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A systematic investigation to understand the use of a novel axial impeller as a part of counter-rotating axial compressor to compress water vapor as refrigerant was undertaken. Blade angle was investigated at first to understand this novel impeller’s geometry. A commercial CFD package, which solves the Reynolds-averaged Navier–Stokes equations, was used to compute the complex flow field of the impeller. Two hub/shroud tip ratios with different speed ratios were numerically simulated. The numerical simulation focused on the water vapor flow from compressor impeller inlet to outlet and the overall performance level and range were predicted. The numerical investigation revealed that at hub/shroud tip ratio of 0.54, maximum pressure ratio reached about 1.24 with isentropic efficiency around 75\% at its design point. Detailed investigation into flow structure showed that a serious secondary flow exists between span ranges of 30–50\%. An enlargement of hub/shroud tip ratio to 0.75 showed that pressure ratio had been improved significantly. By comparing different speed ratios and hub/shroud tip ratios, the study shows potential to utilize this novel axial impeller to compress water vapor as refrigerant.

The neurobiological processes involved in establishing sleep regulation are vulnerable to environmental exposures as early as seven weeks of gestation. Studies have linked in utero pesticide exposure to childhood sleep-disordered breathing. However, the impact of in utero pesticide exposure on the sleep health of adolescents remains unexplored.Data from 137 mother-adolescent pairs from a Mexico City cohort were analyzed. We used maternal urinary 3-phenoxybenzoic acid (3-PBA, pyrethroid metabolite) and 3, 5, 6-trichloro-2-pyridinol (TCPy, chlorpyrifos metabolite) from trimester three to estimate in utero pesticide exposure. Among adolescents, we obtained repeated measures of objectively assessed sleep duration, midpoint, and fragmentation using wrist-actigraphy devices for 7 consecutive days in 2015 and 2017. Unstratified and sex-stratified associations between maternal urinary 3-PBA and TCPy and adolescent sleep measures were examined using generalized linear mixed models (GLMMs). We also examined the interactive effects of maternal pesticide exposure and offspring sex on sleep outcomes.3-PBA and TCPy were detected in 44.4% and 93% of urine samples, respectively. Adjusted findings demonstrated that higher exposure to maternal TCPy was associated with longer sleep duration and later sleep timing. Findings from interaction tests between maternal pesticide exposure and offspring sex were not statistically significant, although adjusted sex-stratified findings showed that the association between TCPy with duration and midpoint was evident only among female offspring. To illustrate, those in the highest tertile of exposure had a 59 minute (95% CI: 12.2, 104.8) (p, trend = 0.004) longer sleep duration and a 0.6 hour (95% CI: 0.01, 1.3) (p, trend = 0.01) later sleep midpoint. We found no significant associations between 3-PBA and sleep outcomes.Within a cohort of mother-adolescent pairs, we found associations between maternal prenatal pesticide exposure and longer sleep duration and later sleep timing among adolescent offspring. Further, this association may be female-specific.

Research on the evolutionary ecology of urban areas reveals how human-induced evolutionary changes affect biodiversity and essential ecosystem services. In a rapidly urbanizing world imposing many selective pressures, a time-sensitive goal is to identify the emergent issues and research priorities that affect the ecology and evolution of species within cities. Here, we report the results of a horizon scan of research questions in urban evolutionary ecology submitted by 100 interdisciplinary scholars. We identified 30 top questions organized into six themes that highlight priorities for future research. These research questions will require methodological advances and interdisciplinary collaborations, with continued revision as the field of urban evolutionary ecology expands with the rapid growth of cities.

Through means of 3-D CFD (Computational Fluid Dynamics) method, a novel axial compressor with different impeller shapes compressing water vapor as refrigerant was investigated. The numerical simulation focuses on the fluid flow from compressor impeller inlet to outlet. The overall performance level and range are predicted. Different blade patterns with different hub sizes were compared regarding the aerodynamic performance. Independent of the blade pattern, in this numerical investigation the largest hub diameter shows the highest pressure ratio and efficiency at narrowest operating range.

