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A fisiologia coronariana tornou-se o padrão de tratamento para avaliar o significado funcional da doença aterosclerótica coronariana. Ela permite identificar isquemia miocárdica em nível de vaso, discriminar os padrões funcionais da doença aterosclerótica e orientar a necessidade de revascularização; complementar o planejamento da intervenção coronária percutânea e confirmar o sucesso funcional dessa última. Em uma edição anterior do Journal of Transcatheter Interventions, apresentamos uma revisão abrangente sobre o fluxo fracionado de reserva do miocárdio. Apesar do robusto corpo de evidências que apoiam seu uso, a aceitação clínica do fluxo fracionado de reserva é variável e excessivamente baixa em muitas áreas do mundo. O aumento percebido no tempo do procedimento, o uso de agentes hiperêmicos com seus correspondentes custos e desconforto do paciente, e a dificuldade de interpretação dos resultados em determinadas situações anatômicas contribuíram para a adoção limitada do método. A introdução do índice de fluxo instantâneo no período livre de ondas superou a maioria dessas limitações. Apoiada por uma validação técnica sólida e dados de desfechos clínicos, o índice de fluxo instantâneo no período livre de ondas recebeu as mesmas indicações clínicas que o fluxo fracionado de reserva nas recomendações mais recentes das diretrizes. Isso foi seguido pela introdução de outros índices pressóricos não hiperêmicos, já comercialmente disponíveis. Neste artigo, revisamos as bases fisiológicas que justificam o uso de índices pressóricos não hiperêmicos, sua validação técnica e clínica e dados de desfechos clínicos, além de discutirmos suas aplicações em situações anatômicas específicas, com exemplos de casos dos autores, sempre que aplicável.

Coronary physiology has become the standard of care to assess the functional significance of coronary atherosclerotic disease. It allows for identification of myocardial ischemia on a vessel level, discrimination of the functional patterns of atherosclerotic disease, guidance for the need of revascularization, complements the planning of percutaneous coronary intervention and verification of the functional success of percutaneous coronary intervention. On a previous issue of the Journal of Transcatheter Interventions, we presented a comprehensive review about fractional flow reserve. Despite the robust body of evidence supporting its use, the clinical use of fractional flow reserve is variable, and unreasonably low in many areas around the globe. The perceived increase in procedure time, the use of hyperemic agents with its related costs and patient discomfort, and difficulty in interpreting results in certain anatomical scenarios have contributed to the limited adoption of fractional flow reserve. The introduction of instantaneous wave-free ratio overcame most of these limitations. Supported by sound technical validation, and clinical outcomes data, instantaneous wave-free ratio received the same clinical indications as fractional flow reserve in the most recent guidelines recommendations. This was followed by the introduction of other non- hyperemic pressure ratios for commercial use. In the current manuscript we review the physiological basis that supports the use of non-hyperemic pressure ratios, their technical and clinical validation, clinical outcomes data, and discuss its applications on specific anatomic scenarios, with examples of cases from the authors, whenever applicable.

