scholarly journals The Lifting-Extension Problem for Duchain Complexes of Dwyer and Kan

2015 ◽  
Vol 48 (1) ◽  
Author(s):  
Jan Spaliński
Keyword(s):  
Commutative Diagram ◽  
Chain Complex ◽  
Category Structure ◽  
Extension Problem ◽  
Weak Equivalence ◽  
Cochain Complex ◽  
Common Extension ◽  
A Chain ◽  
The Right ◽  
Countably Infinite

AbstractA duchain complex of W. Dwyer and D. Kan is a common extension of the notions of a chain complex and a cochain complex.Given a square commutative diagram of duchain complexes, the lifting-extension problem asks whether there exists a diagonal map making the two resulting triangles commute. Duchain complexes have a model category structure, and hence a lift exists if the left vertical map is a cofibration, the right vertical map is a fibration, and one of them is a weak equivalence.We show that it is possible to replace the two conditions above, by a countably infinite, bigraded, family of conditions which guarantee the existence of a lift.

Right-Hemisphere Specialization for Contour Grouping

2014 ◽  
Vol 61 (5) ◽  
pp. 331-339 ◽  
Author(s):  
Gregor Volberg
Keyword(s):  
Right Hemisphere ◽  
Contour Detection ◽  
Global Processing ◽  
Detection Accuracy ◽  
Frequency Spectra ◽  
Visual Hemifield ◽  
Spatial Frequencies ◽  
A Chain ◽  
The Right ◽  
Hemisphere Specialization

Previous studies often revealed a right-hemisphere specialization for processing the global level of compound visual stimuli. Here we explore whether a similar specialization exists for the detection of intersected contours defined by a chain of local elements. Subjects were presented with arrays of randomly oriented Gabor patches that could contain a global path of collinearly arranged elements in the left or in the right visual hemifield. As expected, the detection accuracy was higher for contours presented to the left visual field/right hemisphere. This difference was absent in two control conditions where the smoothness of the contour was decreased. The results demonstrate that the contour detection, often considered to be driven by lateral coactivation in primary visual cortex, relies on higher-level visual representations that differ between the hemispheres. Furthermore, because contour and non-contour stimuli had the same spatial frequency spectra, the results challenge the view that the right-hemisphere advantage in global processing depends on a specialization for processing low spatial frequencies.

scholarly journals Small changes in ball position at address cause a chain effect in golf swing

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sung Eun Kim ◽  
Jangyun Lee ◽  
Sae Yong Lee ◽  
Hae-Dong Lee ◽  
Jae Kun Shim ◽  
...  
Keyword(s):  
Ground Reaction Force ◽  
Reaction Force ◽  
Statistical Parametric Mapping ◽  
Golf Swing ◽  
Whole Body ◽  
Centre Of Mass ◽  
Body Segment ◽  
A Chain ◽  
Professional Golfers ◽  
The Right

AbstractThe purpose of this study was to investigate how the ball position along the mediolateral (M-L) direction of a golfer causes a chain effect in the ground reaction force, body segment and joint angles, and whole-body centre of mass during the golf swing. Twenty professional golfers were asked to complete five straight shots for each 5 different ball positions along M-L: 4.27 cm (ball diameter), 2.14 cm (ball radius), 0 cm (reference position at preferred ball position), – 2.14 cm, and – 4.27 cm, while their ground reaction force and body segment motions were captured. The dependant variables were calculated at 14 swing events from address to impact, and the differences between the ball positions were evaluated using Statistical Parametric Mapping. The left-sided ball positions at address showed a greater weight distribution on the left foot with a more open shoulder angle compared to the reference ball position, whereas the trend was reversed for the right-sided ball positions. These trends disappeared during the backswing and reappeared during the downswing. The whole-body centre of mass was also located towards the target for the left-sided ball positions throughout the golf swing compared to the reference ball position, whereas the trend was reversed for the right-sided ball positions. We have concluded that initial ball position at address can cause a series of chain effects throughout the golf swing.

scholarly journals Endoscopic removal of metal foreign bodies by magnet: case report

2020 ◽  
Vol 10 (4) ◽  
pp. 467-472
Author(s):  
Vladimir I. Petlakh ◽  
Vladimir A. Borovitsky ◽  
Alexander K. Konovalov ◽  
Natalya N. Strogova
Keyword(s):  
Case Report ◽  
Conservative Therapy ◽  
Foreign Bodies ◽  
Intestinal Wall ◽  
The Body ◽  
Surgical Interventions ◽  
Number Of Children ◽  
The Past ◽  
A Chain ◽  
The Right

