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Las técnicas de aplicación de las pinturas rupestres resultan fundamentales para comprender sus procesos de producción, pues permiten acceder a las interacciones constitutivas entre seres, materiales, tiempos y espacios que se entablan al hacer los motivos. Sin embargo, son escasas las investigaciones centradas en identificar marcadores materiales específicos que permitan diferenciar entre la multiplicidad de técnicas de aplicación posibles. En líneas generales, estas se han inferido a partir de criterios poco explicitados. Este trabajo plantea un abordaje experimental de cuatro técnicas de aplicación (digital, con hisopo, con pincel y con palito) con vistas a detectar huellas específicas a cada una. Posteriormente, se aplican estos conocimientos para avanzar en el relevamiento macroscópico de las pinturas rupestres de la cueva de La Candelaria (departamento Ancasti, Catamarca). Ello posibilitó identificar huellas de diversas técnicas de aplicación en las pinturas del sitio, demostrando la importancia de retroalimentar los relevamientos in situ con estudios experimentales.

Abstract Could not be possible that rock paintings with similar hues and morphologies were the result of different paint preparations inside a cave but distanced in time? Is there any archaeometric approach that allow us to evidence these subtle differences? Aiming to address these inquires, in this work are presented the potentials of new physicochemical lines of evidence for characterization and differentiation of paint mixtures. This will improve the understanding of the technical heterogeneity and temporal complexity of painting sets executed in a particular archaeological site. In order to explore these points, the results obtained in the micro-stratigraphic studies of samples taken from the painted walls of Oyola, an archaeological site located in the northwest of Argentina, are presented. These samples have been analyzed by micro-Raman spectroscopy (mRS) and scanning electron microscopy with energy dispersive X-ray (SEM–EDS). The differences found by cross-section chemical studies could be explained as a consequence of two situations: 1-differences in the painting’s chemical components, either in the pigments involved or additives used; and, 2-differences in the physical properties of the mixtures such as stratum thickness and/or particle size. Also, in this article are explained each of the hypothesis, presenting the limits of these interpretations and pointing out future research challenges. As we discussed, it could be possible that the chemical and physical differences found between paint mixtures were the material expression of varied types of pictorial techniques.

Desde una perspectiva histórica y a partir de la materialidad de dos piezas pictóricas, esta investigación pretende reflexionar sobre materiales, técnicas, usos y costumbres en la pintura colonial. Sobre un corpus de más de cuatrocientas obras del período colonial intervenidas, la propuesta implica analizar los soportes principales y accesorios de dos obras sudamericanas, San Luis Gonzaga y San Juan Nepomuceno, pertenecientes a la Iglesia de San Ignacio en la ciudad de Buenos Aires, Argentina.

Alrededor de 1930 el pintor argentino Antonio Berni desarrolla el “Nuevo Realismo”. Dentro de esta corriente ejecuta grandes composiciones, con grupos de campesinos y obreros como la obra que aquí presentamos: “Chacareros” (1935). El soporte está constituido por la unión de varias telas de arpillera precedentes de sacos de azúcar cosidas entre sí. Su elección no fue una anécdota, sino la búsqueda consciente de un recurso expresivo. El importante deterioro de las fibras, ponía en riesgo la supervivencia de esta pintura, por lo que una intervención se hacía necesaria. El presente trabajo muestra el tratamiento de restauración de “Chacareros”. Este se realizó atendiendo al difícil problema de un soporte atípico y las exigencias de historicidad que el mismo imponía. Este proyecto ha dado también la oportunidad de examinar esta obra emblemática de la pintura argentina del siglo XX, e iniciar así, por primera vez, las investigaciones científico-técnicas para caracterizar los materiales y las técnicas pictóricas de Berni.

Cyber–physical systems use digital twins to provide advanced monitoring and control functions, including self-diagnosis. The digital twin is often conceptualized as a 3D model, but mathematical models implemented in numerical simulations are required to reproduce the dynamical and functional characteristics of physical systems. In this work, a cyber–physical system scheme is proposed to monitor and diagnose failures. The virtual system, embedded at the supervisory control level, combines concepts from complex networks and hybrid automata to detect failures in the hardware components and in the execution of the sequential logic control. An automated storage and retrieval system is presented as a case study to show the applicability of the proposed scheme. The functional test and the obtained results validate the implemented system that is shown to be capable of fault diagnosis and location in real time. The online execution of the digital twin present several advantages for diagnosing multiple concurrent failures in sensors, actuators, and the control unit. This approach can be incorporate into diverse manufacturing systems.

