Search results for "Retract"

Eigenvectors of k–ψ-contractive wedge operators

AbstractWe present new boundary conditions under which the fixed point index of a strict-ψ-contractive wedge operator is zero. Then we investigate eigenvalues and corresponding eigenvectors of k–ψ-contractive wedge operators.

The existence of FGFR1-5-HT1A receptor heterocomplexes in midbrain 5-HT neurons of the rat: relevance for neuroplasticity.

2012

The ascending midbrain 5-HT neurons to the forebrain may be dysregulated in depression and have a reduced trophic support. Within situproximity ligation assay (PLA) and supported by coimmunoprecipitation and colocation of the FGFR1 and 5-HT1A immunoreactivities in the midbrain raphe cells, evidence for the existence of FGFR1–5-HT1A receptor heterocomplexes in the dorsal and median raphe nuclei of the Sprague Dawley rat as well as in the rat medullary raphe RN33B cells has been obtained. Especially after combined FGF-2 and 8-OH-DPAT treatment, a marked and significant increase in PLA clusters was found in the RN33B cells. Similar results were reached with the FRET technique in HEK293T cells,…

Constructional morphology and mode of attachment of the trunk ofCorynosoma cetaceum (Acanthocephala: Polymorphidae)

1999

Dead specimens of Corynosoma cetaceum were used to describe the trunk musculature of this species and to infer the use of the trunk as a secondary holdfast. Inferences were based on trunk muscle arrangement, changes in trunk shape, size and distribution of spines, and geometry of tegument thickness. The foretrunk of C. cetaceum is swollen and forms a spiny disk that is bent ventrally. The disk is flattened by several groups of muscles not described previously, which seem able to finely adjust the disk surface over the substratum. Disk attachment appears to be accomplished by two dorsal neck retractor muscles specialized in pulling the anchored proboscis into the foretrunk. This mechanism ha…

Comments to the paper "do we really need new medical information about the Turin Shroud?".

2015

Abstract Following the interesting arguments raised in a recent letter to the editor, about a paper recently published in this journal, the authors are happy to take a cue from them to clarify some facts that have not been sufficiently treated for space. After a description of the methods used, arguments regarding a blunt trauma on the right shoulder with consequent dislocation, the position of the hands on the pubis with brachial plexus injury, and the wrist nailing that caused retracted thumbs are discussed in detail.

Ritrattare la metafisica?

2016

L'articolo discute alcune interpretazioni del libro di L. Samonà, Ritrattazioni della metafisica, mettendo in rilievo lo sfondo ontologico della fenomenologia ermeneutica e il carattere dialettico interno alla dimostrazione per via di confutazione del principio inconcusso

Proper $k$-ball-contractive mappings in $C_b^m[0, + infty)$

2021

In this paper we deal with the Banach space C-b(m)[0,+infinity] of all m-times continuously derivable, bounded with all derivatives up to the order m, real functions defined on [0, +infinity). We prove, for any epsilon > 0, the existence of a new proper k-ball-contractive retraction with k < 1+epsilon of the closed unit ball of the space onto its boundary, so that the Wosko constant W-gamma(C-b(m)[0,+infinity]) is equal to 1.

MR2370688 (2009e:46013) Navarro-Pascual, J. C.; Mena-Jurado, J. F.; Sánchez-Lirola, M. G. A two-dimensional inequality and uniformly continuous retra…

2009

Let X be an infinite-dimensional uniformly convex Banach space and let BX and SX be its closed unit ball and unit sphere, respectively. The main result of the paper is that the identity mapping on BX can be expressed as the mean of n uniformly continuous retractions from BX onto SX for every n >= 3. Then, the authors observe that the result holds under a property weaker than uniform convexity, satisfied by any complex Banach space, so that the result generalizes that of [A. Jim´enez-Vargas et al., Studia Math. 135 (1999), no. 1, 75–81; MR1686372 (2000b:46025)]. As an application the extremal structure of spaces of vector-valued uniformly continuous mappings is studied.

On k-ball contractive retractions in F-normed ideal spaces

2010

Let X be an infinite dimensional F-normed space and r a positive number such that the closed ball B_r(X) of radius r is properly contained in X. For a bounded subset A of X, the Hausdorff measure of noncompactness gamma(A) of A is the infimum of all $\eps >0$ such that A has a finite $\eps$-net in X. A retraction R of B_r(X) onto its boundary is called k-ball contractive if $\gamma(RA) \le k \gamma(A)$ for each subset A of B_r(X). The main aim of this talk is to give examples of regular F-normed ideal spaces in which there is a 1-ball contractive retraction or, for any $\eps>0$, a $(1+ \eps)$-ball contractive retraction with positive lower Hausdorff measure of noncompactness.

A NEW KIND OF DISPOSABLE AUTOSTATIC SURGICAL RETRACTOR IN INGUINAL HERNIA REPAIR

2009

Objectives: The aim of this study is to demonstrate the effectiveness of a new kind of disposable autostatic surgical retractor in hernias procedures in order to achieve an easier, faster, and safer surgical intervention. Material and Methods: Between January and March 2008, 42 inguinal hernioplasty procedures have been performed using the 3PAWS model of ReeTrakt™ a self-retaining, low profile retractor. Equivalent patients samples, in which operations were performed using conventional retraction devices, were considered for comparison of the intra and postoperative results. Results: In all of the 42 inguinal hernioplasty procedures performed, the ReeTrakt™ system has simplified the perform…

Mastoidectomy in surgical procedures to treat retraction pockets: a single-center experience and review of the literature

2022

Abstract Purpose Retraction pocket (RP) is a common event affecting the middle ear when a negative pressure within it causes a retraction of a single part of the tympanic membrane (TM). Patients can be asymptomatic or can experience hearing loss, fullness feeling and/or ear discharge. RP can be stable or develop a cholesteatoma; aim of the study was to investigate if mastoidectomy may play a role in the surgical management of patients suffering from RP, both reporting our experience and discussing the existing literature. Methods Fifty-one patients affected by RP were referred for surgery and randomly divided into two groups. Patients of G1 group underwent tympanoplasty with mastoidectomy, …