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INTRODUÇÃO: A proporção de pacientes submetidos à cinecoronariografia eletiva que necessitam complementação diagnóstica adicional para a tomada de decisão terapêutica é desconhecida no Brasil, assim como o seu manejo na prática clínica atual. OBJETIVOS: Avaliar a prevalência de estenoses coronárias intermediárias (40-70%) em pacientes submetidos à cinecoronariografia, e seu manejo atual nos diferentes níveis de suplementação de saúde no Brasil. MÉTODOS: Registro prospectivo, multicêntrico, de braço único, em que foram incluídos todos os pacientes consecutivos submetidos à cinecoronariografia entre JUN/21 e SET/21 em 5 hospitais de referência em Cardiologia no Brasil (2 públicos e 3 privados). O desfecho primário foi a ocorrência de eventos cardiovasculares adversos maiores (ECAM: morte, infarto, re-internação por recorrência de angina e revascularização não planejada da lesão alvo). RESULTADOS: 503 pacientes foram incluídos. A média das idades foi 63±11 anos, 69,8% são homens, 35,6% são diabéticos, e 44,1% se apresentaram com síndrome estável. Menos da metade (41,7%) possuíam alguma avaliação funcional prévia à cinecoronariografia. Algum grau de estenose coronária foi documentado em 421 pacientes (84%), dos quais 177 (42%) apresentavam redução luminal entre 40-70%. As informações clínicas e angiográficas foram consideradas insuficientes para tomada de decisão em 223 pacientes (44.3%). Destes, fisiologia invasiva foi realizada no momento da cinecoronariografia em 27 pacientes (12,1%), imagem intravascular em 5 (2,2%), avaliação funcional não invasiva solicitada para 32 (14,3%) e 161 (72,2%) liberados sem qualquer avaliação adicional. No seguimento médio de 180±68 dias, 148 pacientes foram contatados, e 18,9% apresentaram ECAM. Dentre os 148 pacientes sem resolução diagnóstica durante a cinecoronariografia, 28 pacientes (18,9%) permaneceram sintomáticos e necessitaram atendimento médico posterior, 17 (11,5%) foram hospitalizados, 6 (4,1%) sofreram revascularização não planejada, e 8 (5,4%) sofreram infarto fatal. CONCLUSÕES: Dentre os pacientes submetidos à cinecoronariografia, proporção não desprezível possui estenoses coronárias para as quais avaliação adicional é necessária para a tomada de decisão. A grande maioria destes pacientes é liberada sem qualquer investigação adicional. O tempo para complementação diagnóstica impacta na ocorrência de desfechos clínicos e qualidade de vida

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A avaliação fisiológica invasiva da circulação coronariana emergiu nos últimos anos como uma abordagem diagnóstica valiosa no manejo de pacientes com síndrome coronariana crônica, contornando limitações importantes como avaliar função a partir da anatomia e a baixa resolução espacial associada à angiografia ou testes não invasivos. O valor das medidas de fluxo hiperêmico para estimar a relevância funcional das estenoses coronárias é suportado por um grande número de estudos. O objetivo do presente artigo é rever as principais bases fisiológicas, aplicações clínicas e limitações do fluxo fracionado de reserva do miocárdio, o principal índice utilizado na avaliação funcional invasiva da circulação coronariana.

Invasive physiological assessment of the coronary circulation has emerged in recent years as a valuable diagnostic approach in the management of patients with chronic coronary syndrome, overcoming important limitations such as evaluating function from the anatomy and the low spatial resolution associated with angiography or non-invasive tests. The value of hyperemic flow measurements to estimate the functional relevance of coronary stenoses is supported by many studies. The aim of this paper is to review the physiological bases, clinical applications and limitations of myocardial fractional flow reserve, the main index used in the invasive functional assessment of the coronary circulation.

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We develop a generalizable AI-driven workflow that leverages heterogeneous HPC resources to explore the time-dependent dynamics of molecular systems. We use this workflow to investigate the mechanisms of infectivity of the SARS-CoV-2 spike protein, the main viral infection machinery. Our workflow enables more efficient investigation of spike dynamics in a variety of complex environments, including within a complete SARS-CoV-2 viral envelope simulation, which contains 305 million atoms and shows strong scaling on ORNL Summit using NAMD. We present several novel scientific discoveries, including the elucidation of the spike's full glycan shield, the role of spike glycans in modulating the infectivity of the virus, and the characterization of the flexible interactions between the spike and the human ACE2 receptor. We also demonstrate how AI can accelerate conformational sampling across different systems and pave the way for the future application of such methods to additional studies in SARS-CoV-2 and other molecular systems.

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We develop a generalizable AI-driven workflow that leverages heterogeneous HPC resources to explore the time-dependent dynamics of molecular systems. We use this workflow to investigate the mechanisms of infectivity of the SARS-CoV-2 spike protein, the main viral infection machinery. Our workflow enables more efficient investigation of spike dynamics in a variety of complex environments, including within a complete SARS-CoV-2 viral envelope simulation, which contains 305 million atoms and shows strong scaling on ORNL Summit using NAMD. We present several novel scientific discoveries, including the elucidation of the spike's full glycan shield, the role of spike glycans in modulating the infectivity of the virus, and the characterization of the flexible interactions between the spike and the human ACE2 receptor. We also demonstrate how AI can accelerate conformational sampling across different systems and pave the way for the future application of such methods to additional studies in SARS-CoV-2 and other molecular systems.

