A laboratory study of caching in Desmodillus auricularis

No Abstrac

Production of polylactic acid aerogels via phase separation and supercritical CO2_{2} drying: thermodynamic analysis of the gelation and drying process

The application range of aerogels, especially in the life-science sector, can be extended by utilizing biocompatible polymers such as polylactic acid (PLA). However, the low glass transition temperature (Tg) of PLA and the challenging gelation techniques limit the application of supercritical CO$_{2}$ (scCO$_{2}$) drying and thus the PLA-aerogel production. The aim of this work is to overcome this challenge and to provide a better understanding of the thermodynamics of the process. Therefore, the gelation of amorphous PLA (PDLLA) and semicrystalline PLA (PLLA) via thermal-induced phase separation (TIPS) was studied. To identify polymer/solvent/antisolvent ratios suitable for gelation, thermodynamic modeling (PC-SAFT) was used to describe the corresponding ternary phase diagrams. scCO$_{2}$ drying was used to preserve the mesoporous gel structure formed during the gelation. Due to the decrease in the Tg of PLA in the presence of CO$_{2}$, this could not be applied to all gels. It was found that the critical parameter to enable the scCO$_{2}$ drying of low Tg polymers is the crystallinity degree (Xc) of the polymer. Based on these results, some guidelines for producing aerogels from polymers with low Tg are formulated

Advanced Denoising for X-ray Ptychography

The success of ptychographic imaging experiments strongly depends on achieving high signal-to-noise ratio. This is particularly important in nanoscale imaging experiments when diffraction signals are very weak and the experiments are accompanied by significant parasitic scattering (background), outliers or correlated noise sources. It is also critical when rare events such as cosmic rays, or bad frames caused by electronic glitches or shutter timing malfunction take place. In this paper, we propose a novel iterative algorithm with rigorous analysis that exploits the direct forward model for parasitic noise and sample smoothness to achieve a thorough characterization and removal of structured and random noise. We present a formal description of the proposed algorithm and prove its convergence under mild conditions. Numerical experiments from simulations and real data (both soft and hard X-ray beamlines) demonstrate that the proposed algorithms produce better results when compared to state-of-the-art methods.Comment: 24 pages, 9 figure

3D multimodal teaching of human anatomy and autopsy with real human data

With advances in digitalization, the industrial, education, and research sectors have made use of novel methods to train their staff and students. Simulations and visualizations of real-life situations allow effective and tailored learning strategies. In medicine, the advancement of three-dimensional (3D) surface documentation technologies, particularly close-range photogrammetry, are used to document pathologies or procedural steps in 3D. Subsequently created 3D models enhanced by adding annotations, incision lines, explanations, and animations can be used for educational purposes. In this paper, we describe possible ways to improve or extend actual learning methods in medical teaching and show a concept for possible application. As various teaching tools already exist, we aim to add a teaching approach using 3D visualization. Therefore, a forensic dissection of the neck was documented in 3D, annotated and prepared for teaching using animated videos, 3D PDFs and virtual reality. In the future, the dissection of each body part and organ will be documented using the procedure presented in this paper. The aim of this method is to provide a technique to teach human anatomy and autopsy steps to both medical students and forensic pathologists

Current Challenges for Preschool Primary Education

Challenges for elementary and primary education in many areas neither occur in isolation nor are limited to individual states but often represent themselves as area-wide and complex problem situations. The text discusses how to deal with a heterogeneous student body in elementary schools, which has been exacerbated by immigration in recent years. The focus of reflection is on individual, instructional, and organizational approaches to make educational processes as fruitful as possible for all children

Управление процессом дуговой сварки покрытыми электродами воздействием на параметры режима

В процессе проведения экспериментальных исследований определена степень влияния импульсного изменения энергетических параметров на стабильность тепломассопереноса при дуговой сварке и наплавке покрытыми электродами. Определено влияние амплитудно-временных параметров режима на условия формирования сварного шва и наплавленного металла, а также критерии выбора специализированного сварочного оборудования.In the course of experimental studies, the degree of influence of the pulse change of energy parameters on the stability of heat and mass transfer in arc welding and surfacing with covered electrodes is determined. The influence of the amplitude-time parameters of the regime on the conditions of formation of the weld and weld metal, as well as the criteria for the selection of specialized welding equipment

Environmental calcium and variation in yolk sac size influence swimming performance in larval lake sturgeon (Acipenser fulvescens)

In many animal species, performance in the early life stages strongly affects recruitment to the adult population; however, factors that influence early life history stages are often the least understood. This is particularly relevant for lake sturgeon, Acipenser fulvescens, living in areas where environmental calcium concentrations are declining, partly due to anthropogenic activity. As calcium is important for muscle contraction and fatigue resistance, declining calcium levels could constrain swimming performance. Similarly, swimming performance could be influenced by variation in yolk sac volume, because the yolk sac is likely to affect drag forces during swimming. Testing swimming performance of larval A. fulvescens reared in four different calcium treatments spanning the range of 4-132 mg l-1 [Ca2+], this study found no treatment effects on the sprint swimming speed. A novel test of volitional swimming performance, however, revealed reduced swimming performance in the low calcium environment. Specifically, volitionally swimming larvae covered a shorter distance before swimming cessation in the low calcium environment compared to the other treatments. Moreover, sprint swimming speed in larvae with a large yolk sac was significantly slower than in larvae with a small yolk sac, regardless of body length variation. Thus, elevated maternal allocation (i.e., more yolk) was associated with reduced swimming performance. Data suggest that larvae in low calcium environments or with a large yolk sac exhibit reduced swimming performance and could be more susceptible to predation or premature downstream drift. Our study reveals how environmental factors and phenotypic variation influence locomotor performance in a larval fish