natural extension
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2022 ◽  
Vol 55 (1) ◽  
Author(s):  
Jaimie Greasley ◽  
Shivan Goolcharan ◽  
Roger Andrews

In the twin-island state of Trinidad and Tobago, urinary stone analysis is not routinely performed. This study investigates, via powder X-ray diffraction, 52 urinary tract calculi collected from hospitals in Trinidad. Of these, 46 stones were analysed with Rietveld refinement for quantitative analysis and materials characterization. Refined unit-cell, microstructural and weight fraction parameters were obtained, with the last being used for stone classification. The results revealed seven distinct mineralogical phases of varying frequency: calcium oxalate monohydrate (COM, 58%), calcium oxalate dihydrate (COD, 23%), carbonated apatite (APA, 48%), brushite (BRU, 6%), struvite (STR, 42%), uric acid (UA, 23%) and ammonium acid urate (AAU, 19%). The average refined crystallite sizes were 1352 ± 90 Å (COM), 1921 ± 285 Å (COD), 83 ± 5 Å (APA), 1172 ± 9 Å (BRU), 1843 ± 138 Å (STR), 981 ± 87 Å (UA) and 292 ± 83 Å (AAU). Subsequently, 36.5% of stones were categorized as phosphates, 34.6% as oxalates, 13.5% as uric acid/urates and 15.4% as mixed compositions. The study findings highlight the importance of stone analysis as a necessary step towards disease management of local patients, and endorse the application of Rietveld refinement as a natural extension to diffraction-based kidney stone investigations.


2022 ◽  
Vol 2022 (1) ◽  
Author(s):  
Mawardi Bahri

AbstractThe windowed linear canonical transform is a natural extension of the classical windowed Fourier transform using the linear canonical transform. In the current work, we first remind the reader about the relation between the windowed linear canonical transform and windowed Fourier transform. It is shown that useful relation enables us to provide different proofs of some properties of the windowed linear canonical transform, such as the orthogonality relation, inversion theorem, and complex conjugation. Lastly, we demonstrate some new results concerning several generalizations of the uncertainty principles associated with this transformation.


2022 ◽  
Vol 355 ◽  
pp. 02001
Author(s):  
Lan Luo ◽  
Jingsong Leng ◽  
Tingting Xie

The concept of g-frame is a natural extension of the frame. This article mainly discusses the relationship between some special bounded linear operators and g-frames, and characterizes the properties of g-frames. In addition, according to the operator spectrum theory, the eigenvalues are introduced into the g-frame theory, and a new expression of the best frame boundary of the g-frame is given.