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Purification of the density matrix methods should be employed when dealing with complex chemical systems containing many atoms. The running times for these methods scale linearly with the number of atoms if we consider the sparsity from the density matrix. Since the efficiency expected from those methods is closely tied to the underlying parallel implementations of the linear algebra operations (e.g., P2 = P × P), we proposed a central processing unit (CPU) and graphics processing unit (GPU) parallel matrix-matrix multiplication in SVBR (symmetrical variable block row) format for energy calculations through the SP2 algorithm. This algorithm was inserted in MOPAC's MOZYME method, using the original LMO Fock matrix assembly, and the atomic integral calculation implemented on it. Correctness and performance tests show that the implemented SP2 is accurate and fast, as the GPU is able to achieve speedups up to 40 times for a water cluster system with 42,312 orbitals running in one NVIDIA K40 GPU card compared to the single-threaded version. The GPU-accelerated SP2 algorithm using the MOZYME LMO framework enables the calculations of semiempirical wavefunction with stricter SCF criteria for localized charged molecular systems, as well as the single-point energies of molecules with more than 100.000 LMO orbitals in less than 1 h. Graphical abstract Parallel CPU and GPU purification algorithms for electronic structure calculations were implemented in MOPAC's MOZYME method. Some matrices in these calculations, e.g., electron density P, are compressed, and the developed linear algebra operations deal with non-zero entries only. We employed the NVIDIA/CUDA platform to develop GPU algorithms, and accelerations up to 40 times for larger systems were achieved.

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Seed priming is widely used in commercial seeds and its main function is to accelerate and synchronize seed germination. Undesirably, primed seeds show reduced longevity and treatments like heat shock have been shown to improve longevity in primed seeds. Nonetheless, the effect of heat shock treatment on primed seeds at the mRNA level is not known. Thus, the aim of this work was to investigate the effect of heat shock treatment on the longevity of primed tomato (Solanum lycopersicum) seeds at the physiological and transcriptome levels. Tomato seeds were primed and dried (control). Alternatively, primed seeds were subjected to heat shock treatment (38 °C/32 % relative humidity) before drying. Germination, vigor and longevity were evaluated. Transcriptome analysis was performed by RNA sequencing (RNA-seq) from biological samples collected immediately after priming and another samples collected from primed seeds followed by the heat shock treatments. The gene expression was validated by quantitative real time PCR (RT-qPCR). We showed that applying heat shock treatment after priming increased germination speed, enhanced seed longevity and preserved the vigor during storage of primed tomato seeds. Through transcriptome analysis, 368 differentially expressed genes were identified, from which 298 genes were up-regulated and 70 were down-regulated. We showed the increase of mRNA levels of HEAT SHOCK FACTOR-like and HEAT SHOCK PROTEIN-like chaperone genes, suggesting the involvement of the proteins coded by these transcripts in the enhancement of longevity in primed tomato seeds. The heat shock treatment after priming enhances and preserves the vigor of tomato primed seeds during storage. In addition, improves seed longevity through the increase in the expression of transcripts related to protection by response to stress.

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Harnessing the power of graphics processing units (GPUs) to accelerate molecular dynamics (MD) simulations in the context of free-energy calculations has been a longstanding effort toward the development of versatile, high-performance MD engines. We report a new GPU-based implementation in NAMD of free-energy perturbation (FEP), one of the oldest, most popular importance-sampling approaches for the determination of free-energy differences that underlie alchemical transformations. Compared to the CPU implementation available since 2001 in NAMD, our benchmarks indicate that the new implementation of FEP in traditional GPU code is about four times faster, without any noticeable loss of accuracy, thereby paving the way toward more affordable free-energy calculations on large biological objects. Moreover, we have extended this new FEP implementation to a code path highly optimized for a single-GPU node, which proves to be up to nearly 30 times faster than the CPU implementation. Through optimized GPU performance, the present developments provide the community with a cost-effective solution for conducting FEP calculations. The new FEP-enabled code has been released with NAMD 3.0.

