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Sökning: WFRF:(Mauricio D.)

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1.
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2.
  • Abbafati, Cristiana, et al. (författare)
  • 2020
  • Tidskriftsartikel (refereegranskat)
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3.
  • Flannick, Jason, et al. (författare)
  • Data Descriptor : Sequence data and association statistics from 12,940 type 2 diabetes cases and controls
  • 2017
  • Ingår i: Scientific Data. - : Springer Science and Business Media LLC. - 2052-4463. ; 4
  • Tidskriftsartikel (refereegranskat)abstract
    • To investigate the genetic basis of type 2 diabetes (T2D) to high resolution, the GoT2D and T2D-GENES consortia catalogued variation from whole-genome sequencing of 2,657 European individuals and exome sequencing of 12,940 individuals of multiple ancestries. Over 27M SNPs, indels, and structural variants were identified, including 99% of low-frequency (minor allele frequency [MAF] 0.1-5%) non-coding variants in the whole-genome sequenced individuals and 99.7% of low-frequency coding variants in the whole-exome sequenced individuals. Each variant was tested for association with T2D in the sequenced individuals, and, to increase power, most were tested in larger numbers of individuals (> 80% of low-frequency coding variants in similar to ~82 K Europeans via the exome chip, and similar to ~90% of low-frequency non-coding variants in similar to ~44 K Europeans via genotype imputation). The variants, genotypes, and association statistics from these analyses provide the largest reference to date of human genetic information relevant to T2D, for use in activities such as T2D-focused genotype imputation, functional characterization of variants or genes, and other novel analyses to detect associations between sequence variation and T2D.
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4.
  • Fuchsberger, Christian, et al. (författare)
  • The genetic architecture of type 2 diabetes
  • 2016
  • Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 536:7614, s. 41-47
  • Tidskriftsartikel (refereegranskat)abstract
    • The genetic architecture of common traits, including the number, frequency, and effect sizes of inherited variants that contribute to individual risk, has been long debated. Genome-wide association studies have identified scores of common variants associated with type 2 diabetes, but in aggregate, these explain only a fraction of the heritability of this disease. Here, to test the hypothesis that lower-frequency variants explain much of the remainder, the GoT2D and T2D-GENES consortia performed whole-genome sequencing in 2,657 European individuals with and without diabetes, and exome sequencing in 12,940 individuals from five ancestry groups. To increase statistical power, we expanded the sample size via genotyping and imputation in a further 111,548 subjects. Variants associated with type 2 diabetes after sequencing were overwhelmingly common and most fell within regions previously identified by genome-wide association studies. Comprehensive enumeration of sequence variation is necessary to identify functional alleles that provide important clues to disease pathophysiology, but large-scale sequencing does not support the idea that lower-frequency variants have a major role in predisposition to type 2 diabetes.
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5.
  • Manning, Alisa, et al. (författare)
  • A Low-Frequency Inactivating AKT2 Variant Enriched in the Finnish Population Is Associated With Fasting Insulin Levels and Type 2 Diabetes Risk
  • 2017
  • Ingår i: Diabetes. - : AMER DIABETES ASSOC. - 0012-1797 .- 1939-327X. ; 66:7, s. 2019-2032
  • Tidskriftsartikel (refereegranskat)abstract
    • To identify novel coding association signals and facilitate characterization of mechanisms influencing glycemic traits and type 2 diabetes risk, we analyzed 109,215 variants derived from exome array genotyping together with an additional 390,225 variants from exome sequence in up to 39,339 normoglycemic individuals from five ancestry groups. We identified a novel association between the coding variant (p.Pro50Thr) in AKT2 and fasting plasma insulin (FI), a gene in which rare fully penetrant mutations are causal for monogenic glycemic disorders. The low-frequency allele is associated with a 12% increase in FI levels. This variant is present at 1.1% frequency in Finns but virtually absent in individuals from other ancestries. Carriers of the FI-increasing allele had increased 2-h insulin values, decreased insulin sensitivity, and increased risk of type 2 diabetes (odds ratio 1.05). In cellular studies, the AKT2-Thr50 protein exhibited a partial loss of function. We extend the allelic spectrum for coding variants in AKT2 associated with disorders of glucose homeostasis and demonstrate bidirectional effects of variants within the pleckstrin homology domain of AKT2.
