956 research outputs found

    A Bibliometric Overview of the International Journal of Interactive Multimedia and Artificial Intelligence

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    The International Journal of Interactive Multimedia and Artificial Intelligence (IJIMAI) published its first issue ten years ago. Currently, IJIMAI is indexed in the important database Emerging Sources Citation Index. This paper aims to identify, through a mapping of science, those most relevant aspects of the structure of publications made during the first 10 years of IJIMAI. Using VOSviewer software, the structural maps of the IJIMAI publications are analysed according to techniques such as bibliographic coupling, co-citations and cooccurrence of keywords. In addition, the evolution of the publications, citations and an analysis of the most cited papers of the journal are presented. The results show that IJIMAI has experienced a remarkable growth of both publications and citations in the last five years. We also observe that IJIMAI does not only capture the attention of the Spanish scientific community, but also of emerging countries such as India and Iran and emerging Latin American countries such as Colombia. With a such increasing behaviour, it is expected in the coming years that IJIMAI will position itself among the best journals with similar scientific scope

    Quid: observatorio de medios

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    En la primera parte de la obra se aborda el tema de medios y las elecciones de 2009; en la segunda, la transparencia y la rendición de cuentas, y en la tercera parte los medios de comunicación y el periodismo. Al final se presentan sembalnzas de Rigo Mora, Álvaro González de Mendoza y David “el Negro” Guerrero, quienes desde el cine y la radiodifusión, dejaron momentos memorables a la comunidad tapatía.ITESO, A.C

    Enantiopure 4‐oxazolin‐2‐ones and 4‐methylene‐2‐oxazolidinones as chiral building blocks in a divergent asymmetric synthesis of heterocycles

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    En este trabajo se describe la reactividad de las oxazolidin-2-onas en un ambiente quiral obteniéndose resultados novedosos, los cuales se describen extensamente.Enantiopure 3‐((R)‐ and 3‐((S)‐1‐phenylethyl)‐4‐oxazoline‐2‐ones were evaluated as chiral building blocks for the divergent construction of heterocycles with stereogenic quaternary centers. The N‐(R)‐ or N‐(S)‐1‐phenylethyl group of these compounds proved to be an efficient chiral auxiliary for the asymmetric induction of the 4‐ and 5‐positions of the 4‐oxazolin‐2‐one ring through thermal and MW‐promoted nucleophilic conjugated addition to Michael acceptors and alkyl halides. The resulting adducts were transformed via a cascade process into fused six‐membered carbo‐ and heterocycles. The structure of the reaction products depended on the electrophiles and reaction conditions used. Alternative isomeric 4‐methylene‐2‐oxazolidinones served as chiral precursors for a versatile and divergent approach to highly substituted cyclic carbamates. DFT quantum calculations showed that the formation of bicyclic pyranyl compounds was generated by a diastereoselective concerted hetero‐Diels‐Alder cycloaddition.Instituto Politécnico Nacional, Secretaria de Investigación y Estudios Avanzados de la Universidad Autónoma del Estado de México, Universidad de Guanajuato y CONACYT

    Diagnóstico y tratamiento del cáncer de mama HER2+: Guía de Práctica Clínica de la Sociedad Peruana de Cancerología

