110 research outputs found

    Visions of Global Electronic Mastery

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    Este texto es una de las últimas aportaciones del pionero de la Economía Política de la Comunicación Herbert I. Schiller. El él mantiene una de sus líneas de investigación fundamentales: la extensión de la doctrina del libre flujo de la información como parte de la política exterior estadounidense. Sólo que en este caso se aplica al comercio electrónico y la era digital. En este sentido uno de lo documentos analizados en profundidad por el autor, The Framework for Global Electronic Comerce, representa la actualización de la doctrina. De esta manera el mantenimiento de la hegemonía de Estados Unidos y su supremacía electrónica global serán posibles a lo largo del siglo XXI.This text is one of the last contributions of pioneer of Political Economy of Communication Herbert I. Schiller. The author keeps up with one of his fundamental thesis, that is, the extension of the free flow of information doctrine as part of the US foreign policy. In this case it is applied to electronic commerce and the digital era. In this sense one of the documents analysed in depth by the author, The Framework for Electronic Commerce, represents the actualization of this doctrine. Thus the preservation of US hegemony and its global electronic mastery will be a fact along the 21st century

    Augurios de supremacía electrónica global

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    Este texto es una de las últimas aportaciones del pionero de la Economía Política de la Comunicación Herbert I. Schiller. El él mantiene una de sus líneas de investigación fundamentales: la extensión de la doctrina del libre flujo de la información como parte de la política exterior estadounidense. Sólo que en este caso se aplica al comercio electrónico y la era digital. En este sentido uno de lo documentos analizados en profundidad por el autor, The Framework for Global Electronic Comerce, representa la actualización de la doctrina. De esta manera el mantenimiento de la hegemonía de Estados Unidos y su supremacía electrónica global serán posibles a lo largo del siglo XXI

    Highly resolved observations of trace gases in the lowermost stratosphere and upper troposphere from the Spurt project: an overview

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    During SPURT (Spurenstofftransport in der Tropopausenregion, trace gas transport in the tropopause region) we performed measurements of a wide range of trace gases with different lifetimes and sink/source characteristics in the northern hemispheric upper troposphere (UT) and lowermost stratosphere (LMS). A large number of in-situ instruments were deployed on board a Learjet 35A, flying at altitudes up to 13.7 km, at times reaching to nearly 380 K potential temperature. Eight measurement campaigns (consisting of a total of 36 flights), distributed over all seasons and typically covering latitudes between 35° N and 75° N in the European longitude sector (10° W–20° E), were performed. Here we present an overview of the project, describing the instrumentation, the encountered meteorological situations during the campaigns and the data set available from SPURT. Measurements were obtained for N2O, CH4, CO, CO2, CFC12, H2, SF6, NO, NOy, O3 and H2O. We illustrate the strength of this new data set by showing mean distributions of the mixing ratios of selected trace gases, using a potential temperature – equivalent latitude coordinate system. The observations reveal that the LMS is most stratospheric in character during spring, with the highest mixing ratios of O3 and NOy and the lowest mixing ratios of N2O and SF6. The lowest mixing ratios of NOy and O3 are observed during autumn, together with the highest mixing ratios of N2O and SF6 indicating a strong tropospheric influence. For H2O, however, the maximum concentrations in the LMS are found during summer, suggesting unique (temperature- and convection-controlled) conditions for this molecule during transport across the tropopause. The SPURT data set is presently the most accurate and complete data set for many trace species in the LMS, and its main value is the simultaneous measurement of a suite of trace gases having different lifetimes and physical-chemical histories. It is thus very well suited for studies of atmospheric transport, for model validation, and for investigations of seasonal changes in the UT/LMS, as demonstrated in accompanying and elsewhere published studies

    On the Possibility of Measuring the Gravitomagnetic Clock Effect in an Earth Space-Based Experiment

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    In this paper the effect of the post-Newtonian gravitomagnetic force on the mean longitudes ll of a pair of counter-rotating Earth artificial satellites following almost identical circular equatorial orbits is investigated. The possibility of measuring it is examined. The observable is the difference of the times required to ll in passing from 0 to 2π\pi for both senses of motion. Such gravitomagnetic time shift, which is independent of the orbital parameters of the satellites, amounts to 5×107\times 10^{-7} s for Earth; it is cumulative and should be measured after a sufficiently high number of revolutions. The major limiting factors are the unavoidable imperfect cancellation of the Keplerian periods, which yields a constraint of 102^{-2} cm in knowing the difference between the semimajor axes aa of the satellites, and the difference II of the inclinations ii of the orbital planes which, for i0.01i\sim 0.01^\circ, should be less than 0.0060.006^\circ. A pair of spacecrafts endowed with a sophisticated intersatellite tracking apparatus and drag-free control down to 109^{-9} cm s2^{-2} Hz1/2^{-{1/2}} level might allow to meet the stringent requirements posed by such a mission.Comment: LaTex2e, 22 pages, no tables, 1 figure, 38 references. Final version accepted for publication in Classical and Quantum Gravit

