The cost of doing nothing: Testing the benefits of water disposal risk reduction with water management Activism investing in Latin America

El costo de hacer nada: Una prueba de los beneficios de la reducción del riesgo de disposición de agua por medio de inversión activista en aguaObjetivo: Se responde la pregunta ¿cuál sería el desempeño de un inversionista si invierte solo en compañías con un adecuado manejo de agua en Latino Amética? Metodología: Se emplea la razón de consumo de agua entre ingresos (WTR) para medir la calidad de las políticas de manejo de agua en la empresa. También simula el desempeño de un inversionista invertido principalemente en empresas con el mejor WTR (del 6 de enero del 2005 al 20 de abril del 2022). Resultados: Al comparar el portafolio simulado contra el de mercado, los resultados sugieren que ambos tienen un desempeño similar en el corto plazo. En el largo plazo, las pruebas evidencian que el portafolio WTR tiene un riesgo sistemático menor (beta de 0.26), y su desempeño es más estable (media-varianza eficiente). Los resultados controlan el impacto de fluctuaciones cambiarias en algunos paises latinoamericanos. Conclusiones: Los resultados pueden ser de utilidad para inversionistas activistas de consumo de agua, motivar mejores prácticas de manejo de agua en las empresas y reducir el riesgo de disposición de agua en años venideros.Objective: This paper answers What would the performance of an investor be if she or he invested only in public companies with proper water management practices in Latin America (LATAM)? Methodology: The research uses the water-to-revenues (WTR) ratio to measure water management quality. It simulates the performance of an investor invested mainly in companies with the best WTR (from January 6th, 2005, to Abril 20, 2022). Results: Comparing the simulated portfolio’s performance against a broad market portfolio, the results suggest that both portfolios have similar performance in the short term. In the long term, the tests found that the WTR has a low systematic (market) risk (beta of 0.26), and its performance is more stable (mean-variance efficient) than the market portfolio. The tests also control the impact of some LATAM currencies’ depreciation. Conclusions: The results could be useful for investors to engage in water management activism through investing, motivate companies to engage in better water management practices, and reduce the future risk that water disposal represents to the world in years to come

Quantum diffusion on a cyclic one dimensional lattice

The quantum diffusion of a particle in an initially localized state on a cyclic lattice with N sites is studied. Diffusion and reconstruction time are calculated. Strong differences are found for even or odd number of sites and the limit N->infinit is studied. The predictions of the model could be tested with micro - and nanotechnology devices.Comment: 17 pages, 5 figure

EPR before EPR: a 1930 Einstein-Bohr thought experiment revisited

In 1930 Einstein argued against consistency of the time-energy uncertainty relation by discussing a thought experiment involving a measurement of mass of the box which emitted a photon. Bohr seemingly triumphed over Einstein by arguing that the Einstein's own general theory of relativity saves the consistency of quantum mechanics. We revisit this thought experiment from a modern point of view at a level suitable for undergraduate readership and find that neither Einstein nor Bohr was right. Instead, this thought experiment should be thought of as an early example of a system demonstrating nonlocal "EPR" quantum correlations, five years before the famous Einstein-Podolsky-Rosen paper.Comment: 11 pages, revised, accepted for publication in Eur. J. Phy

The benefits of active portfolio management. A reform proposal to Michoacan State’s Public Pension Fund Office

El presente artículo estudia el contexto legal y administrativo de uno de los fondos de pensiones de beneficio definido políticamente más relevantes en México, la Dirección de Pensiones Civiles del Estado de Michoacán. Como consecuencia de esto, se hace la propuesta de una política, estructura y proceso de gestión activa de carteras para su reserva técnica. Para probar la pertinencia de la propuesta, se realizó una simulación de eventos discretos con tres tipos de matrices de covarianzas, empleando el modelo Markowitz- Tobin-Sharpe-Lintner. Los resultados demuestran que se superan los objetivos actuariales planteados y se logra incrementar, como consecuencia, el periodo de suficiencia financiera del plan de pensiones

Cataract in professionals exposed to solar radiation: a cross sectional study

Purpose: To find out frequency of cataract in seaside workers and possible factors associated to its development. Study Design: Cross sectional observational. Place and Duration of Study: Tyrrhenian coast of Tuscany (Italy), between Rosignano Marittimo and Cecina municipalities in July 2021. Methods: Ninety-eight seaside workers were selected through convenience sampling technique. All the working subjects selected for this study had a bilateral natural vision equal to or greater than 6/10 in the anamnestic data collection, declared they had not eye diseases in the past and rarely used protective glasses during their work. Results: The mean age of 98 outdoor workers is 40. Patients with the cataract are older than people without cataract (median 41 vs 38) (p < 0.001) and have a lower visual acuity (0.6 vs 0.7) (p < 0.001); stratifying by job, refraction state and Intra Ocular Pressure (IOP), there aren’t significant association with cataract. The multivariate analysis confirms that age and visual acuity are associated with the development of the cataract (OR 1.99 and 0.01, respectively). Conclusion: Although senile cataract is an age related disease but Visually significant cataract is seen in persons working outdoors for longer hours

