1,721,170 research outputs found
Commentary: 3-Iodothyronamine Reduces Insulin Secretion In Vitro via a Mitochondrial Mechanism
Full text linkLehmphul et al. report the effect of 3-iodothyronamine in reducing insulin release in a model of
immortalized pancreatic β-cells. Notwithstanding the simplified β-cell model used, this article offers
an opportunity to reconsider, possibly under a new light, an old issue of research, which excited
people working on amine oxidases (AOs) in the last 20 years. Toward this aim, we would like to
propose some points of reflection to the scientific community working on 3-iodothyronamine and
thyroid hormone metabolites
Structural Growth Disengagement and value creation in small and micro-firms. Mapping pathologies and physiologies of business dwarfism in a dynamic resource-based view
Full text linkThis paper focuses growth disengagement, in the perspective of those firms who have been keeping their structures, processes and relational systems unchanged for a very long time. The implicit hypothesis according to which such businesses are affected by a structural disease, are not able to create any significant value, and characterised by similar features, is critically discussed. Through an analysis of the phenomenon in the business growth and dynamic resource-based-view, a first attempt taxonomy, based on case-studies, is sketched. It is demonstrated how the implicit assumption according to which such firms are affected by a pathological condition is false, at least if seen as an a priori statement
Predicting buckling resistance of two three-dimensional lattice architectures
Full text linkLattice structures are an important class of architected cellular solids and structures with high potential for multifunctional and lightweight applications. Novel technologies such as additive manufacturing have vastly extended the design freedom to develop such architectures. In this work, a reliable theoretical model for optimizing unit cell design against buckling is developed for two different cell architectures: pyramidal and tetrahedral. The model's accuracy was evaluated through extensive finite element analysis and compared to existing methods available in the literature
Mechanical performance of hybrid metal-composite joints reinforced with additive-manufactured stainless steel pins: a comparative study of pin geometry and fabric architecture
No full textThe design of robust hybrid joints between metal and composite parts is critical in multi-material structural applications. This study investigates the mechanical performance of single-lap joints reinforced with additively manufactured stainless steel pins featuring two geometries—spike (Type S) and ball-head (Type B)—embedded in unidirectional (UD) and twill (TW) carbon fiber-reinforced polymer (CFRP) laminates. Under quasi-static shear loading, ball-head pins increased peak load by up to 44% and failure energy by up to 66% compared to spike pins, with the Type B TW configuration achieving the highest energy dissipation. Microscopy revealed that fiber architecture and pin geometry jointly influenced failure mechanisms: TW laminates promoted distributed damage and bridging, while UD laminates exhibited localized fiber fracture and matrix splitting. These findings demonstrate that additive pinning strategies can be tailored to enhance strength and toughness in hybrid joints, and provide insight for the future design of durable metal–composite interfaces in aerospace and automotive applications
Structural Growth Disengagement and Entrepreneurship in Small and Micro-Firms. Mapping Pathologies and Physiologies of “Business Dwarfism” in a Dynamic Resource-Based-View
No full textThis paper focuses growth disengagement, in the perspective of those firms who have been keeping their structures, processes and relational systems unchanged for a very long time. The implicit hypothesis according to which such businesses are affected by a structural disease, are not able to create any significant value, and characterised by similar features, is critically discussed. Through an analysis of the phenomenon in the business growth and dynamic resource-based-view, a first attempt taxonomy, based on case-studies, is sketched. It is demonstrated how the implicit assumption according to which such firms are affected by a pathological condition is false, at least if seen as an a priori statement
The 3-iodothyronamine (T1AM) and the 3-iodothyroacetic acid (TA1) indicate a novel connection with the histamine system for neuroprotection
No full textThe 3-iodothyronamine (T1AM) and 3-iodothryoacetic acid (TA1), are endogenous occurring compounds structurally related with thyroid hormones (THs, the pro-hormone T4 and the active hormone T3) initially proposed as possible mediators of the rapid effects of T3. However, after years from their identification, the physio-pathological meaning of T1AM and TA1 tissue levels remains an unsolved issue while pharmacological evidence indicates both compounds promote in rodents central and peripheral effects with mechanisms which remain mostly elusive. Pharmacodynamics of T1AM includes the recognition of G-coupled receptors, ion channels but also biotransformation into an active metabolite, i.e. the TA1. Furthermore, long term T1AM treatment associates with post-translational modifications of cell proteins. Such array of signaling may represent an added value, rather than a limit, equipping T1AM to play different functions depending on local expression of targets and enzymes involved in its biotransformation. Up to date, no information regarding TA1 mechanistic is available. We here review some of the main findings describing effects of T1AM (and TA1) which suggest these compounds interplay with the histaminergic system. These data reveal T1AM and TA1 are part of a network of signals involved in neuronal plasticity including neuroprotection and suggest T1AM and TA1 as lead compounds for a novel class of atypical psychoactive drugs. © 2021 Elsevier B.V.
3-Iodothyroacetic acid; 3-Iodothyronamine; Histamine; Neuroprotection; Thyroid hormone-related compounds; Thyroid hormone
Enhancing the Robustness of Hybrid Metal-Composite Connections Through 3D Printed Micro Penetrative Anchors
Full text linkThis work proposes a novel solution for manufacturing hybrid metal-composite joints, in which different pin shapes are evaluated for their capability to penetrate long carbon fiber epoxy composites successfully and for the mechanical behavior determined by each configuration. On the metal side, pins are manufactured by Laser Powder Bed Fusion (LPBF), downsizing the currently adopted solutions and, at the same time, developing new blocking features aimed at enhancing the mechanical properties of the joint. The different configurations were evaluated in two distinct experiments: the first to evaluate the induced defects in the composite substrate and the second to characterize the mechanical behavior of the joint. It emerges that smaller pins produce much less damage and misalignments in the composite structure with respect to the conventional pin solution, whereas the new “blocking features” configurations consistently increase maximum pullout load and energy with respect to the conventional pin solution, with the same level of fiber damage
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Krein's resolvent formula for self-adjoint extensions of symmetric second-order elliptic differential operators
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