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NAMDis a molecular dynamics program designed for high-performance simulations of very large biological objects on CPU- and GPU-based architectures. NAMD offers scalable performance on petascale parallel supercomputers consisting of hundreds of thousands of cores, as well as on inexpensive commodity clusters commonly found in academic environments. It is written in C++ and leans on Charm++ parallel objects for optimal performance on low-latency architectures. NAMD is a versatile, multipurpose code that gathers state-of-the-art algorithms to carry out simulations in apt thermodynamic ensembles, using the widely popular CHARMM, AMBER, OPLS, and GROMOS biomolecular force fields. Here, we review the main features of NAMD that allow both equilibrium and enhanced-sampling molecular dynamics simulations with numerical efficiency. We describe the underlying concepts utilized by NAMD and their implementation, most notably for handling long-range electrostatics; controlling the temperature, pressure, and pH; applying external potentials on tailored grids; leveraging massively parallel resources in multiple-copy simulations; and hybrid quantum-mechanical/molecular-mechanical descriptions. We detail the variety of options offered by NAMD for enhanced-sampling simulations aimed at determining free-energy differences of either alchemical or geometrical transformations and outline their applicability to specific problems. Last, we discuss the roadmap for the development of NAMD and our current efforts toward achieving optimal performance on GPU-based architectures, for pushing back the limitations that have prevented biologically realistic billion-atom objects to be fruitfully simulated, and for making large-scale simulations less expensive and easier to set up, run, and analyze. NAMD is distributed free of charge with its source code at www.ks.uiuc.edu.

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O presente estudo caracteriza-se como uma pesquisa bibliográfica objetivada a compreender o sentido dado à dinâmica curricular a partir das nuances sócio­político­culturais que se protagonizaram nos Estados Unidos da América durante o primeiro meado do século passado. Configura-se em cinco tópicos consequentes, a partir de um espectro histórico, que discorrem desde o processo de institucionalização da educação em massa, fomentador do surgimento da Teoria Curricular Tradicional (primórdios do século passado), até o momento de crise da proposta curricular de Tyler (meados do século XX). Também é alvo de especulação deste estudo, no decorrer do trajeto histórico considerado, evidenciar as contribuições de Dewey e Bobbit frente à Teoria Tradicional do Currículo. O esforço de síntese paira sobre o desfalecimento desta perspectiva curricular frente à necessidade humana pela reconfiguração do abarrotado cenário educacional norte-americano.(AU)

Este estudio se caracteriza como una investigación bibliográfica objetivada a comprender el sentido dado a la dinámica curricular a partir de los matices socio-político-culturales que se protagonizaron en los Estados Unidos de América durante el primer mediado del siglo pasado. Se configura en cinco tópicos consecuentes, a partir de un espectro histórico, que discurren desde el proceso de institucionalización de la educación masiva, fomentador del surgimiento de la Teoría Curricular Tradicional (primordios del siglo pasado), hasta el momento de crisis de la propuesta curricular de Tyler (mediados del siglo XX). También es objeto de especulación de este estudio, en el curso del trayecto histórico considerado, evidenciar las contribuciones de Dewey y Bobbit frente a la Teoría Tradicional del Currículo. El esfuerzo de síntesis sobre el desfase de esta perspectiva curricular frente a la necesidad humana por la reconfiguración del abarrotado escenario educativo norteamericano. Palabras clave: Historia del currículo; teoría curricular; pedagogía tradicional.(AU)

