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Juan Marin

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Athanase Papadopoulos

Université de Strasbourg

Louis H Kauffman

University of Illinois at Chicago

Peter Zvengrowski

University of Illinois at Urbana-Champaign

Universidad Nacional de Colombia

Jeffrey Lagarias

SUNY: New Paltz

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Papers by Juan Marin

Marvelous cancellations": T.J. Stieltjes' letters concerning the zeta function

Cornell University - arXiv, Oct 31, 2014

This article introduces and translates letters from T.J Stieltjes (1856-1894) to C. Hermite (1822... more This article introduces and translates letters from T.J Stieltjes (1856-1894) to C. Hermite (1822-1891) regarding Stieltjes' published notes claiming to have solved Bernhard Riemann's conjecture "it is very probable that all the roots [of the zeta function] are real." These letters illuminate what was at stake in the transition between the "non-rigorous" method associated with the 18 th century and the "rigorous" approach attributed to the late 19 th. They reveal not only obsolete assumptions that no longer remain with us but also those unexamined ones that still do. Becoming aware of the issues at stake can help us understand the historical, philosophical and scientific background from which today's number theory emerged.

Abstract 2276: Microhemorrhage Burden Increases the Risk of Hematoma Growth in Patients with Intracerebral Hemorrhage

Stroke, 2012

Introduction Microhemorrhages (MH) are lesions detected on radiological studies resulting from an... more Introduction Microhemorrhages (MH) are lesions detected on radiological studies resulting from an underlying small-vessel angiopathy. We assesed the hypothesis that the presence of MH increases the risk of hematoma growth (HG) in patients with acute Intracerebral Hemorrhage (ICH). Methods We evaluated a series of patients in a prospective and multicentre study. We included patients with a spontaneous supratentorial ICH within the first 6 hours after symptom onset, that also had a follow-up CT 24-72 hours later and a MRI performed after a variable time after ICH. HG was defined as an increase >33% in the volume of hematoma on the follow-up CT, in comparison with the admission CT. The volume was calculated using the formula AxBxC/2. On MR scans we assessed the presence, number and distribution of MH. After differential diagnosis with other radiological lesions, MH were evaluated on echo-gradient sequences and defined as hypointense rounded lesions with a diameter <10mm. Statisti...

Informação Especialista para um Sistema de Filtragem Online com Ensemble de Redes Neurais em um Ambiente com Alta Taxa de Eventos

Anais do 15. Congresso Brasileiro de Inteligência Computacional, 2021

O experimento ATLAS é projetado para observar os constituintes fundamentais em colisões de partíc... more O experimento ATLAS é projetado para observar os constituintes fundamentais em colisões de partículas no Grande Colisor de Hádrons (LHC). Na próxima tomada de dados, espera-se aumentar a energia de colisão e a taxa de produção de informações, o que requer melhorias no sistema de filtragem online. O NeuralRinger é o algoritmo padrão de identificação online de elétrons no ATLAS (etapa rápida) e usa informações do calorímetro (medição de energia) organizadas em anéis concêntricos para alimentar um conjunto de redes neurais. Uma das principais características utilizadas para a discriminação de elétrons e jatos hadrônicos é o perfil lateral do chuveiro de partículas de energia decrescente, medido no calorímetro. Neste trabalho, é investigada a utilização do perfil lateral do chuveiro combinado com os anéis. O método proposto pondera os anéis gerados pelo NeuralRinger pela energia e distância até a célula mais energética. Os resultados indicaram uma redução do falso alarme de 1,37 pontos ...

A way to break bones? The weight of intuitiveness

PLOS ONE, 2021

During the Paleolithic period, bone marrow extraction was an essential source of fat nutrients fo... more During the Paleolithic period, bone marrow extraction was an essential source of fat nutrients for hunter-gatherers especially throughout cold and dry seasons. This is attested by the recurrent findings of percussion marks in osteological material from anthropized archaeological levels. Among them some showed indicators that the marrow extraction process was part of a butchery cultural practice, meaning that the inflicted fracturing gestures and techniques were recurrent, standardized and counter-intuitive. In order to assess the weight of the counter-intuitive factor in the percussion mark pattern distribution, we carried out an experiment that by contrast focuses on the intuitive approach of fracturing bones to extract marrow, involving individual without experience in this activity. We wanted to evaluate the influence of bone morphology and the individuals’ behaviour on the distribution of percussion marks. Twelve experimenters broke 120 limb bones, a series of 10 bones per indiv...