Numerical applications implemented on the Monte Carlo method have developed in line with the increase of computer power; nowadays, in the field of nuclear reactor physics, it is possible to perform burnup simulations in a detailed 3D geometry and a continuous energy description by the Monte Carlo method; moreover, the required computing time can be abundantly reduced by taking advantage of a computer cluster. In this paper we focused on comparing the results of the two major Monte Carlo burnup codes, MONTEBURNS and MCB, when they share the same MCNP geometry, nuclear data library, core thermal power, and they apply the same refueling and shuffling schedule. While simulating a total operation time of the Gas Turbine-Modular Helium Reactor of 2100 effective full power days and a one-pass deep burn in-core fuel management schedule, we have found that the two Monte Carlo codes produce very similar results both on the criticality value of the core and the transmutation of the key actinides.

Przedstawiono metody wytwarzania, charakterystykę i wykorzystanie CaO unieruchomionego na polimerowych matach jako przyjaznego środowisku katalizatora stosowanego w produkcji biodiesla. Maty zbudowane z włókien poliakrylonitrylu (PAN) zostały stworzone z zastosowaniem procesu elektro-hydrodynamicznego (EHD), popularnie zwanego elektroprzędzeniem, gdzie CaO unieruchomiono poprzez fizyczne wiązanie na włóknach polimeru oraz chemicznie wiążąc go za pomocą linkera zbudowanego z dopaminy. Katalizator unieruchomiony tymi dwiema metodami został następnie z sukcesem wykorzystany w reakcji transestryfikacji oleju rzepakowego i produkcji biodiesla. Cząstki CaO mechanicznie związane z włóknami PAN można było wykorzystać nawet do 6 razy w reakcjach konwersji triglicerydów do biodiesla, kiedy katalizator chemicznie unieruchomiony na polimerowej macie nie dawał możliwości ponownego wykorzystania. Zastosowanie techniki EHD w procesie pozwoliło na stworzenie łatwo separowalnego katalizatora możliwego do wielokrotnego wykorzystania w procesie transestryfikacji. We describe the design, creation, and usage of a CaO catalyst immobilized onto polymeric mats for environmentally-friendly biodiesel production. The polyacrylonitrile (PAN) fiber mats were prepared by electro-hydrodynamic processing (EHD), commonly known as electrospinning or electrospraying, in which immobilized CaO particles were either physically entrapped on the fibers or chemically bound onto the fiber surface by a dopamine linkage. These two catalyst materials were later successfully used in the transesterification of fresh canola oil into biodiesel. Mechanically entrapped CaO particles in the PAN fibers were able to be re-used up to six times in the conversion of triglycerides into biodiesel, while the chemically immobilized catalyst was found impossible to reuse. The use of EHD processing allows us to create an easily separable, reusable catalyst that could be commonly used in transesterification reactions.

Lymphatic spread is an important pathway of progression in non-small-cell lung cancer (NSCLC), along with local spread and distant metastasis. The probability of lymph node (LN) involvement is dependent on the site of the primary tumor, stage, and histology. Elective nodal irradiation (ENI) is the irradiation of clinical and radiological uninvolved LN to account for microscopic tumor invasion in these LNs because we have not been able to determine the extent of LN spread accurately. The clinical value of ENI is uncertain. The impact of ENI is dependent on many (staging-, treatment-, and patient-related) factors. The purpose of this report is to analyze the current status of ENI and to provide comprehensive in-depth analysis and guidance on how to generally approach this issue in NSCLC.

Pressure wave devices use shock waves to transfer energy directly between fluids without additional mechanical components, thus having the potential for increased efficiency. The wave rotor is a promising technology which uses shock waves in a self-cooled dynamic pressure exchange between fluids. For high-pressure, high-temperature topping cycles, it results in increased engine overall pressure and temperature ratio, which in turn generates higher efficiency and lower specific fuel consumption. Designing a wave rotor mainly focuses on predicting the behavior of shock and expansion waves. The extant literature presents numerous examples of wave rotor designs, but most of them rely on complicated numerical analyses as well as computer code developed specifically for this application. This paper presents an initial scheme used for designing wave rotors employing thermodynamic and gasdynamic analysis as well as computational fluid dynamic analysis. Basic theory and a simplified model of the wave rotor are used to predict the travel time and strength of waves. The model is then refined using a more advanced numerical scheme on the basis of the Lax–Wendroff method and FLUENT, a commercial CFD code.