Bundle structures on manifolds

1966 ◽  
Vol 62 (1) ◽  
pp. 19-22
Author(s):  
J. B. Wagoner
Keyword(s):  
Total Space ◽  
Manifold With Boundary ◽  
Main Technique ◽  
Metastable Range ◽  
Disc Bundle

This note gives homotopy-theoretic criteria in the metastable range for an (n + l)-manifold with boundary to be diffeomorphic to the total space of an l-disc bundle over a closed n-manifold and for two such structures to be equivalent. The results are similar to some theorems of (8) and the main technique used in the proofs is surgery on a map ((l), pp. 42–46, (7), (10)). All manifolds will be smooth.

To Discriminate in Order to Fight Discrimination

2017 ◽  
Author(s):  
Dolores Morondo Taramundi
Keyword(s):  
Human Rights ◽  
United Kingdom ◽  
The Other ◽  
The United Kingdom ◽  
European Court ◽  
Main Technique ◽  
Antidiscrimination Law ◽  
The One ◽  
Paradoxical Results ◽  
Conflicts Of Rights

This chapter analyses arguments regarding conflicts of rights in the field of antidiscrimination law, which is a troublesome and less studied area of the growing literature on conflicts of rights. Through discussion of Ladele and McFarlane v. The United Kingdom, a case before the European Court of Human Rights, the chapter examines how the construction of this kind of controversy in terms of ‘competing rights’ or ‘conflicts of rights’ seems to produce paradoxical results. Assessment of these apparent difficulties leads the discussion in two different directions. On the one hand, some troubles come to light regarding the use of the conflict of rights frame itself in the field of antidiscrimination law, particularly in relation to the main technique (‘balancing of rights’) to solve them. On the other hand, some serious consequences of the conflict of rights frame on the development of the antidiscrimination theory of the ECtHR are unearthed.

scholarly journals Efficient Private Conjunctive Query Protocol Over Encrypted Data

Cryptography ◽  
2021 ◽  
Vol 5 (1) ◽  
pp. 2
Author(s):  
Tushar Kanti Saha ◽  
Takeshi Koshiba
Keyword(s):  
Homomorphic Encryption ◽  
Data Access ◽  
Conjunctive Query ◽  
Conjunctive Queries ◽  
Private Data ◽  
Binary Format ◽  
Main Technique ◽  
Batch Technique ◽  
Outsourced Database ◽  
Packing Method

Conjunctive queries play a key role in retrieving data from a database. In a database, a query containing many conditions in its predicate, connected by an “and/&/∧” operator, is called a conjunctive query. Retrieving the outcome of a conjunctive query from thousands of records is a heavy computational task. Private data access to an outsourced database is required to keep the database secure from adversaries; thus, private conjunctive queries (PCQs) are indispensable. Cheon, Kim, and Kim (CKK) proposed a PCQ protocol using search-and-compute circuits in which they used somewhat homomorphic encryption (SwHE) for their protocol security. As their protocol is far from being able to be used practically, we propose a practical batch private conjunctive query (BPCQ) protocol by applying a batch technique for processing conjunctive queries over an outsourced database, in which both database and queries are encoded in binary format. As a main technique in our protocol, we develop a new data-packing method to pack many data into a single polynomial with the batch technique. We further enhance the performances of the binary-encoded BPCQ protocol by replacing the binary encoding with N-ary encoding. Finally, we compare the performance to assess the results obtained by the binary-encoded BPCQ protocol and the N-ary-encoded BPCQ protocol.

scholarly journals Endoscopic Study of the Oral and Pharyngeal Cavities in the Common Dolphin, Striped Dolphin, Risso’s Dolphin, Harbour Porpoise and Pilot Whale: Reinforced with Other Diagnostic and Anatomic Techniques

Animals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1507
Author(s):  
Álvaro García de los Ríos y Loshuertos ◽  
Marta Soler Laguía ◽  
Alberto Arencibia Espinosa ◽  
Francisco Martínez Gomariz ◽  
Cayetano Sánchez Collado ◽  
...  
Keyword(s):  
Oral Cavity ◽  
Common Dolphin ◽  
Resonance Imaging ◽  
Pilot Whale ◽  
Anatomical Structures ◽  
Vascular Plexus ◽  
Endoscopic Study ◽  
Main Technique ◽  
The Common ◽  
Magnetic Resonance Imaging Mri