Conjunto de Redes Neurais Artificiais para Detecção Online de Fótons de Altas Energias

Anais do 15. Congresso Brasileiro de Inteligência Computacional, 2021

A correta identificação de partículas é um dos principais objetivos de experimentos de física de ... more A correta identificação de partículas é um dos principais objetivos de experimentos de física de altas energias. Devido a alta taxa de eventos no Grande Colisor de Hádrons (LHC), o experimento ATLAS tem empregado técnicas baseadas em aprendizado de máquina a fim de encontrar eventos raros em grandes massas de dados. Entre eles está o NeuralRinger, um conjunto classificador de rede neural projetado para detecção rápida de elétrons com base em anéis concêntricos de calorímetro (sistema de medição de energia). Nesse contexto, o presente trabalho propõe a adaptação desta técnica, que opera identificando elétrons, para a detecção rápida de fótons. Os resultados com dados simulados mostram a eficiência do método proposto no ambiente do experimento ATLAS.

Uma Proposta para Calibração do Sistema Online de Seleção de Eventos no Detector ATLAS utilizando Gradient Boosted Decision Trees

Anais do 15. Congresso Brasileiro de Inteligência Computacional, 2021

Particle physics experiments deal with a huge volume of information and a complex sequential proc... more Particle physics experiments deal with a huge volume of information and a complex sequential processing chain for online selection (trigger) of events. In the ATLAS experiment at the Large Hadron Collider (LHC), the trigger system is responsible for choosing the events that will be recorded on permanent media for future analysis and operates sequentially in two levels of selection. The estimated value of energy deposited by particles in the detector is an important parameter for the online selection process. In this work, a calibration method based on gradient boosted decision trees ensemble is proposed to improve the quality of the energy estimated in the second trigger stage of the ATLAS detector. With the proposed method it is possible, at the same time, to reduce computational requirements and increase the selection efficiency of electromagnetic particles (electrons).

El Guernica de picasso: Cincuenta años de historia

Boletin Del Museo E Instituto Camon Aznar, 1987

Le "Guernica" de Picasso comme instance de légitimation

Media Et Representation Dans Le Monde Hispanique Au Xxe Siecle 1987 Pags 183 190, 1987

Conservación, difusión y valorización del patrimonio prehistórico en el Calerizo de Cáceres y su entorno

Vi Encuentro De Arqueologia Del Suroeste Peninsular 2013 Isbn 978 84 616 6306 4 Pags 2249 2264, 2013

Cela/Picasso: dibujos y retratos. En torno a un encuentro y a una colaboración

Hispanistica Xx, 1990

Sobre los criterios de agotamiento de uniones en ángulo sometidas a solicitaciones estáticas

Soldadura Y Tecnologias De Union, 2000

Botero ou l'incarnation. Une approche anthropologique du style

Hispanistica Xx, 1994

Buda o la negación del mundo

Trace conditions for symmetry of the numerical range

The Electronic Journal of Linear Algebra, 2013

$where * denotes an unspecified entry. Note then that Proof. Assume that A isa 4x4 ma trix whose eigenvalues have 4-sato. Then there exists a € C such that these eigenvalues are \, = a, Ay = ae? = ai, \3 = ae™ = —a, 3mi and \4 = ae? = —ai. Results in [3] show that if A is nilpotent with the given trace conditions, then W(A) is a disk whic h clearly has 4-sato. Hence, we may assume a #0. Every matrix is unitarily equivalent to an upper triangular matrix, and thus, the unitary invariance of the numerica range allows us to assume that Recall that the support function of W(A) is defined by$

Tactics, Techniques, and Procedures to Extend Component Remaining Useful Life Based on Aircraft Maneuvers

Sustainment Operations rely on reliability centered maintenance approaches to determine component... more Sustainment Operations rely on reliability centered maintenance approaches to determine component retirement regardless of actual remaining useful life. With maintenance actions accounting for a significant portion of overall operating costs, operators seek approaches that maximize service intervals. Integrated Vehicle Health Management concepts afford an adaptive approach that can reduce the frequency of required maintenance actions based on proactively managing the damage incurred during flight operations. Tactics to gain airworthiness approval for extending remaining useful life and instructions for maintaining continued airworthiness are proposed. Techniques to identify, quantify, substantiate, and validate component failure rates for basic flight maneuvers are discussed. Finally, a pilot cueing system and the procedures for recommending pilot actions to manage health during flight operations are presented.