The number of children swallowing magnetic foreign bodies has been a significantly high for the past decades, increasingly needing endoscopic or surgical interventions. Case report. In our observation, a 12-year-old girl swallowed magnetic balls from childrens designer 10 days prior to hospital admission. Foreign bodies (5 balls) were found during X-ray examination in the projection of the cecum. Conservative therapy carried out for 4 days had no success, thus colonoscopy was performed to remove foreign bodies. Foreign bodies were fixed to the intestinal wall, and attempts to separate them were unsuccessful. When a medical magnet was placed outside the body in the right iliac region, a chain of magnetic balls detached from the intestinal wall and made it possible to be captured in a trap loop and be removed. The girl avoided a laparotomy with an opening of the colon. Conclusion. External use of a medical magnet is effective for navigation and assistance during colonoscopic extraction when magnetic foreign bodies are found in the colon.

scholarly journals Consent by GDPR vs. Blockchain

2020 ◽  
Vol 12 (1) ◽  
pp. 149-166
Author(s):  
Bruno Moslavac
Keyword(s):  
Comparative Method ◽  
Personal Data ◽  
Daily Lives ◽  
Personal Data Protection ◽  
Blockchain Technology ◽  
Explicit Consent ◽  
Data Processor ◽  
On Line ◽  
A Chain ◽  
The Right

The role of consent in personal data protection today is probably the first question for researches on how it impacts in our daily lives, ordinarily or on-line. This paper uses comparative method analyzes seemingly opposed essential parts of consent due to lawfulness of personal data processing versus inclusion of same data in a chain using blockchain technology, with the hypothesis that freewill public announcement of personal data substitute explicit consent for their processing. Finally, the author concludes that the principle of lawfulness stated by GDPR is not violated if the personal data processor using blockchain technology does not obtain consent for the processing of personal data, voluntarily put into the chain by another subject in the same “chain” and the “right to be forgotten” isn’t absolute right.

scholarly journals An MEG Study of Picture Naming

1998 ◽  
Vol 10 (5) ◽  
pp. 553-567 ◽  
Author(s):  
Willem J. M. Levelt ◽  
Peter Praamstra ◽  
Antje S. Meyer ◽  
Päivi Helenius ◽  
Riitta Salmelin
Keyword(s):  
Picture Naming ◽  
Time Windows ◽  
Naming Latency ◽  
Cortical Activation ◽  
Response Patterns ◽  
Phonological Encoding ◽  
A Chain ◽  
Wernicke’S Area ◽  
The Individual ◽  
The Right

The purpose of this study was to relate a psycholinguistic processing model of picture naming to the dynamics of cortical activation during picture naming. The activation was recorded from eight Dutch subjects with a whole-head neuromagnetometer. The processing model, based on extensive naming latency studies, is a stage model. In preparing a picture's name, the speaker performs a chain of specific operations. They are, in this order, computing the visual percept, activating an appropriate lexical concept, selecting the target word from the mental lexicon, phonological encoding, phonetic encoding, and initiation of articulation. The time windows for each of these operations are reasonably well known and could be related to the peak activity of dipole sources in the individual magnetic response patterns. The analyses showed a clear progression over these time windows from early occipital activation, via parietal and temporal to frontal activation. The major specific findings were that (1) a region in the left posterior temporal lobe, agreeing with the location of Wernicke's area, showed prominent activation starting about 200 msec after picture onset and peaking at about 350 msec, (i.e., within the stage of phonological encoding), and (2) a consistent activation was found in the right parietal cortex, peaking at about 230 msec after picture onset, thus preceding and partly overlapping with the left temporal response. An interpretation in terms of the management of visual attention is proposed.

