A Parallel Application of Matheuristics in Data Envelopment Analysis

Data Envelopment Analysis (DEA) is a non-parametric methodology for estimating technical efficiency and benchmarking. In general, it is desirable that DEA generates the efficient closest targets as benchmarks for each assessed unit. This may be achieved through the application of the Principle of Least Action. However, the mathematical models associated with this principle are based fundamentally on combinatorial NP-hard problems, difficult to be solved. For this reason, this paper uses a parallel matheuristic algorithm, where metaheuristics and exact methods work together to find optimal solutions. Several parallel schemes are used in the algorithm, being possible for them to be configured at different stages of the algorithm. The main intention is to divide the number of problems to be evaluated in equal groups, so that they are resolved in different threads. The DEA problems to be evaluated in this paper are independent of each other, an indispensable requirement for this algorithm. In addition, taking into account that the main algorithm uses exact methods to solve the mathematical problems, different optimization software has been evaluated to compare their performance when executed in parallel. The method is competitive with exact methods, obtaining fitness close to the optimum with low computational time.J. Aparicio and M. González thank the financial support from the Spanish ‘Ministerio de Economía, Industria y Competitividad’ (MINECO), the ‘Agencia Estatal de Investigacion’ and the ‘Fondo Europeo de Desarrollo Regional’ under grant MTM2016-79765-P (AEI/FEDER, UE)

A parameterized scheme of metaheuristics with exact methods for determining the Principle of Least Action in Data Envelopment Analysis

Data Envelopment Analysis (DEA) is a nonparametric methodology for estimating technical efficiency of a set of Decision Making Units (DMUs) from a dataset of inputs and outputs. This paper is devoted to computational aspects of DEA models under the application of the Principle of Least Action. This principle guarantees that the efficient closest targets are determined as benchmarks for each assessed unit. Usually, these models have been addressed in the literature by applying unsatisfactory techniques, based fundamentally on combinatorial NPhard problems. Recently, some heuristics have been developed to partially solve these DEA models. This paper improves the heuristic methods used in previous works by applying a combination of metaheuristics and an exact method. Also, a parameterized scheme of metaheuristics is developed in order to implement metaheuristics and hybridations/combinations, adapting them to the particular problem proposed here. In this scheme, some parameters are used to study several types of metaheuristics, like Greedy Random Adaptative Search Procedure, Genetic Algorithms or Scatter Search. The exact method is included inside the metaheuristic to solve the particular model presented in this paper. A hyperheuristic is used on top of the parameterized scheme in order to search, in the space of metaheuristics, for metaheuristics that provide solutions close to the optimum. The method is competitive with exact methods, obtaining fitness close to the optimum with low computational timeJ. Aparicio and M. González thank the financial support from the Spanish ‘Ministerio de Economa, Industria y Competitividad’ (MINECO), the ‘Agencia Estatal de Investigacion’ and the ‘Fondo Europeo de Desarrollo Regional’ under grant MTM2016-79765-P (AEI/FEDER, UE).Additionally, D. Giméenez thanks the financial support from the Spanish MINECO, as well as by European Commission FEDER funds, under grant TIN2015-66972-C5-3-R

