Biological basis for cerebral dysfunction in schizophrenia in contrast with Alzheimer’s disease

Schizophrenia and Alzheimer’s disease are two disorders that, while conceptualized as pathophysiologically and clinically distinct, cause substantial cognitive and behavioral impairment worldwide, and target apparently similar – or nearby – circuitry in regions such as the temporal and frontal lobes.We review the salient differences and similarities from selected historical, nosological, and putative mechanistic viewpoints, as a means to help both clinicians and researchers gain a better insight into these intriguing disorders, for which over a century of research and decades of translational development was needed to begin yielding treatments that are objectively effective, but still very far from entirely satisfactory. Ongoing comparison and “cross-pollination” among these approaches to disorders that produce similar deficits is likely to continue improving both our insight into the mechanisms at play, and the development of biotechnological approaches to tackle both conditions – and related disorders – more rapidly and efficaciously

Weight teasing and eating disorders. A comparative study in adolecent and adult samples

Disordered eating, unhealthy weight-control behaviours and body dissatisfaction are associated with diminished mental health. A key aspect that has been identified for the development of disordered eating behaviours and body dissatisfaction is to be teased. Additionally, the literature suggests that weight may affect the relationship between weight-teasing and disordered eating and body dissatisfaction, although this pattern is unclear. This study presents two cross-sectional studies with an adult and an adolescent sample. The adolescent sample comprised 15,224 participants, and the adult sample comprised 321 participants, all from Spain. Hierarchical regression analyses were conducted. Aims: to assess the relations among disordered eating, body dissatisfaction, weight, and weight-teasing among adolescents and adults; and to examine whether weight-teasing, weight, age, and gender predict disordered eating and body dissatisfaction in adults and adolescents. The results showed that adolescent girls presented greater effects, and all interactions were significant between weight-teasing and eating disorders. Adults also showed greater effects for women, and only eating disorder interactions were significant. Weight-control behaviours did not show any relationship with weight-teasing. Conclusion: Different approaches may be used in the prevention of eating disorders. Our results show that weight-teasing affects adults differently from adolescents

Spectra of weighted rooted graphs having prescribed subgraphs at some levels

Let B be a weighted generalized Bethe tree of k levels (k > 1) in which nj is the number of vertices at the level k-j+1 (1 ≤ j ≤ k). Let Δ \subset {1, 2,., k-1} and F={Gj:j \in Δ}, where Gj is a prescribed weighted graph on each set of children of B at the level k-j+1. In this paper, the eigenvalues of a block symmetric tridiagonal matrix of order n1+n2 +...+nk are characterized as the eigenvalues of symmetric tridiagonal matrices of order j, 1≤j≤k, easily constructed from the degrees of the vertices, the weights of the edges, and the eigenvalues of the matrices associated to the family of graphs F. These results are applied to characterize the eigenvalues of the Laplacian matrix, including their multiplicities, of the graph β(F) obtained from β and all the graphs in F={Gj:j \in Δ}; and also of the signless Laplacian and adjacency matrices whenever the graphs of the family F are regular.CIDMAFCTFEDER/POCI 2010PTDC/MAT/112276/2009Fondecyt - IC Project 11090211Fondecyt Regular 110007

Compact, low power and low threshold electrically pumped micro disc lasers for 20Gb/s non return to zero all optical wavelength conversion

\u3cp\u3eUsing a 7.5μm wide InP Micro-Disc-Laser, with a very low ∼100μA threshold current, heterogeneously integrated on top of Silicon on Insulator substrate, all optical NRZ wavelength conversion at speeds up to 20Gb/s is demonstrated.\u3c/p\u3

Superconductivity as a Bose-Einstein condensation?

