Search results for "multidisciplinary"
showing 10 items of 4640 documents
A unified view of ligand-protected gold clusters as superatom complexes
2008
Synthesis, characterization, and functionalization of self-assembled, ligand-stabilized gold nanoparticles are long-standing issues in the chemistry of nanomaterials. Factors driving the thermodynamic stability of well documented discrete sizes are largely unknown. Herein, we provide a unified view of principles that underlie the stability of particles protected by thiolate (SR) or phosphine and halide (PR 3 , X) ligands. The picture has emerged from analysis of large-scale density functional theory calculations of structurally characterized compounds, namely Au 102 (SR) 44 , Au 39 (PR 3 ) 14 X 6 − , Au 11 (PR 3 ) 7 X 3 , and Au 13 (PR 3 ) 10 X 2 3+ , where X is either a halogen or a thiol…
Unique distal size selectivity with a digold catalyst during alkyne homocoupling
2015
Metal-catalysed chemical reactions are often controlled by steric hindrance around the metal atom and it is rare that substituents far away of the reaction site could be differentiated during reaction, particularly if they are simple alkyl groups. Here we show that a gold catalyst is able to discriminate between linear carbon alkynes with 10 or 12 atoms in the chain during the oxidative homocoupling of alkynes: the former is fully reactive and the latter is practically unreactive. We present experimental evidences, which support that the distal size selectivity occurs by the impossibility of transmetallating two long alkyl chains in an A-framed, mixed-valence digold (I, III) acetylide compl…
Effects of solar irradiance noise on a complex marine trophic web
2022
AbstractThe analysis of experimental data of the solar irradiance, collected on the marine surface, clearly highlights the intrinsic stochasticity of such an environmental parameter. Given this result, effects of randomly fluctuating irradiance on the population dynamics of a marine ecosystem are studied on the basis of the stochastic 0-dimensional biogeochemical flux model. The noisy fluctuations of the irradiance are formally described as a multiplicative Ornstein-Uhlenbeck process, that is a self-correlated Gaussian noise. Nonmonotonic behaviours of the variance of the marine populations’ biomass are found with respect to the intensity and the autocorrelation time of the noise source, ma…
An Examination of the Role and Responsibilities of Kindergarten in Multidisciplinary Collaboration on Behalf of Children With Severe Disabilities
2014
The purpose of this study was to examine the role and responsibilities of Norwegian kindergarten (i.e., preschool for ages 0–6 years) from the perspective of participants involved in multidisciplinary collaboration on behalf of children with severe disabilities and their families. The authors employed a multiple-case study approach comprising 26 interviews across six cases. Findings suggest that kindergarten is considered an important partner for families and a major contributor to the provision of services. Kindergartens were valued for their (1) close relationships and intimate knowledge of children as individuals, (2) the sense of security and relief of stress that they provided to paren…
The chains of stress recovery
2021
Ubiquitination primes the cell for recovery from heat stress
Efficient differentiation of embryonic stem cells into mesodermal precursors by BMP, retinoic acid and Notch signalling
2012
The ability to direct differentiation of mouse embryonic stem (ES) cells into specific lineages not only provides new insights into the pathways that regulate lineage selection but also has translational applications, for example in drug discovery. We set out to develop a method of differentiating ES cells into mesodermal cells at high efficiency without first having to induce embryoid body formation. ES cells were plated on a feeder layer of PA6 cells, which have membrane-associated stromal-derived inducing activity (SDIA), the molecular basis of which is currently unknown. Stimulation of ES/PA6 co-cultures with Bone Morphogenetic Protein 4 (BMP4) both favoured self-renewal of ES cells and…
Feeding, cooking, sharing : a brief social history of food
2020
This work addresses the food system as a complex structure connected to the environment, like a living organism. It uses the contributions from multiple fields (including anthropology, nutritional, medicine, and economics) to establish connections between analytically disparate fields in order to highlight their transformations over time and space. It also studies social organisation over millions of years to understand the synergy between the environment, extraction technologies, economic and political structures, and the resulting cooking environments (each with their own social construction of tastes) as conditioning factors for sickness and death. In short, it delves into the anthropolo…
High gain/bandwidth off-chip antenna loaded with metamaterial unit-cell impedance matching circuit for sub-terahertz near-field electronic systems
2022
An innovative of-chip antenna (OCA) is presented that exhibits high gain and efciency performance at the terahertz (THz) band and has a wide operational bandwidth. The proposed OCA is implemented on stacked silicon layers and consists of an open circuit meandering line. It is shown that by loading the antenna with an array of subwavelength circular dielectric slots and terminating it with a metamaterial unit cell, its impedance bandwidth is enhanced by a factor of two and its gain on average by about 4 dB. Unlike conventional antennas, where the energy is dissipated in a resistive load, the technique proposed here signifcantly reduces losses. The antenna is excited from underneath the anten…
How connected are the major forms of irrationality? : an analysis of pseudoscience, science denial, fact resistance and alternative facts
2017
Science is a fact-finding practice, but there are many other fact-finding practices that apply largely the same patterns of reasoning in order to achieve as reliable information as possible in empirical issues. The fact-finding practices form in their turn a subcategory of rational discourse, a wider category that also encompasses argumentation on non-empirical issues. Based on these categories, it is easy to see the relationship between on the one hand pseudoscience, on the other hand fact resistance, disinformation, and fallacies of reasoning. The flaws in argumentation are similar, and the main difference is whether or not the subject matter falls within or without the realm of science.
Synthesis, structure and reaction chemistry of a nucleophilic aluminyl anion.
2018
The reactivity of aluminium compounds is dominated by their electron deficiency and consequent electrophilicity; these compounds are archetypal Lewis acids (electron-pair acceptors). The main industrial roles of aluminium, and classical methods of synthesizing aluminium–element bonds (for example, hydroalumination and metathesis), draw on the electron deficiency of species of the type AlR3 and AlCl31,2. Whereas aluminates, [AlR4]−, are well known, the idea of reversing polarity and using an aluminium reagent as the nucleophilic partner in bond-forming substitution reactions is unprecedented, owing to the fact that low-valent aluminium anions analogous to nitrogen-, carbon- and boron-centred…