2022 ◽  
Vol 0 (0) ◽  
pp. 0
Author(s):  
Victor Vargas

<p style='text-indent:20px;'>Consider <inline-formula><tex-math id="M2">\begin{document}$ \beta &gt; 1 $\end{document}</tex-math></inline-formula> and <inline-formula><tex-math id="M3">\begin{document}$ \lfloor \beta \rfloor $\end{document}</tex-math></inline-formula> its integer part. It is widely known that any real number <inline-formula><tex-math id="M4">\begin{document}$ \alpha \in \Bigl[0, \frac{\lfloor \beta \rfloor}{\beta - 1}\Bigr] $\end{document}</tex-math></inline-formula> can be represented in base <inline-formula><tex-math id="M5">\begin{document}$ \beta $\end{document}</tex-math></inline-formula> using a development in series of the form <inline-formula><tex-math id="M6">\begin{document}$ \alpha = \sum_{n = 1}^\infty x_n\beta^{-n} $\end{document}</tex-math></inline-formula>, where <inline-formula><tex-math id="M7">\begin{document}$ x = (x_n)_{n \geq 1} $\end{document}</tex-math></inline-formula> is a sequence taking values into the alphabet <inline-formula><tex-math id="M8">\begin{document}$ \{0,\; ...\; ,\; \lfloor \beta \rfloor\} $\end{document}</tex-math></inline-formula>. The so called <inline-formula><tex-math id="M9">\begin{document}$ \beta $\end{document}</tex-math></inline-formula>-shift, denoted by <inline-formula><tex-math id="M10">\begin{document}$ \Sigma_\beta $\end{document}</tex-math></inline-formula>, is given as the set of sequences such that all their iterates by the shift map are less than or equal to the quasi-greedy <inline-formula><tex-math id="M11">\begin{document}$ \beta $\end{document}</tex-math></inline-formula>-expansion of <inline-formula><tex-math id="M12">\begin{document}$ 1 $\end{document}</tex-math></inline-formula>. Fixing a Hölder continuous potential <inline-formula><tex-math id="M13">\begin{document}$ A $\end{document}</tex-math></inline-formula>, we show an explicit expression for the main eigenfunction of the Ruelle operator <inline-formula><tex-math id="M14">\begin{document}$ \psi_A $\end{document}</tex-math></inline-formula>, in order to obtain a natural extension to the bilateral <inline-formula><tex-math id="M15">\begin{document}$ \beta $\end{document}</tex-math></inline-formula>-shift of its corresponding Gibbs state <inline-formula><tex-math id="M16">\begin{document}$ \mu_A $\end{document}</tex-math></inline-formula>. Our main goal here is to prove a first level large deviations principle for the family <inline-formula><tex-math id="M17">\begin{document}$ (\mu_{tA})_{t&gt;1} $\end{document}</tex-math></inline-formula> with a rate function <inline-formula><tex-math id="M18">\begin{document}$ I $\end{document}</tex-math></inline-formula> attaining its maximum value on the union of the supports of all the maximizing measures of <inline-formula><tex-math id="M19">\begin{document}$ A $\end{document}</tex-math></inline-formula>. The above is proved through a technique using the representation of <inline-formula><tex-math id="M20">\begin{document}$ \Sigma_\beta $\end{document}</tex-math></inline-formula> and its bilateral extension <inline-formula><tex-math id="M21">\begin{document}$ \widehat{\Sigma_\beta} $\end{document}</tex-math></inline-formula> in terms of the quasi-greedy <inline-formula><tex-math id="M22">\begin{document}$ \beta $\end{document}</tex-math></inline-formula>-expansion of <inline-formula><tex-math id="M23">\begin{document}$ 1 $\end{document}</tex-math></inline-formula> and the so called involution kernel associated to the potential <inline-formula><tex-math id="M24">\begin{document}$ A $\end{document}</tex-math></inline-formula>.</p>