Distância anogenital das mulheres e a relação com a exposição pré-natal da mãe

Anogenital distance (AGD) is a genital development marker which is a sexually dimorphic trait in mammals. Different experimental studies have shown that AGD at birth reflects the androgen exposure of the fetus during its in-utero development. The object of our study was to examine the relation between maternal prenatal exposures to different substances and compounds used on a daily basis during pregnancy and AGD of their daughters as an indirect marker of the intrauterine hormonal environment. This is a cross-sectional study of 100 healthy female undergraduates of ages ranging from 18 to 23. Every participant was subjected to a full gynecological examination, where two AGD variants were measured: AGDAC (anus-clitoris) and AGDAF (anus-fourchette). Both the young women and their mothers completed an epidemiological questionnaire on lifestyles, including prenatal exposure to products and gynecological history. Multiple linear and logistic regression analysis was used to study the relation between the mothers’ exposure to products and their daughters’ AGD. A longer AGDAF in the daughters was significantly associated with a higher prenatal exposure of their mothers to insecticides/pesticides and solvents/degreasers (aOR: 3.9; IC 95%: 1.2, 12.7 and 3.8; IC 95%: 1.1-12.6, respectively). Our results show that certain prenatal environmental exposures of mothers might be associated with significant variations of their daughters’ AGD, a sensitive biomarker that reflects androgen fetal exposure during in-utero development.La distancia anogenital (DAG) es un marcador de desarrollo genital que presenta un dimorfismo sexual en mamíferos. Diversos estudios experimentales han mostrado que la DAG al nacimiento refleja la exposición androgénica a la que el feto ha estado expuesto durante su desarrollo intraútero. El objetivo de nuestro estudio fue explorar la relación entre exposiciones prenatales (maternas) a distintos productos o sustancias de uso cotidiano durante el embarazo y la DAG de sus hijas como marcador indirecto del ambiente hormonal intrauterino. Se trata de un estudio transversal que incluyó 100 jóvenes universitarias sanas entre 18 y 23 años. A cada participante se le realizó un examen ginecológico completo y se midieron dos variantes de DAG: ano-clítoris (DAGAC) y ano-horquilla vulvar (DAGAH). Tanto las jóvenes como sus madres completaron un cuestionario epidemiológico sobre estilos de vida, incluyendo exposición a productos prenatales e historia ginecológica. Las asociaciones entre la exposición a productos prenatales y las DAG de las hijas se realizaron mediante análisis de regresión lineal y logística múltiple. Una mayor exposición materna a insecticidas/plaguicidas y disolventes/desengrasantes se asoció significativamente con una DAGAH alargada en las hijas (ORa: 3,9; IC 95 % 1,2,- 12,7 y 3,8; IC 95 % 1,1 - 12,6, respectivamente). Nuestros resultados respaldan que ciertas exposiciones prenatales maternas ambientales podrían estar asociadas con variaciones significativas de las DAG en sus hijas, un biomarcador que refleja la exposición androgénica fetal durante el desarrollo intraútero.Distância anogenital (AGD) é um traço de dimorfismo sexual em mamíferos. Diversos estudos experimentais em animais sugerem que a AGD ao nascer reflete as concentrações de andrógenos a que o feto terá sido exposto durante o desenvolvimento uterino. O objetivo deste estudo é analisar as associações entre a exposição pré-natal da mãe a diferentes substâncias e compostos de uso quotidiano durante a gravidez e a AGD das suas filhas, como um marcador indireto do ambiente hormonal durante o desenvolvimento no útero. É um estudo transversal efetuado a 100 voluntárias, saudáveis, em idade universitária (18-23 anos) no sul da Espanha. Realizou-se um exame ginecológico completo a cada participante, tendo-se medido as diferenças da AGD: ânus- clitóris (AGDAC) e ânus-freio dos pequenos lábios (AGDAF). Foi também aplicado um questionário epidemiológico, tanto às jovens participantes como as suas mães, acerca dos estilos de vida, história ginecológica, incluindo a exposição a produtos na fase pré- natal. Para verificar a associação entre os produtos pré-natais e as AGD das filhas, foi usada a análise de regressão linear múltipla e a análise de regressão logística. Uma maior exposição materna a inseticidas/pesticidas e solventes teve uma associação significativa com uma AGDAF alargada nas filhas (ORa: 3,9; IC 95 % 1,2, 12,7 e 3,8; IC 95 % 1,1, 12,6, respetivamente). Os nossos resultados sugerem que determinadas exposições ambientais da mãe na fase pré-natal podem estar associadas com variações significativas das AGD das filhas, um biomarcador que reflete as concentrações de andrógenos durante o desenvolvimento uterino

Factors associated with the need of parenteral nutrition in critically ill patients after the initiation of enteral nutrition therapy