Promoting post-stroke recovery through focal or whole body vibration: criticisms and prospects from a narrative review

Objective: Several focal muscle vibration (fMV) and whole body vibration (WBV) protocols have been designed to promote brain reorganization processes in patients with stroke. However, whether fMV and WBV should be considered helpful tools to promote post-stroke recovery remains still largely unclear. Methods: We here achieve a comprehensive review of the application of fMV and WBV to promote brain reorganization processes in patients with stroke. By first discussing the putative physiological basis of fMV and WBV and then examining previous observations achieved in recent randomized controlled trials (RCT) in patients with stroke, we critically discuss possible strength and limitations of the currently available data. Results: We provide the first systematic assessment of fMV studies demonstrating some improvement in upper and lower limb functions, in patients with chronic stroke. We also confirm and expand previous considerations about the rather limited rationale for the application of current WBV protocols in patients with chronic stroke. Conclusion: Based on available information, we propose new recommendations for optimal stimulation parameters and strategies for recruitment of specific stroke populations that would more likely benefit from future fMV or WBV application, in terms of speed and amount of post-stroke functional recovery

Enhancing portfolio performance and VIX futures trading timing with markov-switching GARCH models

In the present paper, we test the use of Markov-Switching (MS) models with time-fixed or Generalized Autoregressive Conditional Heteroskedasticity (GARCH) variances. This, to enhance the performance of a U.S. dollar-based portfolio that invest in the S&P 500 (SP500) stock index, the 3-month U.S. Treasury-bill (T-BILL) or the 1-month volatility index (VIX) futures. For the investment algorithm, we propose the use of two and three-regime, Gaussian and t-Student, MS and MS-GARCH models. This is done to forecast the probability of high volatility episodes in the SP500 and to determine the investment level in each asset. To test the algorithm, we simulated 8 portfolios that invested in these three assets, in a weekly basis from 23 December 2005 to 14 August 2020. Our results suggest that the use of MS and MS-GARCH models and VIX futures leads the simulated portfolio to outperform a buy and hold strategy in the SP500. Also, we found that this result holds only in high and extreme volatility periods. As a recommendation for practitioners, we found that our investment algorithm must be used only by institutional investors, given the impact of stock trading fees.This research was funded by the Coordinación de la Investigación Científica at Universidad Michoacana de San Nicolás de Hidalgo and by the Instituto Politécnico Naciona

The synergistic effect between positivity, socio-demographic factors and smoking cessation: results of a cohort study

OBJECTIVE: To examine the extent to which a effect does exist between Positivity (POS), smoking and socio-demographic factors in determining quitting smoking in subjects participating in a Group Counselling Program (GCP) for smoking cessation.METHODS: 481 subjects were contacted through a telephone call. A logistic regression analysis was carried out. Possible interaction between sociodemographic variables and POS level was tested using the Synergism Index (SI).RESULTS: For individuals with a POS level over or equal to 3.4 the odds of being smoker was significantly higher among females (OR = 1.55), who smoked at home (OR = 2.16) and lower if there had children at home (OR = 0.53). For individuals with a POS level under 3.4, the only significant variable associated with smoking was beinga female (OR = 2.58). As far concerns the synergistic effect between the variables considered does exist between POS levels and having children at home (SI=1.13) and female gender (SI = 2.8).CONCLUSIONS: The synergistic effect between POS and sociodemographic factors adds evidence on the use of POS as possible determinants of individual happiness

Functional assessment of cancer therapy questionnaire for breast cancer (FACT-B+4): Italian version validation

BACKGROUND: Improvements in breast cancer diagnosis and treatment led to an increased incidence of survivors' rate. The healthcare system has to face new problems related not only to the treatment of the disease, but also to the management of the quality of life after the diagnosis. The aim of this study was to validate the Italian version of the Functional Assessment of Cancer Therapy - Breast (FACT-B+4) questionnaire and to evaluate its reliability. METHODS: The questionnaire was administered twice, with an interval of three days between each administration, to a cohort of women of the Breast Surgical Unit, PoliclincoUmberto I. Cronbach's alpha was used as a measure of the internal consistency of the Italian version. RESULTS: The Italian version of the tool was administered to 55 subjects. The Cronbach's alpha for most scores registered values >0.7, both at baseline and at the follow-up analysis, therefore the subscale showed good internal consistency. CONCLUSIONS: The Italian version of FACT-B+4 demonstrated acceptable reliability properties in the Breast Unit patients. The use of this questionnaire seemed to be effective and in line with the results derived from the English and Spanishversions. Internal consistency and validity had similar performance results

mm-Wave DRW Antenna Phase Centre Determination

This document presents an approach to the phase centre determination of a dielectric rod waveguide (DRW) antenna by means of measurements obtained with a planar measuring system at millimeter wave lengths. Phase centre determination by the least squares fit technique is described in this document for different DRW antennas (silicon and sapphire). Results at different operating frequencies are offered