The peak demand or demand limit control is an important part of the actions that industries carry out to optimize their energy consumption and reduce the costs related to their electricity billing. Prioritized switching of multiple appliances is often needed in order to reduce demand and energy consumption during peak load periods. The present article describes a peak load limitation algorithm that estimates the optimal disconnection time for one or more electrical loads before the electric demand exceeds a preset limit. This algorithm uses parametric and variable load factors that vary dynamically depending on what loads are present at a given time. For its validation, a software-in-the-loop testbed was designed and developed, in which multiple electrical loads were simulated via LabVIEW software and connected to a PLC controller emulated through CODESYS software. In this environment, several test configurations were executed and evaluated to study the influence of variables such as the nominal power and the disconnection priority of loads in the algorithm output. The results showed that the control algorithm is effective for peak load limitation, the maximum demand value reached during simulations tests did not exceed the preset demand limit at any time interval. The performance of the algorithm could be improved when prioritizing the shutdown of loads with higher nominal power or when increasing the anticipation time used for the disconnection of the controllable loads.

Virtual remote laboratories have already been successfully implemented in educational centers for practical learning of mechatronics and robotic systems. This article presents the development of a virtual articulated UR-type robot, designed as an educational tool that is suitable for programming and evaluating both the inverse kinematics control of the robot and the independent control of the robot joints. The 3D model of the virtual robot was developed in the Blender V2.79 software and uses the Modbus TCP industrial communication protocol for the communication to an external controller implemented in CoDeSys V3.5 software. The developed system allows the students to generate and test their own control algorithm for the robot joints with the visualization of the achieved performance in 3D and real time. Tailored control systems can be compared on the virtual robot. In this study, a novel technique for the joint position control based on an FSM is proposed and verified with the virtual UR5 robots to prove that the developed system is a suitable platform to teach and learn the inverse kinematics control and independent joint control of the UR5 robotic arm.

Improving the strategies employed to control robotic arms is of great importance because of the increase in their use in advanced supervisory control strategies, such as digital twins. The inverse kinematic (IK) control of manipulators requires an IK solution and an awareness of the singular configurations. This work presents a complete IK calculation system with singularity analysis for the UR5 robotic arm created by Universal Robots. For a specific robot pose, different angle solution sets are obtained, and one of these solution sets has to be selected to achieve movement continuity and avoid singularities. Two methods for this double purpose are proposed: one calculates all the solution possibilities, and the other obtains only one solution set by following a sequence of decisions and calculations clearly stated by a finite state machine (FSM). Both methods are effective in managing singularities. The FSM-based method complements the IK solution procedure with advantages in the number of computations and performance by producing results that would not lead the joints to move abruptly. The results prove that the presented methods select an IK solution that does not result in a singular configuration, and that most of the time, they lead to the same valid IK solution.

Sustainable, stable, and cost-optimized operation of power grids must be the main objectives of power grid operators and electric utilities. The energy transition towards a preponderant green energy economy requires innovative solutions to enhance the power grid economic dispatches looking for a better allocation of the energy demand among the diverse renewable and fossil fuel energy plants. Green renewable energy systems must be preferred over fossil fuel generators when they are available. However, fossil plants are still required to be kept operational due to the variability and uncertainty of renewable energy plants. This study proposes a hybrid rational economic dispatch model that combines a cost minimization linear model enhanced with a fuzzy logic system for decision-making on wind and hydropower minimum and maximum generation levels. The model considers the intermittency of wind energy and recognizes the strategic value of hydropower as energy storage. The results of the model with real data taken from wind, hydroelectric, geothermal, nuclear, bioenergy, and fossil fuel power plants in the eastern region of Mexico show that a fairer, rational, and cost-optimized power grid economic dispatch can be achieved with the proposed approach.

