A note on measuring group performance over time with pseudo-panels

Aparicio et al. (2017) recently extended the Camanho and Dyson (2006) Malmquist-type index (CDMI) for determining group performance in cross-sectional studies to panel or pseudo-panel databases. In that paper, it was shown that the pseudo-panel Malmquist index (PPMI) can be easily interpreted as the ratio of aggregated productivity changes in two groups of decision making units over time if and only if a new -difficult to interpret- term, the so called ‘divergence component’ (DC), is equal to one. The aim of this paper is twofold. First, based upon considering a baseline group technology we define a new base-group base-period PPMI where the DC always vanished. Second, when more than two groups are analyzed we show that under this framework the new base-group base-period PPMI, the new base-group CDMI and the components of both indexes satisfy the circular relation. As a consequence, the complicated ‘adjusted index’ defined in Camanho and Dyson (2006) for measuring the technology gap to satisfy the circular relation also vanishes. Both results will make it easier for practitioners applying the two indexes in different economic sectors regardless of how many groups are being compared

An augmented filled function for global nonlinear integer optimization

The problem of finding global minima of nonlinear discrete functions arises in many fields of practical matters. In recent years, methods based on discrete filled functions have become popular as ways of solving these sort of problems. However, they rely on the steepest descent method for local searches. Here, we present an approach that does not depend on a particular local optimization method, and a new discrete filled function with the useful property that a good continuous global optimization algorithm applied to it leads to an approximation of the solution of the nonlinear discrete problem (Theorem 4). Numerical results are given showing the efficiency of the new approach.Fil: Di Mauro Aparicio, Juan Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Investigación en Ciencias de la Computación. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Investigación en Ciencias de la Computación; ArgentinaFil: Scolnik, Hugo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Investigación en Ciencias de la Computación. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Investigación en Ciencias de la Computación; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Computación; Argentin

Integral use of sugarcane vinasse for biomass production of actinobacteria: Potential application in soil remediation

The use of living actinobacteria biomass to clean up contaminated soils is an attractive biotechnology approach. However, biomass generation from cheap feedstock is the first step to ensure process sustainability. The present work reports the ability of four actinobacteria, Streptomyces sp. M7, MC1, A5, and Amycolatopsis tucumanensis, to generate biomass from sugarcane vinasse. Optimal vinasse concentration to obtain the required biomass (more than 0.4 g L−1) was 20% for all strains, either grown individually or as mixed cultures. However, the biomass fraction recovered from first vinasse was discarded as it retained trace metals present in the effluent. Fractions recovered from three consecutive cycles of vinasse re-use obtained by mixing equal amounts of biomass from single cultures or produced as a mixed culture were evaluated to clean up contaminated soil with lindane and chromium. In all cases, the decrease in pesticide was about 50% after 14 d of incubation. However, chromium removal was statistically different depending on the preparation methodology of the inoculum. While the combined actinobacteria biomass recovered from their respective single cultures removed about 85% of the chromium, the mixed culture biomass removed more than 95%. At the end of the reused vinasse cycle, the mixed culture removed more than 70% of the biological oxygen demand suggesting a proportional reduction in the effluent toxicity. These results represent the first integral approach to address a problematic of multiple contaminations, concerning pesticides, heavy metals and a regionally important effluent like vinasse.Fil: Aparicio, Juan Daniel. Universidad Nacional de Tucumán; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Planta Piloto de Procesos Industriales Microbiologicos; ArgentinaFil: Benimeli, Claudia Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Planta Piloto de Procesos Industriales Microbiologicos; Argentina. Universidad Santo Tomás de Aquino; ArgentinaFil: Almeida, César Américo. Universidad Nacional de San Luis; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Química de San Luis. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Química de San Luis; ArgentinaFil: Polti, Marta Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Planta Piloto de Procesos Industriales Microbiologicos; Argentina. Universidad Nacional de Tucumán; ArgentinaFil: Colin, Veronica Leticia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Planta Piloto de Procesos Industriales Microbiologicos; Argentin

A New Malmquist Index Based on a Standard Technology for Measuring Total Factor Productivity Changes

The Malmquist productivity index is one of the best known and most widely used measures in the economic literature to quantify and decompose changes in productivity of multi-input multi-output production processes over time. Two main approaches are used to calculate this index: the adjacent Malmquist index and the base period Malmquist index. No base period is required to calculate the adjacent Malmquist index, but it fails to comply with the circularity property. The base period Malmquist index uses the technology of a base period and is circular, but the base period choice is arbitrary. There is, therefore, a trade-off between the choice of one or other version of the Malmquist index. The aim of this paper is to propose a new total factor productivity index that is simultaneously circular and does not need to resort to a base period or ad hoc reference. To this end, as in other sciences, we propose a new multi-input multi-output reference production technology for use as a standard for measuring and decomposing total factor productivity changes. As discussed, the standard production technology is conceptually attractive. Also, its parameterization is versatile and adaptable to the evolution of a set of firms performing any multi-input multi-output production process. Additionally, the new approach can bring about a true total factor productivity index, which can be decomposed into an output change and an input change. Finally, the new index can be used to decompose the traditional technical change component into a global technical change applicable across the industry under study and a locally specific technical change dependent on the assessed firm

