scholarly journals NON-ARCHIMEDEAN YOMDIN–GROMOV PARAMETRIZATIONS AND POINTS OF BOUNDED HEIGHT

2015 ◽  
Vol 3 ◽  
Author(s):  
RAF CLUCKERS ◽  
GEORGES COMTE ◽  
FRANÇOIS LOESER

We prove an analog of the Yomdin–Gromov lemma for $p$-adic definable sets and more broadly in a non-Archimedean definable context. This analog keeps track of piecewise approximation by Taylor polynomials, a nontrivial aspect in the totally disconnected case. We apply this result to bound the number of rational points of bounded height on the transcendental part of $p$-adic subanalytic sets, and to bound the dimension of the set of complex polynomials of bounded degree lying on an algebraic variety defined over $\mathbb{C}(\!(t)\!)$, in analogy to results by Pila and Wilkie, and by Bombieri and Pila, respectively. Along the way we prove, for definable functions in a general context of non-Archimedean geometry, that local Lipschitz continuity implies piecewise global Lipschitz continuity.

2017 ◽  
Vol 82 (1) ◽  
pp. 120-136 ◽  
Author(s):  
LUCK DARNIÈRE ◽  
IMMANUEL HALPUCZOK

AbstractWe prove that forp-optimal fields (a very large subclass ofp-minimal fields containing all the known examples) a cell decomposition theorem follows from methods going back to Denef’s paper [7]. We derive from it the existence of definable Skolem functions and strongp-minimality. Then we turn to stronglyp-minimal fields satisfying the Extreme Value Property—a property which in particular holds in fields which are elementarily equivalent to ap-adic one. For such fieldsK, we prove that every definable subset ofK×Kdwhose fibers overKare inverse images by the valuation of subsets of the value group is semialgebraic. Combining the two we get a preparation theorem for definable functions onp-optimal fields satisfying the Extreme Value Property, from which it follows that infinite sets definable over such fields are in definable bijection iff they have the same dimension.


2017 ◽  
Vol 18 (06) ◽  
pp. 1157-1213
Author(s):  
Piotr Kowalski

We prove a positive characteristic version of Ax’s theorem on the intersection of an algebraic subvariety and an analytic subgroup of an algebraic group [Ax, Some topics in differential algebraic geometry. I. Analytic subgroups of algebraic groups, Amer. J. Math. 94 (1972), 1195–1204]. Our result is stated in a more general context of a formal map between an algebraic variety and an algebraic group. We derive transcendence results of Ax–Schanuel type.


2012 ◽  
Vol 77 (2) ◽  
pp. 621-630 ◽  
Author(s):  
Raf Cluckers ◽  
Eva Leenknegt

AbstractWe introduce a very weak language on p-adic fields K, which is just rich enough to have exactly the same definable subsets of the line K that one has using the ring language. (In our context, definable always means definable with parameters.) We prove that the only definable functions in the language are trivial functions. We also give a definitional expansion of in which K has quantifier elimination, and we obtain a cell decomposition result for -definable sets.Our language can serve as a p-adic analogue of the very weak language (<) on the real numbers, to define a notion of minimality on the field of p-adic numbers and on related valued fields. These fields are not necessarily Henselian and may have positive characteristic.


2020 ◽  
pp. 66-92 ◽  
Author(s):  
A. E. Abramov ◽  
A. D. Radygin ◽  
M. I. Chernova ◽  
R. M. Entov

This article analyzes the key patterns of the dividend policy and the problem of the “dividend puzzle” in the general context of the development of the stock market in Russia. The article consists of two parts.In the first part we summarize main research trends of dividend policy in modern economic theory (the classical Modigliani—Miller theory of dividend irrelevance, agent and signal hypotheses, the smoothing model, the catering theory, etc.). We emphasize the theoretical analysis of motivation of the largest Russian companies for profit allocation and dividend payout, based on a sample of 236 joint stock companies. Since 2012, a steady increase in dividend payments has been revealed in both private and state-owned enterprises (SOEs). The bulk of dividend payments from SOEs accounts for only 12 major companies. Along with an increase in the market value, dividends have become an important factor in the total return on shares. Under current conditions, the probability of paying dividends depends not only on the size of the company and indicators of its’ financial stability, but also on the presence of the state in the capital of companies. However, the relationship between the probability of paying dividends and state participation in the ownership structure is not universal and can be explained by specific factors that go beyond the classical dividend theories.In the second part we will analyze the patterns of stock market performance and dividend policy of the largest Russian companies, motivation for dividend payouts and special aspects of SOEs policy.


