The Mod-2 Cohomology Ring of the Third Conway Group is Cohen-Macaulay

By explicit machine computation we obtain the mod-2 cohomology ring of the third Conway group Co_3. It is Cohen-Macaulay, has dimension 4, and is detected on the maximal elementary abelian 2-subgroups.Comment: 12 pages; writing style now more concis

Representations and KK-theory of Discrete Groups

Let $\Gamma$ be a discrete group of finite virtual cohomological dimension with certain finiteness conditions of the type satisfied by arithmetic groups. We define a representation ring for $\Gamma$, determined on its elements of finite order, which is of finite type. Then we determine the contribution of this ring to the topological $K$-theory $K^*(B\Gamma)$, obtaining an exact formula for the difference in terms of the cohomology of the centralizers of elements of finite order in $\Gamma$.Comment: 4 page

Nonlinearities and Parametric Amplification in Superconducting Coplanar Waveguide Resonators

Experimental investigations of the nonlinear properties of superconducting niobium coplanar waveguide resonators are reported. The nonlinearity due to a current dependent kinetic inductance of the center conductor is strong enough to realize bifurcation of the nonlinear oscillator. When driven with two frequencies near the threshold for bifurcation, parametric amplification with a gain of +22.4 dB is observed.Comment: 4 pages, 5 figures, 1 table. In version 2: Added appendix with model description and fits to measurements. Minor corrections and rephrasin

Ferroelectric displacements in multiferroic Y(Mn,Ga)O-3

We have studied the effects of substitution of Mn3+ by Ga3+ on the crystal structure of YMnO3. Y(Mn,Ga)O-3 is a magnetoferroelectric in which the ferroelectric displacements from the YO7 polyhedra are associated with buckling and tilting of the MnO5 bipyramids. The differences in ionic radius and orbital occupation between Mn3+ and Ga3+ result in an increase of the c/a lattice parameter ratio. This dilation is not associated with the displacements of MnO5 bipyramids, but with the elongation of the YO6 antiprisms. The magnitude of the local YO6 dipoles decrease with Ga substitution

An efficient approach for solving nonlinear troesch's and bratu's problems by wavelet analysis method

We introduce Chebyshev wavelet analysis method to solve the nonlinear Troesch and Bratu problems. Chebyshev wavelets expansions together with operational matrix of derivative are employed to reduce the computation of nonlinear problems to a system of algebraic equations. Several examples are given to validate the efficiency and accuracy of the proposed technique. We compare the results with those ones reported in the literature in order to demonstrate that the method converges rapidly and approximates the exact solution very accurately by using only a small number of Chebyshev wavelet basis functions. Convergence analysis is also included

Australian community pharmacy services: a survey of what people with chronic conditions and their carers use versus what they consider important

Objective To explore the purpose/s for which people with chronic conditions and their carers use Australian community pharmacies, and compare this to what pharmacy services they consider important, from the perspectives of both consumers and pharmacists. Design An exploratory study involving a survey, which asked participants to indicate the pharmacy services they had ever used, and rate the importance of 22 pharmacy services to them, or the person they care for, or for their consumers if a pharmacist. Setting Four regions of Australia: Logan-Beaudesert and Mt Isa/North West region, Queensland, Northern Rivers, New South Wales, and the Greater Perth area, Western Australia. Participants Surveys were undertaken with 602 consumers and 91 community pharmacists. Results Community pharmacy is predominantly used to obtain advice about medication and whether a doctor's visit is necessary, as well as for monitoring and screening services. Pharmacy services that were patient centric were important, such as individualised medication advice and respectful care, as well as tools or procedures to facilitate streamlined medication access. Less important services included adult vaccinations and health and wellness programmes. Carers identified services that assisted them with their specific role/s to be important. Overall, community pharmacists had a good understanding of the services that were important to people with chronic conditions and their carers. Conclusions People with chronic conditions and their carers not only care about what services are delivered, but how they are delivered; they sought services that generally improved their access to medication and information, but in a way that was patient centred. Ultimately, pharmacists understood the importance of patient-centred care for people with chronic conditions and their carers, perhaps indicating a greater acceptance of integrating patient-centred care into their everyday practice

The impact of phenotype, ethnicity and genotype on progression of Type 2 diabetes mellitus

Aim: To conduct a comprehensive review of studies of glycaemic deterioration in type 2 diabetes and identify the major factors influencing progression.Methods: We conducted a systematic literature search with terms linked to type 2 diabetes progression. All the included studies were summarized based upon the factors associated with diabetes progression and how the diabetes progression was defined.Results: Our search yielded 2785 articles; based on title, abstract and full‐text review, we included 61 studies in the review. We identified seven criteria for diabetes progression: ‘Initiation of insulin’, ‘Initiation of oral antidiabetic drug’, ‘treatment intensification’, ‘antidiabetic therapy failure’, ‘glycaemic deterioration’, ‘decline in beta‐cell function’ and ‘change in insulin dose’. The determinants of diabetes progression were grouped into phenotypic, ethnicity and genotypic factors. Younger age, poorer glycaemia and higher body mass index at diabetes diagnosis were the main phenotypic factors associated with rapid progression. The effect of genotypic factors on progression was assessed using polygenic risk scores (PRS); a PRS constructed from the genetic variants linked to insulin resistance was associated with rapid glycaemic deterioration. The evidence of impact of ethnicity on progression was inconclusive due to the small number of multi‐ethnic studies.Conclusion: We have identified the major determinants of diabetes progression—younger age, higher BMI, higher HbA1c and genetic insulin resistance. The impact of ethnicity is uncertain; there is a clear need for more large‐scale studies of diabetes progression in different ethnic groups

Magnetodielectric and magnetoelastic coupling in TbFe3(BO3)4

We have studied the magnetodielectric and magnetoelastic coupling in TbFe3(BO3)4 single crystals by means of capacitance, magnetostriction and Raman spectroscopy measurements. The data reveal strong magnetic field effects on the dielectric constant and on the macroscopic sample length which are associated to long range magnetic ordering and a field-driven metamagnetic transition. We discuss the coupling of the dielectric, structural, and magnetic order parameters and attribute the origin of the magnetodielectric coupling to phonon mode shifts according to the Lyddane-Sachs-Teller (LST) relation.Comment: Accepted for publication in Physical Review

Extending structures I: the level of groups

Let $H$ be a group and $E$ a set such that $H \subseteq E$. We shall describe and classify up to an isomorphism of groups that stabilizes $H$ the set of all group structures that can be defined on $E$ such that $H$ is a subgroup of $E$. A general product, which we call the unified product, is constructed such that both the crossed product and the bicrossed product of two groups are special cases of it. It is associated to $H$ and to a system $\bigl((S, 1_S,\ast), \triangleleft, \, \triangleright, \, f \bigl)$ called a group extending structure and we denote it by $H \ltimes S$. There exists a group structure on $E$ containing $H$ as a subgroup if and only if there exists an isomorphism of groups $(E, \cdot) \cong H \ltimes S$, for some group extending structure $\bigl((S, 1_S,\ast), \triangleleft, \, \triangleright, \, f \bigl)$. All such group structures on $E$ are classified up to an isomorphism of groups that stabilizes $H$ by a cohomological type set ${\mathcal K}^{2}_{\ltimes} (H, (S, 1_S))$. A Schreier type theorem is proved and an explicit example is given: it classifies up to an isomorphism that stabilizes $H$ all groups that contain $H$ as a subgroup of index 2.Comment: 17 pages; to appear in Algebras and Representation Theor