In this work, the fetal and newborn anatomical structures of the dolphin oropharyngeal cavities were studied. The main technique used was endoscopy, as these cavities are narrow tubular spaces and the oral cavity is difficult to photograph without moving the specimen. The endoscope was used to study the mucosal features of the oral and pharyngeal cavities. Two pharyngeal diverticula of the auditory tubes were discovered on either side of the choanae and larynx. These spaces begin close to the musculotubaric channel of the middle ear, are linked to the pterygopalatine recesses (pterygoid sinus) and they extend to the maxillopalatine fossa. Magnetic Resonance Imaging (MRI), osteological analysis, sectional anatomy, dissections, and histology were also used to better understand the function of the pharyngeal diverticula of the auditory tubes. These data were then compared with the horse’s pharyngeal diverticula of the auditory tubes. The histology revealed that a vascular plexus inside these diverticula could help to expel the air from this space to the nasopharynx. In the oral cavity, teeth remain inside the alveolus and covered by gums. The marginal papillae of the tongue differ in extension depending on the fetal specimen studied. The histology reveals that the incisive papilla is vestigial and contain abundant innervation. No ducts were observed inside lateral sublingual folds in the oral cavity proper and caruncles were not seen in the prefrenular space.

Cryo-EM Is a Powerful Tool, But Helical Applications Can Have Pitfalls

Soft Matter ◽  
2021 ◽  
Author(s):  
Edward Egelman ◽  
Fengbin Wang
Keyword(s):  
Electron Microscopy ◽  
Structural Biology ◽  
Macromolecular Complexes ◽  
Atomic Structures ◽  
Cryo Electron Microscopy ◽  
Main Technique

In structural biology, cryo-electron microscopy (cryo-EM) has emerged as the main technique for determining the atomic structures of macromolecular complexes. This has largely been due to the introduction of direct...

scholarly journals Transcranial Direct Current Stimulation as a Treatment Tool for Mild Traumatic Brain Injury

2021 ◽  
Vol 11 (6) ◽  
pp. 806
Author(s):  
Thorsten Rudroff ◽  
Craig D. Workman
Keyword(s):  
Traumatic Brain Injury ◽  
Brain Injury ◽  
Mild Traumatic Brain Injury ◽  
Direct Current ◽  
Transcranial Direct Current Stimulation ◽  
Therapeutic Potential ◽  
Repetitive Transcranial Magnetic Stimulation ◽  
Motor Impairment ◽  
Direct Current Stimulation ◽  
Main Technique

Mild traumatic brain injury (mTBI) has been defined as a transient (<24 h) condition of confusion and/or loss of consciousness for less than 30 min after brain injury and can result in short- and long-term motor and cognitive impairments. Recent studies have documented the therapeutic potential of non-invasive neuromodulation techniques for the enhancement of cognitive and motor function in mTBI. Alongside repetitive transcranial magnetic stimulation (rTMS), the main technique used for this purpose is transcranial direct current stimulation (tDCS). The focus of this review was to provide a detailed, comprehensive (i.e., both cognitive and motor impairment) overview of the literature regarding therapeutic tDCS paradigms after mTBI. A publication search of the PubMed, Scopus, CINAHL, and PsycINFO databases was performed to identify records that applied tDCS in mTBI. The publication search yielded 14,422 records from all of the databases, however, only three met the inclusion criteria and were included in the final review. Based on the review, there is limited evidence of tDCS improving cognitive and motor performance. Surprisingly, there were only three studies that used tDCS in mTBI, which highlights an urgent need for more research to provide additional insights into ideal therapeutic brain targets and optimized stimulation parameters.

scholarly journals Variation formulas for principal functions, II: Applications to variation for harmonic spans

2011 ◽  
Vol 204 ◽  
pp. 19-56 ◽  
Author(s):  
Sachiko Hamano ◽  
Fumio Maitani ◽  
Hiroshi Yamaguchi
Keyword(s):  
Direct Application ◽  
Total Space ◽  
Geometric Meaning ◽  
Principal Function ◽  
Variation Formula ◽  
Circular Slit ◽  
Moving Domain