Endoscopic and histological evaluations of a newly designed inguinal hernia mesh implant: Experimental studies on porcine animal model and human cadaver

Annals of Medicine and Surgery, 2015

h i g h l i g h t s Feasibility-study to test a new-3D tension-free prosthesis in an experimental... more

Severity stages in essential tremor: a long-term retrospective study using the glass scale

Tremor and other hyperkinetic movements (New York, N.Y.), 2015

Few prospective studies have attempted to estimate the rate of decline of essential tremor (ET) a... more Few prospective studies have attempted to estimate the rate of decline of essential tremor (ET) and these were over a relatively short time period (less than 10 years). We performed a long-term study of severity stages in ET using the Glass Scale scoring system. Fifty consecutive patients with severe ET were included. We retrospectively obtained Glass Scale scores throughout the patient's life. Common milestone events were used to help recall changes in tremor severity. According to the Glass Scale, the age distributions were as follows: score I, 40±17 years, score II, 55±12 years, score III, 64±9 years, and score IV, 69±7 years. A significant negative correlation between age at first symptom and rate of progression was found (r = -0.669, p<0.001). The rate of progression was significantly different (p<0.001) when the first symptom appeared at a younger age (under 40 years of age) compared with older age (40 years or older). Our results support the progressive nature of ET...

Energy sources for laparoscopic colectomy: a prospective randomized comparison of conventional electrosurgery, bipolar computer-controlled electrosurgery and ultrasonic dissection. Operative outcome and costs analysis

Surgical innovation, 2005

The development of operative laparoscopic surgery is linked to advances in ancillary surgical ins... more The development of operative laparoscopic surgery is linked to advances in ancillary surgical instrumentation. Ultrasonic energy devices avoid the use of electricity and provide effective control of small- to medium-sized vessels. Bipolar computer-controlled electrosurgical technology eliminates the disadvantages of electrical energy, and a mechanical blade adds a cutting action. This instrument can provide effective hemostasis of large vessels up to 7 mm. Such devices significantly increase the cost of laparoscopic procedures, however, and the amount of evidence-based information on this topic is surprisingly scarce. This study compared the effectiveness of three different energy sources on the laparoscopic performance of a left colectomy. The trial included 38 nonselected patients with a disease of the colon requiring an elective segmental left-sided colon resection. Patients were preoperatively randomized into three groups. Group I had electrosurgery; vascular dissection was perf...

Anaerobic Digestion of Fermentation Residuals for Energy Self-Sufficient Bioethanol Plant Operation

Proceedings of the Water Environment Federation, 2009

Anaerobic digestion of whole stillage from a corn-based ethanol plant was evaluated by batch and ... more Anaerobic digestion of whole stillage from a corn-based ethanol plant was evaluated by batch and continuous-flow digesters under thermophilic and mesophilic conditions. At whole corn stillage concentrations of 6348 to 50786 mg total chemical oxygen demand (TCOD)/L, preliminary biochemical methane potential assays produced similar amount of biogas, which was 84 L (57 L CH 4) and 87 L (52 L CH 4) per kg stillage from thermophilic and mesophilic digesters, respectively. Continuous-flow studies for the full-strength stillage (TCOD = 254 g/L) at organic loadings of 4.25, 6.3 and 9.05 g TCOD/L. d indicated unstable performance for the thermophilic digester. Among the sludge retention times (SRTs) of 60, 45 and 30 d tested, the mesophilic digestion was successful only at 60 d-SRT which does not represent a practical operation time for a large scale bioethanol plant. Future laboratory studies will focus on different reactor configurations to reduce the SRT needed in the digesters.