Author(s):  
Ehud Hrushovski ◽  
François Loeser

This chapter provides some background material on definable sets, definable types, orthogonality to a definable set, and stable domination, especially in the valued field context. It considers more specifically these concepts in the framework of the theory ACVF of algebraically closed valued fields and describes the definable types concentrating on a stable definable V as an ind-definable set. It also proves a key result that demonstrates definable types as integrals of stably dominated types along some definable type on the value group sort. Finally, it discusses the notion of pseudo-Galois coverings. Every nonempty definable set over an algebraically closed substructure of a model of ACVF extends to a definable type.


2016 ◽  
pp. 15
Author(s):  
Mariana Giaretto ◽  
Victoria Naffa

ResumenEn este trabajo analizamos las relaciones entre tomas de tierras y Estado, en elAlto Valle de Río Negro en Argentina. En un contexto general de especulacióninmobiliaria, por la que se encarecen los precios de alquileres y terrenos, y depolíticas de vivienda selectivas y acotadas, los sectores populares acceden aun espacio en la ciudad mediante tomas de tierras. Frente a estos conflictos,el Estado, en sus diferentes niveles y poderes, despliega una forma deintervención basada en la criminalización de las luchas por tierra y vivienda.Al mismo tiempo, el poder ejecutivo nacional crea la Secretaría de Acceso alHábitat, para posibilitar la intervención política orientada a la regularizaciónde los asentamientos. Sin embargo, esta intervención tiende a reinscribir laproblemática habitacional en el campo político, para reducirla a un conflicto“entre partes”, eludiendo la responsabilidad estatal.Desde un enfoque metodológico cualitativo, seleccionamos como referenteempírico el caso del asentamiento de Villa Obrera en Fiske, Menuco (Gral.Roca), y las técnicas de recolección de datos se basan en fuentes secundarias,como expedientes judiciales y normativa, y en fuentes primarias como son losrelatos de los protagonistas mediante entrevistas individuales y colectivas.Palabras clave: tomas de tierras, Estado, criminalización de los conflictos.Conflicts caused by land occupation and modesof State intervention: analysis of an experience ofAlto Valle in Río Negro (Argentina)AbstractThis paper analyzes the relationship between State and land occupation,at Alto Valle in Río Negro, Argentina. In a general context of real estatespeculation, where rents and land prices are expensive, and a policy ofselective and limited housing, popular sectors can have access to a spacein the city through land occupation. In front of these conflicts, the Statein its different levels and powers, displays a form of intervention basedon the criminalization of struggles for land and housing. At the sametime, the national executive creates the Secretariat of Access to Habitat,oriented to allow political intervention for the regularization of settlements.However, this intervention tends to re-register the housing problems in thepolitical arena, reducing it to a conflict “between parties” and eluding theresponsibility of the State.From a qualitative methodological approach, we selected as empirical referencethe case of the settlement of Villa Obrera in Fiske, Menuco (GeneralRoca). The techniques of data collection are based on secondary sources, suchas policy and legal records, and primary sources as the stories of protagoniststhrough individual and collective interviews.Keywords: land occupation, State, criminalization of conflicts.Conflitos sobre ocupações de terras e modos deintervenção do estado: análise de uma experiênciado Alto Valle do Rio Preto (Argentina)ResumoEste trabalho analisa as relações entre a posse de terra e o Estado, no AltoValle do Rio Preto, na Argentina. Num contexto geral da especulaçãoimobiliária, por qual se encarecem os preços do aluguel e das terras, e depolíticas de habitação seletivas e limitadas, os setores populares acedem aum espaço na cidade através de ocupações de terras. Frente a estes conflitos,o Estado, em seus diferentes níveis e poderes, desenvolve uma forma deintervenção com base na criminalização das lutas pela terra e vivenda. Aomesmo tempo, o poder executivo nacional cria a Secretaria de Acesso àHabitat para possibilitar à intervenção política orientada a regularização dosassentamentos. No entanto, esta intervenção tende a registrar os problemasde habitação no campo político, para reduzi-la a um conflito “entre aspartes”, iludindo a responsabilidade do Estado.A partir de uma abordagem metodológica qualitativa, foi selecionado comoreferência empírica o caso do Assentamento de Villa Obrera em Fiske,Menuco (Gral. Roca), e as técnicas de recolecção de dados são baseados emfontes secundárias, como expedientes judiciais e normativos, e em fontes primárias como são as histórias dos protagonistas através de entrevistasindividuais e coletivas.Palavras-chave: tomada de terras, Estado, criminalização dos conflitos.


