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Optimal thermal management system design is critical for power electronic converters to ensure the reliability of power semiconductor switches. Medium power density inverter systems are often air-cooled to ensure an efficient and cost-effective thermal management solution. In addition, using heat pipes as the heat transfer medium between the heat sources and the heat sink can provide lower volume for the entire inverter. This paper investigates the effectiveness of Teaching Learning Based Optimization (TLBO) for finding the optimal forced-air heat sink with heat pipe cooling system to achieve higher fan efficiency and lower inverter packaging volume. The optimal design is found utilizing commercially available fans and heat pipes. The TLBO design optimization is also compared to the highly implemented Particle Swarm Optimization (PSO) and it is found that TLBO uses 20 times fewer iterations than PSO to converge, and that the TLBO results are more robust for different design constraints.

We consider the following elliptic system ��u =\nabla H (u) \ \ \text{in}\ \ \mathbf{R}^N, where $u:\mathbf{R}^N\to \mathbf{R}^m$ and $H\in C^2(\mathbf{R}^m)$, and prove, under various conditions on the nonlinearity $H$ that, at least in low dimensions, a solution $u=(u_i)_{i=1}^m$ is necessarily one-dimensional whenever each one of its components $u_i$ is monotone in one direction. Just like in the proofs of the classical De Giorgi's conjecture in dimension 2 (Ghoussoub-Gui) and in dimension 3 (Ambrosio-Cabr��), the key step is a Liouville theorem for linear systems. We also give an extension of a geometric Poincar�� inequality to systems and use it to establish De Giorgi type results for stable solutions as well as additional rigidity properties stating that the gradients of the various components of the solutions must be parallel. We introduce and exploit the concept of {\it an orientable system}, which seems to be key for dealing with systems of three or more equations. For such systems, the notion of a stable solution in a variational sense coincide with the pointwise (or spectral) concept of stability. 12 pages, improved on the earlier versions. Updated version - if any - can be downloaded at http://www.birs.ca/~nassif/

Webs are certain planar diagrams embedded in disks. They index and describe bases of tensor products of representations of s l 2 \mathfrak {sl}_2 and s l 3 \mathfrak {sl}_3 . There are explicit bijections between webs and certain rectangular tableaux. Work of Petersen–Pylyavskyy–Rhoades (2009) and Russell (2013) shows that these bijections relate web rotation to tableau promotion. We describe the analogous relation between web reflection and tableau evacuation.

Abstract. Atmospheric aerosol particles span orders of magnitude in size. In ultrafine particles, the energetic contributions of surfaces and interfaces to the Gibbs energy become significant and increase in importance as particle diameter decreases. For these particles, the thermodynamic equilibrium state depends on size, composition, and temperature. Various aerosol systems have been observed to undergo liquid–liquid phase separation (LLPS), impacting equilibrium gas–particle partitioning, modifying physicochemical properties of the particle phases, and influencing cloud droplet activation. Numerous laboratory experiments have characterized the onset relative humidity of LLPS in larger aerosol particles and macroscopic bulk systems. However, in sufficiently small particles, the interfacial tension between two liquid phases constitutes an energetic barrier that may prevent the formation of an additional liquid phase. Determining said small-size limit is a key question. We introduce a predictive droplet model based on the Aerosol Inorganic–Organic Mixtures Functional groups Activity Coefficients model. This model enables size-dependent computations of surface and interfacial tension effects on bulk–surface partitioning within phase-separated and single-phase particles. We evaluate four approaches for computing interfacial tension in multicomponent droplets, including a new method introduced in this work. Of the approaches tested, Antonov's rule best matches observed liquid–liquid interfacial tensions in highly immiscible mixtures, while a modified Butler equation fits well in more miscible systems. We find that two approaches substantially lower the onset relative humidity of LLPS for the studied systems.

The global shift toward green energy alternatives escalates demands for new resources, including rare earth elements (REEs), as per their implications in various green innovations. However, our understanding of their environmental cycle, especially the interactions with aquatic organisms, remains deficient, ultimately hindering environmental protection efforts. Here, we investigate the accumulation of REEs and 18 other elements in bulk and sorted plankton collected with different net mesh sizes (30, 63, 200, 333, 500 μm) in the Estuary and Gulf of St. Lawrence in the summer and winter of 2020. We observed significant correlations between the concentrations of REEs and elements of different charge numbers and ionic radii (Ba, Co, Cs, Fe, Mn, Pb, Rb and V), indicating non-selective uptake of REEs into plankton. All these elements have their highest concentrations in the fluvial corridor and upper estuary, with more significant enrichment in phytoplankton ([La] = 26.4 ± 4.8 mg kg

A biodegradable polymer-based approach enables vertical and horizontal assembly of living tissues in a single step using a hook and look mechanism.