Bose-Einstein condensation (BEC) in two dimensions (2D) (e.g., to describe the quasi-2D cuprates) is suggested as the possible mechanism widely believed to underlie superconductivity in general. A crucial role is played by nonzero center-of-mass momentum Cooper pairs (CPs) usually neglected in BCS theory. Also vital is the unique {\it linear} dispersion relation appropriate to weakly-coupled "bosonic" CPs moving in the Fermi sea--rather than in vacuum where the dispersion would be quadratic but only for very strong coupling, and for which BEC is known to be impossible in 2D.Comment: 6 pages included 3 figure

New conditions for the additive inverse eigenvalue problem for matrices

AbstractThis paper deals with the following inverse eigenvalue problem: Given an n by n real symmetric matrix A and a set of real numbers {λi}1n, find a diagonal matrix D such that A + D has eigenvalues λi. For the solvability of this problem a number of necessary conditions and sufficient conditions are known. In this work, new necessary conditions are derived, while some sufficient conditions are optimized. In particular, one sufficient condition due to Morel is obtained by optimizing a sufficient condition discovered by Laborde

Cooper pair dispersion relation in two dimensions

The Cooper pair binding energy {\it vs.} center-of-mass-momentum dispersion relation for Bose-Einstein condensation studies of superconductivity is found in two dimensions for a renormalized attractive delta interaction. It crosses over smoothly from a linear to a quadratic form as coupling varies from weak to strong.Comment: 2 pages, 1 figure, new version published in Physica

Vaginal Natural Orifice Transluminal Endoscopic Surgery for Gynecologic and Gynecologic Oncology Procedures

Vaginal Natural Orifice Transluminal Endoscopic Surgery (vNOTES) is an exciting new procedure that combines the best of laparoscopic and transvaginal surgery. The skills of a laparoscopic surgeon are applied to this approach which offers several advantages over traditional laparoscopy. First, the recovery of a vaginal procedure is shorter and less painful. Second, there is no abdominal incision which avoids potential for wound infection, herniation, pain and unsightly scarring. Third, the surgeon is seated with more comfortable ergonomics than traditional laparoscopy. Fourth, the blood supply is controlled very early in the procedure reducing overall blood loss. Fifth, the specimen for removal is quite close to the operator which enables less crossing of instruments and allows larger scopes with better illumination to be used. Finally, where traditional laparoscopy progresses to a smaller and smaller surgical area as the operation proceeds deeper into the pelvis, vNOTES is continually moving out of the pelvis with greater room for specimen manipulation and visualization. Advantages over traditional transvaginal surgery include the ability to examine the entire abdomen, the safety of direct visualization of the pedicles for adnexal removal, and the ability to perform abdominal procedures including lymph node removal, omentectomy, appendectomy, and biopsies not previously available to the vaginal approach

Bose-Einstein condensation of nonzero-center-of-mass-momentum Cooper pairs

Cooper pair (CP) binding with both zero and nonzero center-of-mass momenta (CMM) is studied with a set of renormalized equations assuming a short-ranged (attractive) pairwise interfermion interaction. Expanding the associated dispersion relation in 2D in powers of the CMM, in weak-to-moderate coupling a term {\it linear} in the CMM dominates the pair excitation energy, while the quadratic behavior usually assumed in Bose-Einstein (BE)-condensation studies prevails for any coupling {\it only} in the limit of zero Fermi velocity when the Fermi sea disappears, i.e., in vacuum. In 3D this same behavior is observed numerically. The linear term, moreover, exhibits CP breakup beyond a threshold CMM value which vanishes with coupling. This makes all the excited (nonzero-CMM) BE levels with preformed CPs collapse into a single ground level so that a BCS condensate (where only zero CMM CPs are usually allowed) appears in zero coupling to be a special case in either 2D or 3D of the BE condensate of linear-dispersion-relation CPs.Comment: Four pages including four figures. To be published in Physica

Kinetics of active surface-mediated diffusion in spherically symmetric domains

We present an exact calculation of the mean first-passage time to a target on the surface of a 2D or 3D spherical domain, for a molecule alternating phases of surface diffusion on the domain boundary and phases of bulk diffusion. We generalize the results of [J. Stat. Phys. {\bf 142}, 657 (2011)] and consider a biased diffusion in a general annulus with an arbitrary number of regularly spaced targets on a partially reflecting surface. The presented approach is based on an integral equation which can be solved analytically. Numerically validated approximation schemes, which provide more tractable expressions of the mean first-passage time are also proposed. In the framework of this minimal model of surface-mediated reactions, we show analytically that the mean reaction time can be minimized as a function of the desorption rate from the surface.Comment: Published online in J. Stat. Phy