On the inconsistency of the Malmquist-Luenberger index

Apart from the well-known weaknesses of the standard Malmquist productivity index related to infeasibility and not accounting for slacks, already addressed in the literature, we identify a new and significant drawback of the Malmquist-Luenberger index decomposition that questions its validity as an empirical tool for environmental productivity measurement associated with the production of bad outputs. In particular, we show that the usual interpretation of the technical change component in terms of production frontier shifts can be inconsistent with its numerical value, thereby resulting in an erroneous interpretation of this component that passes on to the index itself. We illustrate this issue with a simple numerical example. Finally, we propose a solution for this inconsistency issue based on incorporating a new postulate for the technology related to the production of bad output

How to properly decompose economic efficiency using technical and allocative criteria with non-homothetic DEA technologies

We discuss how to properly decompose economic efficiency when the underlying technology is non-homothetic using alternative allocative and technical efficiency criteria. We first show that only under the production of one output and assuming the particular case of constant returns to scale homotheticity, we may claim that the standard radial models correctly measure pure technical efficiency. Otherwise, when non-homotheticity is assumed, we then show that these traditional estimations would measure an undetermined mix of technical and allocative efficiency. To restore a consistent measure of technical efficiency in the non-homothetic case we introduce a new methodology that takes as reference for the economic efficiency decomposition the preservation of the allocative efficiency of firms producing in the interior of the technology. This builds upon the so-called reversed approach recently introduced by Bogetoft et al. (2006) that allows estimating allocative efficiency without presuming that technical efficiency has been already accomplished. We illustrate our methodology within the Data Envelopment Analysis framework adopting the most simple nonhomothetic BCC model and a numerical example. We show that there are significant differences in the allocative and technical efficiency scores depending on the approac

MACROECONOMTC PERFORMANCE OF SIXTEEN IBERO-AMERICAN COUNTRIES OVER THE PERIOD 1980-1991

The objective of this study is to analyze the macroeconomic performance of 16 Ibero- American countries over the period 1980- 199 1. Macroeconomic performance is defined as the ability of a country's macroeconomic managers to provide four welfare-enhancing economic services to their citizens: a high leve1 of GDP per capita, a low rate of inflation, a low rate of unemployment, and a favorable trade balance. We use linear programming techniques to construct a best practice macroeconomic performance frontier, against which to measure the relative performance of each country in each year relative to al1 countries in al1 years. We then normalize the data in order to evaluate the quality of the macroeconomic management of each country. El objetivo de este estudio es analizar el rendimiento macroeconómico en 16 países Iberoamericanos durante el período 1980-1991. Se define dicho rendimiento como la capacidad de sus gobernantes de proporcionar cuatro servicios económicos que aumenten el bienestar de sus habitantes: un alto nivel de GDP per cápita, una bajo coeficiente de inflación, un bajo coeficiente en la tasa de desempleo y una balanza comercial favorable. Se usan técnicas de programación lineal para construir la "mejor" frontera experimental de rendimiento macroeconómico, y ésta se usa para evaluar el rendimiento relativo de cada país en cada uno de los años estudiados respecto al conjunto formado por todos los paises durante todos los años. A continuación se normalizan los datos con el fin de evaluar la calidad de la administración macroeconómica de cada país.DEA, Eficiencia, Rendimiento Macroeconómico. DEA, Efficiency , Macroeconomic Performance.

A computational analysis of the impact of bore-to-stroke ratio on emissions and efficiency of a HSDI engine

[EN] Research on combustion systems for Internal Combustion Engines (ICE) is guided by the necessity of improving engine efficiency while achieving the pollutant regulations. In this framework, this study identifies and describes the effect of the bore-to-stroke ratio (B/S) on the combustion system performance and emissions by means of computational fluid dynamics (CFD). The study is applied to a 4-cylinder 4-stroke High Speed Direct Injection (HSDI) CI engine. It is divided in two parts, the first part is focused on one operating point and presents a detailed description of the main effects of different B/S ratios configurations, and the second part compares the results with different engine operating conditions. For both parts the air management, injection settings and compression ratio were kept constant in order to isolate the impact of the B/S ratio. The results confirmed that the indicated thermal efficiency was increased for lower B/S ratio because of the combustion chamber surface area decrease and faster combustion. Regarding the emissions, NOx and soot presented a strong and opposed dependence on B/S ratio generated mostly due to enhanced air¿fuel mixing for lower B/S ratio. Finally, those trends were proven to be independent from the operating condition, giving the study a more general value.Authors acknowledge that this work was possible thanks to the Ayuda para la Formation de Profesorado Universitario (FPU 13/02817) belonging to the Subprogramas de Formacion y de Movilidad del Ministerio de Educacion, Cultura y Deporte from Spain. The authors would also like to recognize the funding and technical support from PSA GroupeBenajes, J.; Novella Rosa, R.; Pastor Enguídanos, JM.; Hernández-López, A.; Duverger, T. (2017). A computational analysis of the impact of bore-to-stroke ratio on emissions and efficiency of a HSDI engine. Applied Energy. 205:903-910. https://doi.org/10.1016/j.apenergy.2017.08.023S90391020

