781 research outputs found
Crecimiento económico y emisiones de CO2 por combustión de energéticos en México, 2005-2030
Within the simulation horizon, through several scenerios related to the performance of the Mexican and international economies, CO2 emissions derived from energetic combustion are determined; and these could be classified as a base line for the design and implementation of policies that could reduce them. Furthermore, these emissions are projected through an extrapolation process, and the results of “official” policies to diminish them are determined given the existing assortment of goals; hence, the gaps pending for elimination are identified. On the other hand, the variety of policies implemented nowadays are not enough to face the problem’s magnitude; thus requiring the impulse of nuclear technology for power generation, the adoption of bio-fuels which allow an articulation with the agricultural sector, intense utilization of available energetics, more renewables, and the efficient usage of energy amongst many other policies.Mexican economic growth, 2030 projections, CO2 emissions
Fuel additive
A fuel additive comprising one or more complex oxides having a nominal compn. as set out in formula (1): AxB1-yMyOn; wherein A is selected from one or more group III elements including the lanthanide elements or one or more divalent or monovalent cations; B is selected from one or more elements with at. no. 22 to 24, 40 to 42 and 72 to 75; M is selected from one or more elements with at. no. 25 to 30; x is defined as a no. where 0 < x ≤ l; y is defined as a no. where 0 ≤ y < 0.5. [on SciFinder(R)
Crecimiento y concentración de los principales grupos empresariales en México
Incluye BibliografíaEn este trabajo se discuten diversas hipótesis sobre el origen yoperación de los grupos económicos y se plantea un modelo destinadoa explicar las fuentes de crecimiento de los activos totales. Se muestrala creciente contribución de los grupos económicos mexicanos al pib,mientras que sus aportaciones en términos del empleo y las utilidadesson menores. Se observa a lo largo del tiempo un claro fenómenode concentración de las ventas y activos en favor de los grupos másimportantes. Se concluye que la principal fuente de financiamiento dela expansión de los activos entre 2005 y 2007 fueron el crecimientode los pasivos y, en segundo lugar, las aportaciones patrimonialesde los accionistas. Se determina que la inversión de los principalesgrupos se realiza de manera discreta en el tiempo y que estos tiendena "sobreinvertir" como una forma de obstruir la entrada de otroscompetidores
Phonon Dispersions as Indicators of Dynamic Symmetry Reduction in Superconductors
Strong correlations between phonon energies and superconducting transition temperatures can be extracted from phonon dispersion calculations using density functional theory for a range of superconducting materials. These correlations are robust and consistent with experimental data for key external conditions including isotope effects, elemental substitutions and pressure variations. Changes in the electronic band structure also correlate with transitions to/from superconductivity but, in general, are less sensitive and less obvious than phonon behaviour. A computational approach that considers both phonons and electrons and the presence or absence of a phonon anomaly works well for conventional superconducting materials with hexagonal, cubic or tetragonal symmetries. Superconductivity in these compounds often involves symmetry reduction in an original non-superconducting parent compound induced, for instance, by substitution or by a dynamic reduction in symmetry shown in electron density distributions and Raman spectra. Such symmetry reduction is effectively modelled with super-lattice constructs which link Raman spectra with key superconducting parameters
Diabetes e Insuficiencia Cardíaca
Diabetes Mellitus (DM) is a chronic non-communicable cardio-metabolic disease that causes macro-vascular complications such as atherosclerosis, coronary disease and heart failure (HF). There is a bidi- rectional relationship between HF and DM, HF being the second most frequent initial cardiovascular event in patients with diabetes. It may even be the first cardiovascular complication, before acute my- ocardial infarction.DM can lead to HF through mechanisms mediated by atherosclerosis and non mediated by it. In the first case, cholesterol is deposited in coronary arteries, favored by the presence of other risk factors. In the second case, the myocardium is directly affected leading to structural and functional changes through non-atherogenic mechanisms (called Diabetic Cardiomyopathy).The treatment of HF with reduced ejection fraction in the diabetic patient does not differ from that of the non-diabetic population, the triple neurohumoral block must be achieved. In the case of patients with HF with ejection fraction preserved to date, we do not have specific therapy to reduce cardiovas- cular morbidity and mortality.