    Nonlinear adiabatic response of interacting quantum dots

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    We develop a generic method in Liouville space to describe the dissipative dynamics of coherent interacting quantum dots with adiabatic time dependence beyond linear response. We show how the adiabatic response can be related to effective quantities known from real-time renormalization group methods for stationary quantities. We propose the study of a generalized RCRC-time as a characteristic time scale. We apply the method to the interacting resonant level model and calculate the nonlinear adiabatic charge response to time-dependent gate voltages, tunneling barriers and Coulomb interaction. The generalized RCRC-time is found to acquire a unique form in all cases, in contrast to the capacitance and the charge relaxation resistance. We discuss the observability of the effects in molecular systems and cold atom setups.Comment: 6 page

    An integrated cell atlas of the lung in health and disease

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    Single-cell technologies have transformed our understanding of human tissues. Yet, studies typically capture only a limited number of donors and disagree on cell type definitions. Integrating many single-cell datasets can address these limitations of individual studies and capture the variability present in the population. Here we present the integrated Human Lung Cell Atlas (HLCA), combining 49 datasets of the human respiratory system into a single atlas spanning over 2.4 million cells from 486 individuals. The HLCA presents a consensus cell type re-annotation with matching marker genes, including annotations of rare and previously undescribed cell types. Leveraging the number and diversity of individuals in the HLCA, we identify gene modules that are associated with demographic covariates such as age, sex and body mass index, as well as gene modules changing expression along the proximal-to-distal axis of the bronchial tree. Mapping new data to the HLCA enables rapid data annotation and interpretation. Using the HLCA as a reference for the study of disease, we identify shared cell states across multiple lung diseases, including SPP1+ profibrotic monocyte-derived macrophages in COVID-19, pulmonary fibrosis and lung carcinoma. Overall, the HLCA serves as an example for the development and use of large-scale, cross-dataset organ atlases within the Human Cell Atlas

    The Human Affectome

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    Over the last decades, the interdisciplinary field of the affective sciences has seen proliferation rather than integration of theoretical perspectives. This is due to differences in metaphysical and mechanistic assumptions about human affective phenomena (what they are and how they work) which, shaped by academic motivations and values, have determined the affective constructs and operationalizations. An assumption on the purpose of affective phenomena can be used as a teleological principle to guide the construction of a common set of metaphysical and mechanistic assumptions—a framework for human affective research. In this capstone paper for the special issue “Towards an Integrated Understanding of the Human Affectome”, we gather the tiered purpose of human affective phenomena to synthesize assumptions that account for human affective phenomena collectively. This teleologically-grounded framework offers a principled agenda and launchpad for both organizing existing perspectives and generating new ones. Ultimately, we hope Human Affectome brings us a step closer to not only an integrated understanding of human affective phenomena, but an integrated field for affective research

    Acute mountain sickness.

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    Acute mountain sickness (AMS) is a clinical syndrome occurring in otherwise healthy normal individuals who ascend rapidly to high altitude. Symptoms develop over a period ofa few hours or days. The usual symptoms include headache, anorexia, nausea, vomiting, lethargy, unsteadiness of gait, undue dyspnoea on moderate exertion and interrupted sleep. AMS is unrelated to physical fitness, sex or age except that young children over two years of age are unduly susceptible. One of the striking features ofAMS is the wide variation in individual susceptibility which is to some extent consistent. Some subjects never experience symptoms at any altitude while others have repeated attacks on ascending to quite modest altitudes. Rapid ascent to altitudes of 2500 to 3000m will produce symptoms in some subjects while after ascent over 23 days to 5000m most subjects will be affected, some to a marked degree. In general, the more rapid the ascent, the higher the altitude reached and the greater the physical exertion involved, the more severe AMS will be. Ifthe subjects stay at the altitude reached there is a tendency for acclimatization to occur and symptoms to remit over 1-7 days
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