44 research outputs found

    Dynamic beamforming for large area scan in array-based photoacoustic microscopy

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    [EN] We explore the use of a beamforming method intended for large-area scanning in optical-resolution photoacoustic microscopy. It has been evaluated in a experimental setup that comprises a low-cost laser diode and a phase array with a 128-elements linear probe. Three different beamforming strategies are discussed: no-beamforming, static beamforming and dynamic beamforming. The method has been tested in gelatine-based phantoms as well as ex-vivo organs. Results show that, compared with the other two, dynamic beamforming increases up to 15dB and homogenizes signal-to-noise ratio (SNR) along images of roughly 1 cm2. The method and system presented here could be the baseline for more advanced array-based systems that leverage the low-cost laser sources for clinical applications.This research has been supported by the Spanish Ministry of Science, Innovation and Universities through grant Juan de la Cierva - Incorporacion (IJC2018-037897-I), and program Proyectos I+D+i 2019 (PID2019-111436RB-C22). Action co-financed by the European Union through the Programa Operativo del Fondo Europeo de Desarrollo Regional (FEDER) of the Comunitat Valenciana 2014-2020 (IDIFEDER/2018/022). A.C. received financial support from Generalitat Valenciana and Universitat Politecnica de Val ` encia through the grants APOSTD/2018/229 and program PAID-10-19, respectively.Cebrecos, A.; García-Garrigós, JJ.; Descals, A.; Jimenez, N.; Benlloch Baviera, JM.; Camarena Femenia, F. (2020). Dynamic beamforming for large area scan in array-based photoacoustic microscopy. IEEE. 1-4. https://doi.org/10.1109/IUS46767.2020.9251519S1

    EEMD-MUSIC-Based Analysis for Natural Frequencies Identification of Structures Using Artificial and Natural Excitations

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    This paper presents a new EEMD-MUSIC- (ensemble empirical mode decomposition-multiple signal classification-) based methodology to identify modal frequencies in structures ranging from free and ambient vibration signals produced by artificial and natural excitations and also considering several factors as nonstationary effects, close modal frequencies, and noisy environments, which are common situations where several techniques reported in literature fail. The EEMD and MUSIC methods are used to decompose the vibration signal into a set of IMFs (intrinsic mode functions) and to identify the natural frequencies of a structure, respectively. The effectiveness of the proposed methodology has been validated and tested with synthetic signals and under real operating conditions. The experiments are focused on extracting the natural frequencies of a truss-type scaled structure and of a bridge used for both highway traffic and pedestrians. Results show the proposed methodology as a suitable solution for natural frequencies identification of structures from free and ambient vibration signals

    Oil Extracted from Coffee Grounds to Obtain Biodiesel as Renewable Energy

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    Biodiesel is one of several alternative fuels as it reduces the amount of greenhouse gases that cause global warming in the world. Coffee consumption produces a by-product called ground coffee, raw material for the oil used in the production of biodiesel. In the investigation, the conversion efficiency of the oil extracted from the coffee grounds into biodiesel was determined, from the obtaining and characterization of the oil extracted from the coffee grounds, which presented a density of 0.875 g/mL, viscosity of 44.7 mm²/s, free fatty acids of 2.729%, acid value of 5.722 mg KOH/g, iodine value 111.672 g I2/100 g and saponification value of 31.422 mg KOH/g. With the extracted oil, biodiesel was obtained by the transesterification process through a completely randomized design analysis, the stirring speed significantly influenced the conversion of the oil to biodiesel, the results obtained under a stirring speed of 100 rpm the conversion was 77.78 % while the biodiesel produced at a stirring speed of 400 rpm the conversion was 92.48 % and presented a density of 0.88 g/mL, viscosity of 5.47 mm²/s, free fatty acids of 0.1605 %, acid value of 0.3366 mg KOH/g and iodine value of 83.754 g I2/100 g. Biodiesel was obtained with good efficiency as an environmentally friendly fuel

    Análisis de la gestión administrativa en la Unidad de Gestión Educativa Local N.° 302, Leoncio Prado

