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Gravitational lensing in WDM cosmologies: the cross-section for giant arcs
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The nature of the dark sector of the Universe remains one of the outstanding problems in modern cosmology, with the search for new observational probes guiding the development of the next generation of observational facilities. Clues come from tension between the predictions from Λ cold dark matter (ΛCDM) and observations of gravitationally lensed galaxies. Previous studies showed that galaxy clusters in the ΛCDM are not strong enough to reproduce the observed number of lensed arcs. This work aims to constrain the warm dark matter (WDM) cosmologies by means of the lensing efficiency of galaxy clusters drawn from these alternative models. The lensing characteristics of two samples of simulated clusters in the Λ warm dark matter and ΛCDM cosmologies have been studied. The results show that even though the cold dark matter (CDM) clusters are more centrally concentrated and contain more substructures, the WDM clusters have slightly higher lensing efficiency than their CDM counterparts. The key difference is that WDM clusters have more extended and more massive subhaloes than CDM analogues. These massive substructures significantly stretch the critical lines and caustics and hence they boost the lensing efficiency of the host halo. Despite the increase in the lensing efficiency due to the contribution of massive substructures in the WDM clusters, this is not enough to resolve the arc statistics problem.

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Publication Date
Wed Sep 10 2014
Journal Name
Monthly Notices Of The Royal Astronomical Society
Warm dark haloes accretion histories and their gravitational signatures
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We study clusters in warm dark matter (WDM) models of a thermally produced dark matter particle 0.5 keV in mass. We show that, despite clusters in WDM cosmologies having similar density profiles as their cold dark matter (CDM) counterparts, the internal properties, such as the amount of substructure, show marked differences. This result is surprising as clusters are at mass scales that are a thousand times greater than that at which structure formation is suppressed. WDM clusters gain significantly more mass via smooth accretion and contain fewer substructures than their CDM brethren. The higher smooth mass accretion results in subhaloes which are physically more extended and less dense. These fine-scale differences can be probed by strong

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Publication Date
Thu Apr 27 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Complete Arcs in Projective Plane PG (2,11) Over Galois field
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    In this work, we construct complete (K, n)-arcs in the projective plane over Galois field GF (11), where 12 2 ≤ ≤ n  ,by using geometrical method (using the union of some maximum(k,2)- Arcs , we found (12,2)-arc, (19,3)-arc , (29,4)-arc, (38,5)-arc , (47,6)-arc, (58,7)-arc, (68,6)-arc, (81,9)-arc, (96,10)-arc, (109,11)-arc, (133,12)-arc, all of them are complete arc in PG(2, 11) over GF(11).  

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Publication Date
Sat Apr 01 2023
Journal Name
Baghdad Science Journal
New sizes of complete (k, 4)-arcs in PG(2,17)
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              In this paper, the packing problem for complete (  4)-arcs in  is partially solved. The minimum and the maximum sizes of complete (  4)-arcs in  are obtained. The idea that has been used to do this classification is based on using the algorithm introduced in Section 3 in this paper. Also, this paper establishes the connection between the projective geometry in terms of a complete ( , 4)-arc in  and the algebraic characteristics of a plane quartic curve over the field  represented by the number of its rational points and inflexion points. In addition, some sizes of complete (  6)-arcs in the projective plane of order thirteen are established, namely for  = 53, 54, 55, 56.

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Publication Date
Sun May 28 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
The Maximum Complete (k,n)-Arcs in the Projective Plane PG(2,4) By Geometric Method
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A (k,n)-arc A in a finite projective plane PG(2,q) over Galois field GF(q), q=pⁿ for same prime number p and some integer n≥2, is a set of k points, no n+1 of which are collinear.  A (k,n)-arc is complete if it is not contained in a(k+1,n)-arc.  In this paper, the maximum complete (k,n)-arcs, n=2,3 in PG(2,4) can be constructed from the equation of the conic.