This study is characterized as a bibliographical research aimed at understanding the meaning given to curricular dynamics from the socio-political-cultural nuances that perform a key role in the United States of America during the last century first half. It is based on five sequential topics that range from the institutionalization process of mass education, fomenting the Traditional Curricular Theory emergence (early in the last century), until the Tyler curricular proposal crisis (mid twentieth century). It is also speculation in this study, during the historical course considered, to highlight the Dewey and Bobbit contributions to the Traditional Theory of Curriculum. The synthesis effort hovers on the fading of this curricular perspective in front of the human need for the educational scene North American reconfiguration.(AU)

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Resumo: A presente investigação, cuja tipologia por delineamento é designativa de uma Pesquisa Bibliográfica, debruça-se sobre a produção científica relativa às Diretrizes Curriculares para a Educação Física (DCNEF), objetivando apreender as circunstâncias históricas que estruturam o embate existente no campo da formação e, por conseguinte, intervenção profissional nesta área. Utiliza-se a base dados P@rthenon para levantamento da produção e, posteriormente, identifica 23 artigos, publicados em diversificados instantes e periódicos, classificados em três condicionantes: a) Elaboração das DCNEF; b) Resolução CNE/CES nº 07/2004; c) Minuta de 2015. O esforço de síntese identifica que passa a existir, entre os dois últimos condicionantes, tanto uma tendência de readequação da divergência de posicionamentos, como também uma lacuna evidenciada na produção científica ante o número restrito de pesquisas que, após a promulgação da Minuta de 2015, vislumbram subterfúgio ao direcionamento dado a formação e intervenção na área desde as duas últimas décadas.

Abstract: This study, whose typology is Bibliographic Research, addresses scientific work related to Curricular Guidelines for Physical Education (known as DCNEF), aiming to apprehend the historical circumstances that structure the debate existing in the training field and, consequently, professional intervention in the area. The survey was conducted on the P@rthenon database and found 23 articles published at various times and journals, which were selected and classified according to three conditions: a) creation of DCNEF; b) CNE/CES Resolution 07/2004; c) 2015 Minute. The synthesis effort finds (1) a tendency to readjust differences in stances between the last two conditions and (2) a gap in scientific work as a result of the low number of studies that after 2015 Minute find deviation regarding the direction given to training and intervention in the area since the last two decades.

Resumen: La presente investigación, cuya tipología por delineamiento es designativa de una Investigación Bibliográfica, explora la producción científica relativa a las DCNEF, objetivando entender las circunstancias históricas que estructuran el embate existente en el campo de la formación y, consecuentemente, intervención profesional en esta área. Se utiliza la base de datos P@arthenon para hacer el levantamiento de la producción y, posteriormente, son identificados 23 artículos, publicados en diversas fechas y periódicos, que son clasificados en tres condicionantes: a) Elaboración de las DCNEF; b) Resolución CNE/CES nº 07/2004; c) Minuta de 2015. El esfuerzo de síntesis identifica que pasa a existir, entre los dos últimos condicionantes, una tendencia de readecuación de la divergencia de posicionamientos, además de constatar una laguna evidenciada en la producción científica, al haber un número restricto de investigaciones que, después de la Minuta de 2015, vislumbran subterfugio a la dirección dada a la formación e intervención en el área en las últimas dos décadas.

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A ótica gramsciana indaga como uma determinada concepção de mundo se converte em hegemonia. Sua suspeita é que as revoluções burguesas criaram as condições para o surgimento de uma nova matriz produtiva, ao mesmo tempo em que inauguraram um poderoso sistema de educação que se desenvolve pela constante reforma das organizações culturais modernas. O presente estudo busca compreender, diante dessa tese, o lugar da Educação Física no atual momento de contrarreforma do Ensino Médio brasileiro, para tanto examina a participação do esporte em sua versão performance na educação do sujeito coletivo moderno, bem como a resistência, por meio da crítica radical, a esse procedimento racional. Orienta-se pelo materialismo histórico dialético, com tipologia compreensiva e bibliográfica.