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    Objective: To analyze the administrative management in the Local Educational Management Unit N.° 302, Leoncio Prado. Methods. The research approach was quantitative, while the level was descriptive. A survey was applied to the principals (primary and secondary) that make up the educational staff of the province of Leoncio Prado, who formed the unit of analysis of the study. Results. In the analysis of administrative management, the results were 42.0 % or "regular". Planning yielded results of 46.1 % or "fair". Also, organization yielded results of 47.7 % or "fair". The results for management were 47.2 % or "fair". Finally, the results for control were 47.2 % or "fair". Conclusions. The analysis of the administrative management of the institution was predominantly regular, being the dimensions: planning, organization, direction and control, the ones that presented the greatest deficiencies in the management of the Local Educational Management Unit N.° 302, Leoncio Prado.Objetivo. Analizar la gestión administrativa en la Unidad de Gestión Educativa Local N.° 302, Leoncio Prado. Métodos. El enfoque de investigación fue cuantitativo, mientras que el nivel fue descriptivo. Se aplicó una encuesta a los directores (primaria y secundaria) que conforman el personal educativo de la provincia de Leoncio Prado, quienes formarón la unidad de análisis del estudio. Resultados. En análsiis de la gestión administrativa arrojó resultados del 42,0 % o “regular”. Por su parte, la planeación arrojó resultados del 46,1 % o “regular”. También, la organización arrojó resultados del 47,7 % o “regular”. Referente a la dirección esta arrojó resultados del 47,2 % o “regular”. Finalmente, los resultados del control fueron del 47,2 % o “regular”. Conclusiones. El analisis de la gestión administra de la insttución fue predominantemente regular, siendo las dimensiones: planeación, organización, dirección y control, las que presentaron mayores deficiencias en la gestión de la Unidad de Gestión Educativa Local N.° 302, Leoncio Prado

    Clinical factors associated with a Candida albicans Germ Tube Antibody positive test in Intensive Care Unit patients

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    Background: Poor outcomes of invasive candidiasis (IC) are associated with the difficulty in establishing the microbiological diagnosis at an early stage. New scores and laboratory tests have been developed in order to make an early therapeutic intervention in an attempt to reduce the high mortality associated with invasive fungal infections. Candida albicans IFA IgG has been recently commercialized for germ tube antibody detection (CAGTA). This test provides a rapid and simple diagnosis of IC (84.4% sensitivity and 94.7% specificity). The aim of this study is to identify the patients who could be benefited by the use of CAGTA test in critical care setting. Methods: A prospective, cohort, observational multicentre study was carried out in six medical/surgical Intensive care units (ICU) of tertiary-care Spanish hospitals. Candida albicans Germ Tube Antibody test was performed twice a week if predetermined risk factors were present, and serologically demonstrated candidiasis was considered if the testing serum dilution was >= 1: 160 in at least one sample and no other microbiological evidence of invasive candidiasis was found. Results: Fifty-three critically ill non-neutropenic patients (37.7% post surgery) were included. Twenty-two patients (41.5%) had CAGTA-positive results, none of them with positive blood culture for Candida. Neither corrected colonization index nor antifungal treatment had influence on CAGTA results. This finding could corroborate that the CAGTA may be an important biomarker to distinguish between colonization and infection in these patients. The presence of acute renal failure at the beginning of the study was more frequent in CAGTA-negative patients. Previous surgery was statistically more frequent in CAGTA-positive patients. Conclusions: This study identified previous surgery as the principal clinical factor associated with CAGTA-positive results and emphasises the utility of this promising technique, which was not influenced by high Candida colonization or antifungal treatment. Our results suggest that detection of CAGTA may be important for the diagnosis of invasive candidiasis in surgical patients admitted in ICU.This study has been supported by a Pfizer research gran

    Role of the first WHO mutation catalogue in the diagnosis of antibiotic resistance in Mycobacterium tuberculosis in the Valencia Region, Spain: a retrospective genomic analysis