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6.
  • Sumaila, U. Rashid, et al. (författare)
  • WTO must ban harmful fisheries subsidies
  • 2021
  • Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 374:6567, s. 544-544
  • Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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7.
  • Wierenga, Lara M., et al. (författare)
  • Greater male than female variability in regional brain structure across the lifespan
  • 2022
  • Ingår i: Human Brain Mapping. - : John Wiley & Sons. - 1065-9471 .- 1097-0193. ; 43:1, s. 470-499
  • Tidskriftsartikel (refereegranskat)abstract
    • For many traits, males show greater variability than females, with possible implications for understanding sex differences in health and disease. Here, the ENIGMA (Enhancing Neuro Imaging Genetics through Meta-Analysis) Consortium presents the largest-ever mega-analysis of sex differences in variability of brain structure, based on international data spanning nine decades of life. Subcortical volumes, cortical surface area and cortical thickness were assessed in MRI data of 16,683 healthy individuals 1-90 years old (47% females). We observed significant patterns of greater male than female between-subject variance for all subcortical volumetric measures, all cortical surface area measures, and 60% of cortical thickness measures. This pattern was stable across the lifespan for 50% of the subcortical structures, 70% of the regional area measures, and nearly all regions for thickness. Our findings that these sex differences are present in childhood implicate early life genetic or gene-environment interaction mechanisms. The findings highlight the importance of individual differences within the sexes, that may underpin sex-specific vulnerability to disorders.
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8.
  • Akiyama, Kazunori, et al. (författare)
  • First Sagittarius A* Event Horizon Telescope Results. II. EHT and Multiwavelength Observations, Data Processing, and Calibration
  • 2022
  • Ingår i: Astrophysical Journal Letters. - : American Astronomical Society. - 2041-8213 .- 2041-8205. ; 930:2
  • Tidskriftsartikel (refereegranskat)abstract
    • We present Event Horizon Telescope (EHT) 1.3 mm measurements of the radio source located at the position of the supermassive black hole Sagittarius A* (Sgr A*), collected during the 2017 April 5-11 campaign. The observations were carried out with eight facilities at six locations across the globe. Novel calibration methods are employed to account for Sgr A*'s flux variability. The majority of the 1.3 mm emission arises from horizon scales, where intrinsic structural source variability is detected on timescales of minutes to hours. The effects of interstellar scattering on the image and its variability are found to be subdominant to intrinsic source structure. The calibrated visibility amplitudes, particularly the locations of the visibility minima, are broadly consistent with a blurred ring with a diameter of similar to 50 mu as, as determined in later works in this series. Contemporaneous multiwavelength monitoring of Sgr A* was performed at 22, 43, and 86 GHz and at near-infrared and X-ray wavelengths. Several X-ray flares from Sgr A* are detected by Chandra, one at low significance jointly with Swift on 2017 April 7 and the other at higher significance jointly with NuSTAR on 2017 April 11. The brighter April 11 flare is not observed simultaneously by the EHT but is followed by a significant increase in millimeter flux variability immediately after the X-ray outburst, indicating a likely connection in the emission physics near the event horizon. We compare Sgr A*'s broadband flux during the EHT campaign to its historical spectral energy distribution and find that both the quiescent emission and flare emission are consistent with its long-term behavior.
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9.