Introduction

2018 ◽  
pp. 1-27
Author(s):  
Anushka Singh
Keyword(s):  
Free Speech ◽  
Hate Speech ◽  
Freedom Of Expression ◽  
University Of California ◽  
American Democracy ◽  
Mob Violence ◽  
A Chain ◽  
The Right ◽  
The University ◽  
Public Lecture

On 1 February 2017 at the University of California, Berkeley, USA, mob violence erupted on campus with 1,500 protesters demanding the cancellation of a public lecture by Milo Yiannopoulos, a British author notorious for his alleged racist and anti-Islamic views.1 Consequently, the event was cancelled triggering a chain of reactions on the desirability and limits of freedom of expression within American democracy. The Left-leaning intellectuals and politicians were accused of allowing the mob violence to become a riot on campus defending it in the name of protest against racism, fascism, and social injustice. In defending the rights of the protesters to not allow ‘illiberal’ or hate speech on campus, however, many claimed that the message conveyed was that only liberals had the right to free speech....

scholarly journals AN INVARIANT OF LEGENDRIAN AND TRANSVERSE LINKS FROM OPEN BOOK DECOMPOSITIONS OF CONTACT 3-MANIFOLDS

2020 ◽  
pp. 1-33
Author(s):  
ALBERTO CAVALLO
Keyword(s):  
Chain Complex ◽  
Open Book ◽  
Rational Homology ◽  
Open Book Decompositions ◽  
Chain Complexes ◽  
Legendrian Links ◽  
Sum Formula ◽  
A Chain ◽  
Special Cycle ◽  
Rational Homology Sphere

Abstract We introduce a generalization of the Lisca–Ozsváth–Stipsicz–Szabó Legendrian invariant ${\mathfrak L}$ to links in every rational homology sphere, using the collapsed version of link Floer homology. We represent a Legendrian link L in a contact 3-manifold ${(M,\xi)}$ with a diagram D, given by an open book decomposition of ${(M,\xi)}$ adapted to L, and we construct a chain complex ${cCFL^-(D)}$ with a special cycle in it denoted by ${\mathfrak L(D)}$ . Then, given two diagrams ${D_1}$ and ${D_2}$ which represent Legendrian isotopic links, we prove that there is a map between the corresponding chain complexes that induces an isomorphism in homology and sends ${\mathfrak L(D_1)}$ into ${\mathfrak L(D_2)}$ . Moreover, a connected sum formula is also proved and we use it to give some applications about non-loose Legendrian links; that are links such that the restriction of ${\xi}$ on their complement is tight.

scholarly journals Synthesis, Crystal Structure, and N2-Adsorption Property of a Chain Complex of Rhodium(II) Benzoate and Piperazine

2013 ◽  
Vol 29 (0) ◽  
pp. 21-22 ◽  
Author(s):  
Masahiro MIKURIYA ◽  
Kazuya OUCHI ◽  
Yasutaka NAKANISHI ◽  
Daisuke YOSHIOKA ◽  
Hidekazu TANAKA ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Adsorption Property ◽  
Chain Complex ◽  
N2 Adsorption ◽  
A Chain

Abstract Concept Instantiation with Context Relevance Measurement

2020 ◽  
Author(s):  
Shengwei Gu ◽  
Xiangfeng Luo ◽  
Hao Wang ◽  
Jing Huang ◽  
Subin Huang
Keyword(s):  
Web Search ◽  
False Negative ◽  
Model Performance ◽  
Category Structure ◽  
Abstract Concept ◽  
Contextual Constraint ◽  
Proposed Model ◽  
The Right ◽  
Novel Model ◽  
Walk Algorithm

In different contexts, one abstract concept (e.g., fruit) may be mapped into different concrete instance sets, which is called abstract concept instantiation. It has been widely applied in many applications, such as web search, intelligent recommendation, etc. However, in most abstract concept instantiation models have the following problems: (1) the neglect of incorrect label and label incompleteness in the category structure on which instance selection relies; (2) the subjective design of instance profile for calculating the relevance between instance and contextual constraint. The above problems lead to false prediction in terms of abstract concept instantiation. To tackle these problems, we proposed a novel model to instantiate the abstract concept. Firstly, to alleviate the incorrect label and remedy label incompleteness in the category structure, an improved random-walk algorithm is proposed, called InstanceRank, which not only utilize the category information, but it also exploits the association information to infer the right instances of an abstract concept. Secondly, for better measuring the relevance between instances and contextual constraint, we learn the proper instance profile from different granularity ones. They are designed based on the surrounding text of the instance. Finally, noise reduction and instance filtering are introduced to further enhance the model performance. Experiments on Chinese food abstract concept set show that the proposed model can effectively reduce false positive and false negative of instantiation results.

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