In this work, the seasonal and yearly optical performance of supported catalyst CPC solar photocatalytic reactors has been theoretically analyzed. A detailed model for the optical response of the anatase catalyst films is utilized, based on the characteristic matrix method, together with Monte Carlo ray tracing simulations. The catalyst is supported over glass tubes contained inside a larger glass tube that functions as receiver of the CPC reflector. Arrangements with four, five, and six tubes are considered. Overall, the four-tube scenario presents the worst performance of all, followed by the five-tube case. In general, the six-tube configuration is better. Nevertheless, important differences can be observed depending on the specific arrangement of tubes. The six-tube case surpasses the absorption rate of all the other configurations when the distance between tubes is extended. This configuration exhibits 27% increased yearly energy absorption with respect to the reference case and 47% with respect to the worst case scenario.

Apresenta-se um caso clínico referente a doente de 35 anos, do sexo masculino sem antecedentes pessoais relevantes, admitido no serviço de urgência por quadro de toracalgia e tosse produtiva com alterações electrocardiograficas sugestivas de pericardite. Inicialmente admitido pelo Serviço de Cardiologia, com melhoria do quadro clínico apos terapêutica anti-inflamatória; contudo, no internamento houve como intercorrencia pneumonia de provável etiologia bacteriana, complicada por derrame pleural. Após a alta, foi referenciado a consulta de pneumologia, onde se manteve o estudo etiológico do derrame persistente, tendo vindo a complicar-se o seu quadro com alterações das cavidades cardíacas e múltiplos nódulos pulmonares, sugestivos de endocardite subaguda com embolização séptica pulmonar. Internado no serviço de Pneumologia e submetido a videotoracoscopia, foi-lhe diagnosticado angiossarcoma cardíaco com metastização pulmonar. Assistiu-se a uma rápida evolução do quadro clínico, quase fulminante, com falência cardíaca e óbito do doente sem ter iniciado radioterapia ou quimioterapia adjuvante.We present a case report of a 35 year-old male without any relevant former pathology admitted to the emergency room with atypical chest pain, cough and sputum with ECG changes suggesting pericarditis. He was initially admitted to the cardiology ward and experienced clinical improvement after initiating anti- inflammatory treatment. As intercurrence he had bacterial origin pneumonia complicated by pleural effusion (PE). After discharge patient was referred to a pulmonology appointment where aetiological investigation of the PE was instigated. Investigation revealed changes in the cardiac cavities and multiple lung nodules, suggesting subacute endocarditis with septic pulmonary embolism. Admitted to the pulmonology unit patient underwent videothoracsopy which diagnosed cardiac angiosarcoma with pulmonary metastisation. Within a few days there was a rapid evolution of the clinical picture, with cardiac failure and death of the patient without radiotherapy or adjuvant chemotherapy being started.

Resumo: Apresenta-se um caso clínico referente a doente de 35 anos, do sexo masculino sem antecedentes pessoais relevantes, admitido no serviço de urgência por quadro de toracalgia e tosse produtiva com alterações electrocardiográficas sugestivas de pericardite. Inicialmente admitido pelo Serviço de Cardiologia, com melhoria do quadro clínico após terapêutica anti-inflamatória; contudo, no internamento houve como intercorrência pneumonia de provável etiologia bacteriana, complicada por derrame pleural. Após a alta, foi referenciado à consulta de pneumologia, onde se manteve o estudo etiológico do derrame persistente, tendo vindo a complicar-se o seu quadro com alterações das cavidades cardiacas e múltiplos nódulos pulmonares, sugestivos de endocardite subaguda com embolização séptica pulmonar. Internado no serviço de Pneumologia e submetido a videotoracoscopia, foi-lhe diagnosticado angiossarcoma cardíaco com metastização pulmonar. Assistiu-se a uma rápida evolução do quadro clínico, quase fulminante, com falência cardíaca e óbito do doente sem ter iniciado radioterapia ou quimioterapia adjuvante.Rev Port Pneumol 2009; XV (6): 1175-1184 Abstract: We present a case report of a 35 year-old male without any relevant former pathology admitted to the emergency room with atypical chest pain, cough and sputum with ECG changes suggesting pericarditis. He was initially admitted to the cardiology ward and experienced clinical improvement after initiating anti-inflammatory treatment. As intercurrence he had bacterial origin pneumonia complicated by pleural effusion (PE). After discharge patient was referred to a pulmonology appointment where aetiological investigation of the PE was instigated. Investigation revealed changes in the cardiac cavities and multiple lung nodules, suggesting subacute endocarditis with septic pulmonary embolism. Admitted to the pulmonology unit patient underwent videothoracsopy which diagnosed cardiac angiosarcoma with pulmonary metastisation. Within a few days there was a rapid evolution of the clinical picture, with cardiac failure and death of the patient without radiotherapy or adjuvant chemotherapy being started.Rev Port Pneumol 2009; XV (6): 1175-1184 Palavras-chave: Angiossarcoma cardíaco, metástases pulmonares, derrame pleural, pericardite, Key-words: Heart angiosarcoma, pulmonary metastasis, pleural effusion, pericarditis

