Capital de trabajo, gestión de tesorería y valuación de empresas

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

On the discontinuity of the quantum Fisher information for quantum statistical models with parameter dependent rank

We address the discontinuities of the quantum Fisher information (QFI) that may arise when the parameter of interest takes values that change the rank of the quantum statistical model. We revisit the classical and the quantum Cram\ue9r-Rao theorems, show that they do not hold in these limiting cases, and discuss how this impacts on the relationship between the QFI and the Bures metric. In order to illustrate the metrological implications of our findings, we present two paradigmatic examples, where we discuss in detail the role of the discontinuities. We show that the usual equivalence between the variance of the maximum likelihood estimator and the inverse of the QFI breaks down

Climate variability along latitudinal and longitudinal transects in East Antarctica

AbstractIn the framework of the International Trans-Antarctic Scientific Expedition (ITASE) programme, France and Italy carried out a traverse along one west–east and two north–south transects in East Antarctica from November 2001 to January 2002. Eighteen shallow snow–firn cores were drilled, and surface snow samples were collected every 5km along the traverse. Firn temperatures were measured in boreholes down to 30 m. The cores were analyzed for β radioactivity to obtain snow accumulation-rate data. The surface snow samples were analyzed for δ18O to correlate isotopic values with borehole temperatures. Multiple regression analysis shows a global near-dry-adiabatic lapse rate and a latitudinal lapse rate of 1.05˚C(˚ lat. S)–1, in the Dome C drainage area. Analysis of firn temperatures reveals a super-adiabatic lapse rate along the ice divide between Talos Dome and the Southern Ocean coast, and in some sectors along the ice divide between the Astrolabe Basin and D59. Snow accumulation rates and firn temperatures show warmer temperatures and higher accumulation values close to the ice divides extending from Talos Dome and Dome C to the Southern Ocean. The spatial pattern of data is linked with a katabatic-wind-source basin and moisture-source region

Clinical evaluation of the FloTrac/VigileoTM system and two established continuous cardiac output monitoring devices in patients undergoing cardiac surgery†‡

Background Assessment of cardiac output (CO) by the FloTrac/Vigileo™ system may offer a less invasive means of determining the CO than either the pulmonary artery catheter (PAC) or the PiCCOplus™ system. The aim of this study was to compare CO measurements made using the FloTrac/Vigileo™ system with upgraded software (FCO, Edwards Lifesciences, Irvine CA, USA), the PiCCOplus™ system (PCO, Pulsion Medical Systems, Munich, Germany) and continuous CO monitoring using a PAC (CCO; Vigilance™ monitoring, Edwards Lifesciences, Irvine CA, USA) with intermittent pulmonary artery thermodilution (ICO). The study was conducted in patients undergoing elective cardiac surgery. Methods Thirty-one patients with preserved left ventricular function were enrolled. CCO, FCO, and PCO were recorded in the perioperative period at six predefined time points after achieving stable haemodynamic conditions; ICO was determined from the mean of three bolus injections. Bland-Altman analysis was used to compare CCO, FCO, and PCO with ICO. Results Bland-Altman analysis revealed a comparable mean bias and limits of agreement for all tested continuous CO monitoring devices using ICO as reference method. Agreement for all devices decreased in the postoperative period. Conclusion The performance of the FloTrac/Vigileo™ system, the PiCCOplus™, and the Vigilance™ CCO monitoring for CO measurement were comparable when tested against intermittent thermodilution in patients undergoing elective cardiac surger

Volumetric preload measurement by thermodilution: a comparison with transoesophageal echocardiography

Background. End-diastolic volume indices determined by transpulmonary thermodilution and pulmonary artery thermodilution may give a better estimate of left ventricular preload than pulmonary capillary wedge pressure monitoring. The aim of this study was to compare volume preload monitoring using the two different thermodilution techniques with left ventricular preload assessment by transoesophageal echocardiography (TOE). Methods. Twenty patients undergoing elective cardiac surgery with preserved left-right ventricular function were studied after induction of anaesthesia. Conventional haemodynamic variables, global end-diastolic volume index using the pulse contour cardiac output (PiCCO) system (GEDVIPiCCO), continuous end-diastolic volume index (CEDVIPAC) measured by a modified pulmonary artery catheter (PAC), left ventricular end-diastolic area index (LVEDAI) using TOE and stroke volume indices (SVI) were recorded before and 20 and 40 min after fluid replacement therapy. Analysis of variance (Bonferroni-Dunn), Bland-Altman analysis and linear regression were performed. Results. GEDVIPiCCO, CEDVIPAC, LVEDAI and SVIPiCCO/PAC increased significantly after fluid load (P10% for GEDVIPiCCO and LVEDAI was observed in 85% and 90% of the patients compared with 45% for CEDVIPAC. Mean bias (2 sd) between percentage changes (Δ) in GEDVIPiCCO and ΔLVEDAI was −3.2 (17.6)% and between ΔCEDVIPAC and ΔLVEDAI −8.7 (30.0)%. The correlation coefficient (r2) for ΔGEDVIPiCCO vs ΔLVEDAI was 0.658 and for ΔCEDVIPAC vs ΔLVEDAI 0.161. The relationship between ΔGEDVIPiCCO and ΔSVIPiCCO was stronger (r2=0.576) than that between ΔCEDVIPAC and ΔSVIPAC (r2=0.267). Conclusion. GEDVI assessed by the PiCCO system gives a better reflection of echocardiographic changes in left ventricular preload, in response to fluid replacement therapy, than CEDVI measured by a modified PA

Optimal estimation of joint parameters in phase space

We address the joint estimation of the two defining parameters of a displacement operation in phase space. In a measurement scheme based on a Gaussian probe field and two homodyne detectors, it is shown that both conjugated parameters can be measured below the standard quantum limit when the probe field is entangled. We derive the most informative Cram\'er-Rao bound, providing the theoretical benchmark on the estimation and observe that our scheme is nearly optimal for a wide parameter range characterizing the probe field. We discuss the role of the entanglement as well as the relation between our measurement strategy and the generalized uncertainty relations.Comment: 8 pages, 3 figures; v2: references added and sections added to the supplemental material; v3: minor changes (published version