A gramscian optic asks how a world certain conception becomes hegemony. His suspicion is bourgeois revolutions created the conditions for the new productive matrix emergence, at the same time they inaugurated a new education system that is developed by the constant modern cultural organizations reform. This study sought to understand, through this thesis, the Physi-cal Education's place in the current Brazilian High School counteracting moment, therefore ascertains the participation of the sport, in its performance version, in the modern collective subject education, as well as the resistance, through radical criticism, to this rational proce-dure. It's guided by Dialectical Historical Materialism, with a comprehensive and biblio-graphical typology.

La óptica gramsciana indaga como una determinada concepción del mundo se convierte en hegemonía. Su sospecha es que las revoluciones burguesas crearon las condiciones para el surgimiento de una nueva matriz productiva, al mismo tiempo en que inauguraron un podero-so sistema de educación que se desarrolla por la constante reforma de las organizaciones cul-turales modernas. El presente estudio busca comprender, delante de esa tese, el lugar de la Educación Física en el actual versión performance en la educación del sujeto colectivo mo-derno, bien como la resistencia, por medio de la crítica radical, a ese procedimiento racional. Se orienta por el Materialismo Histórico Dialéctico con tipología comprensiva y bibliográfica.

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Hybrid methods that combine quantum mechanics (QM) and molecular mechanics (MM) can be applied to studies of reaction mechanisms in locations ranging from active sites of small enzymes to multiple sites in large bioenergetic complexes. By combining the widely used molecular dynamics and visualization programs NAMD and VMD with the quantum chemistry packages ORCA and MOPAC, we created an integrated, comprehensive, customizable, and easy-to-use suite (http://www.ks.uiuc.edu/Research/qmmm). Through the QwikMD interface, setup, execution, visualization, and analysis are streamlined for all levels of expertise.

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Background: By observing the high prevalence of failures in the surgical treatment of myocardial revascularization (MR), with the use of the Left Internal Thoracic Artery (LITA) as a graft, evidenced by the international literature, it was sought to demonstrate the prevalence of lesions that would not allow the use of LITA as a graft in myocardial revascularization surgery, with possible alteration in the surgical management performed by the cardiac surgeon, and reduction of the morbimortality of these patients. Objectives: To evaluate the prevalence of atherosclerotic lesions of the LITA, through selective preoperative angiography, in patients submitted to coronary angiography and indicated for myocardial revascularization. We also analyzed other lesions that made the use of LITA unfeasible as a main graft in cases of myocardial revascularization surgery (MRS). Methods: This was a cross-sectional, prevalence study that evaluated, through selective angiography, the LITA of 39 patients with a median age of 63 years, submitted to coronary angiography, with indication of Coronary Artery Bypass Graft (CABG). Categorical variables were compared by chi-square test and Fisher's exact test. The single continuous variable, age, was tested for normality by the Kolmogorov-Smirnov test, described in median (P25; P75) and the groups compared with the Mann-Whitney test. The level of statistical significance adopted was p < 0.05. The analyzes were performed in SPSS ® software version 20. Results: It was identified the presence of 7.7% of disorders in the LITA that made it unfeasible to be used. In all of the patients there was no specific symptomatology evidencing the lesion. No variable was shown as a predictor for the occurrence of the outcomes. Conclusion: The prevalence of the lesions found in the study was significant, indicating that a preoperative evaluation of LITA could bring future benefits to the patients submitted to CABG

