Performance modeling of the sparse matrix-vector product via convolutional neural networks

[EN] Modeling the execution time of the sparse matrix-vector multiplication (SpMV) on a current CPU architecture is especially complex due to (i) irregular memory accesses; (ii) indirect memory referencing; and (iii) low arithmetic intensity. While analytical models may yield accurate estimates for the total number of cache hits/misses, they often fail to predict accurately the total execution time. In this paper, we depart from the analytic approach to instead leverage convolutional neural networks (CNNs) in order to provide an effective estimation of the performance of the SpMV operation. For this purpose, we present a high-level abstraction of the sparsity pattern of the problem matrix and propose a blockwise strategy to feed the CNN models by blocks of nonzero elements. The experimental evaluation on a representative subset of the matrices from the SuiteSparse Matrix collection demonstrates the robustness of the CNN models for predicting the SpMV performance on an Intel Haswell core. Furthermore, we show how to generalize the network models to other target architectures to estimate the performance of SpMV on an ARM A57 coreThis work was supported by project TIN2017-82972-R from the MINECO, Spain. Manuel F. Dolz was also supported by the Plan GenT project CDEIGENT/2018/014 from the Generalitat Valenciana, Spain. Maria Barreda was also supported by the POSDOC-A/2017/11 project from the Universitat Jaume IBarreda, M.; Dolz, MF.; Castaño Alvarez, MA.; Alonso-Jordá, P.; Quintana-Orti, ES. (2020). Performance modeling of the sparse matrix-vector product via convolutional neural networks. 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Perspectives on Smart Cities Strategies: Sketching a Framework and Testing First Uses

Many cities today claim to be or to become a "smart city". The approaches and public policy foci taken by cities differ depending on the particular context of each city, e.g., size, technology strategy, political system, current challenges and history. This paper is proposing a Smart City Strategy Framework in the form of a morphological box, describing elements relevant for a smart city strategy and their possible manifestations. The framework is based on a literature analysis and the contained elements are grouped into four dimensions: city context, governance, implementation, and infrastructure. The framework can be used to compare different cities in their approach towards becoming a smart city, and we claim that it also helps city planners to develop a strategy, guiding the evolutionary and continuous processes in their smart city. To validate the applicability of the framework, we used it in the drafting and structuring of a questionnaire to city representatives that served as preparation for an international stakeholder workshop on smart cities strategies in order to find out what strategies cities are following and what their current status is. The results of the questionnaire and the workshop hinted at common patterns for smart city strategies, and shows that maturity levels as well as cultural differences need to be taken more into account in future versions of the framework

Validación de un instrumento para medir el respeto de la autonomía del paciente en situación terminal durante la toma de decisiones médicas sobre el final de la vida

