Keywords: aging; atrophy; comparative anatomy; corpus callosum; Pan troglodytes The human corpus callosum exhibits substantial atrophy in old age, which is stronger than what would be predicted from ...parallel changes in overall brain anatomy. To date, however, it has not been conclusively established whether this accentuated decline represents a common feature of brain aging across species, or whether it is a specific characteristic of the aging human brain. In the present cross-sectional study, we address this question by comparing age-related difference in corpus callosum morphology of chimpanzees and humans. For this purpose, we measured total midsagittal area and regional thickness of the corpus callosum from T1-weighted MRI data from 213 chimpanzees, aged between 9 and 54years. The results were compared with data drawn from a large-scale human sample which was age-range matched using two strategies: (a) matching by chronological age (human sample size: n = 562), or (b) matching by accounting for differences in longevity and various maturational events between the species (i.e., adjusted human age range: 13.6 to 80.9years; n = 664). Using generalized additive modeling to fit and compare aging trajectories, we found significant differences between the two species. The chimpanzee aging trajectory compared with the human trajectory was characterized by a slower increase from adolescence to middle adulthood, and by a lack of substantial decline from middle to old adulthood, which, however, was present in humans. Thus, the accentuated decline of the corpus callosum found in aging humans is not a universal characteristic of the aging brain, and appears to be human-specific. Article Note: Funding information National Institutes of Health, Grant/Award Numbers: HD-60563, NS-092988, NS-42867, NS-73134; Norges Forskningsrad, Grant/Award Number: Toppforsk 249931; University of Tartu Byline: Rene Westerhausen, Anders M. Fjell, Kristiina Kompus, Steven J. Schapiro, Chet C. Sherwood, Kristine B. Walhovd, William D. Hopkins
The self-condensation of cyclopentanone has been studied over calcined and uncalcined TiO.sub.2-ZrO.sub.2. The catalyst properties were examined by XRD, FTIR, SEM, N.sub.2 adsorption-desorption, and ...pyridine FTIR. Compared with calcined TiO.sub.2-ZrO.sub.2, uncalcined TiO.sub.2-ZrO.sub.2 exhibited superior catalytic performance (94% conversion of cyclopentanone and 86% yield of dimer). This might be because uncalcined TiO.sub.2-ZrO.sub.2 has both Lewis and Brønsted acids, while calcined TiO.sub.2-ZrO.sub.2 only contains Lewis acids. Kinetics analysis indicated that C-C coupling was the rate-limiting step on the two catalysts. For uncalcined TiO.sub.2-ZrO.sub.2, the C-C coupling occurred between the two species on the catalyst surface. Through the H bond, the cyclopentanone was firmly adsorbed on the catalyst surface by Brønsted acid sites, then the enol intermediate could attack another cyclopentanone polarized by adjacent Lewis acid sites. As a consequence, the coexistence of Brønsted and Lewis acids in catalysts exhibited enhanced activity in cyclopentanone self-condensation.
The static melting method is used to prepare KNO.sub.3-NaNO.sub.3-NaCl ternary mixed molten salt containing 5-20 mass% NaCl, and the thermal physical parameters such as specific heat capacity, ...melting point, and latent heat of phase change are measured by differential scanning calorimetry. The microstructures of the mixed molten salts are characterized by XRD and SEM. The experimental results show that compared with the base salt, after adding different mass fractions of NaCl, the melting point of the molten salts was reduced by about 24.8%, and the latent heat of phase change was increased by 22.71-52.53 J g.sup.-1, the solid and liquid state specific heat capacity of molten salts increased by 3.4% and 2.3% after the addition of 10 mass% NaCl. The addition of 15 mass% NaCl formed a special chlorine salt layer on the surface of the molten salt. This structure reduced the intermolecular voids and enhanced the intermolecular force, which may be the reason for the increase in specific heat capacity and latent heat of phase change.
As a new breed of grouper hybrid breeding, EFT has the advantages of delicious flesh, fast growth, and high deformity rate. We explored the metamorphosis and skeletal development of Epinephelus ...fuscoguttatus and hybrids (EFT) of E. fuscoguttatus (♀) and E. tukula (♂). EFT grew slightly slower than E. fuscoguttatus during the larval period but grew faster during the juvenile period. The sequences of skeletal development were similar in EFT and E. fuscoguttatus. Newly hatched larvae did not have skeletons until 5days after hatching (DAH) when head cartilage started to develop and complete at 43days later. The vertebral column started to develop at 11DAH and was completed at 38DAH. Pectoral fin development began at 5DAH and ossification was completed at 48DAH in EFT and at 43DAH in E. fuscoguttatus. Anal fin development started at 11DAH and ossification was completed earlier in EFT than in E. fuscoguttatus. The caudal fins of the two groupers developed at 8DAH and ossified earlier in EFT than in E. fuscoguttatus. In contrast, E. fuscoguttatus had one additional epural than EFT. These results provide important basic biological data for the growth and skeletal development of pure and hybrid grouper.