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    Introduction. In Peru, breast cancer represents the most common type of cancer in women and the sixth most lethal type of cancer in the general population. Overexpression of the epidermal growth factor receptor (HER2 +) occurs in 20% to 30% of breast cancers, and is associated with more aggressive tumors, with greater recurrence and greater mortality. Objective. Prepare a set of evidence-based recommendations for the diagnosis and treatment of HER2 + breast cancer, in order to help reduce mortality, disease progression and improve quality of life. Methods. A panel of clinical specialists and methodologists was formed, who identified relevant clinical questions about the diagnosis and treatment of HER2 + breast cancer. A systematic search for CPGs was carried out in Medline (PubMed), and in developing and compiling agencies. For the formulation of recommendations, the panel of specialists discussed the evidence and elements of the context of implementation of the recommendation, following the methodology proposed by the Ministry of Health of Peru. Results. Nine clinical questions were prioritized. A total of 25 clinical recommendations were made. Conclusions. An evidence-based CPG was developed through a systematic, rigorous and transparent process developed by a multidisciplinary team.Introducción. En Perú, el cáncer de mama representa el tipo de cáncer más frecuente en mujeres y el sexto tipo de cáncer más letal en la población general. La sobreexpresión del receptor del factor de crecimiento epidérmico (HER2+) ocurre en 20% a 30% de los cánceres de mama, y se asocia con tumores más agresivos, con mayor recurrencia y mayor mortalidad. Objetivo. Elaborar un conjunto de recomendaciones basadas en evidencias para el diagnóstico y tratamiento del cáncer de mama HER2+, con la finalidad de contribuir a reducir la mortalidad, progresión de la enfermedad y mejorar la calidad de vida. Métodos. Se conformó un panel de especialistas clínicos y metodólogos, quienes identificaron preguntas clínicas relevantes sobre el diagnóstico y tratamiento del cáncer de mama HER2+. Se desarrolló una búsqueda sistemática de GPC en Medline (PubMed), y en organismos elaboradores y recopiladores. Para la formulación de recomendaciones, el panel de especialistas discutió la evidencia y elementos del contexto de implementación de la recomendación, siguiendo la metodología propuesta por el Ministerio de Salud del Perú. Resultados. Se priorizó nueve preguntas clínicas. Se formuló un total de 25 recomendaciones clínicas. Conclusiones. Se elaboró una GPC basada en evidencias, a través de un proceso sistemático, riguroso y transparente desarrollado por un equipo multidisciplinario.&nbsp

    Impacto y evaluación del riesgo en la deuda pensional contingente de Colombia

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    Este estudio esclarece los conceptos de deuda pública cierta, respecto a la deuda contingente e identifica su impacto en la sostenibilidad de las finanzas públicas del país. Los razonamientos que se hacen acerca de la sostenibilidad de la deuda es decir, si la deuda de un país puede ser otorgada sin una gran corrección futura en el balance de ingresos y gastos, se dirigen a determinar en qué momento es apropiado para un país refinanciar y sí una reestructuración de la deuda puede ser necesaria. En la parte siguiente se realiza un análisis sobre la incertidumbre alrededor de las proyecciones de la deuda y el servicio de la deuda, la cual se relaciona con los derechos contingentes, tales como los definidos con las garantías explícitas implícitas de la deuda de los pasivos pensionales contingentes. Bajo el enfoque de los derechos contingentes en un nivel agregado, se analizan los puntos de incertidumbre mencionados, estimando el riesgo de crédito del gobierno central en este caso (probabilidad de default), evaluando los costos potenciales de las transferencias y calculando el spread sobre la deuda pública. Posteriormente se examina la estructura y operación del sistema pensional colombiano en la actualidad, evaluando múltiples factores de riesgo que afectan el escenario del sistema colombiano de pensiones tanto en el presente como en el futuro. Finalmente, con base en una gama de alternativas técnicas de valoración del riesgo y su implementación para el escenario de la seguridad social se ilustra la problemática del riesgo que encierra la deuda pensional en Colombia proyectando variables clave como: el salario, las cotizaciones, el empleo y el PIB. Con base en dichas proyecciones, se analiza el costo fiscal y la viabilidad de la garantía de pensión mínima.This study clarifies, the concepts of certain national debt with respect to the contingent debt as well as it identifies his impact in the sustainability of the public finances of the country. The reasoning that become about the sustainability of the debt, that is to say, if the debt of a country can be granted without a great future correction in the balance of income and expenses, go to determine in what moment a country is appropriate to refinance and when a reconstruction of the debt can be necessary. In the following pan, an analysis is made on the uncertainty around the projections of the debt and the service of the debt, which is related to the contingent rights, such as the defined ones with the explicit or implicit guarantees of the debt or the contingent pensionales liabilities. Under the approach of the contingent rights in a added level, the mentioned points of uncertainty are analyzed. We consider the risk of credit of the central government in this case (probability of default), evaluating the potential costs of the transferences and calculating spread on the national debt. Later it is examined the structure and operation del Colombian pensional system at the present time, evaluating multiple factors of risk that affect the scene as much of the Colombian system of pensions today as in the future. Finally, with base in a range of technical alternatives of valuation of the risk and its implementation for the scene of the social security the problematic one of the risk acquires knowledge that looks up the pensional debt in variable Colombia projecting key like: the wage, the quotations, the employment and the GDF. With base in these projections, one analyzes the fiscal cost and the viability of the guarantee of minimum pension

