Artificial Intelligence (AI) and robotics are likely to have a significant long-term impact on higher education (HE). The scope of this impact is hard to grasp partly because the literature is ...siloed, as well as the changing meaning of the concepts themselves. But developments are surrounded by controversies in terms of what is technically possible, what is practical to implement and what is desirable, pedagogically or for the good of society. Design fictions that vividly imagine future scenarios of AI or robotics in use offer a means both to explain and query the technological possibilities. The paper describes the use of a wide-ranging narrative literature review to develop eight such design fictions that capture the range of potential use of AI and robots in learning, administration and research. They prompt wider discussion by instantiating such issues as how they might enable teaching of high order skills or change staff roles, as well as exploring the impact on human agency and the nature of datafication.
Recent advances in omics technologies have led to unprecedented efforts characterizing the molecular changes that underlie the development and progression of a wide array of complex human diseases, ...including cancer. As a result, multi-omics analyses-which take advantage of these technologies in genomics, transcriptomics, epigenomics, proteomics, metabolomics, and other omics areas-have been proposed and heralded as the key to advancing precision medicine in the clinic. In the field of precision oncology, genomics approaches, and, more recently, other omics analyses have helped reveal several key mechanisms in cancer development, treatment resistance, and recurrence risk, and several of these findings have been implemented in clinical oncology to help guide treatment decisions. However, truly integrated multi-omics analyses have not been applied widely, preventing further advances in precision medicine. Additional efforts are needed to develop the analytical infrastructure necessary to generate, analyze, and annotate multi-omics data effectively to inform precision medicine-based decision-making.
Vector vortex beams are structured states of light that are nonseparable in their polarisation and spatial mode, they are eigenmodes of free-space and many fiber systems, and have the capacity to be ...used as information carriers for both classical and quantum communication. Here, we outline recent progress in our understanding of these modes, from their creation to their characterization and detection. We then use these tools to study their propagation behavior in free-space and optical fiber and show that modal cross-talk results in a decay of vector states into separable scalar modes, with a concomitant loss of information. We present a comparison between probabilistic and deterministic detection schemes showing that the former, while ubiquitous, negates the very benefit of increased dimensionality in quantum communication while reducing signal in classical communication links. This work provides a useful introduction to the field as well as presenting new findings and perspectives to advance it further.
pH–rate profiles for aqueous–organic protodeboronation of 18 boronic acids, many widely viewed as unstable, have been studied by NMR and DFT. Rates were pH-dependent, and varied substantially between ...the boronic acids, with rate maxima that varied over 6 orders of magnitude. A mechanistic model containing five general pathways (k 1–k 5) has been developed, and together with input of Btot, K W, K a, and K aH, the protodeboronation kinetics can be correlated as a function of pH (1–13) for all 18 species. Cyclopropyl and vinyl boronic acids undergo very slow protodeboronation, as do 3- and 4-pyridyl boronic acids (t 0.5 > 1 week, pH 12, 70 °C). In contrast, 2-pyridyl and 5-thiazolyl boronic acids undergo rapid protodeboronation (t 0.5 ≈ 25–50 s, pH 7, 70 °C), via fragmentation of zwitterionic intermediates. Lewis acid additives (e.g., Cu, Zn salts) can attenuate (2-pyridyl) or accelerate (5-thiazolyl and 5-pyrazolyl) fragmentation. Two additional processes compete when the boronic acid and the boronate are present in sufficient proportions (pH = pK a ± 1.6): (i) self-/autocatalysis and (ii) sequential disproportionations of boronic acid to borinic acid and borane.
Assembly of the Mycobacterial Cell Wall Jankute, Monika; Cox, Jonathan A.G; Harrison, James ...
Annual review of microbiology,
10/2015, Letnik:
69, Številka:
1
Journal Article
Recenzirano
Mycobacterium tuberculosis
remains one of the most successful bacterial pathogens, claiming over 1.3 million lives worldwide in 2013. The emergence of multidrug-resistant and extensively ...drug-resistant isolates has prompted the need for new drugs and drug targets.
M. tuberculosis
possesses an unusual cell wall dominated by lipids and carbohydrates that provides a permeability barrier against hydrophilic drugs and is crucial for its survival and virulence. This large macromolecular structure, termed the mycolyl-arabinogalactan-peptidoglycan complex, and the phosphatidyl-
myo
-inositol-based lipoglycans are key features of the mycobacterial cell wall. Assembly of these cell wall components is an attractive target for the development of chemotherapeutics against tuberculosis. Herein, we focus on recent biochemical and molecular insights into these complex molecules of
M. tuberculosis
cell wall.