Interfacial Instabilities in a Two Layer Coextrusion during Cable Coating

The paper describes a study leading to a modification of a coextrusion die. This modification sta... more

Marvelous cancellations": T.J. Stieltjes' letters concerning the zeta function

Cornell University - arXiv, Oct 31, 2014

This article introduces and translates letters from T.J Stieltjes (1856-1894) to C. Hermite (1822... more This article introduces and translates letters from T.J Stieltjes (1856-1894) to C. Hermite (1822-1891) regarding Stieltjes' published notes claiming to have solved Bernhard Riemann's conjecture "it is very probable that all the roots [of the zeta function] are real." These letters illuminate what was at stake in the transition between the "non-rigorous" method associated with the 18 th century and the "rigorous" approach attributed to the late 19 th. They reveal not only obsolete assumptions that no longer remain with us but also those unexamined ones that still do. Becoming aware of the issues at stake can help us understand the historical, philosophical and scientific background from which today's number theory emerged.

Abstract 2276: Microhemorrhage Burden Increases the Risk of Hematoma Growth in Patients with Intracerebral Hemorrhage

Stroke, 2012

Introduction Microhemorrhages (MH) are lesions detected on radiological studies resulting from an... more Introduction Microhemorrhages (MH) are lesions detected on radiological studies resulting from an underlying small-vessel angiopathy. We assesed the hypothesis that the presence of MH increases the risk of hematoma growth (HG) in patients with acute Intracerebral Hemorrhage (ICH). Methods We evaluated a series of patients in a prospective and multicentre study. We included patients with a spontaneous supratentorial ICH within the first 6 hours after symptom onset, that also had a follow-up CT 24-72 hours later and a MRI performed after a variable time after ICH. HG was defined as an increase >33% in the volume of hematoma on the follow-up CT, in comparison with the admission CT. The volume was calculated using the formula AxBxC/2. On MR scans we assessed the presence, number and distribution of MH. After differential diagnosis with other radiological lesions, MH were evaluated on echo-gradient sequences and defined as hypointense rounded lesions with a diameter <10mm. Statisti...

Informação Especialista para um Sistema de Filtragem Online com Ensemble de Redes Neurais em um Ambiente com Alta Taxa de Eventos

Anais do 15. Congresso Brasileiro de Inteligência Computacional, 2021

O experimento ATLAS é projetado para observar os constituintes fundamentais em colisões de partíc... more O experimento ATLAS é projetado para observar os constituintes fundamentais em colisões de partículas no Grande Colisor de Hádrons (LHC). Na próxima tomada de dados, espera-se aumentar a energia de colisão e a taxa de produção de informações, o que requer melhorias no sistema de filtragem online. O NeuralRinger é o algoritmo padrão de identificação online de elétrons no ATLAS (etapa rápida) e usa informações do calorímetro (medição de energia) organizadas em anéis concêntricos para alimentar um conjunto de redes neurais. Uma das principais características utilizadas para a discriminação de elétrons e jatos hadrônicos é o perfil lateral do chuveiro de partículas de energia decrescente, medido no calorímetro. Neste trabalho, é investigada a utilização do perfil lateral do chuveiro combinado com os anéis. O método proposto pondera os anéis gerados pelo NeuralRinger pela energia e distância até a célula mais energética. Os resultados indicaram uma redução do falso alarme de 1,37 pontos ...

A way to break bones? The weight of intuitiveness

PLOS ONE, 2021

During the Paleolithic period, bone marrow extraction was an essential source of fat nutrients fo... more During the Paleolithic period, bone marrow extraction was an essential source of fat nutrients for hunter-gatherers especially throughout cold and dry seasons. This is attested by the recurrent findings of percussion marks in osteological material from anthropized archaeological levels. Among them some showed indicators that the marrow extraction process was part of a butchery cultural practice, meaning that the inflicted fracturing gestures and techniques were recurrent, standardized and counter-intuitive. In order to assess the weight of the counter-intuitive factor in the percussion mark pattern distribution, we carried out an experiment that by contrast focuses on the intuitive approach of fracturing bones to extract marrow, involving individual without experience in this activity. We wanted to evaluate the influence of bone morphology and the individuals’ behaviour on the distribution of percussion marks. Twelve experimenters broke 120 limb bones, a series of 10 bones per indiv...

