17 research outputs found

    Analysis and modeling of CLBG using the transfer matrix

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    Gratings in optical fibers have been increasingly used in a variety of applications such as sensors and Telecomm. Depending on perturbation separation, they are classified as: fiber Bragg gratings (FBG), and long period gratings (LPG), whose each spectral output offer advantages for certain applications. Nowadays there is a great interest in the study of arrays formed by the combination of long period gratings and Bragg gratings in cascade (CLBG), where the propagation modes of the core and the cladding propagate in the Bragg grating after they propagate in the LPG. In this work, analysis and modeling of Cascaded Long Bragg Gratings using the Transfer Matrix method was performed for the case of two gratings in series along one fiber. We analyzed the variation of the FWHM of the reflectance and transmittance spectra for different values of the difference of the refractive indexes of the core and the perturbation of the grating, using the typical core refractive index of an SMF-28 as reference value. For smaller index difference a narrow intensity peak was observed. After the number of perturbations was varied, when there is a greater number of perturbations in the grating, there is greater intensity in reflectance. However, as our results show, this dependence is not a linear function. The results were obtained under the maximum-reflectivity condition (tuned) for each single grating. The development of the mathematical model, the results of the simulation and the analysis of results are part of the development of the present work11103SPIE Optical engineering + applications - Optical modeling and system alignmentAuthors are grateful to UAM-Azcapotzalco, CONACYT, University of Twente and UNICAMP for their suppor

    Long daytime napping is associated with increased adiposity and type 2 diabetes in an elderly population with metabolic syndrome

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    Research examining associations between objectively-measured napping time and type 2 diabetes (T2D) is lacking. This study aimed to evaluate daytime napping in relation to T2D and adiposity measures in elderly individuals from the Mediterranean region. A cross-sectional analysis of baseline data from 2190 elderly participants with overweight/obesity and metabolic syndrome, in the PREDIMED-Plus trial, was carried out. Accelerometer-derived napping was measured. Prevalence ratios (PR) and 95% confidence intervals (CI) for T2D were obtained using multivariable-adjusted Cox regression with constant time. Linear regression models were fitted to examine associations of napping with body mass index (BMI) and waist circumference (WC). Participants napping ≥90 min had a higher prevalence of T2D (PR 1.37 (1.06, 1.78)) compared with those napping 5 to <30 min per day. Significant positive associations with BMI and WC were found in those participants napping ≥30 min as compared to those napping 5 to <30 min per day. The findings of this study suggest that longer daytime napping is associated with higher T2D prevalence and greater adiposity measures in an elderly Spanish population at high cardiovascular risk

    CIBERER : Spanish national network for research on rare diseases: A highly productive collaborative initiative

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    Altres ajuts: Instituto de Salud Carlos III (ISCIII); Ministerio de Ciencia e Innovación.CIBER (Center for Biomedical Network Research; Centro de Investigación Biomédica En Red) is a public national consortium created in 2006 under the umbrella of the Spanish National Institute of Health Carlos III (ISCIII). This innovative research structure comprises 11 different specific areas dedicated to the main public health priorities in the National Health System. CIBERER, the thematic area of CIBER focused on rare diseases (RDs) currently consists of 75 research groups belonging to universities, research centers, and hospitals of the entire country. CIBERER's mission is to be a center prioritizing and favoring collaboration and cooperation between biomedical and clinical research groups, with special emphasis on the aspects of genetic, molecular, biochemical, and cellular research of RDs. This research is the basis for providing new tools for the diagnosis and therapy of low-prevalence diseases, in line with the International Rare Diseases Research Consortium (IRDiRC) objectives, thus favoring translational research between the scientific environment of the laboratory and the clinical setting of health centers. In this article, we intend to review CIBERER's 15-year journey and summarize the main results obtained in terms of internationalization, scientific production, contributions toward the discovery of new therapies and novel genes associated to diseases, cooperation with patients' associations and many other topics related to RD research

    A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)

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    NEOTROPICAL XENARTHRANS: a data set of occurrence of xenarthran species in the Neotropics

