9,033 research outputs found

    Managing by values in the next milenium: Cultural redesign for strategic organizational change

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    The system of beliefs and values, that shaped the model for management and organizations during the 20th century, is just not good enough today. In order to keep a business functioning well and competing successfully in markets that are increasingly more global, complex, professionally demanding, constantly changing and oriented towards quality and customer satisfaction a new model is needed. In this paper, we will propose that both Management by Instructions (MBI) and Management by Objectives (MBO) today give notoriously inadequate results. By contrast, description of a new approach labeled: Management by Values (MBV), seem to be emerging as a strategic leadership tool. The paper outlines this approach and discusses the implementation of MBV as a tool to redesign culture in organizations and prepare them for the next millenium.Managing by values, management in new milenium, strategic leadership

    Modeling population dynamics and economic growth as competing species: An application to CO2 global emissions

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    Since the beginning of the last century the world is experiencing an important demographic transition, which will probably impact on economic growth. Many demographers and social scientists are trying to understand the key drivers of such transition as well as its profound implications. A correct understanding will help to predict other important trends of the world primary energy demand and the carbon emission to the atmosphere, which may be leading to an important climate change. This paper proposes a set of coupled differential equations to describe the changes of population, gross domestic product, primary energy consumption and carbon emissions, modeled as competing-species as in Lokta-Volterra prey-predator relations. The predator–prey model is well known in the biological, ecological and environmental literature and has also been applied successfully in other fields. This model proposes a new and simple conceptual explanation of the interactions and feedbacks among the principal driving forces leading to the present transition. The estimated results for the temporal evolution of world population, gross domestic product, primary energy consumption and carbon emissions are calculated from year 1850 to year 2150. The calculated scenarios are in good agreement with common world data and projections for the next 100 years.Population dynamics, economic growth, primary energy consumption, carbon emission model, Lokta-Volterra Equations, Prey-predator model.

    On the multiplicity of ALMA Compact Array counterparts of far-infrared bright quasars

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    We present ALMA Atacama Compact Array (ACA) 870 micron continuum maps of 28 infrared-bright SDSS quasars with Herschel/SPIRE detections at redshifts 2-4, the largest such sample ever observed with ALMA. The ACA detections are centred on the SDSS coordinates to within 1 arcsec for about 80 per cent of the sample. Larger offsets indicate that the far-infrared (FIR) emission detected by Herschel might come from a companion source. The majority of the objects (about 70 per cent) have unique ACA counterparts within the SPIRE beam down to 3-4 arcsec resolution. Only 30 per cent of the sample shows clear evidence for multiple sources with secondary counterparts contributing to the total 870 micron flux within the SPIRE beam to at least 25 per cent. We discuss the limitations of the data based on simulated pairs of point-like sources at the resolution of the ACA and present an extensive comparison of our findings with recent works on the multiplicities of sub-millimetre galaxies. We conclude that, despite the coarse resolution of the ACA, our data support the idea that, for a large fraction of FIR-bright quasars, the sub-mm emission comes from single sources. Our results suggest that, on average, optically bright quasars with strong FIR emission are not triggered by early-stage mergers but are, instead, together with their associated star formation rates, the outcome of either late-stage mergers or secular processes.Comment: 16 pages, 10 figure

    Complement activation and protein adsorption by carbon nanotubes

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    As a first step to validate the use of carbon nanotubes as novel vaccine or drug delivery devices, their interaction with a part of the human immune system, complement, has been explored. Haemolytic assays were conducted to investigate the activation of the human serum complement system via the classical and alternative pathways. Western blot and sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) techniques were used to elucidate the mechanism of activation of complement via the classical pathway, and to analyse the interaction of complement and other plasma proteins with carbon nanotubes. We report for the first time that carbon nanotubes activate human complement via both classical and alternative pathways. We conclude that complement activation by nanotubes is consistent with reported adjuvant effects, and might also in various circumstances promote damaging effects of excessive complement activation, such as inflammation and granuloma formation. C1q binds directly to carbon nanotubes. Protein binding to carbon nanotubes is highly selective, since out of the many different proteins in plasma, very few bind to the carbon nanotubes. Fibrinogen and apolipoproteins (AI, AIV and CIII) were the proteins that bound to carbon nanotubes in greatest quantit

    Non-Markovian Stochastic Resonance: three state model of ion channel gating

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    Stochastic Resonance in single voltage-dependent ion channels is investigated within a three state non-Markovian modeling of the ion channel conformational dynamics. In contrast to a two-state description one assumes the presence of an additional closed state for the ion channel which mimics the manifold of voltage-independent closed subconformations (inactivated ``state''). The conformational transition into the open state occurs through a domain of voltage-dependent closed subconformations (closed ``state''). At distinct variance with a standard two-state or also three-state Markovian approach, the inactivated state is characterized by a broad, non-exponential probability distribution of corresponding residence times. The linear response to a periodic voltage signal is determined for arbitrary distributions of the channel's recovery times. Analytical results are obtained for the spectral amplification of the applied signal and the corresponding signal-to-noise ratio. Alternatively, these results are also derived by use of a corresponding two-state non-Markovian theory which is based on driven integral renewal equations [I. Goychuk and P. Hanggi, Phys. Rev. E 69, 021104 (2004)]. The non-Markovian features of stochastic resonance are studied for a power law distribution of the residence time-intervals in the inactivated state which exhibits a large variance. A comparison with the case of bi-exponentially distributed residence times possessing the same mean value, i.e. a simplest non-Markovian two-state description, is also presented