Antecedents: El respecte per l'autonomia de la persona consisteix a considerar-les preferències i valors de la persona malalta durant la presa de decisions sobre el tipus d'atenció que rep i és un element bioeticojurídic. No obstant això, no hi ha instruments validats sobre aquest fenomen que ajudin a aclarir la percepció del metge sobre aquest principi. Objectiu: Elaborar, validar mitjançant un judici d'experts i pilotejar per obtenir la consistència interna d'un instrument que avalua el nivell d'acord dels metges sobre els diferents elements que constitueixen el respecte per l'autonomia de la persona malalta en l'etapa terminal. Mètodes: Estudi transversal. Mètode de validació per judici de deu experts de Mèxic. L'instrument es va pilotejar en metges d'un hospital públic d'alta especialitat per determinar-ne la consistència interna. Resultats: Es va generar un instrument de 15 ítems amb un índex de validesa de contingut de 0.82 per a 10 experts. Va ser pilotejat en una mostra de 96 metges. S'obtingué un alfa de Cronbach de 0.694. Conclusions: Es va desenvolupar, validar i avaluar la consistència interna d'un qüestionari per mesurar el nivell d'acord de metges que atenen persones malaltes en etapa terminal amb relació als aspectes constitutius sobre el respecte de la seva autonomia. Se'n recomana l'aplicació en metges per corroborar-ne la utilitat i afavorir un diagnòstic situacional sobre la situació estudiada.Background: Respect for the autonomy of the person consists in considering the preferences and values of the sick person when making decisions about the type of care they receive and is a bioethical-legal element. However, there are no validated instruments on this phenomenon that help to clarify the physician's perception of this principle. Objective: To elaborate, validate through expert judgment and determine the internal consistency of an instrument that evaluates the level of agreement that the doctors have on the different elements that constitute respect for the autonomy of the terminally ill person. Methods: Cross-sectional study. The expert judgment validation method was used with a panel of ten experts from Mexico. The instrument was piloted in doctors of a highly specialized public hospital to determinate its internal consistency. Results: An instrument of 15 items was generated with a content validity index of 0.82 for 10 experts. It was piloted in a sample of 96 doctors (31.3% female and 68.7% male) and with an average age of 30 years. The Cronbach's alpha was 0.694. Conclusions: A questionnaire was developed to measure the level of agreement that the doctor who cares for terminally ill people has in relation to the constitutive aspects of respect for their autonomy. Based on the results of the validation and internal consistency, its application in medical populations is recommended to corroborate its usefulness and favor a simple situational diagnosis of the situation studied.Antecedentes: El respeto por la autonomía de la persona consiste en considerarlas preferencias y valores de la persona enferma durante la toma de decisions sobre el tipo de atención que recibe y es un elemento bioético-jurídico. Sin embargo, no existen instrumentos validados sobre este fenómeno que ayuden aclarificar la percepción del médico sobre este principio. Objetivo: Elaborar, validar mediante juicio de expertos y pilotear para obtener la consistencia interna de un instrumento que evalúa el nivel de acuerdo de los médicos sobre los diferentes elementos que constituyen el respeto por la  autonomía de la persona enferma en etapa terminal. Métodos: Estudio transversal. Método de validación por juicio de diez expertos de México. El instrumento se piloteó en médicos de un hospital público de alta especialidad para determinar la consistencia interna del mismo. Resultados: Se generó un instrumento de 15 ítems con un índice de validez de contenido de 0.82 para 10 expertos. Fue piloteado en una muestra de 96 médicos. Se obtuvo un alfa de Cronbach de 0.694. Conclusiones: Se desarrolló, validó y evaluó la consistencia interna de un cuestionario para medir el nivel de acuerdo de médicos que atienden a persones enfermas en etapa terminal con relación a los aspectos constitutivos sobre el respeto de su autonomía. Se recomienda su aplicación en médicos para corroborar su utilidad y favorecer un diagnóstico situacional sobre la situación estudiada

Safety and efficacy of ribociclib plus letrozole in patients with HR+, HER2– advanced breast cancer: Results from the Spanish sub-population of the phase 3b CompLEEment-1 trial

Background: Breast cancer is the most common malignancy and the second leading cause of cancer-related mortality in Spanish women. Ribociclib in combination with endocrine therapy (ET) has shown superiority in prolonging survival in patients with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) advanced breast cancer (ABC) vs. ET alone.Methods: CompLEEment-1 is a single-arm, open-label phase 3b trial evaluating ribociclib plus letrozole in a broad population of patients with HR+, HER2- ABC. The primary endpoints were safety and tolerability. Here we report data for Spanish patients enrolled in CompLEEment-1.Results: A total of 526 patients were evaluated (median follow-up: 26.97 months). Baseline characteristics showed a diverse population with a median age of 54 years. At study entry, 56.5% of patients had visceral metastases and 8.7% had received prior chemotherapy for advanced disease. Rates of all-grade and Grade >= 3 adverse events (AEs) were 99.0% and 76.2%, respectively; 21.3% of patients experienced a serious AE, and 15.8% of AEs led to treatment discontinuation. AEs of special interest of neutropenia, increased alanine aminotransferase, increased aspartate aminotransferase and QTcF prolongation occurred in 77.8%, 14.8%, 11.4% and 4.0% of patients, respectively. Patients aged >70 years experienced increased rates of all-grade and Grade >= 3 neutropenia and anemia. Efficacy results were consistent with the global study.Conclusions: Results from Spanish patients enrolled in CompLEEment-1 are consistent with global data showing efficacy and a manageable safety profile for ribociclib plus letrozole treatment in patients with HR+, HER2-ABC, including populations of interest (NCT02941926).Trial registration: ClinicalTrials.gov NCT0294192