Fundamento: Pela observação da alta prevalência de falhas no tratamento cirúrgico da revascularização do miocárdio (RM), com o uso da Artéria Torácica Interna Esquerda (ATIE) como enxerto, evidenciadas pela literatura internacional, buscou-se demonstrar a prevalência de lesões que inviabilizem o uso da ATIE como enxerto na cirurgia de revascularização do miocárdio, com possível alteração na conduta cirúrgica tomada pelo cirurgião cardíaco, e redução da morbimortalidade destes pacientes. Objetivos: Avaliar a prevalência de lesões ateroscleróticas da ATIE, por meio da angiografia seletiva, pré - operatória, em pacientes submetidos à cinecoronariografia e com indicação de revascularização cirúrgica do miocárdio. Também foram analisadas outras lesões que inviabilizam o uso da ATIE como enxerto principal em casos de necessidade da cirurgia de revascularização do miocárdio (CRM). Métodos: Estudo analítico, transversal, de prevalência, que avaliou por meio da angiografia seletiva, a ATIE de 39 pacientes com mediana de idade de 63 anos, submetidos ao exame de cinecoronariografia, com indicação de CRM. As variáveis categóricas foram comparadas pelo teste do qui-quadrado e exato de Fisher. A única variável contínua, a idade, foi testada para normalidade pelo teste de Kolmogorov-Smirnov, descrita em mediana (P25; P75) e os grupos comparados com teste de Mann-Whitney. O nível de significância estatística adotado foi p < 0,05. As análises foram realizadas no software SPSS ® versão 20. Resultados: Foi identificada a presença de 7,7% de alterações na ATIE que inviabilizam sua utilização. Em todos os pacientes inexistiu a presença de qualquer sintomatologia especifica que evidencia a lesão. Nenhuma variável se mostrou como fator preditor para ocorrência dos desfechos. Conclusão: A prevalência das lesões encontradas no estudo mostrou-se significativa, indicando que uma avaliação pré-operatória de ATIE possa trazer benefícios futuros aos pacientes submetido à CRM

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INTRODUCTION: In systems biology, where a main goal is acquiring knowledge of biological systems, one of the challenges is inferring biochemical interactions from different molecular entities such as metabolites. In this area, the metabolome possesses a unique place for reflecting "true exposure" by being sensitive to variation coming from genetics, time, and environmental stimuli. While influenced by many different reactions, often the research interest needs to be focused on variation coming from a certain source, i.e. a certain covariable [Formula: see text]. OBJECTIVE: Here, we use network analysis methods to recover a set of metabolite relationships, by finding metabolites sharing a similar relation to [Formula: see text]. Metabolite values are based on information coming from individuals' [Formula: see text] status which might interact with other covariables. METHODS: Alternative to using the original metabolite values, the total information is decomposed by utilizing a linear regression model and the part relevant to [Formula: see text] is further used. For two datasets, two different network estimation methods are considered. The first is weighted gene co-expression network analysis based on correlation coefficients. The second method is graphical LASSO based on partial correlations. RESULTS: We observed that when using the parts related to the specific covariable of interest, resulting estimated networks display higher interconnectedness. Additionally, several groups of biologically associated metabolites (very large density lipoproteins, lipoproteins, etc.) were identified in the human data example. CONCLUSIONS: This work demonstrates how information on the study design can be incorporated to estimate metabolite networks. As a result, sets of interconnected metabolites can be clustered together with respect to their relation to a covariable of interest.

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Desiccation tolerance is common in seeds and various other organisms, but only a few angiosperm species possess vegetative desiccation tolerance. These 'resurrection species' may serve as ideal models for the ultimate design of crops with enhanced drought tolerance. To understand the molecular and genetic mechanisms enabling vegetative desiccation tolerance, we produced a high-quality whole-genome sequence for the resurrection plant Xerophyta viscosa and assessed transcriptome changes during its dehydration. Data revealed induction of transcripts typically associated with desiccation tolerance in seeds and involvement of orthologues of ABI3 and ABI5, both key regulators of seed maturation. Dehydration resulted in both increased, but predominantly reduced, transcript abundance of genomic 'clusters of desiccation-associated genes' (CoDAGs), reflecting the cessation of growth that allows for the expression of desiccation tolerance. Vegetative desiccation tolerance in X. viscosa was found to be uncoupled from drought-induced senescence. We provide strong support for the hypothesis that vegetative desiccation tolerance arose by redirection of genetic information from desiccation-tolerant seeds.

