charge limited emissions. An improved computer program for electron gun design is appropriate for MIGs that operate between space-charge limited and temperature limited emission. Moreover, the initial input formation of the program resembles that of the EGUN code. Analysis of a Pierce electron gun and MIGs reveals that the stimulated beam current appears consistent with the measured results. However, EGUN simulation results in which the cathode emitters of MIGs are chosen for the temperature limited emission differ from those of our simulation results. This difference is most likely owing to that the initial emitting energy can not be completely described in the EGUN simulation. Finally, the improved computer program is used to design a MIG for a Ka-band, TE₀₁ mode gyro-TWT.