Polycystic ovary syndrome: a complex condition with psychological, reproductive and metabolic manifestations that impacts on health across the lifespan

Polycystic ovary syndrome (PCOS) is of clinical and public health importance as it is very common, affecting up to one in five women of reproductive age. It has significant and diverse clinical implications including reproductive (infertility, hyperandrogenism, hirsutism), metabolic (insulin resistance, impaired glucose tolerance, type 2 diabetes mellitus, adverse cardiovascular risk profiles) and psychological features (increased anxiety, depression and worsened quality of life). Polycystic ovary syndrome is a heterogeneous condition and, as such, clinical and research agendas are broad and involve many disciplines. The phenotype varies widely depending on life stage, genotype, ethnicity and environmental factors including lifestyle and bodyweight. Importantly, PCOS has unique interactions with the ever increasing obesity prevalence worldwide as obesity-induced insulin resistance significantly exacerbates all the features of PCOS. Furthermore, it has clinical implications across the lifespan and is relevant to related family members with an increased risk for metabolic conditions reported in first-degree relatives. Therapy should focus on both the short and long-term reproductive, metabolic and psychological features. Given the aetiological role of insulin resistance and the impact of obesity on both hyperinsulinaemia and hyperandrogenism, multidisciplinary lifestyle improvement aimed at normalising insulin resistance, improving androgen status and aiding weight management is recognised as a crucial initial treatment strategy. Modest weight loss of 5% to 10% of initial body weight has been demonstrated to improve many of the features of PCOS. Management should focus on support, education, addressing psychological factors and strongly emphasising healthy lifestyle with targeted medical therapy as required. Monitoring and management of long-term metabolic complications is also an important part of routine clinical care. Comprehensive evidence-based guidelines are needed to aid early diagnosis, appropriate investigation, regular screening and treatment of this common condition. Whilst reproductive features of PCOS are well recognised and are covered here, this review focuses primarily on the less appreciated cardiometabolic and psychological features of PCOS

State of the Art Review: Emerging Therapies: The Use of Insulin Sensitizers in the Treatment of Adolescents with Polycystic Ovary Syndrome (PCOS)

PCOS, a heterogeneous disorder characterized by cystic ovarian morphology, androgen excess, and/or irregular periods, emerges during or shortly after puberty. Peri- and post-pubertal obesity, insulin resistance and consequent hyperinsulinemia are highly prevalent co-morbidities of PCOS and promote an ongoing state of excess androgen. Given the relationship of insulin to androgen excess, reduction of insulin secretion and/or improvement of its action at target tissues offer the possibility of improving the physical stigmata of androgen excess by correction of the reproductive dysfunction and preventing metabolic derangements from becoming entrenched. While lifestyle changes that concentrate on behavioral, dietary and exercise regimens should be considered as first line therapy for weight reduction and normalization of insulin levels in adolescents with PCOS, several therapeutic options are available and in wide use, including oral contraceptives, metformin, thiazolidenediones and spironolactone. Overwhelmingly, the data on the safety and efficacy of these medications derive from the adult PCOS literature. Despite the paucity of randomized control trials to adequately evaluate these modalities in adolescents, their use, particularly that of metformin, has gained popularity in the pediatric endocrine community. In this article, we present an overview of the use of insulin sensitizing medications in PCOS and review both the adult and (where available) adolescent literature, focusing specifically on the use of metformin in both mono- and combination therapy

Is diet partly responsible for differences in COVID-19 death rates between and within countries?

