The isomorphism conjecture for 3-manifold groups and K-theory of virtually poly-surface groups

This article has two purposes. In \cite{R3} (math.KT/0405211) we showed that the FIC (Fibered Isomorphism Conjecture for pseudoisotopy functor) for a particular class of 3-manifolds (we denoted this class by \cal C) is the key to prove the FIC for 3-manifold groups in general. And we proved the FIC for the fundamental groups of members of a subclass of \cal C. This result was obtained by showing that the double of any member of this subclass is either Seifert fibered or supports a nonpositively curved metric. In this article we prove that for any M in {\cal C} there is a closed 3-manifold P such that either P is Seifert fibered or is a nonpositively curved 3-manifold and \pi_1(M) is a subgroup of \pi_1(P). As a consequence this proves that the FIC is true for any B-group (see definition 3.2 in \cite{R3}). Therefore, the FIC is true for any Haken 3-manifold group and hence for any 3-manifold group (using the reduction theorem of \cite{R3}) provided we assume the Geometrization conjecture. The above result also proves the FIC for a class of 4-manifold groups (see \cite{R2}(math.GT/0209119)). The second aspect of this article is to relax a condition in the definition of strongly poly-surface group (\cite{R1} (math.GT/0209118)) and define a new class of groups (we call them {\it weak strongly poly-surface} groups). Then using the above result we prove the FIC for any virtually weak strongly poly-surface group. We also give a corrected proof of the main lemma of \cite{R1}.Comment: 12 pages, AMS Latex file, 1 figure, final version. accepted for publication in K-theor

Attitudes Toward Testicular Cancer and Self-Examination Among Northern Irish Males

Testicular cancer incidence rates are increasing worldwide making it the most common malignancy in males aged 15 to 45 years. Without a known way to prevent the disease health professionals must promote awareness and early detection. A literature review identified a scarcity of information regarding awareness and knowledge of, and attitudes toward, testicular cancer and testicular self-examination among men in Northern Ireland. This study aimed to establish baseline data for Northern Ireland using a convenience sample of 150 men, aged 18 to 45 years. The sample was recruited from across the country and so represents a range of education and area deprivation levels. An online survey was used to collect data. Results showed that while 39% of respondents correctly identified the age group at highest risk for testicular cancer, only 17% of respondents had ever heard of a testicular self-examination. Analysis revealed knowledge, awareness, and attitudes differed by age groups and area deprivation quintiles. It is recommended that health promoters in Northern Ireland and elsewhere use these findings to tailor health promotion initiatives to engage men and raise testicular cancer and self-examination awareness. </jats:p

Universal manifold pairings and positivity

Gluing two manifolds M_1 and M_2 with a common boundary S yields a closed manifold M. Extending to formal linear combinations x=Sum_i(a_i M_i) yields a sesquilinear pairing p= with values in (formal linear combinations of) closed manifolds. Topological quantum field theory (TQFT) represents this universal pairing p onto a finite dimensional quotient pairing q with values in C which in physically motivated cases is positive definite. To see if such a "unitary" TQFT can potentially detect any nontrivial x, we ask if is non-zero whenever x is non-zero. If this is the case, we call the pairing p positive. The question arises for each dimension d=0,1,2,.... We find p(d) positive for d=0,1, and 2 and not positive for d=4. We conjecture that p(3) is also positive. Similar questions may be phrased for (manifold, submanifold) pairs and manifolds with other additional structure. The results in dimension 4 imply that unitary TQFTs cannot distinguish homotopy equivalent simply connected 4-manifolds, nor can they distinguish smoothly s-cobordant 4-manifolds. This may illuminate the difficulties that have been met by several authors in their attempts to formulate unitary TQFTs for d=3+1. There is a further physical implication of this paper. Whereas 3-dimensional Chern-Simons theory appears to be well-encoded within 2-dimensional quantum physics, eg in the fractional quantum Hall effect, Donaldson-Seiberg-Witten theory cannot be captured by a 3-dimensional quantum system. The positivity of the physical Hilbert spaces means they cannot see null vectors of the universal pairing; such vectors must map to zero.Comment: Published by Geometry and Topology at http://www.maths.warwick.ac.uk/gt/GTVol9/paper53.abs.htm

Wallerian-like axonal degeneration in the optic nerve after excitotoxic retinal insult: an ultrastructural study

