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Background: Drafting for drag reduction is a tactic commonly employed by elite athletes of various sports. The strategy has been adopted by Kenyan runner Eliud Kipchoge on numerous marathon events in the past, including the 2018 and 2022 editions of the Berlin marathon (where Kipchoge set two official world records), as well as in two special attempts to break the 2 h mark for the distance, the Nike Breaking2 (2017) and the INEOS 1:59 Challenge (2019), where Kipchoge used an improved drafting formation to finish in 1:59:40, although that is not recognized as an official record. Results: In this study, the drag of a realistic model of a male runner is calculated by computational fluid dynamics for a range of velocities. The formations employed in the past by Kipchoge, as well as alternative formations, are analyzed and systematically compared with respect to mechanical power. In a quest to show that running an official marathon in under 2 h is possible, the power analysis is extended to the pacers. We developed a simple drafting and pacing strategy that Kipchoge could have used to run the 2022 Berlin marathon in a surprising 1 h, 59 min and 48 s. Conclusions: Elite marathon runners can make better use of the pacers to experience reduced drag in races. The associated energy reduction makes it possible to run faster, finishing the race in less time. Using a better drafting strategy and a positive splitting pacing strategy, Kenyan runner Eliud Kipchoge could have broken the sub 2 h barrier in both the 2018 and 2022 editions of Berlin Marathon. [ABSTRACT FROM AUTHOR]

Motivated by the 2022 worldwide Monkeypox (MPox) outbreak, a compartmental model is proposed to predict the evolution of the disease. Numerous models have been proposed for infectious diseases so far, although the number of variables makes it difficult to establish causation relations between individual factors and transmission rates. In order to evaluate the reaction of susceptible people to avoid infection during the outbreak, the rate of transmission is modeled through a unique phenomenological probabilistic approach, allowing the expression of the rate of generation of new cases in terms of two characteristics of the susceptible group: the frequency of sexual encounters and the probability of transmission given that there is a sexual encounter. Transmission rates are obtained and compared for the U.S. and several other countries. Results show reductions of up to 71% in the transmissibility parameter, which may be combined with variations in the frequency of sexual encounters (obtained through behavioral research) to determine the changes in the probability of transmission during an outbreak in a much more convenient way than current alternatives. This framework presents a valuable tool to health authorities in the understanding of future sexually transmissible disease outbreaks. [ABSTRACT FROM AUTHOR]

This study investigates and compares the thermal phase transition and crystallization characteristics of a commercial food grade free phytosterol blend (FP) with a stigmasterol analytical standard (SS), the FP behavior in a food model system after its addition to high oleic sunflower oil (HOSO). The properties of the FP:HOSO blends were studied by differential scanning calorimetry, solid content, crystal morphology, and X-ray diffraction (XRD) measurements. The Rietveld method (RM) was applied associated with the XRD measurements to support phase analysis and the study of crystallinity degree. The materials were also characterized by means of chemical composition, such as fatty acids and triacylglycerol profiles, for HOSO, and phytosterol profile, for FP. Regarding phase behavior and crystallinity properties, FP has very similar characteristics to SS. The thermal behavior of FP:HOSO blends has two characteristic peaks, one from FP and the other from HOSO. The similarity reported in the literature between the diffraction pattern of FP and pure phytosterols is a positive characteristic for FP. A high FP concentration resulted in high supersaturation and thus the formation of small crystals. The incorporation of HOSO reduced of the large agglomeration of FP crystals and the dispersion crystalline aggregates (spherulites) of FP crystals. The application of RM in FP:HOSO blends to quantify the crystalline and amorphous phases was successfully used. The application has provided the expected value for these phases, according to the same experimental mass ratio of the blends, thereby validating the applicability of this approach in this type of material., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Hemidecortication, which consists of removing one cerebral hemisphere, leaving intact the thalamus and hypothalamus, affects the hypothalamus-hypophyseal axis producing hypothyroidism. Hemidecorticate rats showed a significant decrease in the weekly eruption rate of the upper incisors and partial recovery after the administration of thyrotrophin-releasing hormone (TRH). The uptake of [3H]-glycine, 1 and 4 h after a single injection, shown by radioautography, was 25 to 50 per cent higher in the periodontal ligament of the experimental animals. Most of the labelled material was non-collagenous proteins because only 20 to 30 per cent was removed by collagenase.