2021 ◽  
Vol 10 (2) ◽  
pp. 104-119
Author(s):  
Stéphane Hadjeras

FR. A la veille de la Grande Guerre la boxe anglaise a pris, dans les sociétés anglo-saxonnes (États-Unis, Grande-Bretagne et Australie) et depuis peu en France, une dimension sociale et culturelle d’importance. Dans l’Hexagone alors qu’elle était au tournant du XIXème siècle une mise en scène illégale et inconnue du grand public, elle a connu en 10 ans une fulgurante ascension. Aussi, En 1914, elle est devenue sport roi non seulement à Paris mais également en province. Ce que l’on peut appeler « la Belle Époque de la boxe anglaise en France » est marqué par une corrélation entre les succès de cette pratique et l’avènement de la première superstar du sport tricolore : le boxeur Georges Carpentier. Né en 1894 à Liévin, dans les bassins miniers du Pas-de-Calais, le « gosse » embrasse la carrière de pugiliste à l’âge de 14 ans. Entre 1908 et 1914, au rythme de nombreuses et surprenantes victoires, sa popularité ne cesse de croître. Elle atteint son apogée dans les deux années précédant la guerre, particulièrement lors de probants triomphes face à la fine fleur pugilistique britannique. A l’occasion de matchs mobilisant les ressorts du nationalisme anti-anglais, ces affrontements poursuivent la longue inimitié historique entre la France et la « perfide Albion », tout en nourrissant et amplifiant la célébrité du jeune prodige. A l’aube du culte des vedettes et dans une métaphore évidente de la guerre, la presse franco-britannique n’hésite pas à l’élever au rang de « vengeur de Waterloo ». Puis, contre toute attente, à quelques mois de l’embrasement de la vieille Europe, augurant du nouveau jeu d’alliance militaire qui se dessine dans les salons de la diplomatie franco-anglaise, il devient dans ces mêmes journaux le « champion de l’Entente Cordiale ». *** EN. In the years preceding the Great War, English boxing occupied an important social and cultural role in Anglo-Saxon societies (United States, Great Britain and Australia) and came to gradually occupy a similar position in France. At the turn of the 19th century, it was still an illegal and obscure show to French audiences. However, in the course of the following decade, it was propelled to higher grounds: by 1914, it had become the king of sports, both in Paris and in the provinces. The “Belle Époque of English boxing in France" is characterized by the correlation between the success of the sport and the rise of the first French boxing superstar, Georges Carpentier. Born in 1894 in Liévin, in the coal mining basins of the Pas-de-Calais, the “kid” embraces the career of pugilist at the age of 14. Between 1908 and 1914, his popularity was on a constant rise thanks to numerous and surprising victories. His popularity climaxes in the two years preceding the war, largely thanks to multiple victories against the British pugilistic elite. Mobilizing nationalism fueled by anti-English sentiments, these boxing matches are presented as a natural extension of the long historical enmity between France and the "perfidious Albion", contributing to grow and amplify the young prodigy’s fame. At the dawn of celebrity worship, and in an obvious metaphor of the war, the Franco-British press did not hesitate to adorn him as the "Waterloo avenger". Then, against all odds, a few months before the dislocation of old Europe, the same newspapers transformed him into the "champion” of the Entente Cordiale, implicitly pulling in behind the new military alliances taking shape in the halls of Franco-British diplomacy. *** PT. Às vésperas da Grande Guerra, o boxe inglês assume uma dimensão sociocultural central nas sociedades anglo-saxônicas (Estados Unidos, Grã-Bretanha e Austrália). Isso ocorre também na França, onde, até a virada do século XIX, não passava de uma encenação ilegal desconhecida do público em geral. 10 anos depois, experimenta uma ascensão meteórica, tornando-se, em 1914, o rei dos esportes em Paris, mas também nas demais cidades francesas. O período da Belle Époque do boxe inglês na França é marcado por uma convergência entre o sucesso do boxe e o advento da primeira superestrela do esporte francês: o boxeador Georges Carpentier. Nascido em 1894 em Liévin, nas bacias mineiras do Pas-de-Calais, o “moleque”, como era chamado, abraçou a carreira de pugilista aos 14 anos de idade. Entre 1908 e 1914, tendo já acumulado diversas vitórias surpreendentes, sua popularidade não para de crescer, atingindo seu auge nos dois anos que precederam a guerra, com vitórias arrasadoras contra a nata do pugilismo britânico. Essas partidas, cenário de incitação ao nacionalismo antiinglês, passaram simultaneamente a consolidar a longa inimizade histórica entre a França e o “pérfido Albion” e a fama do jovem prodígio. Nos primórdios do culto às estrelas do esporte, a imprensa franco-britânica, lançando mão de uma óbvia metáfora bélica, eleva Carpentier ao ranking de “vingador de Waterloo”. Poucos meses antes do estremecimento da velha Europa, contrariando todas as expectativas e prefigurando o novo jogo de alianças militares que se perfilava nos salões da diplomacia franco-britânica, Georges Carpentier torna-se, nas colunas desses mesmos jornais, o “campeão da Entente Cordiale”. ***


Cells ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 3579
Author(s):  
Yuxin Wang ◽  
Thomas W. Carion ◽  
Abdul Shukkur Ebrahim ◽  
Gabriel Sosne ◽  
Elizabeth A. Berger