RESUMO: Pretende-se neste trabalho fazer uma revisão retrospectiva duma patologia, rara na sua incidência (5% de todos os tumores pleurais) e singular nas suas características, analisando na nossa casuística as formas de apresentação, terapêutica cirúrgica e resultados obtidos.Os tumores solitários da pleura são formações neoplásicas raras, cujo comportamento biológico não é obrigatoriamente correlacionável com características imuno-histoquímicas, pois os considerados benignos apresentam um sensível índice de recidiva e metastização, independentemente do volume que apresentam.A cirurgia é o único tratamento disponível e a excisão cirúrgica completa é decisiva para a cura.De Agosto de 1995 a Janeiro de 2003, na casuística do Serviço de Cirurgia Cardiotorácica do Hospital de Santa Marta, foram analisados todos os doentes com o diagnóstico de tumor fibroso localizado da pleura (TFLP).Neste contexto, identificaram-se 11 doentes com idade média de 57,54 anos, dos quais 6 do sexo feminino, em que foi colocado o diagnóstico de tumor fibroso localizado da pleura; 6 dos tumores foram classificados como malignos e 5 como benignos.Nesta série, todos os doentes foram submetidos a intervenção cirúrgica, com técnicas variadas, sem mortalidade intra-operatória ou morbilidade intra-hospitalar significativas, apesar da dificuldade da cirurgia nos tumores mais volumosos (um dos tumores pesava 2,5 kg).O follow up decorreu entre os 4 e os 84 meses (média â 39,4 meses).Um doente faleceu 13 meses após a intervenção, por embolia pulmonar maciça, depois de várias crises de tromboembolismo pulmonar (sem relação determinável com a cirurgia ou a patologia base), apesar da anticoagulação iniciada e controlada na Consulta do Hospital.REV PORT PNEUMOL 2003; IX (6): 493-501 ABSTRACT: We present a retrospective revision of a pathology, rare in his incidence (5% of the pleural tumours) and singular in his characteristics, analyzing the presentation forms, surgical treatment and results.The solitary tumours of the pleura are a rare entity, whose biological behaviour is not related with immunohistochemical characteristics; although considered benign, they present sensitive recidivation index and metastization, independently of the volume that they present.The surgery is the only available treatment, and complete surgical excision is decisive.From August 1995 to January 2003, in the casuistry of the Department of Cardiothoracic Surgery in Santa Martaâs Hospital, were analyzed all the patients with the diagnosis of localized fibrous tumour of the pleura (TFLP). In this context, were identified 11 patients with a medium age of 57,54 years old, 6 of them females, in which the diagnosis of located fibrous tumour of the pleura was established; 6 of the tumours were classified as malignant.All the patients were submitted to surgical excision, with different techniques, without significant intra-operative mortality or intra-hospital morbidity, despite the difficulty of surgery in the most voluminous tumours (one of the tumours weight was 2,5 kg).The follow up elapsed between 4 and 84 months (average â 39,4 months).One patient died 13 months after the surgery, after several crises of lung embolism (that began without determinable relationship with the surgery or the initial pathology), despite the controlled ambulatory anti-coagulation.REV PORT PNEUMOL 2003; IX (6): 493-501 Palavras-chave: pleura, tumor fibroso, tumor fibroso localizado, Key-words: pleura, fibrous tumor, localized fibrous tumor