  • Botvinik-Nezer, Rotem, et al. (författare)
  • Variability in the analysis of a single neuroimaging dataset by many teams
  • 2020
  • Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 582, s. 84-88
  • Tidskriftsartikel (refereegranskat)abstract
    • Data analysis workflows in many scientific domains have become increasingly complex and flexible. Here we assess the effect of this flexibility on the results of functional magnetic resonance imaging by asking 70 independent teams to analyse the same dataset, testing the same 9 ex-ante hypotheses(1). The flexibility of analytical approaches is exemplified by the fact that no two teams chose identical workflows to analyse the data. This flexibility resulted in sizeable variation in the results of hypothesis tests, even for teams whose statistical maps were highly correlated at intermediate stages of the analysis pipeline. Variation in reported results was related to several aspects of analysis methodology. Notably, a meta-analytical approach that aggregated information across teams yielded a significant consensus in activated regions. Furthermore, prediction markets of researchers in the field revealed an overestimation of the likelihood of significant findings, even by researchers with direct knowledge of the dataset(2-5). Our findings show that analytical flexibility can have substantial effects on scientific conclusions, and identify factors that may be related to variability in the analysis of functional magnetic resonance imaging. The results emphasize the importance of validating and sharing complex analysis workflows, and demonstrate the need for performing and reporting multiple analyses of the same data. Potential approaches that could be used to mitigate issues related to analytical variability are discussed. The results obtained by seventy different teams analysing the same functional magnetic resonance imaging dataset show substantial variation, highlighting the influence of analytical choices and the importance of sharing workflows publicly and performing multiple analyses.
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12.
  • Dima, Danai, et al. (författare)
  • Subcortical volumes across the lifespan : Data from 18,605 healthy individuals aged 3-90 years.
  • 2022
  • Ingår i: Human Brain Mapping. - : Wiley. - 1065-9471 .- 1097-0193. ; 43:1, s. 452-469
  • Tidskriftsartikel (refereegranskat)abstract
    • Age has a major effect on brain volume. However, the normative studies available are constrained by small sample sizes, restricted age coverage and significant methodological variability. These limitations introduce inconsistencies and may obscure or distort the lifespan trajectories of brain morphometry. In response, we capitalized on the resources of the Enhancing Neuroimaging Genetics through Meta-Analysis (ENIGMA) Consortium to examine age-related trajectories inferred from cross-sectional measures of the ventricles, the basal ganglia (caudate, putamen, pallidum, and nucleus accumbens), the thalamus, hippocampus and amygdala using magnetic resonance imaging data obtained from 18,605 individuals aged 3-90 years. All subcortical structure volumes were at their maximum value early in life. The volume of the basal ganglia showed a monotonic negative association with age thereafter; there was no significant association between age and the volumes of the thalamus, amygdala and the hippocampus (with some degree of decline in thalamus) until the sixth decade of life after which they also showed a steep negative association with age. The lateral ventricles showed continuous enlargement throughout the lifespan. Age was positively associated with inter-individual variability in the hippocampus and amygdala and the lateral ventricles. These results were robust to potential confounders and could be used to examine the functional significance of deviations from typical age-related morphometric patterns.
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13.
  • Frangou, Sophia, et al. (författare)
  • Cortical thickness across the lifespan : Data from 17,075 healthy individuals aged 3-90 years
  • 2022
  • Ingår i: Human Brain Mapping. - : John Wiley & Sons. - 1065-9471 .- 1097-0193. ; 43:1, s. 431-451
  • Tidskriftsartikel (refereegranskat)abstract
    • Delineating the association of age and cortical thickness in healthy individuals is critical given the association of cortical thickness with cognition and behavior. Previous research has shown that robust estimates of the association between age and brain morphometry require large-scale studies. In response, we used cross-sectional data from 17,075 individuals aged 3-90 years from the Enhancing Neuroimaging Genetics through Meta-Analysis (ENIGMA) Consortium to infer age-related changes in cortical thickness. We used fractional polynomial (FP) regression to quantify the association between age and cortical thickness, and we computed normalized growth centiles using the parametric Lambda, Mu, and Sigma method. Interindividual variability was estimated using meta-analysis and one-way analysis of variance. For most regions, their highest cortical thickness value was observed in childhood. Age and cortical thickness showed a negative association; the slope was steeper up to the third decade of life and more gradual thereafter; notable exceptions to this general pattern were entorhinal, temporopolar, and anterior cingulate cortices. Interindividual variability was largest in temporal and frontal regions across the lifespan. Age and its FP combinations explained up to 59% variance in cortical thickness. These results may form the basis of further investigation on normative deviation in cortical thickness and its significance for behavioral and cognitive outcomes.
