Induction of flowering and seed production in ecotypes of Festuca hallii

Non-Peer Reviewe

High fracture toughness micro-architectured materials

© 2020 We investigate the possibility of achieving high fracture toughness and high strength by the design of lightweight (density below water) metallic micro-architectured materials. The micro-architectured materials were manufactured by drilling a hexagonal array of holes in plates of an aluminum alloy, and the fracture toughness was evaluated via three-point bend tests of single-edge notch specimens. The results show that the fracture toughness of micro-architectured materials increases with increasing relative density and remarkably, a micro-architectured material can be 50% lighter than the parent material but maintain the same fracture toughness. Additional tests on geometrically similar specimens revealed that the fracture toughness increases linearly with the square-root of the cell size. The experiments are complemented by finite element calculations of ductile fracture. In the calculations, the fracture toughness of single-edge notch specimens subjected to three-point bending are evaluated using both, a procedure similar to the experiments and direct computation of the J-contour integral. The fracture toughness as calculated by both methods are consistent with the experimental results. In addition, the calculations are also carried out for single-edge notch specimens subjected to tensile loading, confirming the validity of the measured fracture toughness as a useful material property independent of specimen geometry

Bioenergetic-active materials enhance tissue regeneration by modulating cellular metabolic state

Cellular bioenergetics (CBE) plays a critical role in tissue regeneration. Physiologically, an enhanced metabolic state facilitates anabolic biosynthesis and mitosis to accelerate regeneration. However, the development of approaches to reprogram CBE, towards the treatment of substantial tissue injuries, hasbeen limited thus far. Here, we show that induced repair in a rabbit model of weight-bearing bone defects is greatly enhanced using a bioenergetic-active material (BAM) scaffold, compared to commercialized poly (lactic acid) and calcium phosphate ceramic scaffolds. This material was composed of energy-active units that can be released in a sustained degradation-mediated fashion once implanted. By establishing an intramitochondrial metabolic bypass, the internalized energy-active units significantly elevatemitochondria membrane potential (ΔΨm) to supply increased bioenergetic levels and accelerate bone formation. The ready-to-use material developed here represents a highly efficient and easy-to-implement therapeutic approach toward tissue regeneration, withpromise for bench-to-bedside translation

A Quasi-Classical Model of Intermediate Velocity Particle Production in Asymmetric Heavy Ion Reactions

The particle emission at intermediate velocities in mass asymmetric reactions is studied within the framework of classical molecular dynamics. Two reactions in the Fermi energy domain were modelized, $^{58}$Ni+C and $^{58}$Ni+Au at 34.5 MeV/nucleon. The availability of microscopic correlations at all times allowed a detailed study of the fragment formation process. Special attention was paid to the physical origin of fragments and emission timescales, which allowed us to disentangle the different processes involved in the mid-rapidity particle production. Consequently, a clear distinction between a prompt pre- equilibrium emission and a delayed aligned asymmetric breakup of the heavier partner of the reaction was achieved.Comment: 8 pages, 7 figures. Final version: figures were redesigned, and a new section discussing the role of Coulomb in IMF production was include

Tissue iron distribution assessed by MRI in patients with iron loading anemias

Bone marrow, spleen, liver and kidney proton transverse relaxation rates (R2), together with cardiac R2* from patients with sickle cell disease (SCD), paroxysmal nocturnal hemoglobinuria (PNH) and non-transfusion dependent thalassemia (NTDT) have been compared with a control group. Increased liver and bone marrow R2 values for the three groups of patients in comparison with the controls have been found. SCD and PNH patients also present an increased spleen R2 in comparison with the controls. The simultaneous measurement of R2 values for several tissue types by magnetic resonance imaging (MRI) has allowed the identification of iron distribution patterns in diseases associated with iron imbalance. Preferential liver iron loading is found in the highly transfused SCD patients, while the low transfused ones present a preferential iron loading of the spleen. Similar to the highly transfused SCD group, PNH patients preferentially accumulate iron in the liver. A reduced spleen iron accumulation in comparison with the liver and bone marrow loading has been found in NTDT patients, presumably related to the differential increased intestinal iron absorption. The correlation between serum ferritin and tissue R2 is moderate to good for the liver, spleen and bone marrow in SCD and PNH patients. However, serum ferritin does not correlate with NTDT liver R2, spleen R2 or heart R2*. As opposed to serum ferritin measurements, tissue R2 values are a more direct measurement of each tissue's iron loading. This kind of determination will allow a better understanding of the different patterns of tissue iron biodistribution in diseases predisposed to tissue iron accumulation

‘I had to pop a wheelie and pay extra attention in order not to fall:’ embodied experiences of two wheelchair tennis athletes transgressing ableist and gendered norms in disability sport and university spaces

When bodies move in certain contexts, it can mean very different things for different people. In our society, some bodies are more valued than others, and detrimentally, this can mean that certain types of bodies are ostracised and segregated to the outskirts of production economies and society. Dis/ability sport spaces, able-bodied sports spaces and able-bodied university spaces have been an under-researched area when considering how the body moves throughout these spaces for elite wheelchair athletes taking part in university courses. To learn more, this paper drew on feminist poststructuralism and new materialist perspectives and shared an insight into how two athletes with dis/abilities transgressed abled and gendered norms in different spaces and how they positioned themselves as athletic bodies and disabled bodies in these spaces. Employing a post-critical ethnographic design, we found that dependent on the space a dis/abled body is in constant flux as to when it feels marginalised and different (typically able-bodied spaces) and when it feels included, valued, and strong (typically dis/abled spaces). Significantly, the materiality of the institutional structures of universities, founded upon historic aesthetics of beauty dictated the physical spaces the athletes entered and created spaces of exclusion based on capitalist and ableist ideologies

Metabolic effects of overnight continuous infusion of unacylated ghrelin in humans

Objective: To clarify the metabolic effects of an overnight i.v. infusion of unacylated ghrelin (UAG) in humans. UAG exerts relevant metabolic actions, likely mediated by a still unknown ghrelin receptor subtype, including effects on β-cell viability and function, insulin secretion and sensitivity, and glucose and lipid metabolism. Design: We studied the effects of a 16-h infusion (from 2100 to 1300 h) of UAG (1.0 μg/kg per h) or saline in eight normal subjects (age (mean±S.E.M.), 29.6±2.4 years; body mass index (BMI), 22.4±1.7 kg/m2), who were served, at 2100 and 0800 h respectively, with isocaloric balanced dinner and breakfast. Glucose, insulin, and free fatty acid (FFA) levels were measured every 20 min. Results: In comparison with saline, UAG induced significant (P<0.05) changes in glucose, insulin, and FFA profiles. UAG infusion decreased glucose area under the curve (AUC) values by 10% (UAG0-960 min: 79.0±1.7×10 3 mg/dl per min vs saline0-960 min: 87.5±3. 8×103 mg/dl per min) and the AUC at night by 14% (UAG 180-660 min: 28.4±0.5×103 mg/dl per min vs saline180-660 min: 33.2±1.1×103 mg/dl per min). The overall insulin AUC was not significantly modified by UAG infusion; however, insulin AUC observed after meals was significantly increased under the exposure to UAG with respect to saline at either dinner or breakfast. The FFA AUC values were decreased by 52% under the exposure to UAG in comparison with saline (UAG0-960 min: 0.3±0.02×103 mEq/l per min vs saline0-960 min: 0.6±0.05×103 mEq/l per min). Conclusions: Exposure to the i.v. administration of UAG improves glucose metabolism and inhibits lipolysis in healthy volunteers. Thus, in contrast to the diabetogenic action of AG, UAG displays hypoglycemic properties