Correction: Volume: 10 Issue: 1 Article Number: 44 DOI: 10.1186/s13601-020-00351-w Published: OCT 26 2020Reported COVID-19 deaths in Germany are relatively low as compared to many European countries. Among the several explanations proposed, an early and large testing of the population was put forward. Most current debates on COVID-19 focus on the differences among countries, but little attention has been given to regional differences and diet. The low-death rate European countries (e.g. Austria, Baltic States, Czech Republic, Finland, Norway, Poland, Slovakia) have used different quarantine and/or confinement times and methods and none have performed as many early tests as Germany. Among other factors that may be significant are the dietary habits. It seems that some foods largely used in these countries may reduce angiotensin-converting enzyme activity or are anti-oxidants. Among the many possible areas of research, it might be important to understand diet and angiotensin-converting enzyme-2 (ACE2) levels in populations with different COVID-19 death rates since dietary interventions may be of great benefit.Peer reviewe

Cabbage and fermented vegetables : From death rate heterogeneity in countries to candidates for mitigation strategies of severe COVID-19

Large differences in COVID-19 death rates exist between countries and between regions of the same country. Some very low death rate countries such as Eastern Asia, Central Europe, or the Balkans have a common feature of eating large quantities of fermented foods. Although biases exist when examining ecological studies, fermented vegetables or cabbage have been associated with low death rates in European countries. SARS-CoV-2 binds to its receptor, the angiotensin-converting enzyme 2 (ACE2). As a result of SARS-CoV-2 binding, ACE2 downregulation enhances the angiotensin II receptor type 1 (AT(1)R) axis associated with oxidative stress. This leads to insulin resistance as well as lung and endothelial damage, two severe outcomes of COVID-19. The nuclear factor (erythroid-derived 2)-like 2 (Nrf2) is the most potent antioxidant in humans and can block in particular the AT(1)R axis. Cabbage contains precursors of sulforaphane, the most active natural activator of Nrf2. Fermented vegetables contain many lactobacilli, which are also potent Nrf2 activators. Three examples are: kimchi in Korea, westernized foods, and the slum paradox. It is proposed that fermented cabbage is a proof-of-concept of dietary manipulations that may enhance Nrf2-associated antioxidant effects, helpful in mitigating COVID-19 severity.Peer reviewe

Nrf2-interacting nutrients and COVID-19 : time for research to develop adaptation strategies

There are large between- and within-country variations in COVID-19 death rates. Some very low death rate settings such as Eastern Asia, Central Europe, the Balkans and Africa have a common feature of eating large quantities of fermented foods whose intake is associated with the activation of the Nrf2 (Nuclear factor (erythroid-derived 2)-like 2) anti-oxidant transcription factor. There are many Nrf2-interacting nutrients (berberine, curcumin, epigallocatechin gallate, genistein, quercetin, resveratrol, sulforaphane) that all act similarly to reduce insulin resistance, endothelial damage, lung injury and cytokine storm. They also act on the same mechanisms (mTOR: Mammalian target of rapamycin, PPAR gamma:Peroxisome proliferator-activated receptor, NF kappa B: Nuclear factor kappa B, ERK: Extracellular signal-regulated kinases and eIF2 alpha:Elongation initiation factor 2 alpha). They may as a result be important in mitigating the severity of COVID-19, acting through the endoplasmic reticulum stress or ACE-Angiotensin-II-AT(1)R axis (AT(1)R) pathway. Many Nrf2-interacting nutrients are also interacting with TRPA1 and/or TRPV1. Interestingly, geographical areas with very low COVID-19 mortality are those with the lowest prevalence of obesity (Sub-Saharan Africa and Asia). It is tempting to propose that Nrf2-interacting foods and nutrients can re-balance insulin resistance and have a significant effect on COVID-19 severity. It is therefore possible that the intake of these foods may restore an optimal natural balance for the Nrf2 pathway and may be of interest in the mitigation of COVID-19 severity