In the diabetes treatment of the patient with HF, sodium-glucose type 2 cotransporter inhibitors (SGLT2i) clearly stand out. In addition to their glucosuric and natriuretic effect, they have pleiotropic effects that produce metabolic, hemodynamic and cellular viability effects preventing apoptosis and cell death. Finally, the clinical benefits of SGLT2 inhibitors in HF go beyond glycemic control, as demon- strated by the DAPA-HF study; initiating a new era in the treatment of patients with HF with reduced ejection fraction.La Diabetes Mellitus (DM) es una enfermedad crónica cardiometabólica no transmisible, que origina complicaciones macrovasculares como aterosclerosis, enfermedad coronaria e insuficiencia cardíaca (IC). Existe una relación bidireccional entre IC y DM, siendo IC el segundo evento cardiovascular inicial más frecuente en pacientes con diabetes. Incluso puede ser la primera complicación cardiovascular, antes que el infarto de miocardio.La DM puede conducir a IC a través de mecanismos mediados por aterosclerosis e independientemente de esta. En el primer caso, se produce depósito de colesterol en las arterias coronarias, favorecido por la presencia de otros factores de riesgo. En el segundo caso, a través de mecanismos no aterogénicos (denominada Cardiomiopatía Diabética), conduciendo a cambios estructurales y funcionaes.El tratamiento de la IC con fracción de eyección reducida en el paciente diabético no difiere del de la población no diabética. Se debe conseguir el triple bloqueo neurohumoral. En el caso de los pacientes con IC con fracción de eyección preservada hasta la fecha no tenemos terapia específica que disminuya la morbimortalidad cardiovascular.En el tratamiento de la diabetes del paciente con IC sobresalen claramente los inhibidores del cotransportador sodio-glucosa tipo 2 (iSGLT2) que además de su efecto glucosúrico y natriurético, presentan efectos pleiotrópicos que ejercen una acción metabólica, hemodinámica y en la viabilidad celular al prevenir apoptosis y muerte celular. Finalmente, los beneficios clínicos de los inhibidores SGLT2 en IC van más allá del control glicémico, como lo demostró el estudio DAPA-HF; iniciando una nueva era en el tratamiento del paciente con IC con fracción de eyección reducida
Modelos macroeconométricos en el Perú: nuevos aportes
Compila algunos de los modelos macroeconómicos matemáticos y econométricos recientemente diseñados para la economía peruana. Contiene ocho artículos; seis referidos a modelos estimados cuantitativamente, y los restantes presentan un planteamiento teórico de cómo trabajar la realidad
Profit margins, financing and investment in the Peruvian business sector (1998-2008)
Includes bibliographyThis paper develops a model and explains the determinants of profitmargins in the Peruvian business sector in the 1998-2008 period. Theseare established in a fixed-price scenario, with reference to a set of variablessuch as the price elasticity of demand, the behaviour of possible industryentrants and any regulatory intervention by government. In addition,there is a direct relationship between profit margins and self-financingof investment. Profit margins and profit ratios in the business sector arerising and exceed international norms. The paper also identifies a trendtowards lower levels of debt and leverage. It does not reject the hypothesisof linkage between profit margins and investment at the aggregate andsectoral level. The output-to-capital ratio or sales-to-assets ratio is directlylinked to profit margins. Most investment is self-financed
Déficit fiscal, tributación y demanda efectiva
The objective of this work is to present a vision contrary to the liberal one, in which the ineffectiveness of the public sector is the consequence of the actions of the executors of economic policies. Here it is asked how the different variables are theoretically linked to the concept of “effectiveness of public sector actions” and it will be contrasted with the historical experience of the recent years. It also pretends to show that the theoretical approach of the public deficit related to the executors of economic policy corresponds to a particular theoretical option subject to strong criticism. Finally, it wants to stand out that this is a first partial (and general) attempt to propose a general hypothesis to tackle the public problem from a Keynesian-Kaleckian approach to reality.El objetivo del presente trabajo es el de presentar una visión contraria a la liberal, en la que la inefectividad del sector público es el fruto del accionar de los ejecutores de la política económica. Aquí se pregunta cómo se ligan teóricamente diferentes variables al concepto de “efectividad del accionar del sector público” y se confrontará al respecto la experiencia histórica de los últimos años. También se pretende demostrar que el enfoque teórico en relación al déficit público empleado por los ejecutores de la política económica corresponde a una particular opción teórica sujeta a fuertes críticas. Finalmente, se quiere resaltar que este es un primer intento parcial y muy general de planteamiento de hipótesis generales para abordar la problemática pública desde una perspectiva keynesiana-kaleckiana de la realidad
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