Energy Landscape and Global Optimization for a Frustrated Model Protein

The three-color (BLN) 69-residue model protein was designed to exhibit frustrated folding. We investigate the energy landscape of this protein using disconnectivity graphs and compare it to a Go model, which is designed to reduce the frustration by removing all non-native attractive interactions. Finding the global minimum on a frustrated energy landscape is a good test of global optimization techniques, and we present calculations evaluating the performance of basin-hopping and genetic algorithms for this system.Comparisons are made with the widely studied 46-residue BLN protein.We show that the energy landscape of the 69-residue BLN protein contains several deep funnels, each of which corresponds to a different β-barrel structure

Spectral splitting photovoltaics using perovskite and wideband dye-sensitized solar cells

The extension of the light absorption of photovoltaics into the near-infrared region is important to increase the energy conversion efficiency. Although the progress of the lead halide perovskite solar cells is remarkable, and high conversion efficiency of >20% has been reached, their absorption limit on the long-wavelength side is similar to 800 nm. To further enhance the conversion efficiency of perovskite-based photovoltaics, a hybridized system with near-infrared photovoltaics is a useful approach. Here we report a panchromatic sensitizer, coded DX3, that exhibits a broad response into the near-infrared, up to similar to 1100 nm, and a photocurrent density exceeding 30 mA cm(-2) in simulated air mass 1.5 standard solar radiation. Using the DX3-based dye-sensitized solar cell in conjunction with a perovskite cell that harvests visible light, the hybridized mesoscopic photovoltaics achieved a conversion efficiency of 21.5% using a system of spectral splitting.open0

Evaluation of commercial soy sauce koji strains of Aspergillus oryzae for γ-aminobutyric acid (GABA) production

In this study, four selected commercial strains of Aspergillus oryzae were collected from soy sauce koji. These A. oryzae strains designated as NSK, NSZ, NSJ and NST shared similar morphological characteristics with the reference strain (A. oryzae FRR 1675) which confirmed them as A. oryzae species. They were further evaluated for their ability to produce γ-aminobutyric acid (GABA) by cultivating the spore suspension in a broth medium containing 0.4 % (w/v) of glutamic acid as a substrate for GABA production. The results showed that these strains were capable of producing GABA; however, the concentrations differed significantly (P < 0.05) among themselves. Based on the A. oryzae strains, highest GABA concentration was obtained from NSK (194 mg/L) followed by NSZ (63 mg/L), NSJ (51.53 mg/L) and NST (31.66 mg/L). Therefore, A. oryzae NSK was characterized and the sequence was found to be similar to A. oryzae and A. flavus with 99 % similarity. The evolutionary distance (K nuc) between sequences of identical fungal species was calculated and a phylogenetic tree prepared from the K nuc data showed that the isolate belonged to the A. oryzae species. This finding may allow the development of GABA-rich ingredients using A. oryzae NSK as a starter culture for soy sauce production

A nonlinear magnetorheological elastomer model based on fractional viscoelasticity, magnetic dipole interactions, and adaptive smooth Coulomb friction

© 2019 Elsevier Ltd Magnetorheological elastomers (MRE) are emerging as smart materials for application in the field of the intelligent devices and structures. In order to design MRE-based vibration control devices, their dynamic behavior should be mathematically represented with respect to broadband excitation frequency, amplitude, and the applied magnetic field. In this study, a nonlinear MRE model consisting of three parts – a fractional viscoelasticity model, magnetic dipole model, and an adaptive smooth Coulomb friction model – is developed. The fractional Maxwell model with only three parameters was introduced to simulate the dynamic behavior of MRE in a wide frequency range. A magnetic interaction model for adjacent particles was investigated and the magnetic force corresponding to the particle volume was calculated. We found that the interaction force not only affects the shear modulus, but also affects slipping at the interface between the particle and matrix. The adaptive smooth Coulomb friction used to model the magnetic field-dependent properties of the MRE accurately described the behavior of the material over a wide range of amplitudes at different magnetic field strengths. The model parameters were estimated by a simple procedure and the proposed model was found to represent MRE characteristics accurately. Therefore, the new model is expected to be advantageous for designing MRE-based vibration devices

Effect of intake of virgin coconut oil (<em>Cocos nucifera</em> L.) on the spleen and small intestinal immune cells and liver lipid of mice

Virgin coconut oil (Cocos nucifera L.) (VCO) is consumed worldwide and is rich in medium-chain fatty acids (MCFAs) and lauric acid (LA). The aim of this study was to examine the immuno-stimulation effect of VCO produced in Sri Lanka. Three groups of mice were fed either a lard diet (L), a fish-oil diet (F) or a coconut oil diet (C) for 6 weeks. During the experimental period, no significant differences in total food intakes or body weights of mice were observed among the three groups. Perirenal fat tissue weight, plasma Triacylglycerol (TG) level and total liver lipids were lower in the F group mice than those in the L and C group mice. The total cholesterol levels in livers of mice in the C group showed higher than that of the other groups. The cytokine IL-12 levels in spleen cells were highest in the C group mice, followed in order by the mice in F and L groups. Our studies clearly show that the plasma IgA and the cytokine IL-12 levels in the spleen and PP cells of mice increased in spite of the accumulation of liver lipids in mice by the intake of VCO produced in Sri Lanka

Hemodynamic responses among three tracheal intubation devices in normotensive and hypertensive patients

We compare hemodynamic responses in normotensive and hypertensive anesthetized paralyzed patients among three intubation devices: the Macintosh laryngoscope (LS), the Trachlight™ lightwand (LW), and the intubating laryngeal mask airway Fastrach™ (ILM). Seventy-five normotensive and 75 hypertensive patients were randomly assigned to each intubation device (n = 25). Noninvasive systolic blood pressure (SBP) and diastolic blood pressure (DBP) and heart rate (HR) were recorded immediately preinduction, immediately preintubation, and every minute for the first 5 min after the successful intubation. The number of intubation attempts, the time to successful intubation, and any airway injuries were recorded. Pharyngolaryngeal morbidity was assessed 18-24 h after surgery by a blinded investigator. In all groups, there was a reduction in SBP and DBP but no change in HR immediately preintubation compared with baseline values. In all groups, HR increased, but there were no increases in SBP and DBP other than in DBP in the LS/hypertensive group after intubation compared with baseline values. In normotensive patients, there were no differences in any hemodynamic variables among the three devices. In hypertensive patients, SBP and DBP in the LS group were significantly higher than the ILM and LW groups for 2 min after intubation, but there were no differences in HR among the devices. The number of intubation attempts was similar among groups, but intubation time was longer for the ILM group. The incidence of airway injury was more frequent for the ILM than the LS and LW groups (16% versus 0% versus 0%). There were no differences in pharyngolaryngeal morbidity among groups. We conclude that both the ILM and the LW attenuated the hemodynamic stress response to tracheal intubation compared with the LS in hypertensive, but not in normotensive, anesthetized paralyzed patients