Intravitreal, retinal, and central nervous system foscarnet concentrations after rapid intravenous administration to rabbits

Retinal, vitreous humor, brain, and cerebrospinal fluid (CSF) foscarnet levels were measured by high-performance liquid chromatography after administration of an intravenous dose of 120 mg/kg of body weight to 32 pigmented rabbits. A pharmacokinetic analysis was done using a two- compartment model. The penetration ratios, defined as ratios of retinal, vitreous humor, brain, and CSF areas under the concentration-time curve from 0 to 2 h were 110% ± 1%, 12.3% ± 0.7%, 118% ± 1%, and 20.2% ± 2.2%, respectively. These results suggest a good penetration of foscarnet into the retinal and brain tissues, reaching higher concentrations than those estimated from vitreous humor and CSF levels.Comisóión Interministerial de Ciencia y Tecnología SAF97-0012Consejería de Salud Junta de Andalucía 64/9

A quasi-malmquist productivity index

The Malmquist productivity index is based on distance functions, which are reciprocals of radial Debreu-Farrell efficiency measures, and which have a number of desirable properties. Linear programming techniques are frequently employed to calculate the efficiency measures. However these techniques can leave slacks, which constitute a non-radial form of inefficiency which is not incorporated into the analysis. Thus a radial efficiency measure overstates true efficiency, the reciprocal distance function understates the distance to the relevant efficient subset, and the Malmquist productivity index is adversely affected, although in an analytically indeterminate direction. This has led us to consider a new definition of "one-sided" efficiency, and to develop a new nonradial efficiency measure which incorporates all slacks on the selected side. Replacing conventional radial efficiency measures with our new non-radial efficiency measures generates what we call a quasi Malmquist productivity index. We illustrate our quasi-Malmquist productivity index with an application to productivity change in Spanish banking

Diplopia Is Frequent and Associated with Motor and Non-Motor Severity in Parkinson’s Disease: Results from the COPPADIS Cohort at 2-Year Follow-Up

[Background and objective] Diplopia is relatively common in Parkinson’s disease (PD) but is still understudied. Our aim was to analyze the frequency of diplopia in PD patients from a multicenter Spanish cohort, to compare the frequency with a control group, and to identify factors associated with it.[Patients and Methods] PD patients who were recruited from January 2016 to November 2017 (baseline visit; V0) and evaluated again at a 2-year ± 30 days follow-up (V2) from 35 centers of Spain from the COPPADIS cohort were included in this longitudinal prospective study. The patients and controls were classified as “with diplopia” or “without diplopia” according to item 15 of the Non-Motor Symptoms Scale (NMSS) at V0, V1 (1-year ± 15 days), and V2 for the patients and at V0 and V2 for the controls.[Results] The frequency of diplopia in the PD patients was 13.6% (94/691) at V0 (1.9% in controls [4/206]; p < 0.0001), 14.2% (86/604) at V1, and 17.1% (86/502) at V2 (0.8% in controls [1/124]; p < 0.0001), with a period prevalence of 24.9% (120/481). Visual hallucinations at any visit from V0 to V2 (OR = 2.264; 95%CI, 1.269–4.039; p = 0.006), a higher score on the NMSS at V0 (OR = 1.009; 95%CI, 1.012–1.024; p = 0.015), and a greater increase from V0 to V2 on the Unified Parkinson’s Disease Rating Scale–III (OR = 1.039; 95%CI, 1.023–1.083; p < 0.0001) and Neuropsychiatric Inventory (OR = 1.028; 95%CI, 1.001–1.057; p = 0.049) scores were independent factors associated with diplopia (R2 = 0.25; Hosmer and Lemeshow test, p = 0.716).[Conclusions] Diplopia represents a frequent symptom in PD patients and is associated with motor and non-motor severity.Martínez-Martin P. has received honoraria from National School of Public Health (ISCIII), Editori-al Viguera and Takeda Pharmaceuticals for lecturing in courses, and from the International Parkinson and Movement Disorder Society (MDS) for management of the Program on Rating Scales. Mir P. has received honoraria from AbbVie, Abbott, Allergan, Bial, Merz, UCB, and Zambon and have received grants from the Spanish Ministry of Economy and Competitiveness [PI16/01575], co-founded by ISCIII (Subdirección General de Evaluación y Fomento de la Investigación) and by Fondo Europeo de Desarrollo Regional (FEDER), the Consejería de Economía, Innovación, Ciencia y Empleo de la Junta de Andalucía [CVI-02526, CTS-7685], the Consejería de Salud y Bienestar Social de la Junta de Andalucía [ PI-0437-2012, PI-0471-2013], the Sociedad Andaluza de Neurología, the Jacques and Gloria Gossweiler Foundation, the Fundación Alicia Koplowitz, the Fundación Mutua Madrileña.Peer reviewe