Conjunto de Redes Neurais Artificiais para Detecção Online de Fótons de Altas Energias

Anais do 15. Congresso Brasileiro de Inteligência Computacional, 2021

A correta identificação de partículas é um dos principais objetivos de experimentos de física de ... more A correta identificação de partículas é um dos principais objetivos de experimentos de física de altas energias. Devido a alta taxa de eventos no Grande Colisor de Hádrons (LHC), o experimento ATLAS tem empregado técnicas baseadas em aprendizado de máquina a fim de encontrar eventos raros em grandes massas de dados. Entre eles está o NeuralRinger, um conjunto classificador de rede neural projetado para detecção rápida de elétrons com base em anéis concêntricos de calorímetro (sistema de medição de energia). Nesse contexto, o presente trabalho propõe a adaptação desta técnica, que opera identificando elétrons, para a detecção rápida de fótons. Os resultados com dados simulados mostram a eficiência do método proposto no ambiente do experimento ATLAS.

Uma Proposta para Calibração do Sistema Online de Seleção de Eventos no Detector ATLAS utilizando Gradient Boosted Decision Trees

Anais do 15. Congresso Brasileiro de Inteligência Computacional, 2021

Particle physics experiments deal with a huge volume of information and a complex sequential proc... more Particle physics experiments deal with a huge volume of information and a complex sequential processing chain for online selection (trigger) of events. In the ATLAS experiment at the Large Hadron Collider (LHC), the trigger system is responsible for choosing the events that will be recorded on permanent media for future analysis and operates sequentially in two levels of selection. The estimated value of energy deposited by particles in the detector is an important parameter for the online selection process. In this work, a calibration method based on gradient boosted decision trees ensemble is proposed to improve the quality of the energy estimated in the second trigger stage of the ATLAS detector. With the proposed method it is possible, at the same time, to reduce computational requirements and increase the selection efficiency of electromagnetic particles (electrons).

El Guernica de picasso: Cincuenta años de historia

Boletin Del Museo E Instituto Camon Aznar, 1987

Le "Guernica" de Picasso comme instance de légitimation

Media Et Representation Dans Le Monde Hispanique Au Xxe Siecle 1987 Pags 183 190, 1987

Conservación, difusión y valorización del patrimonio prehistórico en el Calerizo de Cáceres y su entorno

Vi Encuentro De Arqueologia Del Suroeste Peninsular 2013 Isbn 978 84 616 6306 4 Pags 2249 2264, 2013

Cela/Picasso: dibujos y retratos. En torno a un encuentro y a una colaboración

Hispanistica Xx, 1990

Sobre los criterios de agotamiento de uniones en ángulo sometidas a solicitaciones estáticas

Soldadura Y Tecnologias De Union, 2000

Botero ou l'incarnation. Une approche anthropologique du style

Hispanistica Xx, 1994

Buda o la negación del mundo

Trace conditions for symmetry of the numerical range

The Electronic Journal of Linear Algebra, 2013

$where * denotes an unspecified entry. Note then that Proof. Assume that A isa 4x4 ma trix whose eigenvalues have 4-sato. Then there exists a € C such that these eigenvalues are \, = a, Ay = ae? = ai, \3 = ae™ = —a, 3mi and \4 = ae? = —ai. Results in [3] show that if A is nilpotent with the given trace conditions, then W(A) is a disk whic h clearly has 4-sato. Hence, we may assume a #0. Every matrix is unitarily equivalent to an upper triangular matrix, and thus, the unitary invariance of the numerica range allows us to assume that Recall that the support function of W(A) is defined by$

Tactics, Techniques, and Procedures to Extend Component Remaining Useful Life Based on Aircraft Maneuvers

Sustainment Operations rely on reliability centered maintenance approaches to determine component... more Sustainment Operations rely on reliability centered maintenance approaches to determine component retirement regardless of actual remaining useful life. With maintenance actions accounting for a significant portion of overall operating costs, operators seek approaches that maximize service intervals. Integrated Vehicle Health Management concepts afford an adaptive approach that can reduce the frequency of required maintenance actions based on proactively managing the damage incurred during flight operations. Tactics to gain airworthiness approval for extending remaining useful life and instructions for maintaining continued airworthiness are proposed. Techniques to identify, quantify, substantiate, and validate component failure rates for basic flight maneuvers are discussed. Finally, a pilot cueing system and the procedures for recommending pilot actions to manage health during flight operations are presented.