Previous work examining the therapeutic efficacy of adjunct thymosin beta 4 (Tβ4) to ciprofloxacin for ocular infectious disease has revealed markedly reduced inflammation (inflammatory mediators and innate immune cells) with increased activation of wound healing pathways. Understanding the therapeutic mechanisms of action have further revealed a synergistic effect with ciprofloxacin to enhance bacterial killing along with a regulatory influence over macrophage effector cell function. As a natural extension of the aforementioned work, the current study uses an experimental model of P. aeruginosa-induced keratitis to examine the influence of Tβ4 regarding polymorphonuclear leukocyte (PMN/neutrophil) cellular function, contributing to improved disease response. Flow cytometry was utilized to phenotypically profile infiltrating PMNs after infection. The generation of reactive oxygen species (ROS), neutrophil extracellular traps (NETs), and PMN apoptosis were investigated to assess the functional activities of PMNs in response to Tβ4 therapy. In vitro work using peritoneal-derived PMNs was similarly carried out to verify and extend our in vivo findings. The results indicate that the numbers of infiltrated PMNs into infected corneas were significantly reduced with adjunctive Tβ4 treatment. This was paired with the downregulated expression of proinflammatory markers on these cells, as well. Data generated from PMN functional studies suggested that the corneas of adjunctive Tβ4 treated B6 mice exhibit a well-regulated production of ROS, NETs, and limited PMN apoptosis. In addition to confirming the in vivo results, the in vitro findings also demonstrated that neutrophil elastase (NE) was unnecessary for NETosis. Collectively, these data provide additional evidence that adjunctive Tβ4 + ciprofloxacin treatment is a promising option for bacterial keratitis that addresses both the infectious pathogen and cellular-mediated immune response, as revealed by the current study.


2021 ◽  
Vol 7 (12) ◽  
pp. 277
Author(s):  
Ivan Galyaev ◽  
Alexey Mashtakov

We consider a natural extension of the Petitot–Citti–Sarti model of the primary visual cortex. In the extended model, the curvature of contours is taken into account. The occluded contours are completed via sub-Riemannian geodesics in the four-dimensional space M of positions, orientations, and curvatures. Here, M=R2×SO(2)×R models the configuration space of neurons of the visual cortex. We study the problem of sub-Riemannian geodesics on M via methods of geometric control theory. We prove complete controllability of the system and the existence of optimal controls. By application of the Pontryagin maximum principle, we derive a Hamiltonian system that describes the geodesics. We obtain the explicit parametrization of abnormal extremals. In the normal case, we provide three functionally independent first integrals. Numerical simulations indicate the existence of one more first integral that results in Liouville integrability of the system.


Author(s):  
Yang ying ◽  
Shu Xiao ◽  
Huaixin Cao

Abstract The correlations in quantum networks have attracted strong interest due to the fact that linear Bell inequalities derived from one source are useless for characterizing multipartite correlations of general quantum networks. In this paper, { a type of multi-star-shaped quantum networks are introduced and discussed. Such a network consists of three-grade nodes: the first grade is named party (node) $A$, the second one consists of $m$ nodes marked $B^1,B^2,\ldots,B^m$, which are stars of $A$ and the third one consists of $m^2$ nodes $C^j_k (j,k=1,2,\ldots,m)$, where $C^j_k (k=1,2,\ldots,m)$ are stars of $B^j$. We call such a network a $3$-grade $m$-star quantum network and denoted by $SQN(3,m)$, being as a natural extension of bilocal networks and star-shaped networks.} We introduce and discussed the locality and strong locality of a $SQN(3,m)$ and derive the related nonlinear Bell inequalities, called $(3,m)$-locality inequalities and $(3,m)$-strong locality inequalities. To compare with the bipartite locality of quantum states, we define the separability of $SQN(3,m)$ that imply the locality and then locality of $SQN(3,m)$. When all of the shared states of the network are pure ones, we prove that $SQN(3,m)$ is nonlocal if and only if it is entangled.