AbstractA domainD⊂ Czadmits the circular slit mappingP(z) fora, b∈Dsuch thatP(z) – 1/(z–a) is regular ataandP(b) = 0. We callp(z) =log|P(z)|theLi-principal functionandα= log |P′(b)| theL1-constant, and similarly, the radial slit mappingQ(z) implies theL0-principal functionq(z) and theL0-constantβ. We calls=α–βtheharmonic spanfor (D, a, b). We show the geometric meaning ofs. Hamano showed the variation formula for theL1-constantα(t) for the moving domainD(t) in Czwitht∈B:= {t∈ C: |t| &lt;ρ}. We show the corresponding formula for theL0-constantβ(t) forD(t) and combine these to prove that, if the total spaceD =∪t∈B(t, D(t)) is pseudoconvex inB× Cz, thens(t) is subharmonic onB. As a direct application, we have the subharmonicity of log coshd(t) onB, whered(t) is the Poincaré distance betweenaandbonD(t).

scholarly journals Freeze–Thaw Effect on Road Concrete Containing Blast Furnace Slag: NMR Relaxometry Investigations

Materials ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3288
Author(s):  
Liliana Maria Nicula ◽  
Ofelia Corbu ◽  
Ioan Ardelean ◽  
Andrei Victor Sandu ◽  
Mihai Iliescu ◽  
...  
Keyword(s):  
Blast Furnace ◽  
Blast Furnace Slag ◽  
Nmr Relaxation ◽  
Invasive Technique ◽  
Freeze Thaw ◽  
Nmr Relaxometry ◽  
Main Technique ◽  
Relaxation Measurements ◽  
Furnace Slag ◽  
Standard Techniques

The present work investigates the effect of freeze–thaw cycles on the porosity of three mixtures of road concrete containing blast furnace slag in comparison with two mixtures made with conventional materials. The main technique used in our investigations is nuclear magnetic resonance (NMR) relaxometry. This permitted the extraction of information with respect to the freeze–thaw effect on pore-size distribution, which influences both the mechanical strength and the molecular transport through the material. Moreover, by using this technique, the structure of the air voids was analyzed for the entire pore system in the cement paste and the aggregate particles. The samples under study were first dried in a vacuum oven and then saturated with water or cyclohexane where the distribution of the transverse relaxation times of the protons was recorded. The NMR relaxation measurements were performed on samples extracted from specimens maintained at 300 freeze–thaw cycles and on control samples extracted from specimens kept in water during the freeze–thaw period. Scanning Electron Microscopy (SEM) was used to analyze the microstructure of concrete samples in order to obtain information about the pore sizes and the distance between them. The results from the NMR relaxation measurements were consistent with those obtained by using standard techniques for determining the porosity and the freeze–thaw resistances. The investigations made it possible to establish the optimal composition of blast furnace slag that can be incorporated into road concrete compositions. This non-invasive technique can also complete standard techniques for assessing the porosity and the progress of internal cracks during the freeze–thaw test.

Discussion of Criteria of Shear Strength Reduction FEM

2011 ◽  
Vol 243-249 ◽  
pp. 1279-1282
Author(s):  
Li Hong Chen ◽  
Shu Yu ◽  
Hong Tao Zhang
Keyword(s):  
Shear Strength ◽  
Complex Geometry ◽  
Strength Reduction ◽  
Nonlinear Material ◽  
Elastoplastic Model ◽  
Material Models ◽  
Main Technique ◽  
Failure Point ◽  
Straight Lines ◽  
Shear Strength Reduction

Shear strength reduction finite element method (SSRFEM) has been a main technique for stability analysis of slope. Although SSRFEM has advantages to deal with complex geometry and nonlinear material, the criteria for failure is still argued. Ideal elastoplastic model and rheological model were both adopted, and the results of computation showed that using the intersection of two straight lines as failure point was more appropriate. The usage and advantage of two different material models was compared.

scholarly journals SCATTERING, GREEN’S FUNCTIONS AND SYMMETRIES IN A TOTAL SPACE OF A DIRAC MONOPOLE FIBRE BUNDLE

1991 ◽  
Vol 06 (04) ◽  
pp. 577-598 ◽  
Author(s):  
A.G. SAVINKOV ◽  
A.B. RYZHOV
Keyword(s):  
Green's Functions ◽  
Principal Bundle ◽  
Fibre Bundle ◽  
Green’S Functions ◽  
Wave Functions ◽  
Total Space ◽  
Dirac Monopole ◽  
Hidden Symmetries ◽  
Scattering Wave ◽  
A Charge

The scattering wave functions and Green’s functions were found in a total space of a Dirac monopole principal bundle. Also, hidden symmetries of a charge-Dirac monopole system and those joining the states relating to different topological charges n=2eg were found.

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