    Capital de trabajo, gestión de tesorería y valuación de empresas

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    In the professional practice, the concept of operational working capital is confused with the accounting definition of working capital, with consequent errors both in the treasury of companies, and in the valuation of companies. In this paper we discuss the important distinction between operational working capital (a characteristic of a business) and the accounting concept of working capital (a financial decision). Also, we challenge the popular view that suggests that firms should finance with long term debt the recurrent portion of their operative working capital, discussing both the implicit costs and risks of such a strategy. Finally, taking the accounting definition of working capital for the operational working capital can lead also to important mistakes in valuation of companies. One of such too frequent mistake is to subtract only the long term debt from the present value of free cash flows to obtain an estimate of the economic value of equity, with a consequent overestimation of its value.En la practica profesional tiende a confundirse el concepto de capital de trabajo operacional, o necesidad operativa de fondos, con la definición contable de capital de trabajo; esta confusión lleva a errores importantes tanto en las áreas de tesorerfa de las firmas como en la valuación de empresas. En este articulo discutimos la importante diferencia entre estos conceptos, y argumentamos que el primero de ellos refleja características de la operación de un negocio, mientras que el segundo representa una decisión de financiamiento. Además, cuestionamos la visión popular que sugiere que las firmas financien su necesidad operativa de fondos con capital de trabajo, discutiendo los costos y riesgos implícitos de dicha decisión. Finalmente, mostramos que la confusión de conceptos mencionada puede Uevar a errores importantes en la valuación de empresas, como la practica demasiado difundida de restar solo la deuda de largo plazo al valor presente de los flujos de caja libres para obtener el valor económico del patrimonio; ello con la eonsiguiente sobre estimación de su valor

    Economic context analysis in mental health care. Usability of health financing and cost of illness studies for international comparisons

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    This paper discusses an integrated approach to mental health studies on Financing of Illness (FoI) and health accounting, Cost of Illness (CoI) and Burden of Disease (BoD). In order to expand the mental health policies, the following are suggested: (a) an international consensus on the standard scope, methods to collect and to analyse mental health data, as well as to report comparative information; (b) mathematical models are also to be validated and tested in an integrated approach, (c) a better knowledge transfer between clinicians and knowledge engineers, and between researchers and policy makers to translate economic analysis into practice and health plannin

    Eosinophilic Esophagitis beyond Eosinophils - an Emerging Phenomenon Overlapping with Eosinophilic Esophagitis: Collegium Internationale Allergologicum (CIA) Update 2023.

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    Having long been considered the mainstay in eosinophilic esophagitis (EoE) diagnosis and pathogenesis, the role of eosinophils has been questioned and might be less important than previously thought. It is well known now that EoE is a Th2-mediated disease with many more disease features than eosinophilic infiltration. With more knowledge on EoE, less pronounced phenotypes or nuances of the disease have become apparent. In fact, EoE might be only the tip of the iceberg (and the most extreme phenotype) with several variant forms, at least three, lying on a disease spectrum. Although a common (food induced) pathogenesis has yet to be confirmed, gastroenterologists and allergologists should be aware of these new phenomena in order to further characterize these patients. In the following review, we discuss the pathogenesis of EoE, particularly those mechanisms beyond eosinophilic infiltration of the esophageal mucosa, non-eosinophilic inflammatory cell populations, the new disease entity EoE-like disease, variant forms of EoE, and the recently coined term mast cell esophagitis

    An approach to corporate volunteering in Spain

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    This study aims to analyse the role of corporate volunteerism in the framework of corporate social responsibility of enterprises. After reviewing the active components in the employee volunteering concept, we present the steps taken at the European level in this area, focusing on Spain’s situation. We start with a search and comparison of information on the topic published by the major Spanish listed companies. This first approach verifies that the data are disclosed from various sources and presented heterogeneously. Then, we identify the sector that concentrates a more significant number of employees in volunteer activities. Subsequently, we focus on this sector to explore the type of volunteer activities these companies reveal according to Spanish legislation. The study sheds light on corporate governance practices, especially the disclosure of information about this activity type

    A multiphysics approach for modeling gas exchange in microperforated films for modified atmosphere packaging of respiring products

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    The objective of this work is to quantify, model and verify how the interactions between the respiring products and the surrounding atmosphere in a package affect the gas exchange through a microperforation. The pressure drop generated in a closed system by the metabolic activity of five different products has been determined by direct and indirect measurements. In this way, the estimated compensating hydrodynamic flows that can pass through the microperforated film ranged from 0.34 to 4.75 mL h(-1). A 3D model that considers the mass transfer coupled with the momentum transfer has been proposed to predict the gas concentration profiles around the microperforations originated by the diffusive and convective flows. A novel gas exchange measurement system, able to deliver small convective airflows comparable to those obtained for the different products and conditions, was assembled for the model verification. The model correctly predicts experimental data obtained for different convective flows
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