Background and aimsDespite enteral nutrition (EN) is the preferred route of nutrition in patients with critical illness, EN is not always able to provide optimal nutrient provision and parenteral nutrition (PN) is needed. This is strongly associated with gastrointestinal (GI) complications, a feature of gastrointestinal dysfunction and disease severity. The aim of the present study was to investigate factors associated with the need of PN after start of EN, together with the use and complications associated with EN.MethodsAdult patients admitted to 38 Spanish intensive care units (ICUs) between April and July 2018, who needed EN therapy were included in a prospective observational study. The characteristics of EN-treated patients and those who required PN after start EN were analyzed (i.e., clinical, laboratory and scores).ResultsOf a total of 443 patients, 43 (9.7%) received PN. One-third (29.3%) of patients presented GI complications, which were more frequent among those needing PN (26% vs. 60%, p = 0.001). No differences regarding mean energy and protein delivery were found between patients treated only with EN (n = 400) and those needing supplementary or total PN (n = 43). Abnormalities in lipid profile, blood proteins, and inflammatory markers, such as C-Reactive Protein, were shown in those patients needing PN. Sequential Organ Failure Assessment (SOFA) on ICU admission (Hazard ratio [HR]:1.161, 95% confidence interval [CI]:1.053–1.281, p = 0.003) and modified Nutrition Risk in Critically Ill (mNUTRIC) score (HR:1.311, 95% CI:1.098–1.565, p = 0.003) were higher among those who needed PN. In the multivariate analysis, higher SOFA score (HR:1.221, 95% CI:1.057–1.410, p = 0.007) and higher triglyceride levels on ICU admission (HR:1.004, 95% CI:1.001–1.007, p = 0.003) were associated with an increased risk for the need of PN, whereas higher albumin levels on ICU admission (HR:0.424, 95% CI:0.210–0.687, p = 0.016) was associated with lower need of PN.ConclusionA higher SOFA and nutrition-related laboratory parameters on ICU admission may be associated with the need of PN after starting EN therapy. This may be related with a higher occurrence of GI complications, a feature of GI dysfunction.Clinical trial registrationClinicalTrials.gov: NCT03634943

Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London

Surgical site infection after gastrointestinal surgery in high-income, middle-income, and low-income countries: a prospective, international, multicentre cohort study

Background: Surgical site infection (SSI) is one of the most common infections associated with health care, but its importance as a global health priority is not fully understood. We quantified the burden of SSI after gastrointestinal surgery in countries in all parts of the world. Methods: This international, prospective, multicentre cohort study included consecutive patients undergoing elective or emergency gastrointestinal resection within 2-week time periods at any health-care facility in any country. Countries with participating centres were stratified into high-income, middle-income, and low-income groups according to the UN's Human Development Index (HDI). Data variables from the GlobalSurg 1 study and other studies that have been found to affect the likelihood of SSI were entered into risk adjustment models. The primary outcome measure was the 30-day SSI incidence (defined by US Centers for Disease Control and Prevention criteria for superficial and deep incisional SSI). Relationships with explanatory variables were examined using Bayesian multilevel logistic regression models. This trial is registered with ClinicalTrials.gov, number NCT02662231. Findings: Between Jan 4, 2016, and July 31, 2016, 13 265 records were submitted for analysis. 12 539 patients from 343 hospitals in 66 countries were included. 7339 (58·5%) patient were from high-HDI countries (193 hospitals in 30 countries), 3918 (31·2%) patients were from middle-HDI countries (82 hospitals in 18 countries), and 1282 (10·2%) patients were from low-HDI countries (68 hospitals in 18 countries). In total, 1538 (12·3%) patients had SSI within 30 days of surgery. The incidence of SSI varied between countries with high (691 [9·4%] of 7339 patients), middle (549 [14·0%] of 3918 patients), and low (298 [23·2%] of 1282) HDI (p < 0·001). The highest SSI incidence in each HDI group was after dirty surgery (102 [17·8%] of 574 patients in high-HDI countries; 74 [31·4%] of 236 patients in middle-HDI countries; 72 [39·8%] of 181 patients in low-HDI countries). Following risk factor adjustment, patients in low-HDI countries were at greatest risk of SSI (adjusted odds ratio 1·60, 95% credible interval 1·05–2·37; p=0·030). 132 (21·6%) of 610 patients with an SSI and a microbiology culture result had an infection that was resistant to the prophylactic antibiotic used. Resistant infections were detected in 49 (16·6%) of 295 patients in high-HDI countries, in 37 (19·8%) of 187 patients in middle-HDI countries, and in 46 (35·9%) of 128 patients in low-HDI countries (p < 0·001). Interpretation: Countries with a low HDI carry a disproportionately greater burden of SSI than countries with a middle or high HDI and might have higher rates of antibiotic resistance. In view of WHO recommendations on SSI prevention that highlight the absence of high-quality interventional research, urgent, pragmatic, randomised trials based in LMICs are needed to assess measures aiming to reduce this preventable complication

Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study

Background Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide.Methods A multimethods analysis was performed as part of the GlobalSurg 3 study-a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital.Findings Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3.85 [95% CI 2.58-5.75]; p&lt;0.0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63.0% vs 82.7%; OR 0.35 [0.23-0.53]; p&lt;0.0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer.Interpretation Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised

Benchmarking in Data Envelopment Analysis: An Approach Based on Genetic Algorithms and Parallel Programming

Data Envelopment Analysis (DEA) is a nonparametric technique to estimate the current level of efficiency of a set of entities. DEA also provides information on how to remove inefficiency through the determination of benchmarking information. This paper is devoted to study DEA models based on closest efficient targets, which are related to the shortest projection to the production frontier and allow inefficient firms to find the easiest way to improve their performance. Usually, these models have been solved by means of unsatisfactory methods since all of them are related in some sense to a combinatorial NP-hard problem. In this paper, the problem is approached by genetic algorithms and parallel programming. In addition, to produce reasonable solutions, a particular metaheuristic is proposed and checked through some numerical instances

Distância anogenital das mulheres e a relação com a exposição pré-natal da mãe

La distancia anogenital (DAG) es un marcador de desarrollo genital que presenta un dimorfismo sexual en mamíferos. Diversos estudios experimentales han mostrado que la DAG al nacimiento refleja la exposición androgénica a la que el feto ha estado expuesto durante su desarrollo intraútero. El objetivo de nuestro estudio fue explorar la relación entre exposiciones prenatales (maternas) a distintos productos o sustancias de uso cotidiano durante el embarazo y la DAG de sus hijas como marcador indirecto del ambiente hormonal intrauterino. Se trata de un estudio transversal que incluyó 100 jóvenes universitarias sanas entre 18 y 23 años. A cada participante se le realizó un examen ginecológico completo y se midieron dos variantes de DAG: ano-clítoris (DAGAC) y ano-horquilla vulvar (DAGAH). Tanto las jóvenes como sus madres completaron un cuestionario epidemiológico sobre estilos de vida, incluyendo exposición a productos prenatales e historia ginecológica. Las asociaciones entre la exposición a productos prenatales y las DAG de las hijas se realizaron mediante análisis de regresión lineal y logística múltiple. Una mayor exposición materna a insecticidas/plaguicidas y disolventes/desengrasantes se asoció significativamente con una DAGAH alargada en las hijas (ORa: 3,9; IC 95 % 1,2,- 12,7 y 3,8; IC 95 % 1,1 - 12,6, respectivamente). Nuestros resultados respaldan que ciertas exposiciones prenatales maternas ambientales podrían estar asociadas con variaciones significativas de las DAG en sus hijas, un biomarcador que refleja la exposición androgénica fetal durante el desarrollo intraútero.Anogenital distance (AGD) is a genital development marker which is a sexually dimorphic trait in mammals. Different experimental studies have shown that AGD at birth reflects the androgen exposure of the fetus during its in-utero development. The object of our study was to examine the relation between maternal prenatal exposures to different substances and compounds used on a daily basis during pregnancy and AGD of their daughters as an indirect marker of the intrauterine hormonal environment. This is a cross-sectional study of 100 healthy female undergraduates of ages ranging from 18 to 23. Every participant was subjected to a