Matter collineation classification of Bianchi type II spacetime

2006 ◽  
Vol 38 (9) ◽  
pp. 1331-1346 ◽  
Author(s):  
U. Camci ◽  
E. Sahin
Keyword(s):  
Bianchi Type ◽  
Type Ii ◽  
Matter Collineation

Ricci inheritance collineations in Bianchi type II spacetime

2016 ◽  
Vol 31 (17) ◽  
pp. 1650102 ◽  
Author(s):  
Tahir Hussain ◽  
Sumaira Saleem Akhtar ◽  
Ashfaque H. Bokhari ◽  
Suhail Khan
Keyword(s):  
Lie Algebra ◽  
Ricci Tensor ◽  
Bianchi Type ◽  
Complete Classification ◽  
Type Ii

In this paper, we present a complete classification of Bianchi type II spacetime according to Ricci inheritance collineations (RICs). The RICs are classified considering cases when the Ricci tensor is both degenerate as well as non-degenerate. In case of non-degenerate Ricci tensor, it is found that Bianchi type II spacetime admits 4-, 5-, 6- or 7-dimensional Lie algebra of RICs. In the case when the Ricci tensor is degenerate, majority cases give rise to infinitely many RICs, while remaining cases admit finite RICs given by 4, 5 or 6.

Morphological types of spermatheca in Coreidae: bearing on intra-familial classification and tribal-groupings (Hemiptera: Heteroptera)

Zootaxa ◽  
2020 ◽  
Vol 4834 (4) ◽  
pp. 451-501
Author(s):  
DOMINIQUE PLUOT-SIGWALT ◽  
PIERRE MOULET
Keyword(s):  
Western Hemisphere ◽  
Type I ◽  
Type Ii ◽  
Type Iii ◽  
Spermathecal Duct ◽  
Eastern Hemisphere ◽  
Intermediate Part ◽  
Muscular Pump ◽  
Familial Classification

The morphology of the spermatheca is described in 109 species of 86 genera representing all four currently recognised subfamilies of Coreidae, covering the undivided Hydarinae, both tribes of Pseudophloeinae, all three tribes of Meropachyinae and 27 of the 32 tribes of Coreinae. Three types of spermatheca are recognised. Type I is bipartite, consisting only of a simple tube differentiated into distal seminal receptacle and proximal spermathecal duct and lacks the intermediate part present in most Pentatomomorpha, in which it serves as muscular pump. Type II is also bipartite but more elaborate in form with the receptacle generally distinctly wider than the duct. Type III is tripartite, with receptacle, duct and an often complex intermediate part. Four subtypes are recognised within type III. Type I is found only in Hydarinae and type II only in Pseudophloeinae. Type III is found in both Coreinae and Meropachyinae. Subtype IIIA (“Coreus-group”) unites many tribes from the Eastern Hemisphere and only one (Spartocerini) from the Western Hemisphere. Subtypes IIIB (“Nematopus-group”) and IIID (“Anisoscelis-group”) are confined to taxa from the Western Hemisphere and subtype IIIC (“Chariesterus-group”) is found in tribes from both hemispheres. The polarity of several characters of the intermediate part and some of the spermathecal duct is evaluated, suggesting autapomorphies or apomorphies potentially relevant to the classification of Coreidae at the sufamilial and tribal levels. Characters of the intermediate part strongly indicate that the separation of Meropachyinae and Coreinae as currently constituted cannot be substantiated. The tribes Anisoscelini, Colpurini, Daladerini and Hyselonotini are heterogeneous, each exhibiting two subtypes of spermatheca, and probably polyphyletic. Two tribes, Cloresmini and Colpurini, requiring further investigation remain unplaced. This study demonstrates the great importance of characters of the spermatheca, in particular its intermediate part, for research into the phylogeny and taxonomy of Pentatomomorpha. 

Bianchi-Type II String Cosmological Models with Bulk Viscosity

2004 ◽  
Vol 41 (5) ◽  
pp. 726-728 ◽  
Author(s):  
Wang Xing-Xiang
Keyword(s):  
Bulk Viscosity ◽  
Bianchi Type ◽  
Cosmological Models ◽  
Type Ii

Split spinal cord malformations in children

1998 ◽  
Vol 88 (1) ◽  
pp. 57-65 ◽  
Author(s):  
Yusuf Ersşahin ◽  
Saffet Mutluer ◽  
Sevgül Kocaman ◽  
Eren Demirtasş
Keyword(s):  
Spinal Cord ◽  
Neurological Deficits ◽  
Single Type ◽  
Type I ◽  
Type Ii ◽  
Content Type ◽  
Spinal Lesion ◽  
The Mean ◽  
Fine Print