2020 ◽  
Author(s):  
Akihiko Ozaki ◽  
Yosuke Onoue ◽  
Anju Murayama ◽  
Taishi Tahara ◽  
Yuki Senoo ◽  
...  

BACKGROUND Rural physician undersupply is a universal concern, leading to sudden physician absenteeism or unavailability on occasion. While media and social networking services may help mitigate these emergencies, information is lacking about their actual contribution in times of physician absenteeism. On December 30, 2016, the director and sole physician of Takano Hospital in Fukushima, Japan, died. The physician’s passing placed many hospitalized patients in danger. This sudden case of physician unavailability, named the Takano Hospital Crisis, provoked massive attention from the general public, in the media and on social media networks such as Twitter. OBJECTIVE The aim of this study was to analyze newspaper articles, tweets and Twitter accounts relating to Takano Hospital Crisis. METHODS Newspaper articles and tweets were searched for keywords associated with Takano Hospital Crisis and its former director between October 2016 and June 2017. We first evaluated the chronological change in the number of articles and tweets, and the number of characters and relevant keywords in the articles. Then tweets and influencers who were popular on the Twitter platform from December 30, 2016 to February 28, 2017, were categorized. RESULTS We assessed 151 newspaper articles and 67,006 tweets. The results show that number of newspaper articles and tweets steeply increased and then diminished within the first month of the incident. The median number of characters in newspapers articles was 436 and the most frequent keyword was medical doctor. There were 753 original tweets that were retweeted more than four times from December 30, 2016 to February 28, 2017. Of these, 245 (32.5%) expressed concern. Notable influencers were journalists, news media outlets, and healthcare professionals that helped with fund raising and providing clinical service in the hospital. CONCLUSIONS Twitter could temporarily function in cases of sudden physician absenteeism to attract volunteers and funding, however, this would not be a long-term solution. In a more general context, a long-term effort of supports from the hospitals themselves and the government will be required to manage the persistent state of physician absenteeism.


Author(s):  
Jacob Stegenga

There are three methodological challenges to measuring the effectiveness of medical interventions: the choice of good measuring instruments, the use of appropriate analytic measures, and the use of a reliable method of extrapolating measures from an experimental context to a more general context. In practice each of these challenges contributes to overestimating the effectiveness of medical interventions. These challenges suggest corrective principles. The instruments employed in clinical research should measure patient-relevant and disease-specific parameters. Effectiveness always should be measured and reported using absolute outcome measures (such as ‘risk difference’), and we should employ caution when interpreting relative outcome measures (such as ‘relative risk reduction’). Extrapolating from research settings to clinical settings should more rigorously take into account possible ways in which interventions can fail to be effective in a target population. Current regulatory standards for drug approval are insufficient to manage these problems of measurement.


2021 ◽  
Vol 36 (1) ◽  
pp. 561-580 ◽  
Author(s):  
Alessio Nocentini ◽  
Andrea Angeli ◽  
Fabrizio Carta ◽  
Jean-Yves Winum ◽  
Raivis Zalubovskis ◽  
...  

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