Endoscopic and histological evaluations of a newly designed inguinal hernia mesh implant: Experimental studies on porcine animal model and human cadaver

Annals of Medicine and Surgery, 2015

h i g h l i g h t s Feasibility-study to test a new-3D tension-free prosthesis in an experimental... more

Severity stages in essential tremor: a long-term retrospective study using the glass scale

Tremor and other hyperkinetic movements (New York, N.Y.), 2015

Few prospective studies have attempted to estimate the rate of decline of essential tremor (ET) a... more Few prospective studies have attempted to estimate the rate of decline of essential tremor (ET) and these were over a relatively short time period (less than 10 years). We performed a long-term study of severity stages in ET using the Glass Scale scoring system. Fifty consecutive patients with severe ET were included. We retrospectively obtained Glass Scale scores throughout the patient's life. Common milestone events were used to help recall changes in tremor severity. According to the Glass Scale, the age distributions were as follows: score I, 40±17 years, score II, 55±12 years, score III, 64±9 years, and score IV, 69±7 years. A significant negative correlation between age at first symptom and rate of progression was found (r = -0.669, p<0.001). The rate of progression was significantly different (p<0.001) when the first symptom appeared at a younger age (under 40 years of age) compared with older age (40 years or older). Our results support the progressive nature of ET...

Energy sources for laparoscopic colectomy: a prospective randomized comparison of conventional electrosurgery, bipolar computer-controlled electrosurgery and ultrasonic dissection. Operative outcome and costs analysis

Surgical innovation, 2005

The development of operative laparoscopic surgery is linked to advances in ancillary surgical ins... more The development of operative laparoscopic surgery is linked to advances in ancillary surgical instrumentation. Ultrasonic energy devices avoid the use of electricity and provide effective control of small- to medium-sized vessels. Bipolar computer-controlled electrosurgical technology eliminates the disadvantages of electrical energy, and a mechanical blade adds a cutting action. This instrument can provide effective hemostasis of large vessels up to 7 mm. Such devices significantly increase the cost of laparoscopic procedures, however, and the amount of evidence-based information on this topic is surprisingly scarce. This study compared the effectiveness of three different energy sources on the laparoscopic performance of a left colectomy. The trial included 38 nonselected patients with a disease of the colon requiring an elective segmental left-sided colon resection. Patients were preoperatively randomized into three groups. Group I had electrosurgery; vascular dissection was perf...

Anaerobic Digestion of Fermentation Residuals for Energy Self-Sufficient Bioethanol Plant Operation

Proceedings of the Water Environment Federation, 2009

Anaerobic digestion of whole stillage from a corn-based ethanol plant was evaluated by batch and ... more Anaerobic digestion of whole stillage from a corn-based ethanol plant was evaluated by batch and continuous-flow digesters under thermophilic and mesophilic conditions. At whole corn stillage concentrations of 6348 to 50786 mg total chemical oxygen demand (TCOD)/L, preliminary biochemical methane potential assays produced similar amount of biogas, which was 84 L (57 L CH 4) and 87 L (52 L CH 4) per kg stillage from thermophilic and mesophilic digesters, respectively. Continuous-flow studies for the full-strength stillage (TCOD = 254 g/L) at organic loadings of 4.25, 6.3 and 9.05 g TCOD/L. d indicated unstable performance for the thermophilic digester. Among the sludge retention times (SRTs) of 60, 45 and 30 d tested, the mesophilic digestion was successful only at 60 d-SRT which does not represent a practical operation time for a large scale bioethanol plant. Future laboratory studies will focus on different reactor configurations to reduce the SRT needed in the digesters.

Interfacial Instabilities in a Two Layer Coextrusion during Cable Coating

The paper describes a study leading to a modification of a coextrusion die. This modification sta... more