Multicomponent low molecular weight gelators

Low molecular weight gelators (LMWG) self-assemble in solution into one-dimensional objects such as fibres or tapes. The entanglement of these fibres or tapes results in the formation of a network and a gel. In general, LMWG are investigated as single component systems. However, there are significant potential opportunities from mixed LMWG systems, which are rarely investigated. Here, we discuss the potential of multicomponent systems, and critically discuss the challenges

The Toeplitz algebra of a Hilbert bimodule

Suppose a C*-algebra A acts by adjointable operators on a Hilbert A-module X. Pimsner constructed a C*-algebra O_X which includes, for particular choices of X, crossed products of A by Z, the Cuntz algebras O_n, and the Cuntz-Krieger algebras O_B. Here we analyse the representations of the corresponding Toeplitz algebra. One consequence is a uniqueness theorem for the Toeplitz-Cuntz-Krieger algebras of directed graphs, which includes Cuntz's uniqueness theorem for O_\infty.Comment: AMS-LaTeX, 22 pages; originally posted an old version by mistak

Maximal violation of Bell inequalities by position measurements

We show that it is possible to find maximal violations of the CHSH-Bell inequality using only position measurements on a pair of entangled non-relativistic free particles. The device settings required in the CHSH inequality are done by choosing one of two times at which position is measured. For different assignments of the "+" outcome to positions, namely to an interval, to a half line, or to a periodic set, we determine violations of the inequalities, and states where they are attained. These results have consequences for the hidden variable theories of Bohm and Nelson, in which the two-time correlations between distant particle trajectories have a joint distribution, and hence cannot violate any Bell inequality.Comment: 13 pages, 4 figure

Active management in Serious Genetic Disorders

Twenty years ago we were taught to classify the cause of any medical condition into those that were 'genetic' and those that were 'acquired'.  Subsequently the acquired group could be subdivided according to aetiology. Either directly or by implication we were told that genetic disorders were untreatable and that they were always rare, making up an insignificant proportion of medical practice. This article gives a personal view of the field of medical genetics and is based on two established facts, firstly that genetic diseases are now so frequent that every doctor should be conversant with basic genetic principles. Secondly many genetic conditions if not amenable to curative treatment, are at least responsive to careful management which can prolong and increase the quality of life. At this stage we should emphasise one other aspect, which concerns the philosophy behind genetic counselling. Such counselling is not just the calculation of empiric or theoretical risks that a disease will recur, followed by telling the family and then leaving them to come to terms with unpleasant probabilities. In genetic counselling the range of options open to different members of a family can be fully explained in the light of their risks. At the same time counselling of a wider nature can be offered providing emotional support to many members of the family. By allowing individuals within a family to come to terms with the emotional aspects of an inherited condition, counselling, not necessarily provided by a genetic counsellor alone can be actively therapeutic. Let us now select some severe disorders with a major genetic component and examine the therapeutic approaches available

Strong Shift Equivalence of C∗C^*-correspondences

We define a notion of strong shift equivalence for $C^*$-correspondences and show that strong shift equivalent $C^*$-correspondences have strongly Morita equivalent Cuntz-Pimsner algebras. Our analysis extends the fact that strong shift equivalent square matrices with non-negative integer entries give stably isomorphic Cuntz-Krieger algebras.Comment: 26 pages. Final version to appear in Israel Journal of Mathematic

NS Fivebrane and Tachyon Condensation

We argue that a semi-infinite D6-brane ending on an NS5-brane can be obtained from the condensation of the tachyon on the unstable D9-brane of type IIA theory. The construction uses a combination of the descriptions of these branes as solitons of the worldvolume theory of the D9-brane. The NS5-brane, in particular, involves a gauge bundle which is operator valued, and hence is better thought of as a gerbe.Comment: 20 pages, harvma

The Status of Antibiotics

From a dissertation read before the Royal Medical Society on Friday, 1st November, 1963.Many attribute the earliest recognition of an antibiotic effect to Sir Alexander Fleming. However, in 1877, 50 years before Fleming’s discovery, Pasteur and Joubert described the phenomenon of bacterial antagonism; the process whereby the growth of certain species is inhibited in the presence of others. In the particular case of the anthrax bacillus they found that growth was inhibited in cultures contaminated with ‘common bacteria’ (those types now known as the Enterobacteriaciae). Shortly afterwards the term “antibiosis” was introduced for such antagonism

Gut dysfunction in patients with multiple sclerosis and the role of spinal cord involvement in the disease.

Bowel and bladder symptoms are highly prevalent in patients with multiple sclerosis (MS). Bladder dysfunction (affecting 75% of these patients) is caused by disease in the spinal cord, whilst the pathophysiology of bowel dysfunction is unknown. Pathways regulating both the organs lie in close proximity to the spinal cord, and coexistence of their dysfunction might be the result of a common pathophysiology. If so, the prevalence of bladder symptoms should be greater in patients with MS and bowel symptoms. This hypothesis is tested in the study. We also evaluated how patient-reported symptoms quantify bowel dysfunction

Electrochemically-triggered spatially and temporally resolved multi-component gels

Spatial control over gelation with low molecular weight gelators is possible using an electrochemically-driven pH triggering method. Gelation occurs at the electrode surface. We show here that composition control in multi-component low molecular weight hydrogels can also be achieved, allowing simultaneous spatial, temporal and compositional control

Morpholino Oligonucleotide Cross-Linked Hydrogels as Portable Optical Oligonucleotide Biosensors

© 2018 American Chemical Society. Morpholino Oligonucleotides (MOs), an uncharged DNA analogue, are functionalized with an acrylamide moiety and incorporated into polymer hydrogels as responsive cross-links for microRNA sequence detection. The MO cross-links can be selectively cleaved by a short target analyte single-stranded DNA (ssDNA) sequence based on microRNA, inducing a distinct swelling response measured optically. The MO cross-links offer significant improvement over DNA based systems through improved thermal stability, no salt requirement and 1000-fold improved sensitivity over a comparative biosensor, facilitating a wider range of sensing conditions. Analysis was also achieved using a mobile phone camera, demonstrating portability