    Association between Ancestry-Specific 6q25 Variants and Breast Cancer Subtypes in Peruvian Women

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    Background: Breast cancer incidence in the United States is lower in Hispanic/Latina (H/L) compared with African American/ Black or Non-Hispanic White women. An Indigenous American breast cancer-protective germline variant (rs140068132) has been reported near the estrogen receptor 1 gene. This study tests the association of rs140068132 and other polymorphisms in the 6q25 region with subtype-specific breast cancer risk in H/Ls of high Indigenous American ancestry. Methods: Genotypes were obtained for 5,094 Peruvian women with (1,755) and without (3,337) breast cancer. Associations between genotype and overall and subtype-specific risk for the protective variant were tested using logistic regression models and conditional analyses, including other risk-associated polymorphisms in the region. Results: We replicated the reported association between rs140068132 and breast cancer risk overall [odds ratio (OR), 0.53; 95% confidence interval (CI), 0.47-0.59], as well as the lower odds of developing hormone receptor negative (HR-) versus HR+ disease (OR, 0.77; 95% CI, 0.61-0.97). Models, including HER2, showed further heterogeneity with reduced odds for HR+HER2+ (OR, 0.68; 95% CI, 0.51-0.92), HR-HER2+ (OR, 0.63; 95% CI, 0.44-0.90) and HR-HER2- (OR, 0.77; 95% CI, 0.56-1.05) compared with HR+HER2-. Inclusion of other risk-associated variants did not change these observations. Conclusions: The rs140068132 polymorphism is associated with decreased risk of breast cancer in Peruvians and is more protective against HR- and HER2+ diseases independently of other breast cancer-associated variants in the 6q25 region. Impact: These results could inform functional analyses to understand the mechanism by which rs140068132-G reduces risk of breast cancer development in a subtype-specific manner. They also illustrate the importance of including diverse individuals in genetic studies.National Institutes of HealthRevisión por pare

    Subpopulation treatment effect pattern plot analysis: a prognostic model for distant recurrence-free survival to estimate delayed adjuvant chemotherapy initiation effect in triple-negative breast cancer

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    IntroductionTriple-negative breast cancer (TNBC) is a heterogeneous disease associated with a poor prognosis. Delaying in time to start adjuvant chemotherapy (TTC) has been related to an increased risk of distant recurrence-free survival (DRFS). We aimed to develop a prognostic model to estimate the effects of delayed TTC among TNBC risk subgroups.Materials and methodsWe analyzed 687 TNBC patients who received adjuvant chemotherapy at the Instituto Nacional de Enfermedades Neoplasicas (Lima, Peru). Database was randomly divided to create a discovery set (n=344) and a validation set (n=343). Univariate and multivariate Cox regression models were performed to identify prognostic factors for DRFS. Risk stratification was implemented through two models developed based on proportional hazard ratios from significant clinicopathological characteristics. Subpopulation treatment effect pattern plot (STEPP) analysis was performed to determine the best prognostic cut-off points for stratifying TNBC subgroups according to risk scores and estimate Kaplan-Meier differences in 10-year DRFS comparing TTC (≤30 vs.>30 days).ResultsIn univariate analysis, patients aged ≥70 years (HR=4.65; 95% CI: 2.32-9.34; p=<0.001), those at stages pT3-T4 (HR=3.28; 95% CI: 1.57-6.83; p=0.002), and pN2-N3 (HR=3.00; 95% CI: 1.90-4.76; p=<0.001) were notably associated with higher risk. STEPP analysis defined three risk subgroups for each model. Model N°01 categorized patients into low (score: 0–31), intermediate (score:32–64), and high-risk (score: 65–100) cohorts; meanwhile, Model N°02: low (score: 0–26), intermediate (score: 27–55), and high (score: 56–100). Kaplan-Meier plots showed that in the discovery set, patients with TTC>30 days experienced a 17.5% decrease in 10-year DRFS rate (95%CI=6.7-28.3), and the impact was more remarkable in patients who belong to the high-risk subgroup (53.3% decrease in 10 years-DRFS rate). Similar results were found in the validation set.ConclusionsWe developed two prognostic models based on age, pT, and pN to select the best one to classify TNBC. For Model N°02, delayed adjuvant chemotherapy conferred a higher risk of relapse in patients ≥70 years and who were characterized by pT3/T4 and pN2/N3. Thus, more efforts should be considered to avoid delayed TTC in TNBC patients, especially those in high-risk subgroups