Comparing the evolution of productivity and performance gaps in education systems through DEA: an application to Latin American countries

The main objective of this paper is to propose a tool for measuring the productiv ity and performance gaps across a set of Decision Making Units for monitoring their evolution and analyzing their components over time. To do this, we use the approach proposed by Aparicio and Santín (Eur J Oper Res 267(1):227–235, 2018) which is grounded on a base-group base-period productivity index and Data Envel opment Analysis. Additionally, we propose a new index for measuring the perfor mance gap between two or more groups of production units and its decomposition in efectiveness gap and outcome possibility set gap. As an empirical illustration of the approach, we focus our attention on the educational sector. In particular, we ana lyze six Latin American countries over time. For this purpose, we rely on OECD– PISA data aggregated at school level. Over the period 2006–2018, performance and productivity followed very diferent paths in each country showing that the correla tion between school performance and productivity is very low. Therefore, we sug gest that the simultaneous analysis of performance and productivity gaps together with their evolution over time is a must in order to benchmark countries and monitor improvements and weaknesses in education systems

Proteomic analysis to understand Cr(VI) homeostasis in Streptomyces sp. MC1

Chromium is a heavy metal widely used in a variety of industrial processes (leather tanning, steel production, metal corrosion inhibition). Hexavalent chromium is carcinogenic and presents higher toxicity than trivalent form since Cr(VI) is more water-soluble and mobile than Cr(III). Industrial effluents containing Cr(VI) are released into water courses, mostly without proper treatment, resulting in anthropogenic contamination. Over the last years, bacteria-mediated removal or stabilization of heavy metal into no or less toxic forms has become in an effective biotechnological process. In this sense, several physiological studies on Streptomyces sp. MC1, an actinobacteria isolated from a polluted soil in the province of Tucumán (Argentina), demonstrated be able to grow in presence of Cr(VI) and remove the metal both in liquid medium and contaminated soils. However, the molecular mechanisms involved are unknown in this actinobacteria. MS-based proteomics have become a powerful tool to understand the mechanisms that underlie physiological processes. In the present work, we use MS-based, label-free and quantitative proteomic analyses in order to identify enzymes involves in oxidative stress response caused by the presence of Cr(VI) in our actinobacteria strain MC1. Sampling points for proteomics analyses were established according to the growth of Streptomyces sp. MC1 in minimal medium (MM) amended with Cr(VI) at 50 mg L-1 and MM without the metal (control condition). Cells were harvested after 18 and 24 h of incubation in control condition and MM with Cr(VI) respectively. These sampling points allowed obtaining comparable and metabolically active cells (exponential phase of growth). Cr(VI) removal was 10% at the time that cells were harvested (24 h). A total of 1981 different proteins were detected in the proteome. It represents approximately 22% of the predicted protein sequences for this strain. 518 of these proteins passed our significance parameters which 186 of them were up-regulated in the condition supplemented with Cr(VI). Analysis with the software BlastKOALA showed that up-regulated proteins were distributed in metabolic pathways that result essential for a correct cellular operation. Overall, the proteins were related to carbon and energy metabolism, genetic information processing, oxidative stress response and membrane transports. Interestingly, enzymes from pentose phosphate pathway increasing significantly their abundance in presence of chromium. About, 10 different oxidoreductases enzymes were up-regulated in presence of the metal. Regarding oxidative stress response, key enzymes like superoxide dismutase, catalase, mycothiol synthase, and mycothiol amidase were identified with an increment in their abundance. The proteome analysis performed in Streptomyces sp. MC1 allowed us to identify the proteins involves in the homeostasis of Cr(VI). These results serve as basement to study and improve the heavy metal removal by actinobacteria.Fil: Sineli, Pedro Eugenio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; ArgentinaFil: Aparicio, Juan Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; ArgentinaFil: Pernodet, Jean Luc. Institut de Biologie Intégrative de la Cellule; FranciaFil: Polti, Marta Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; ArgentinaLV Annual SAIB Meeting and XIV PABMB CongressSaltaArgentinaSociedad Argentina de Investigaciones Bioquímica

Predicción del importe de actuaciones de mantenimiento en viviendas y solares ubicados en España usando perceptrones multicapa