Object. The authors reviewed and analyzed information on 74 patients with split spinal cord malformations (SSCMs) treated between January 1, 1980 and December 31, 1996 at their institution with the aim of defining and classifying the malformations according to the method of Pang, et al. Methods. Computerized tomography myelography was superior to other radiological tools in defining the type of SSCM. There were 46 girls (62%) and 28 boys (38%) ranging in age from less than 1 day to 12 years (mean 33.08 months). The mean age (43.2 months) of the patients who exhibited neurological deficits and orthopedic deformities was significantly older than those (8.2 months) without deficits (p = 0.003). Fifty-two patients had a single Type I and 18 patients a single Type II SSCM; four patients had composite SSCMs. Sixty-two patients had at least one associated spinal lesion that could lead to spinal cord tethering. After surgery, the majority of the patients remained stable and clinical improvement was observed in 18 patients. Conclusions. The classification of SSCMs proposed by Pang, et al., will eliminate the current chaos in terminology. In all SSCMs, either a rigid or a fibrous septum was found to transfix the spinal cord. There was at least one unrelated lesion that caused tethering of the spinal cord in 85% of the patients. The risk of neurological deficits resulting from SSCMs increases with the age of the patient; therefore, all patients should be surgically treated when diagnosed, especially before the development of orthopedic and neurological manifestations.

scholarly journals String cosmology in LRS Bianchi type-II dusty Universe with time-decaying vacuum energy density Λ

Pramana ◽  
2012 ◽  
Vol 78 (4) ◽  
pp. 651-665 ◽  
Author(s):  
HASSAN AMIRHASHCHI ◽  
HOSEIN MOHAMADIAN
Keyword(s):  
Energy Density ◽  
Vacuum Energy ◽  
Bianchi Type ◽  
String Cosmology ◽  
Vacuum Energy Density ◽  
Type Ii

Bianchi Type-II Bulk Viscous String Cosmological Models in General Relativity

2010 ◽  
Vol 49 (8) ◽  
pp. 1712-1718 ◽  
Author(s):  
Atul Tyagi ◽  
Keerti Sharma
Keyword(s):  
General Relativity ◽  
Bianchi Type ◽  
Cosmological Models ◽  
Type Ii ◽  
Bulk Viscous

scholarly journals Comment on the two ‘‘new’’ classes of Bianchi type II solutions

1987 ◽  
Vol 28 (6) ◽  
pp. 1382-1382 ◽  
Author(s):  
Dieter Lorenz‐Petzold
Keyword(s):  
Bianchi Type ◽  
Type Ii

Classical solutions to Bianchi type II spacetimes in f(R) theory of gravity

2022 ◽  
Author(s):  
U. Obaidullah ◽  
S. Jamal
Keyword(s):  
Bianchi Type ◽  
Classical Solutions ◽  
Type Ii ◽  
Theory Of Gravity

scholarly journals A FURTHER STUDY ON THE BIOLOGIC CLASSIFICATION OF PNEUMOCOCCI

1915 ◽  
Vol 22 (6) ◽  
pp. 804-819 ◽  
Author(s):  
Oswald T. Avery
Keyword(s):  
The Other ◽  
Type Ii ◽  
Respective Group ◽  
Immune Reactions ◽  
Subgroup Ii ◽  
Typical Type ◽  
Immunity Reaction ◽  
Pneumococcus Type

1. At least three subgroups of Pneumococcus Type II may be recognized by specific immune reactions. They have been called Subgroups II A, II B, and II X. 2. That the organisms of these three subgroups are biologically related to Pneumococcus Type II is shown by the following facts: (a) Agglutination with Antipneumococcus Serum II. (b) Protection with Antipneumococcus Serum II, except Subgroup II X. (c) Absorption of Antipneumococcus Serum II with typical Type II pneumococcus removes the antibodies for all subgroups, (d) Absorption of Antipneumococcus Serum II with a member of Subgroups II A or II B removes only the antibodies for the homologous subgroup. Absorption of Antipneumococcus Serum II with any given member of Subgroup II X removes the antibodies for that particular strain only. 3. That the three subgroups, although biologically related to Pneumococcus Type II, possess, nevertheless, specific differential characterswhich separate them one from another, is evidenced by thefollowing facts: (a) The organisms of any subgroup are not agglutinated bythe antisera of the other two subgroups. (b) They are not protected against by the sera of the other subgroups. (c) They do not absorb from Antipneumococcus Serum II the specific immune bodies of the other subgroups. 4. Subgroups II A and II B are characterized by immunity reactions identical within the respective group. 5. Subgroup II X consists of heterogeneous strains which do not cross in their immunity reaction with each other or with Subgroups II A or II B.

Sign in / Sign up

Export Citation Format

Share Document