    Temporal controls on silicic acid utilisation along the West Antarctic Peninsula

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    The impact of climatic change along the Antarctica Peninsula has been widely debated in light of atmospheric/oceanic warming and increases in glacial melt over the past half century. Particular concern exists over the impact of these changes on marine ecosystems, not only on primary producers but also on higher trophic levels. Here we present a record detailing the historical controls on the biogeochemical cycling of silicic acid [Si(OH)4] on the west Antarctica Peninsula margin, a region in which the modern phytoplankton environment is constrained by seasonal sea-ice. We demonstrate that Si(OH)4 cycling through the Holocene alternates between being primarily regulated by sea-ice or glacial discharge from the surrounding grounded ice-sheet. With further climate-driven change and melting forecast for the 21st Century, our findings document the potential for biogeochemical cycling and multi-trophic interactions along the peninsula to be increasingly regulated by glacial discharge, altering food-web interactions

    Bone Mass and the CAG and GGN Androgen Receptor Polymorphisms in Young Men

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    BACKGROUND: To determine whether androgen receptor (AR) CAG (polyglutamine) and GGN (polyglycine) polymorphisms influence bone mineral density (BMD), osteocalcin and free serum testosterone concentration in young men. METHODOLOGY/PRINCIPAL FINDINGS: Whole body, lumbar spine and femoral bone mineral content (BMC) and BMD, Dual X-ray Absorptiometry (DXA), AR repeat polymorphisms (PCR), osteocalcin and free testosterone (ELISA) were determined in 282 healthy men (28.6+/-7.6 years). Individuals were grouped as CAG short (CAG(S)) if harboring repeat lengths of < or = 21 or CAG long (CAG(L)) if CAG > 21, and GGN was considered short (GGN(S)) or long (GGN(L)) if GGN < or = 23 or > 23. There was an inverse association between logarithm of CAG and GGN length and Ward's Triangle BMC (r = -0.15 and -0.15, P<0.05, age and height adjusted). No associations between CAG or GGN repeat length and regional BMC or BMD were observed after adjusting for age. Whole body and regional BMC and BMD values were similar in men harboring CAG(S), CAG(L), GGN(S) or GGN(L) AR repeat polymorphisms. Men harboring the combination CAG(L)+GGN(L) had 6.3 and 4.4% higher lumbar spine BMC and BMD than men with the haplotype CAG(S)+GGN(S) (both P<0.05). Femoral neck BMD was 4.8% higher in the CAG(S)+GGN(S) compared with the CAG(L)+GGN(S) men (P<0.05). CAG(S), CAG(L), GGN(S), GGN(L) men had similar osteocalcin concentration as well as the four CAG-GGN haplotypes studied. CONCLUSION: AR polymorphisms have an influence on BMC and BMD in healthy adult humans, which cannot be explained through effects in osteoblastic activity
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