La eficiente gestión de los activos inmobiliarios es una de las actividades con mayor demanda en el sector de la ingeniería de la edificación. La determinación y programación de los trabajos de mantenimiento resulta fundamental para que las entidades financieras establezcan el orden de inversión en función del importe presupuestado. Dado que es un proceso de trabajo lento, resulta necesario su optimización. En este trabajo se desarrollan dos perceptrones multicapa (PM) para la determinación del importe económico en los trabajos de mantenimiento en las dos tipologías de activos inmobiliarios de mayor interés para el sector de la edificación: solares y viviendas. En base al entrenamiento con 76casos de estudio para solares y 317para viviendas, se obtuvieron que las configuraciones de PMóptimas fueron las de 6 y 12 nodos, respectivamente, y se determinaron las variables de entrada que más influyen en su comportamiento. Además, los PM presentaron un comportamiento más óptimo con respecto a los de regresión lineal múltiple. Finalmente, se testearon los PM ante 15 casos de estudio nuevos para cada modelo, prediciendo los importes presupuestados para los trabajos de mantenmientocon una desviación inferior al 11% con respecto al valor real en la mayoría de ellosThe effective asset management of real estate is an area of great interest to the building engineering sector as a whole. The determination and programming of maintenance tasks is essential to allow finance entities to establish market order according to a given budget. The process works slowly, and some optimization is generally required. In this paper, two multilayer perceptrons (MLPs) are developed to determine the economic cost of maintenance works in the two types of real estate assetof more interest tobuilding sector: building sites and dwellings. After training using 76case studies for building sites and 317for dwellings, the optimal MLP configurations are shown to have 6 and 12 nodes respectively, and the input variables that most influenced their behavior are also determined. Furthermore, the MLPs showed more optimal behavior than models using multiple linear regression. Finally, the MLPs were tested for 15 new case studies for each model, predicting the budgeted costsof the associated maintenance workswith deviations of less than 11% compared with the actual value in most case

Isolation and use of extremophiles in the determination of biochemical oxygen demand in saline wastewater

Biochemical oxygen demand (BOD) is a useful parameter for assessing the biodegradability of dissolved organic matter in water. At the same time, this parameter is used to evaluate the efficiency with which certain processes remove biodegradable natural organic matter. However, the values of BOD in saline water are very low because NaCl destroy the seed. Therefore the incorporation of a suitable selection of bacteria (which is not always easy to obtain) is required. In this sense the extremophile bacteria, particularly halophilic bacteria or halophytes can contribute to the development of this technique. The objective of this work was to develop a BOD analysis protocol for the analysis of saline effluent. Within this context a halophilic microorganisms was isolated from Salinas del Bebedero, San Luis, Argentina. Salt sample was cultured in agar Dussault and Lachance. Subsequently, the isolated colonies were cultured in medium Dussault and Lachance broth for 7 days at 37ºC with constant stirring (180 rpm). Subsequently the nucleic acid extraction method was performed by Brosius et al., based on the lysis of the cells with glass beads, and 10% SDS. To amplify the variable region V3-V5, 16S rDNA primers described as F344-R915 (Stahl et al, 1991) were used: 344F: 5?- ACG GGG CGC YGCAGCAGG GA-3 ?and 915R: 5?- GTG CTC CCC CGCCAATTC CT-3 ?; Halorubrum salsolis DNA was used as control. The size of the reaction products was characterized on agarose gel 1% and evaluated on an image analyzer. The molecular weight was determined by comparison with molecular weight marker 100 bp DNA Ladder (Promega). The PCR fragments were sequenced by Macrogen (Korea), with Reaction Kit READY PRIMS a model ABI prisma373A sequencer (PE AppliedBiosystems). The sequencing results were analyzed by comparison with 16S rRNA genes databases (GenBank). The organism under study under study showed a 100% identity to gender Haloarcula sp. One milliliter of the strain (106 cell per mL) was used as seed in the BOD analysis protocol. Standard solution of glucose-glutamic acid (BOD = 20 mg L-1) with different concentrations of NaCl (5%, 10%, 20%, 30% and 40%) were used. BOD bottles were incubated at 20 °C for 5 days. No significant differences were found among differents samples, since their organic matter content was similar (CV <2.1%). In conclusion, Haloarcula sp can be used in the determination of BOD in saline effluent.Fil: Grosselli, Melina del Rosario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Química de San Luis. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Química de San Luis; ArgentinaFil: Aparicio, Juan Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Planta Piloto de Procesos Industriales Microbiológicos; ArgentinaFil: Villegas, Liliana Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Química de San Luis. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Química de San Luis; ArgentinaFil: González, Patricia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Química de San Luis. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Química de San Luis; ArgentinaFil: Almeida, César Américo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Química de San Luis. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Química de San Luis; ArgentinaXI Congreso Argentino de Microbiología GeneralCórdobaArgentinaSociedad Argentina de Microbiología Genera