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    Xenarthrans – anteaters, sloths, and armadillos – have essential functions for ecosystem maintenance, such as insect control and nutrient cycling, playing key roles as ecosystem engineers. Because of habitat loss and fragmentation, hunting pressure, and conflicts with 24 domestic dogs, these species have been threatened locally, regionally, or even across their full distribution ranges. The Neotropics harbor 21 species of armadillos, ten anteaters, and six sloths. Our dataset includes the families Chlamyphoridae (13), Dasypodidae (7), Myrmecophagidae (3), Bradypodidae (4), and Megalonychidae (2). We have no occurrence data on Dasypus pilosus (Dasypodidae). Regarding Cyclopedidae, until recently, only one species was recognized, but new genetic studies have revealed that the group is represented by seven species. In this data-paper, we compiled a total of 42,528 records of 31 species, represented by occurrence and quantitative data, totaling 24,847 unique georeferenced records. The geographic range is from the south of the USA, Mexico, and Caribbean countries at the northern portion of the Neotropics, to its austral distribution in Argentina, Paraguay, Chile, and Uruguay. Regarding anteaters, Myrmecophaga tridactyla has the most records (n=5,941), and Cyclopes sp. has the fewest (n=240). The armadillo species with the most data is Dasypus novemcinctus (n=11,588), and the least recorded for Calyptophractus retusus (n=33). With regards to sloth species, Bradypus variegatus has the most records (n=962), and Bradypus pygmaeus has the fewest (n=12). Our main objective with Neotropical Xenarthrans is to make occurrence and quantitative data available to facilitate more ecological research, particularly if we integrate the xenarthran data with other datasets of Neotropical Series which will become available very soon (i.e. Neotropical Carnivores, Neotropical Invasive Mammals, and Neotropical Hunters and Dogs). Therefore, studies on trophic cascades, hunting pressure, habitat loss, fragmentation effects, species invasion, and climate change effects will be possible with the Neotropical Xenarthrans dataset

    Analysis and modeling of CLBG using the transfer matrix

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    Gratings in optical fibers have been increasingly used in a variety of applications such as sensors and Telecomm. Depending on perturbation separation, they are classified as: fiber Bragg gratings (FBG), and long period gratings (LPG), whose each spectral output offer advantages for certain applications. Nowadays there is a great interest in the study of arrays formed by the combination of long period gratings and Bragg gratings in cascade (CLBG), where the propagation modes of the core and the cladding propagate in the Bragg grating after they propagate in the LPG. In this work, analysis and modeling of Cascaded Long Bragg Gratings using the Transfer Matrix method was performed for the case of two gratings in series along one fiber. We analyzed the variation of the FWHM of the reflectance and transmittance spectra for different values of the difference of the refractive indexes of the core and the perturbation of the grating, using the typical core refractive index of an SMF-28 as reference value. For smaller index difference a narrow intensity peak was observed. After the number of perturbations was varied, when there is a greater number of perturbations in the grating, there is greater intensity in reflectance. However, as our results show, this dependence is not a linear function. The results were obtained under the maximum-reflectivity condition (tuned) for each single grating. The development of the mathematical model, the results of the simulation and the analysis of results are part of the development of the present work

    Patients with Crohn's disease have longer post-operative in-hospital stay than patients with colon cancer but no difference in complications' rate

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    BACKGROUNDRight hemicolectomy or ileocecal resection are used to treat benign conditions like Crohn's disease (CD) and malignant ones like colon cancer (CC).AIMTo investigate differences in pre- and peri-operative factors and their impact on post-operative outcome in patients with CC and CD.METHODSThis is a sub-group analysis of the European Society of Coloproctology's prospective, multi-centre snapshot audit. Adult patients with CC and CD undergoing right hemicolectomy or ileocecal resection were included. Primary outcome measure was 30-d post-operative complications. Secondary outcome measures were post-operative length of stay (LOS) at and readmission.RESULTSThree hundred and seventy-five patients with CD and 2,515 patients with CC were included. Patients with CD were younger (median = 37 years for CD and 71 years for CC (P &lt; 0.01), had lower American Society of Anesthesiology score (ASA) grade (P &lt; 0.01) and less comorbidity (P &lt; 0.01), but were more likely to be current smokers (P &lt; 0.01). Patients with CD were more frequently operated on by colorectal surgeons (P &lt; 0.01) and frequently underwent ileocecal resection (P &lt; 0.01) with higher rate of de-functioning/primary stoma construction (P &lt; 0.01). Thirty-day post-operative mortality occurred exclusively in the CC group (66/2515, 2.3%). In multivariate analyses, the risk of post-operative complications was similar in the two groups (OR 0.80, 95%CI: 0.54-1.17; P = 0.25). Patients with CD had a significantly longer LOS (Geometric mean 0.87, 95%CI: 0.79-0.95; P &lt; 0.01). There was no difference in re-admission rates. The audit did not collect data on post-operative enhanced recovery protocols that are implemented in the different participating centers.CONCLUSIONPatients with CD were younger, with lower ASA grade, less comorbidity, operated on by experienced surgeons and underwent less radical resection but had a longer LOS than patients with CC although complication's rate was not different between the two groups

    Prevalence and risk factors for delirium in critically ill patients with COVID-19 (COVID-D): a multicentre cohort study