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A failing intracardiac device is traditionally addressed by open-heart surgery. Surgical explantation of the device, although a simple procedure, carries risks that some patients are not able or willing to cope with. Thus, a nonsurgical option seems desirable in selected cases. We report on four cases of early malfunction of the Polyvinyl Alcohol membrane of Ultrasept II™ CARDIA ASD devices. In all cases, transthoracic echo (TTE) surveillance 4-6 months after the index procedure, depicted significant left-to-right atrial shunts through the center portion of the devices. A second nitinol double disk device with a connecting pin (Lifetech CERA™ Multifenestrated ASD device) was implanted over the CARDIA devices, with excellent results. All procedures were uneventful and all patients are asymptomatic with no residual shunts, in short-term follow-up. This device-in-device technique prevents surgical explantation of failing ASD devices, and may become a less invasive option in selected patients. © 2016 Wiley Periodicals, Inc.

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MAIN CONCLUSION: Besides being an important model to study desiccation tolerance, the induction of desiccation tolerance in germinated seeds may also play an ecological role in seedling establishment. Desiccation tolerance (DT) is the ability of certain organisms to survive extreme water losses without accumulation of lethal damage. This was a key feature in the conquering of dry land and is currently found in all taxa including bacteria, fungi, roundworms and plants. Not surprisingly, studies in various fields have been performed to unravel this intriguing phenomenon. In flowering plants, DT is rare in whole plants (vegetative tissues), yet is common in seeds. In this review, we present our current understanding of the evolution of DT in plants. We focus on the acquisition of DT in seeds and the subsequent loss during and after germination by highlighting and comparing research in two model plants Medicago truncatula and Arabidopsis thaliana. Finally, we discuss the ability of seeds to re-establish DT during post-germination, the possible ecological meaning of this phenomenon, and the hypothesis that DT, in combination with dormancy, optimizes seedling establishment.

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During germination, orthodox seeds lose their desiccation tolerance (DT) and become sensitive to extreme drying. Yet, DT can be rescued, in a well-defined developmental window, by the application of a mild osmotic stress before dehydration. A role for abscisic acid (ABA) has been implicated in this stress response and in DT re-establishment. However, the path from the sensing of an osmotic cue and its signaling to DT re-establishment is still largely unknown. Analyses of DT, ABA sensitivity, ABA content and gene expression were performed in desiccation-sensitive (DS) and desiccation-tolerant Arabidopsis thaliana seeds. Furthermore, loss and re-establishment of DT in germinated Arabidopsis seeds was studied in ABA-deficient and ABA-insensitive mutants. We demonstrate that the developmental window in which DT can be re-established correlates strongly with the window in which ABA sensitivity is still present. Using ABA biosynthesis and signaling mutants, we show that this hormone plays a key role in DT re-establishment. Surprisingly, re-establishment of DT depends on the modulation of ABA sensitivity rather than enhanced ABA content. In addition, the evaluation of several ABA-insensitive mutants, which can still produce normal desiccation-tolerant seeds, but are impaired in the re-establishment of DT, shows that the acquisition of DT during seed development is genetically different from its re-establishment during germination.

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In this study, we present some modifications in the semiempirical quantum chemistry MOPAC2009 code that accelerate single-point energy calculations (1SCF) of medium-size (up to 2500 atoms) molecular systems using GPU coprocessors and multithreaded shared-memory CPUs. Our modifications consisted of using a combination of highly optimized linear algebra libraries for both CPU (LAPACK and BLAS from Intel MKL) and GPU (MAGMA and CUBLAS) to hasten time-consuming parts of MOPAC such as the pseudodiagonalization, full diagonalization, and density matrix assembling. We have shown that it is possible to obtain large speedups just by using CPU serial linear algebra libraries in the MOPAC code. As a special case, we show a speedup of up to 14 times for a methanol simulation box containing 2400 atoms and 4800 basis functions, with even greater gains in performance when using multithreaded CPUs (2.1 times in relation to the single-threaded CPU code using linear algebra libraries) and GPUs (3.8 times). This degree of acceleration opens new perspectives for modeling larger structures which appear in inorganic chemistry (such as zeolites and MOFs), biochemistry (such as polysaccharides, small proteins, and DNA fragments), and materials science (such as nanotubes and fullerenes). In addition, we believe that this parallel (GPU-GPU) MOPAC code will make it feasible to use semiempirical methods in lengthy molecular simulations using both hybrid QM/MM and QM/QM potentials.