Polarimetric Plasmonic Sensing with Bowtie Nanoantenna Arrays

We propose a polarimetric plasmonic biosensor based on bowtie nanoantenna array transducers. Through numerical simulations, based on the finite element method (FEM), we study the phase retardation between the components of light polarized parallel and perpendicular to the major axis of the bowties within the arrays. From a design for high volumetric sensitivity at a wavelength of 780 nm, sensitivities ∼5 rad/RIU is obtained, corresponding to a detection limit of ∼10−7 when using a polarimetric readout platform. Similarly, surface sensitivity of the same array is evaluated by simulating the phase retardation changes induced by the coverage of bioreceptors and analytes of the metallic nanostructures

In vivo cholinergic basal forebrain degeneration and cognition in Parkinson's disease: Imaging results from the COPPADIS study

COPPADIS Study Group.[Introduction] We aimed to assess associations between multimodal neuroimaging measures of cholinergic basal forebrain (CBF) integrity and cognition in Parkinson's disease (PD) without dementia.[Methods] The study included a total of 180 non-demented PD patients and 45 healthy controls, who underwent structural MRI acquisitions and standardized neurocognitive assessment through the PD-Cognitive Rating Scale (PD-CRS) within the multicentric COPPADIS-2015 study. A subset of 73 patients also had Diffusion Tensor Imaging (DTI) acquisitions. Volumetric and microstructural (mean diffusivity, MD) indices of CBF degeneration were automatically extracted using a stereotactic CBF atlas. For comparison, we also assessed multimodal indices of hippocampal degeneration. Associations between imaging measures and cognitive performance were assessed using linear models.[Results] Compared to controls, CBF volume was not significantly reduced in PD patients as a group. However, across PD patients lower CBF volume was significantly associated with lower global cognition (PD-CRStotal: r = 0.37, p < 0.001), and this association remained significant after controlling for several potential confounding variables (p = 0.004). Analysis of individual item scores showed that this association spanned executive and memory domains. No analogue cognition associations were observed for CBF MD. In covariate-controlled models, hippocampal volume was not associated with cognition in PD, but there was a significant association for hippocampal MD (p = 0.02).[Conclusions] Early cognitive deficits in PD without dementia are more closely related to structural MRI measures of CBF degeneration than hippocampal degeneration. In our multicentric imaging acquisitions, DTI-based diffusion measures in the CBF were inferior to standard volumetric assessments for capturing cognition-relevant changes in non-demented PD.This work was supported by the Alzheimer Forschung Initiative e.V. (AFI International Training Grant to MJG), the Instituto de Salud Carlos III-Fondo Europeo de Desarrollo Regional (ISCIII-FEDER) [PI14/01823, PI16/01575, PI18/01898, PI19/01576, PI20/00613], the Consejería de Economía, Innovación, Ciencia y Empleo de la Junta de Andalucía [CVI-02526, CTS-7685], the Consejería de Salud y Bienestar Social de la Junta de Andalucía [PI-0471-2013, PE-0210-2018, PI-0459-2018, PE-0186-2019], the Fundación Alicia Koplowitz and the Fundación “Curemos el Parkinson” (https://www.curemoselparkinson.org). MJG is supported by the “Miguel Servet” program [CP19/00031], MALE by the University of Seville [USE-20046-J], JFM by the “Sara Borrell” program [CD13/00229] and VI-PPIT-US from the University of Seville [USE-18817-A], SJ by the “Acción B-Clínicos-Investigadores” program [B-0007-2019], and DMG by the “Río Hortega” program [CM18/00142].Peer reviewe