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    9 páginas, 2 figuras, 1 tablaBackground: In June, 2021, WHO published the most complete catalogue to date of resistance-conferring mutations in Mycobacterium tuberculosis. Here, we aimed to assess the performance of genome-based antimicrobial resistance prediction using the catalogue and its potential for improving diagnostics in a real low-burden setting. Methods: In this retrospective population-based genomic study M tuberculosis isolates were collected from 25 clinical laboratories in the low-burden setting of the Valencia Region, Spain. Culture-positive tuberculosis cases reported by regional public health authorities between Jan 1, 2014, and Dec 31, 2016, were included. The drug resistance profiles of these isolates were predicted by the genomic identification, via whole-genome sequencing (WGS), of the high-confidence resistance-causing variants included in the catalogue and compared with the phenotype. We determined the minimum inhibitory concentration (MIC) of the isolates with discordant resistance profiles using the resazurin microtitre assay. Findings: WGS was performed on 785 M tuberculosis complex culture-positive isolates, and the WGS resistance prediction sensitivities were: 85·4% (95% CI 70·8–94·4) for isoniazid, 73·3% (44·9–92·2) for rifampicin, 50·0% (21·1–78·9) for ethambutol, and 57·1% (34·0–78·2) for pyrazinamide; all specificities were more than 99·6%. Sensitivity values were lower than previously reported, but the overall pan-susceptibility accuracy was 96·4%. Genotypic analysis revealed that four phenotypically susceptible isolates carried mutations (rpoB Leu430Pro and rpoB Ile491Phe for rifampicin and fabG1 Leu203Leu for isoniazid) known to give borderline resistance in standard phenotypic tests. Additionally, we identified three putative resistance-associated mutations (inhA Ser94Ala, katG Leu48Pro, and katG Gly273Arg for isoniazid) in samples with substantially higher MICs than those of susceptible isolates. Combining both genomic and phenotypic data, in accordance with the WHO diagnostic guidelines, we could detect two new multidrug-resistant cases. Additionally, we detected 11 (1·6%) of 706 isolates to be monoresistant to fluoroquinolone, which had been previously undetected. Interpretation: We showed that the WHO catalogue enables the detection of resistant cases missed in phenotypic testing in a low-burden region, thus allowing for better patient-tailored treatment. We also identified mutations not included in the catalogue, relevant at the local level. Evidence from this study, together with future updates of the catalogue, will probably lead in the future to the partial replacement of culture testing with WGS-based drug susceptibility testing in our setting. Funding: European Research Council and the Spanish Ministerio de Ciencia.This project received funding from the European Research Council under the European Union’s Horizon 2020 Research and Innovation Program Grant 101001038 (TB-RECONNECT; awarded to IC), from Ministerio de Ciencia (Spanish Government) Project PID2019-104477RB-I00 (awarded to IC), and from Generalitat Valenciana Project AICO/2018/113 (awarded to IC). AMG-M is funded by a Formación deProfesorado Universitario grant programme (FPU19/04562) from Ministerio de Universidades (Spanish Government). IC is also supported by the European Commission–NextGenerationEU, through Centro Superior de Investigaciones Científicas Global Health Platform (PTI Salud Global). We thank all the members of the Valencia RegionTuberculosis Working Group

    Population-based sequencing of Mycobacterium tuberculosis reveals how current population dynamics are shaped by past epidemics

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    23 páginas, 4 figuras, 1 tabla.Transmission is a driver of tuberculosis (TB) epidemics in high-burden regions, with assumed negligible impact in low-burden areas. However, we still lack a full characterization of transmission dynamics in settings with similar and different burdens. Genomic epidemiology can greatly help to quantify transmission, but the lack of whole genome sequencing population-based studies has hampered its application. Here, we generate a population-based dataset from Valencia region and compare it with available datasets from different TB-burden settings to reveal transmission dynamics heterogeneity and its public health implications. We sequenced the whole genome of 785 Mycobacterium tuberculosis strains and linked genomes to patient epidemiological data. We use a pairwise distance clustering approach and phylodynamic methods to characterize transmission events over the last 150 years, in different TB-burden regions. Our results underscore significant differences in transmission between low-burden TB settings, i.e., clustering in Valencia region is higher (47.4%) than in Oxfordshire (27%), and similar to a high-burden area as Malawi (49.8%). By modeling times of the transmission links, we observed that settings with high transmission rate are associated with decades of uninterrupted transmission, irrespective of burden. Together, our results reveal that burden and transmission are not necessarily linked due to the role of past epidemics in the ongoing TB incidence, and highlight the need for in-depth characterization of transmission dynamics and specifically tailored TB control strategies.European Research Council 638553-TB-ACCELERATE; European Research Council 101001038-TBRECONNECT; Ministerio de Ciencia e Innovación SAF2016-77346-RPeer reviewe

    Accelerated surgery versus standard care in hip fracture (HIP ATTACK): an international, randomised, controlled trial

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    Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

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    Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries
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