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    Background: To date, 750 000 patients with COVID-19 worldwide have required mechanical ventilation and thus are at high risk of acute brain dysfunction (coma and delirium). We aimed to investigate the prevalence of delirium and coma, and risk factors for delirium in critically ill patients with COVID-19, to aid the development of strategies to mitigate delirium and associated sequelae. Methods: This multicentre cohort study included 69 adult intensive care units (ICUs), across 14 countries. We included all patients (aged 6518 years) admitted to participating ICUs with severe acute respiratory syndrome coronavirus 2 infection before April 28, 2020. Patients who were moribund or had life-support measures withdrawn within 24 h of ICU admission, prisoners, patients with pre-existing mental illness, neurodegenerative disorders, congenital or acquired brain damage, hepatic coma, drug overdose, suicide attempt, or those who were blind or deaf were excluded. We collected de-identified data from electronic health records on patient demographics, delirium and coma assessments, and management strategies for a 21-day period. Additional data on ventilator support, ICU length of stay, and vital status was collected for a 28-day period. The primary outcome was to determine the prevalence of delirium and coma and to investigate any associated risk factors associated with development of delirium the next day. We also investigated predictors of number of days alive without delirium or coma. These outcomes were investigated using multivariable regression. Findings: Between Jan 20 and April 28, 2020, 4530 patients with COVID-19 were admitted to 69 ICUs, of whom 2088 patients were included in the study cohort. The median age of patients was 64 years (IQR 54 to 71) with a median Simplified Acute Physiology Score (SAPS) II of 40\ub70 (30\ub70 to 53\ub70). 1397 (66\ub79%) of 2088 patients were invasively mechanically ventilated on the day of ICU admission and 1827 (87\ub75%) were invasively mechanical ventilated at some point during hospitalisation. Infusion with sedatives while on mechanical ventilation was common: 1337 (64\ub70%) of 2088 patients were given benzodiazepines for a median of 7\ub70 days (4\ub70 to 12\ub70) and 1481 (70\ub79%) were given propofol for a median of 7\ub70 days (4\ub70 to 11\ub70). Median Richmond Agitation\u2013Sedation Scale score while on invasive mechanical ventilation was \u20134 (\u20135 to \u20133). 1704 (81\ub76%) of 2088 patients were comatose for a median of 10\ub70 days (6\ub70 to 15\ub70) and 1147 (54\ub79%) were delirious for a median of 3\ub70 days (2\ub70 to 6\ub70). Mechanical ventilation, use of restraints, and benzodiazepine, opioid, and vasopressor infusions, and antipsychotics were each associated with a higher risk of delirium the next day (all p 640\ub704), whereas family visitation (in person or virtual) was associated with a lower risk of delirium (p&lt;0\ub70001). During the 21-day study period, patients were alive without delirium or coma for a median of 5\ub70 days (0\ub70 to 14\ub70). At baseline, older age, higher SAPS II scores, male sex, smoking or alcohol abuse, use of vasopressors on day 1, and invasive mechanical ventilation on day 1 were independently associated with fewer days alive and free of delirium and coma (all p&lt;0\ub701). 601 (28\ub78%) of 2088 patients died within 28 days of admission, with most of those deaths occurring in the ICU. Interpretation: Acute brain dysfunction was highly prevalent and prolonged in critically ill patients with COVID-19. Benzodiazepine use and lack of family visitation were identified as modifiable risk factors for delirium, and thus these data present an opportunity to reduce acute brain dysfunction in patients with COVID-19. Funding: None. Translations: For the French and Spanish translations of the abstract see Supplementary Materials section

    The impact of stapling technique and surgeon specialism on anastomotic failure after right?sided colorectal resection: an international multicentre, prospective audit

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    Aim There is little evidence to support choice of technique and configuration for stapled anastomoses after right hemicolectomy and ileocaecal resection. This study aimed to determine the relationship between stapling technique and anastomotic failure. Method Any unit performing gastrointestinal surgery was invited to contribute data on consecutive adult patients undergoing right hemicolectomy or ileocolic resection to this prospective, observational, international, multicentre study. Patients undergoing stapled, side?to?side ileocolic anastomoses were identified and multilevel, multivariable logistic regression analyses were performed to explore factors associated with anastomotic leak. Results One thousand three hundred and forty?seven patients were included from 200 centres in 32 countries. The overall anastomotic leak rate was 8.3%. Upon multivariate analysis there was no difference in leak rate with use of a cutting stapler for apical closure compared with a noncutting stapler (8.4% vs 8.0%, OR 0.91, 95% CI 0.54–1.53, P = 0.72). Oversewing of the apical staple line, whether in the cutting group (7.9% vs 9.7%, OR 0.87, 95% CI 0.52–1.46, P = 0.60) or noncutting group (8.9% vs 5.7%, OR 1.40, 95% CI 0.46–4.23, P = 0.55) also conferred no benefit in terms of reducing leak rates. Surgeons reporting to be general surgeons had a significantly higher leak rate than those reporting to be colorectal surgeons (12.1% vs 7.3%, OR 1.65, 95% CI 1.04–2.64, P = 0.04). Conclusion This study did not identify any difference in anastomotic leak rates according to the type of stapling device used to close the apical aspect. In addition, oversewing of the anastomotic staple lines appears to confer no benefit in terms of reducing leak rates. Although general surgeons operated on patients with more high?risk characteristics than colorectal surgeons, a higher leak rate for general surgeons which remained after risk adjustment needs further exploration
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