Abstract The conventional design of steel structure objects relies on a first-order elastic analysis, where the entire object is treated as a set of individual structural elements requiring ...time-consuming, semi-empirical design calculations. Such an approach leads to inefficient design time and excessive material consumption and may additionally result in designing on the verge of structural safety. The AEC sector's technological and digitization advancement process forces designers to use advanced design methods. Hence, it is necessary to indicate the benefits of using effective optimization. The paper presents a comparative analysis of steel domes using two design approaches: traditional first-order analysis and an advanced second-order analysis. The latter method considers the influence of structural deformation on the magnitude of internal forces. Eight models were developed, varying in terms of the connection's stiffness. The work results identify the differences between the two selected design approaches and present opportunities for further structural performance of steel structures.
Batch kinetic test was performed for nine per- and polyfluoroalkyl substances (PFASs). Pseudo-first-order (PFO) and pseudo-second-order (PSO) kinetic models as well as the intraparticle diffusion ...(ID) model were used to determine the rate constants representing K.sub.1, K.sub.2, and K.sub.id, respectively. They were then compared to evaluate the effect of the carbon chain length and adsorption surface area (i.e., different powder activated carbon (PAC) concentrations) on the competing conditions of nine PFAS species. The lowest and average of coefficient of determination (R.sup.2) was 0.965 and 0.992, and 0.692 and 0.898 and for nonlinear and linear PFO, respectively, implying that linear PFO included extraordinary sample point. K.sub.1 increased by 3.6 times on average from 10 and to 100 mg/L of PAC. For nonlinear PFO, K.sub.1 increased up to 5.9 times (from 1.63 to 9.64) and 8.3 times (from 1.11 to 9.24) with the increase of the carbon chain length and PAC concentration, respectively. PSO obtained a higher average coefficient of determination (R.sup.2) of 0.996 than PFO of 0.992 determining PSO is more suitable than PFO. K.sub.2 was more affected than K.sub.1 by concentration of PAC based on linear and exponential quantitative correlations for K.sub.1 and K.sub.2, respectively, although the behavior of K.sub.2 was a very similar to K.sub.1 at all condition except for 100 mg/L of PAC. The value of K.sub.id showed an opposite pattern to those of K.sub.1 and K.sub.2, in which the sum of K.sub.id and C decreased from 3.67, 1.73, 0.816, and 19.2 to 15.1, 12.0, and 7.89 at 10, 30, 50, and 100 mg/L of PAC concentration, respectively, indicating that the effect of the film and intraparticle diffusions on the adsorption was not significant when there is higher interaction and enough surface area because, in this case, the process rapidly reaches equilibrium.
The potential of Ag/MgO/ Formula omitted-Al.sub.2O.sub.3 (Ag/Mg-Al) as a passive NO.sub.x adsorber is evaluated, and is found to be superior as compared to Ag/ Formula omitted-Al.sub.2O.sub.3. Two ...different adsorption sites exist on both Ag/Mg-Al and Ag/ Formula omitted-Al.sub.2O.sub.3, and it is inferred that the primary role of MgO is not to provide additional adsorption sites but to decrease the Ag particle size, which results in a higher activity towards NO.sub.x adsorption. The product distribution profile with either NO or NO.sub.2 in the feed is found to be nearly the same at early times, which indicates the formation of the same surface species with either of the reactants. It is deduced that the facile conversion of nitrites to nitrates occurs in the presence of H.sub.2, but the extent of conversion decreases at longer times. A sequential configuration of the in-house Ag/Mg-Al and a commercial Cu/SSZ-13 catalyst yielded a NO.sub.x reduction efficiency of 85% at low temperatures as against 7% with the standalone Cu/SSZ-13 catalyst. Graphic
In this paper, in order to improve the cooling power, the thermal effects of using titanium oxide nanoparticles with different concentrations and perforated nozzles with paddle blades are ...investigated. In this simulation, by presenting a new design for a Si-IGBT power module, three types of paddle blades with a simple nozzle type to pump cooling fluid are evaluated and compared. The boundary condition is that a constant heat flux enters from the top of the module, i.e., IGBT and the Diode. In order to further investigate the thermal effects, an attempt has been made to investigate the temperature of the module under a heat flux of 150 W cm.sup.-2, 180 W cm.sup.-2, 255 W cm.sup.-2, so that the IGBT heat flux is always higher than the Diode input flux. In this robust and three-dimensional simulation extracted from ANSYS-FLUENT commercial software, it was found that turbulent kinetic energy increases with increasing number of nozzle blades. At the same time, increasing the volume fraction of nanoparticles from 0.01 to 0.05 leads to improved heat transfer and ultimately reduces the thermal peak created in the study space. In addition, increasing the transverse mass flow rate improves cooling, which reduces the performance coefficient (COP) of the system.
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