full gynecological examination, where two AGD variants were measured: AGDAC (anus-clitoris) and AGDAF (anus-fourchette). Both the young women and their mothers completed an epidemiological questionnaire on lifestyles, including prenatal exposure to products and gynecological history. Multiple linear and logistic regression analysis was used to study the relation between the mothers’ exposure to products and their daughters’ AGD. A longer AGDAF in the daughters was significantly associated with a higher prenatal exposure of their mothers to insecticides/pesticides and solvents/degreasers (aOR: 3.9; IC 95%: 1.2, 12.7 and 3.8; IC 95%: 1.1-12.6, respectively). Our results show that certain prenatal environmental exposures of mothers might be associated with significant variations of their daughters’ AGD, a sensitive biomarker that reflects androgen fetal exposure during in-utero development.Distância anogenital (AGD) é um traço de dimorfismo sexual em mamíferos. Diversos estudos experimentais em animais sugerem que a AGD ao nascer reflete as concentrações de andrógenos a que o feto terá sido exposto durante o desenvolvimento uterino. O objetivo deste estudo é analisar as associações entre a exposição pré-natal da mãe a diferentes substâncias e compostos de uso quotidiano durante a gravidez e a AGD das suas filhas, como um marcador indireto do ambiente hormonal durante o desenvolvimento no útero. É um estudo transversal efetuado a 100 voluntárias, saudáveis, em idade universitária (18-23 anos) no sul da Espanha. Realizou-se um exame ginecológico completo a cada participante, tendo-se medido as diferenças da AGD: ânus- clitóris (AGDAC) e ânus-freio dos pequenos lábios (AGDAF). Foi também aplicado um questionário epidemiológico, tanto às jovens participantes como as suas mães, acerca dos estilos de vida, história ginecológica, incluindo a exposição a produtos na fase pré- natal. Para verificar a associação entre os produtos pré-natais e as AGD das filhas, foi usada a análise de regressão linear múltipla e a análise de regressão logística. Uma maior exposição materna a inseticidas/pesticidas e solventes teve uma associação significativa com uma AGDAF alargada nas filhas (ORa: 3,9; IC 95 % 1,2, 12,7 e 3,8; IC 95 % 1,1, 12,6, respetivamente). Os nossos resultados sugerem que determinadas exposições ambientais da mãe na fase pré-natal podem estar associadas com variações significativas das AGD das filhas, um biomarcador que reflete as concentrações de andrógenos durante o desenvolvimento uterino

PANACEA cough sound-based diagnosis of COVID-19 for the DiCOVA 2021 Challenge

The COVID-19 pandemic has led to the saturation of public health services worldwide. In this scenario, the early diagnosis of SARS-Cov-2 infections can help to stop or slow the spread of the virus and to manage the demand upon health services. This is especially important when resources are also being stretched by heightened demand linked to other seasonal diseases, such as the flu. In this context, the organisers of the DiCOVA 2021 challenge have collected a database with the aim of diagnosing COVID-19 through the use of coughing audio samples. This work presents the details of the automatic system for COVID-19 detection from cough recordings presented by team PANACEA. This team consists of researchers from two European academic institutions and one company: EURECOM (France), University of Granada (Spain), and Biometric Vox S.L. (Spain). We developed several systems based on established signal processing and machine learning methods. Our best system employs a Teager energy operator cepstral coefficients (TECCs) based frontend and Light gradient boosting machine (LightGBM) backend. The AUC obtained by this system on the test set is 76.31% which corresponds to a 10% improvement over the official baseline.Comment: Accepted in INTERSPEECH 202