double space
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2021 ◽  
Vol 108 (Supplement_6) ◽  
Author(s):  
L Ishak ◽  
N Kostoulas

Abstract Presentation A 69-year-old male presented with rapidly worsening symptoms of breathlessness, productive cough, and weight loss. Examination revealed a deviated trachea, and no breath sounds on auscultation of the left side of the chest. Investigations Chest X-ray revealed a giant mass associated with a large pleural effusion, subtotal lung collapse and mediastinal shift. FEV1 was 39% predicted and DLCO 62% predicted. Management Due to the severity of presentation, urgent pleural inspection, drainage, and biopsy were carried out. Compression of the heart resulting in tamponade with increased heartrate and breathlessness was suspected Further investigations and management Pleural biopsies and pleural fluid cytology were negative for malignancy. PET-CT showed mild avidity. Definitive management was tumour mass resection via left double space open thoracotomy. Macroscopy/Microscopy/Immunohistopathology Intra-operatively, the tumour was giant, occupying three quarters of the chest cavity. It measured 21 × 14×8 cm. The whole lung was attached to the chest wall with adhesions. Microscopy revealed patternless architecture, high vascularity, hypercellularity, necrosis, elongated nuclei, pale cytoplasms and mitotic activity of 2-3 mitotic figures per 10-highpower-fields. Immunohistochemistry stained positive with CD34, BCL2, CD99, Ki-67 and STAT6. Diagnosis of SFT was suspected; malignant potential could not be predicted. Follow-up was with repeat CT scans for five years. Recurrence risk was given as 20%. Learning points


2021 ◽  
Vol 2021 (3) ◽  
Author(s):  
Lj. Davidović ◽  
I. Ivanišević ◽  
B. Sazdović

Abstract We consider the symmetries of a closed bosonic string, starting with the general coordinate transformations. Their generator takes vector components ξμ as its parameter and its Poisson bracket algebra gives rise to the Lie bracket of its parameters. We are going to extend this generator in order for it to be invariant upon self T-duality, i.e. T-duality realized in the same phase space. The new generator is a function of a 2D double symmetry parameter Λ, that is a direct sum of vector components ξμ, and 1-form components λμ. The Poisson bracket algebra of a new generator produces the Courant bracket in a same way that the algebra of the general coordinate transformations produces Lie bracket. In that sense, the Courant bracket is T-dual invariant extension of the Lie bracket. When the Kalb-Ramond field is introduced to the model, the generator governing both general coordinate and local gauge symmetries is constructed. It is no longer self T-dual and its algebra gives rise to the B-twisted Courant bracket, while in its self T-dual description, the relevant bracket becomes the θ-twisted Courant bracket. Next, we consider the T-duality and the symmetry parameters that depend on both the initial coordinates xμ and T-dual coordinates yμ. The generator of these transformations is defined as an inner product in a double space and its algebra gives rise to the C-bracket.


2021 ◽  
Vol 21 (1) ◽  
pp. 63-73
Author(s):  
Hans Havlicek ◽  
Stefano Pasotti ◽  
Silvia Pianta

Abstract We focus on the description of the automorphism group Γ∥ of a Clifford-like parallelism ∥ on a 3-dimensional projective double space (ℙ(HF ), ∥ ℓ , ∥ r ) over a quaternion skew field H (of any characteristic). We compare Γ∥ with the automorphism group Γ ℓ of the left parallelism ∥ ℓ , which is strictly related to Aut(H). We build up and discuss several examples showing that over certain quaternion skew fields it is possible to choose ∥ in such a way that Γ∥ is either properly contained in Γ ℓ or coincides with Γ ℓ even though ∥ ≠ ∥ ℓ .


Author(s):  
Wanpeng Tan

A dynamic view is conjectured for not only the universe but also the underlying theories in contrast to the convectional pursuance of single unification theory. As the 4 -d spacetime evolves dimension by dimension via the spontaneous symmetry breaking mechanism, supersymmetric mirror models consistently emerge one by one at different energy scales and scenarios involving different sets of particle species and interactions. Starting from random Planck fluctuations, the time dimension and its arrow are born in the time inflation process as the gravitational strength is weakened under a 1-d model of a “timeron” scalar field. The “ timeron” decay then starts the hot big bang and generates Majorana fermions and U(1) gauge bosons in 2-d spacetime. The next spontaneous symmetry breaking results in two space inflaton fields leading to a double space inflation process and emergence of two decoupled sectors of ordinary and mirror particles. In fully extended 4-d spacetime, the supersymmetric standard model with mirror matter before the electroweak phase transition and the subsequent pseudo-supersymmetric model due to staged quark condensation as previously proposed are justified. A set of principles are postulated under t his new framework. In particular, new understanding of the evolving supersymmetry and Z2 or generalized mirror symmetry is presented.


2020 ◽  
Vol 13 (3) ◽  
pp. 477-481
Author(s):  
Khalaf Khatatneh ◽  
Ashraf Odeh ◽  
Ashraf Mashaleh ◽  
Hind Hamadeen

Introduction: The single space and the double space (DS). In this procedure, an image is used to watermark a digital database, where the image bytes are divided into binary strings that block the text attributes of the selected database, we proposed an algorithm to defend against four common database attacks. Objective: Perform the watermark is Embedding and makes extraction of the watermark. We also describe the principal of the Embedding and extraction the watermark. Methods: The procedure to extract the watermark does not require knowledge of the original database that does not carry the same watermark. This feature is extremely important because it allows the discovery of a watermark in a copy of the original database, regardless of the subsequent updates to the asset. The extraction procedure is a direct reflection of the procedure used to embed the watermark is six steps. Results: Using new algorithm ability to develop a database watermark that would make it difficult for an attacker to remove or change the watermark without discovering the value of the object. To be judged effective, the database algorithm had to be able to create a strong enough watermark that could sustain the security of the database in the face of the following four types of attack: deletion of a sub-dataset, addition of a sub-dataset. Conclusion: The performance of the proposed algorithm was assessed in respect of its ability to defend the database against four common attacks for all tuples selection.


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