Electric arc furnaces (EAFs) contribute to almost one third of the global steel production. Arc furnaces use a large amount of electrical energy to process scrap or reduced iron and are relevant to study because small improvements in their efficiency account for significant energy savings. Optimal controllers need to be designed and proposed to enhance both process performance and energy consumption. Due to the random and chaotic nature of the electric arcs, neural networks and other soft computing techniques have been used for modeling EAFs. This study proposes a methodology for modeling EAFs that considers the time varying arc length as a relevant input parameter to the arc furnace model. Based on actual voltages and current measurements taken from an arc furnace, it was possible to estimate an arc length suitable for modeling the arc furnace using neural networks. The obtained results show that the model reproduces not only the stable arc conditions but also the unstable arc conditions, which are difficult to identify in a real heat process. The presented model can be applied for the development and testing of control systems to improve furnace energy efficiency and productivity.

Here I propose procedural replication as a method for diagnosing errors and omissions and identifying research artifacts in published studies. The goal of procedural replication is not to make substantive contributions so much as improve research practice, or how scientists go about doing science. This is accomplished by generating checklists of lessons learned that scholars can use to assess the reliability of new or existing studies, guide editorial reviews, and make scientific knowledge production more reliable. I demonstrate the method by implementing a procedural replication of Michael Ross’s controversial finding that democracy has no effect on child mortality. I find this null finding is an artifact of the way five-year averages were computed and the static nature of the preferred model. I demonstrate, using causal diagrams, how concerns about listwise deletion and selection bias affecting previous studies may have been overstated. I also provide a checklist with lessons learned.

Resumo: Relatase o caso de uma doente de 75 anos que em Out./2004 recorreu ao SU por queixas de tosse, febre e toracalgia esq. Com características pleuríticas. A semiologia pulmonar foi compatível com derrame pleural esq. E procedeu-se à respectiva investigação clínica. Existiam parâmetros de infecção elevados no contexto de um exsudado pleural. A tomografia computorizada evidenciou derrame pleural e espessamento no segmento anterior do LSD, cuja bronco-fibroscopia apenas visualizou alterações inflamatórias. Em Fev./2005 verifica-se recidiva do derrame pleural. A tomografia computorizada referia agora a existência de densificação nodular adjacente ao BLSE e língula. Em conjunto com a equipa de cirurgia torácica, foi decidido procederse a videoto-racoscopia. Durante a realização da técnica houve necessidade de conversão para toracotomia e o pós-operatório foi moroso. O exame histológico revelou um CPNPC â adenocarcinoma. A doente iniciou quimioterapia de primeira linha e em Mar./2006 sur-giu metastização óssea. Efectua quimioterapia de segunda linha, tendo-se mantido em doença estável, e em Jul./2007 inicia terapêutica com erlotinib que mantém actualmente, com boa tolerância, sem queixas álgicas e sem progressão da doença sob 13 meses de terapêutica. E até quando esta resposta?Rev Port Pneumol 2008; XIV (Supl 3): S71-S77 Abstract: A 75 year old woman was observed at the emergency department with cough, hyperthermia and thoracic pain in October 2004.A pleural effusion was identified and studied. Thorax CT scan evidenced a pleural effusion and thickening in the RSL anterior segment but bronchofibroscopy only identified inflammatory changes. In February 2005 the pleural effusion relapsed and the CT scan showed nodular densification adjacent to LSLB and lingual. VATS converted to thoracotomy was preformed and followed by a long recover period. Histology of surgical specimen revealed an adenocarcinoma. First line CT was administered until progression as bone metastasis, in March 2006. Second line CT was started, with disease stabilization. The administration of erlotinib was started in July 2007 and continues to the present with good tolerance. The patient has no pain and continues without progression of disease after 13 month of treatment. For how long will she maintain this response, is the question.Rev Port Pneumol 2008; XIV (Supl 3): S71-S77 Palavras-chave: Adenocarcinoma do pulmão, derrame pleural, quimioterapia, erlotinib, qualidade de vida, sobrevivência, Key-words: Lung adenocarcinoma, pleural effusion, chemotherapy, erlotinib, quality of life, survival