Device‐guided slow breathing has been tested in clinical populations (e.g., hypertension, type II diabetes) with the goal of reducing blood pressure (BP) via a sensitization of the baroreflex. The FitBit's “Relax Mode” and the RESPeRATE device are commercially available devices which acutely reduce an individual's respiration rate and, by extension, BP. To the best of our knowledge no studies have directly compared the cardiorespiratory effects of these devices. The purpose of this study was to compare acute respiratory and BP responses to the RESPeRATE device (RESP), the FitBit's Relax Mode (FB). We hypothesized that RESP would result in greater decreases in respiratory rate than FB, leading to larger decreases in BP. We evaluated the responses to a single bout of RESP (15 min) and FB (5 min) in young (mean±SD age: 23±1 y), healthy (BMI: 23±3 kg/m2; mean arterial BP [MAP]: 82±8 mmHg) individuals (n=2 men, n=3 women). To normalize the duration of the stimuli, we compared the mean of the responses to FB to the mean of the last 5 min of RESP; the order of devices was randomized between subjects. Both devices were effective in reducing respiration rate from baseline (RESP: 11.1±3.5 to 5.6±0.7 breaths/min; FB: 11.2±1.8 to 7.3±0.3; main effect of slow breathing: p<0.01; effect of device: p=0.4). In contrast, tidal volume expansion increased from baseline during slow breathing (RESP: 0.70±0.33 to 1.41±0.50 L; FB: 0.61±0.17 to 1.20±0.59; main effect of slow breathing: p<0.01; effect of device: p=0.6). However, there was no change in minute ventilation from baseline levels (RESP: 7.0±1.8 to 7.8±3.0 L/min; FB: 6.7±1.8 to 8.7±4.2; main effect of slow breathing: p=0.1; effect of device: p=0.9), suggesting that the subjects did not hyperventilate during either slow breathing condition. MAP decreased from baseline during slow breathing (RESP: 82±8 to 80±8 mmHg; FB: 82±8 to 81±7; main effect of slow breathing: p=0.01; effect of device: p=0.9). Conversely, a significant slow breathing by device interaction (p=0.05) revealed that diastolic BP (DBP) was reduced from baseline only in the RESP condition (69±7 to 67±8 mmHg, p<0.01); FB was not associated with a reduction in DBP (69±8 to 69±8 mmHg, p=0.2). Our preliminary data indicated that while RESP reduced respiratory rate similarly to the FB, RESP may be more effective than FB at acutely reducing DBP in young healthy adults.Support or Funding InformationThis project was supported by a Natural Sciences and Engineering Research Council Discovery Grant (CWU). TEA & YC were supported by the McGill Department of Kinesiology and Physical Education Graduate Excellence Fellowship.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

AbstractEgg protein is responsible for the second most serious of all food allergens, which affects predominantly the children. Therefore, a new type of vegan ingredient called “aquafaba,” is getting recognized as a plant‐based emulsifier in many bakery product preparations instead of the conventionally used egg white and is emerging in the consumer market. It is the residue water from cooked chickpeas. In this study, an I‐optimal mixture experimental design is combined with a response surface methodology to evaluate the chickpeas cooking process for obtaining aquafaba. The following variables were used: chickpea to cooking water ratio (CPCWR; 1:2, 1:4, and 2:3) and cook time (15, 30, 45, and 60 min). The principal goal was to maximize the functional properties and protein content, while minimizing tannin and phytate contents of aquafaba. The results showed that both CPCWR and cooking time had significant effect on the responses. Emulsion properties were the maximum at 2:3 CPCWR and cooking time of 60 min. Foaming capacity was highest (120%) at 2:3 CPCWR cooked for 30 min, whereas the foam was most stable (57 min) at 1:2 CPCWR with 45 min cooking. Water holding capacity reached the maximum level when cooked for 15 min, and oil holding capacity maximum was obtained after 60 min cooking. Polynomial models were developed for all 11 responses. Optimal results were achieved under the following conditions: 1.5:3.5 CPCWR and 60 min cook time, and the overall desirability fraction was 0.81. Validation tests confirmed these results.