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Publication Date
Mon Aug 03 2020
Journal Name
Rawal Medical Journal
Functional outcomes of sandwich reconstruction technique for giant cell tumor around the knee joint
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Objective: To evaluate the functional outcomes after extended curettage and reconstruction using a combination of bone graft and bone cement (sandwich). Methodology: In this prospective case series 16 skeletally mature patients with primary giant cell tumor around the knee were included. Patients with previous surgically treated, malignant transformation, degenerative knee changes and those presenting with pathological fracture were excluded. The tumor was excised with bone graft filling space beneath the articular cartilage and a block of gel foam was placed over the cortical surface of picked bone graft. Remaining cavity was filled with polymethylmethacrylate cement (sandwich) with or without internal fixation. The func tional evaluation

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Publication Date
Thu Dec 29 2016
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Some Results on The Complete Arcs in Three Dimensional Projective Space Over Galois Field
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        The aim of this paper is to introduce the definition of projective 3-space over Galois field GF(q), q = pm, for some prime number p and some integer m.

        Also the definitions of (k,n)-arcs, complete arcs, n-secants, the index of the point and the projectively equivalent arcs are given.

        Moreover some theorems about these notations are proved.

 

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Publication Date
Thu Apr 27 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Determining of Cross Sections for 16O(n,α)13C reaction from Cross Sections of 13C(α,n)16O for the ground state
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  In this study, light elements for 13C , 16O for  (α,n) and (n,α) reactions as well as α-particle energy  from 2.7 MeV  to 3.08 MeV are used as far as the data of reaction cross sections are available. The more recent cross sections data of (α,n) and (n,α) reactions are reproduced in fine steps 0.02 MeV for  16O (n,α) 13C  in the specified energy range, as well as cross section (α,n)  values were derived from the published data of (n,α) as a function of α-energy in the same fine energy steps by using the principle inverse reactions. This calculation involves only the ground state of  13C , 16O  in the reactions 13C (α,n) 16O  and  16O (n,α) 13C.

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Publication Date
Mon Aug 14 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Study of Cross Sections for 10 Li 10 Reaction From Cross Sections of Li a,n) Reaction Using the Reciprocity Theory for the Ground State
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In this study, light elements Li ,10B for (a,n) and (n,a) reactions
as well as o-particle energy from threshold energy to 10 MeV are
used according to the available data of reaction cross sections. The
more recent cross sections data of (a,n) and (n,a) reactions are
reproduced in fine steps 42 Kev for 10B(n,o) Li in the specified
energy range, as well as cross section (o,n) Values were derived from
the published data of (n,a) as a function of a-energy in the same fine
energy steps by using the principle inverse reactions. This calculation
involves only the ground state of Li OB in the reactions 'Li(a,n) B
B (n,a) Li
Introduction
When two charged nuclei overcome their Coulomb repulsion, a
rearrangement

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Publication Date
Sun Aug 13 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Determining of Cross Sections for 22Na (n,α) 19F reaction from Cross Sections of 19F(α,n) 22Na reaction using the reciprocity theory for the ground state
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       In this study, light elements 19F ,22Na for  (α,n) and (n,α) reactions as well as α-particle energy  from a threshold energy  to 10 MeV are used according to the available data of reaction cross sections.  The more recent cross sections data of (α,n) and (n,α) reactions are reproduced in fine steps 86.4 KeV for 22Na (n,α) 19F  in the specified energy range, as well as cross section (α,n)  values were derived from the published data of (n,α) as a function of αenergy in the same fine energy steps by using the principle inverse reactions. This calculation involves only the ground state of  19F ,22Na in the reactions 19F (α,n) 22Na ,  2

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Publication Date
Thu Apr 17 2025
Journal Name
Journal Of Baghdad College Of Dentistry
Immunohistochemical assessment of tumor suppressor gene Wwox in relation to proliferative marker KI67 proteins expression in giant cell lesions of the jaws and giant cell tumor of long bones
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Background: Peripheral giant cell lesion (PGCL) and central giant cell lesion (CGCL) of the jaws have a distinct clinical behavior.Giant cell tumour (GCT) is a benign locally aggressive neoplasm affects the long bones. Both lesions are characterized histologically by multinucleated giant cells in a background of ovoid to spindle-shaped mesenchymal cells. The WW domain-containing oxidoreductase (WWOX) gene is located at 16q23.1–16q23.2, a region that spans the second most common human fragile site, FRA16D, at 16q23.2.The Ki-67 antigen is a nuclear protein that is associated with and may be necessary for cellular proliferation.Ki-67 protein is present during all active phases of the cell cycle (G1, S, G2, and mitosis), but is absent fr

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