Retrospective analysis of skin complications related to bone-anchored hearing aid implant: association with surgical technique, quality of life, and audiological benefit

Introduction The bone-anchored hearing aid is an effective form of auditory rehabilitation. Due to the nature of the implant, the most common complications are skin related. A number of alternative surgical implantation techniques have been used to reduce the frequency and severity of skin complications, including the U-shaped graft and the linear incision. Objective To assess skin complications and their association with surgical technique, quality of life, and audiological benefit in patients with bone-anchored hearing aids. Methods This was a retrospective study conducted in a tertiary referral center in Bogotá, Colombia. Patients who had been fitted with a bone-anchored hearing aid implant (unilaterally or bilaterally) for at least 6 months were included in the study. The Holgers classification was used to classify skin complications (Grade 0=none; Grade 1=erythema; Grade 2=erythema and discharge; Grade 3=granulation tissue; and Grade 4=inflammation/infection resulting in the removal of the abutment). The Glasgow Benefit Inventory questionnaire was used to determine quality of life, and the Abbreviated Profile of Hearing Aid Benefit questionnaire was used to determine the subjective audiological benefit. Results A total of 37 patients were included in the study (30 with unilateral implants and 7 with bilateral implant). Of the 44 implants evaluated, 31 (70.3%) were associated with skin complications (7 [15.9%] Grade 1; 4 [9.1%] Grade 2; 15 [34.1%] Grade 3, 5 [11.4%] Grade 4). The U-shaped graft was statistically associated with major complications (Grades 3 and 4) compared with the linear incision technique (p=0.045). No statistically significant differences were found between Abbreviated Profile of Hearing Aid Benefit scores and severity of complications. Similarly, no differences were found between Glasgow Benefit Inventory physical health questions and skin complications. Conclusion Despite the high frequency, skin complications did not seem to affect quality of life or subjective audiological benefits of patients with bone-anchored hearing aids.Introdução A prótese auditiva óssea (BAHA, do inglês Bone-Anchored Hearing Aid) é uma forma eficaz de reabilitação auditiva. Devido à natureza do implante, as complicações mais comuns são relacionadas à pele. Várias técnicas alternativas de implantação cirúrgica têm sido utilizadas para reduzir a frequência e a gravidade das complicações cutâneas, incluindo o enxerto em forma de U e a incisão linear. Objetivo Avaliar as complicações cutâneas e sua associação com a técnica cirúrgica, qualidade de vida e benefício audiológico em pacientes com BAHAs. Método Esse é um estudo retrospectivo realizado em um centro terciário de referência em Bogotá, Colômbia. Os pacientes que receberam um implante de BAHA (unilateral ou bilateralmente) durante pelo menos 6 meses foram incluídos no estudo. A classificação de Holgers foi utilizada para classificar as complicações cutâneas (Grau 0=nenhuma, Grau 1=eritema, Grau 2=eritema e secreção, Grau 3=tecido de granulação e Grau 4=inflamação/infecção resultando na remoção da estrutura de apoio). O questionário Glasgow Benefit Inventory (GBI) foi utilizado para determinar a qualidade de vida, e o questionário Abbreviated Profile of Hearing Aid Benefit (APHAB) foi utilizado para determinar o benefício audiológico subjetivo. Resultados Um total de 37 pacientes foi incluído no estudo (30 com implantes unilaterais e 7 com implantes bilaterais). Dos 44 implantes avaliados, 31 (70,3%) foram associados às complicações cutâneas (7 [15,9%] Grau 1; 4 [9,1%] Grau 2; 15 [34,1%] Grau 3, e 5 [11,4%] Grau 4). O enxerto em forma de U foi estatisticamente associado a complicações maiores (Graus 3 e 4) em comparação com a técnica de incisão linear (p=0,045). Não foram encontradas diferenças estatisticamente significativas entre os escores APHAB e gravidade das complicações. Do mesmo modo, não foram encontradas diferenças entre as questões de saúde física pelo questionário GBI e complicações cutâneas. Conclusão Apesar da alta frequência, as complicações cutâneas não parecem afetar a qualidade de vida ou os benefícios audiológicos subjetivos de pacientes com BAHA

Comparing school ownership performance using a pseudo-panel database: A Malmquist-type index approach

In this paper, we propose a different way of using the Malmquist index that allows us to further analyze the relative performance divergences between two groups of decision-making units (DMUs) over time when only a pseudo-panel database is available. To do this, we extend the Camanho and Dyson (2006) one-period Malmquist-type index (CDMI) for a pseudo-panel database with a new pseudo-panel Malmquist index (PPMI). To illustrate the methodology, we apply it to examine how the performance gap between public and private government-dependent secondary schools in the Basque Country (Spain) performed across three PISA waves (2006, 2009 and 2012). The results suggest that performance is persistently and significantly higher for private government-dependent schools than for public schools