BACKGROUND: Excitotoxicity is involved in the pathogenesis of a number neurodegenerative diseases, and axonopathy is an early feature in several of these disorders. In models of excitotoxicity-associated neurological disease, an excitotoxin delivered to the central nervous system (CNS), could trigger neuronal death not only in the somatodendritic region, but also in the axonal region, via oligodendrocyte N-methyl-D-aspartate (NMDA) receptors. The retina and optic nerve, as approachable regions of the brain, provide a unique anatomical substrate to investigate the “downstream” effect of isolated excitotoxic perikaryal injury on central nervous system (CNS) axons, potentially providing information about the pathogenesis of the axonopathy in clinical neurological disorders. Herein, we provide ultrastructural information about the retinal ganglion cell (RGC) somata and their axons, both unmyelinated and myelinated, after NMDA-induced retinal injury. Male Sprague-Dawley rats were killed at 0 h, 24 h, 72 h and 7 days after injecting 20 nM NMDA into the vitreous chamber of the left eye (n = 8 in each group). Saline-injected right eyes served as controls. After perfusion fixation, dissection, resin-embedding and staining, ultrathin sections of eyes and proximal (intraorbital) and distal (intracranial) optic nerve segments were evaluated by transmission electron tomography (TEM). RESULTS: TEM demonstrated features of necrosis in RGCs: mitochondrial and endoplasmic reticulum swelling, disintegration of polyribosomes, rupture of membranous organelle and formation of myelin bodies. Ultrastructural damage in the optic nerve mimicked the changes of Wallerian degeneration; early nodal/paranodal disturbances were followed by the appearance of three major morphological variants: dark degeneration, watery degeneration and demyelination. CONCLUSION: NMDA-induced excitotoxic retinal injury causes mainly necrotic RGC somal death with Wallerian-like degeneration of the optic nerve. Since axonal degeneration associated with perikaryal excitotoxic injury is an active, regulated process, it may be amenable to therapeutic intervention.Sarabjit K. Saggu, Hiren P. Chotaliya, Peter C. Blumbergs and Robert J. Casso

Nexus researching church toddler groups

The Headlines This unique research project revealed fascinating insights into the spiritual flourishing of very young children and how this is nourished within church toddler groups in England. The findings have uncovered evidence of very young children exploring self-understanding and the nurturing of relationships with others. We found that church toddler groups contribute to children’s spiritual flourishing through: • Providing an environment that fosters a non-threatening connection with spirituality and faith. • Nurturing and sustaining relationships with families. • Offering a safe place for young families to come together, play together, and feel supported in their spiritual well-being. • Enabling a sense of belonging to the church community through engagement in the church toddler group. However, we also found that: • There is a need for adults to have a deeper awareness of the significant role they play in enabling the spiritual flourishing of very young children. • A common misunderstanding of spiritual nurture in terms of faith development hampers focused attention on the spiritual nurture of very young children

Severe pneumonia due to Parachlamydia acanthamoebae following intranasal inoculation: a mice model.

Parachlamydia acanthamoebae is an obligate intracellular bacterium naturally infecting free-living amoebae. The role of this bacterium as an agent of pneumonia is suggested by sero-epidemiological studies and molecular surveys. Furthermore, P. acanthamoebae may escape macrophages microbicidal effectors. Recently, we demonstrated that intratracheal inoculation of P. acanthamoebae induced pneumonia in 100% of infected mice. However, the intratracheal route of infection is not the natural way of infection and we therefore developed an intranasal murine model. Mice inoculated with P. acanthamoebae by intranasal inoculation lost 18% of their weight up to 8 days post-inoculation. All mice presented histological signs of pneumonia at day 2, 4, 7, and 10 post-inoculation, whereas no control mice harboured signs of pneumonia. A 5-fold increase in bacterial load was observed from day 0 to day 4 post-inoculation. Lungs of inoculated mice were positive by Parachlamydia-specific immunohistochemistry 4 days post-inoculation, and P. acanthamoebae were localized within macrophages. Thus, we demonstrated that P. acanthamoebae induce a severe pneumonia in mice. This animal model (i) further supports the role of P. acanthamoebae as an agent of pneumonia, confirming the third Koch postulate, and (ii) identified alveolar macrophages as one of the initial cells where P. acanthamoebae is localized following infection