2021 ◽  
Vol 157 (12) ◽  
pp. 2657-2698
Author(s):  
Runlin Zhang

In the present article, we study the following problem. Let $\boldsymbol {G}$ be a linear algebraic group over $\mathbb {Q}$ , let $\Gamma$ be an arithmetic lattice, and let $\boldsymbol {H}$ be an observable $\mathbb {Q}$ -subgroup. There is a $H$ -invariant measure $\mu _H$ supported on the closed submanifold $H\Gamma /\Gamma$ . Given a sequence $(g_n)$ in $G$ , we study the limiting behavior of $(g_n)_*\mu _H$ under the weak- $*$ topology. In the non-divergent case, we give a rather complete classification. We further supplement this by giving a criterion of non-divergence and prove non-divergence for arbitrary sequence $(g_n)$ for certain large $\boldsymbol {H}$ . We also discuss some examples and applications of our result. This work can be viewed as a natural extension of the work of Eskin–Mozes–Shah and Shapira–Zheng.


2021 ◽  
Author(s):  
◽  
Ted Thomas

<p>Virtual teams are a growing response to increased de-centralisation and globalization, and the need for organizations to adapt to an ever changing and complex work environment. Their growing prevalence reflects many different factors, including the increased global reach of many organizations, changing workforce demographics, and heightened competitive pressures requiring greater organizational flexibility and responsiveness.  This phenomenon has grown rapidly in recent years through advancements and greater access to technologies for communication and collaboration.  Organizations however are being challenged with understanding what makes these virtual teams effective and how to measure the achievement of such effectiveness. Combined with the convergence of telephony and data technologies this has enabled voice and video to be delivered ‘on demand’ at a far more affordable price to the end consumer. With the added dynamic of ‘mobile’ becoming such a pervasive technology, this is providing the fuel driving the establishment of greater numbers of virtual teams. We now live in an increasingly “connected world” and with the blurring of work and leisure time, for many, virtual teams have already or are becoming a natural extension of the workplace.  Individuals are demanding personal flexibility in the management of their time and space and this is matched by organizations seeking flexibility to scale resources in meeting changing demand. Virtual teams may also be seen as a response to satisfying changing social and organizational aspirations.  A range of factors are seen as contributing to the effectiveness of virtual teams and these include technology, trust, sharing of knowledge, empowerment and leadership. This study focuses on trust as a primary factor in achieving virtual team effectiveness, and assesses the significance of trust and the sharing of knowledge amongst team members.  Trust determines how people work together, listen to one another, and build effective relationships. When people believe that they are working for trustworthy organizations, they are willing to invest their time and talents in making a difference in an organization. People who feel more connected will invest more of themselves in their work. High trust levels lead to a greater sense of self responsibility, greater interpersonal insight, and more collective action toward achieving common goals.  However, with a lack of face-to-face contact, trust based on performance substitutes for trust based on social interaction.  Trust is a cornerstone to achieving virtual team effectiveness and from an organizational perspective this highlights the need for regular communication with team members to reinforce the culture and values of the organization.  In the age of the knowledge economy, knowledge is seen as a critical resource for competitive advantage. The willingness of team members to share knowledge with others on the team can be attributed to the strength of the trust relationship and this further enhances virtual team effectiveness.  The challenges for organizations are to understand what level of trust exists across the team, how this impacts on team effectiveness and to be able to apply interventions when seeking to increase team effectiveness.  Active and regular communications programmes, internal marketing campaigns and short surveys are approaches for developing and enhancing the trust relationship. Organizations that are unwilling or unable to use virtual teams may find themselves losing out in an increasingly competitive and rapidly changing global economic and social environment. The technology and communication advances are clear, yet enabling effective participation and team collaboration is a more complex problem.</p>


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