Coffee is one of the most commonly consumed beverages in the world. Its health benefits including improved overall survival have been demonstrated in a variety of disease states. To examine the ...association of coffee consumption with liver disease, a systematic review of studies on the effects of coffee on liver associated laboratory tests, viral hepatitis, nonalcoholic fatty liver disease (NAFLD), cirrhosis and hepatocellular carcinoma (HCC) was performed. Coffee consumption was associated with improved serum gamma glutamyltransferase, aspartate aminotransferase and alanine aminotransferase values in a dose dependent manner in individuals at risk for liver disease. In chronic liver disease patients who consume coffee, a decreased risk of progression to cirrhosis, a lowered mortality rate in cirrhosis patients, and a lowered rate of HCC development were observed. In chronic hepatitis C patients, coffee was associated with improved virologic responses to antiviral therapy. Moreover, coffee consumption was inversely related to the severity of steatohepatitis in patients with non‐alcoholic fatty liver disease. Therefore, in patients with chronic liver disease, daily coffee consumption should be encouraged.
Pioneering studies by Kuivila, published more than 50 years ago, suggested ipso protonation of the boronate as the mechanism for base-catalyzed protodeboronation of arylboronic acids. However, the ...study was limited to UV spectrophotometric analysis under acidic conditions, and the aqueous association constants (K a) were estimated. By means of NMR, stopped-flow IR, and quenched-flow techniques, the kinetics of base-catalyzed protodeboronation of 30 different arylboronic acids has now been determined at pH > 13 in aqueous dioxane at 70 °C. Included in the study are all 20 isomers of C6H n F(5–n)B(OH)2 with half-lives spanning 9 orders of magnitude: <3 ms to 6.5 months. In combination with pH–rate profiles, pK a and ΔS ⧧ values, kinetic isotope effects (2H, 10B, 13C), linear free-energy relationships, and density functional theory calculations, we have identified a mechanistic regime involving unimolecular heterolysis of the boronate competing with concerted ipso protonation/C–B cleavage. The relative Lewis acidities of arylboronic acids do not correlate with their protodeboronation rates, especially when ortho substituents are present. Notably, 3,5-dinitrophenylboronic acid is orders of magnitude more stable than tetra- and pentafluorophenylboronic acids but has a similar pK a.
A
bstract
We study four-dimensional gauge theories with arbitrary simple gauge group with 1-form global center symmetry and 0-form parity or discrete chiral symmetry. We canonically quantize on 𝕋
3
..., in a fixed background field gauging the 1-form symmetry. We show that the mixed 0-form/1-form ’t Hooft anomaly results in a central extension of the global-symmetry operator algebra. We determine this algebra in each case and show that the anomaly implies degeneracies in the spectrum of the Hamiltonian at any finite- size torus. We discuss the consistency of these constraints with both older and recent semiclassical calculations in SU(
N
) theories, with or without adjoint fermions, as well as with their conjectured infrared phases.
An account is presented of the mechanistic aspects of hydrothermal zeolite synthesis. The introduction provides a historical and experimental perspective and is followed by a summary of proposed ...mechanisms and associated modelling studies. The central section of the review contains a description of the most probable mechanistic pathways in zeolite formation. In this, the reaction stages of the induction period, nucleation and crystal growth are examined in chronological sequence. Finally, particular aspects of the synthesis process such as the constitution of growth species, template–framework interactions and the nature of zeolite solubility are treated in more detail.
Emphasis is placed upon the chemical basis of zeolite synthesis. Fundamental to this are the T
O
T bond-making and bond-breaking reactions which establish the equilibration between solid and solution components. The consequent generation of order, driven by energy differences and strongly moderated by kinetic limitations, is essentially one of continuous evolution. However, the discreet step of nucleation provides a discontinuity in which isolated regions of local order are superceded by the establishment of a periodic crystal lattice, capable of propagation. Crystal growth occurs through an in-situ, localised construction process from small, mobile species ordered by the participating cations.
The process of hydrothermal zeolite synthesis can be most adequately explained by a mechanism based upon the solution–mediation model, whether or not there is a visible liquid phase. The common presence of mobile species emphasises the overall similarity of zeolite synthesis reactions so that the need to distinguish any separate “gel rearrangement” or “solid-phase transformation” mechanism becomes unnecessary.
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