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14.
  • Sikkema, Lisa, et al. (författare)
  • An integrated cell atlas of the lung in health and disease
  • 2023
  • Ingår i: Nature Medicine. - : Springer Nature. - 1078-8956 .- 1546-170X. ; 29:6, s. 1563-1577
  • Tidskriftsartikel (refereegranskat)abstract
    • Single-cell technologies have transformed our understanding of human tissues. Yet, studies typically capture only a limited number of donors and disagree on cell type definitions. Integrating many single-cell datasets can address these limitations of individual studies and capture the variability present in the population. Here we present the integrated Human Lung Cell Atlas (HLCA), combining 49 datasets of the human respiratory system into a single atlas spanning over 2.4 million cells from 486 individuals. The HLCA presents a consensus cell type re-annotation with matching marker genes, including annotations of rare and previously undescribed cell types. Leveraging the number and diversity of individuals in the HLCA, we identify gene modules that are associated with demographic covariates such as age, sex and body mass index, as well as gene modules changing expression along the proximal-to-distal axis of the bronchial tree. Mapping new data to the HLCA enables rapid data annotation and interpretation. Using the HLCA as a reference for the study of disease, we identify shared cell states across multiple lung diseases, including SPP1 + profibrotic monocyte-derived macrophages in COVID-19, pulmonary fibrosis and lung carcinoma. Overall, the HLCA serves as an example for the development and use of large-scale, cross-dataset organ atlases within the Human Cell Atlas.
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15.
  • Villa, Luisa L., et al. (författare)
  • Quadrivalent vaccine against human papillomavirus to prevent high-grade cervical lesions
  • 2007
  • Ingår i: New England Journal of Medicine. - 0028-4793 .- 1533-4406. ; 356:19, s. 1915-1927
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: Human papillomavirus types 16 (HPV-16) and 18 (HPV-18) cause approximately 70% of cervical cancers worldwide. A phase 3 trial was conducted to evaluate a quadrivalent vaccine against HPV types 6, 11, 16, and 18 (HPV-6/11/16/18) for the prevention of high-grade cervical lesions associated with HPV-16 and HPV-18. METHODS: In this randomized, double-blind trial, we assigned 12,167 women between the ages of 15 and 26 years to receive three doses of either HPV-6/11/16/18 vaccine or placebo, administered at day 1, month 2, and month 6. The primary analysis was performed for a per-protocol susceptible population that included 5305 women in the vaccine group and 5260 in the placebo group who had no virologic evidence of infection with HPV-16 or HPV-18 through 1 month after the third dose (month 7). The primary composite end point was cervical intraepithelial neoplasia grade 2 or 3, adenocarcinoma in situ, or cervical cancer related to HPV-16 or HPV-18. RESULTS: Subjects were followed for an average of 3 years after receiving the first dose of vaccine or placebo. Vaccine efficacy for the prevention of the primary composite end point was 98% (95.89% confidence interval [CI], 86 to 100) in the per-protocol susceptible population and 44% (95% CI, 26 to 58) in an intention-to-treat population of all women who had undergone randomization (those with or without previous infection). The estimated vaccine efficacy against all high-grade cervical lesions, regardless of causal HPV type, in this intention-to-treat population was 17% (95% CI, 1 to 31). CONCLUSIONS: In young women who had not been previously infected with HPV-16 or HPV-18, those in the vaccine group had a significantly lower occurrence of high-grade cervical intraepithelial neoplasia related to HPV-16 or HPV-18 than did those in the placebo group.
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16.
  • Abraham, Roshan Mammen, et al. (författare)
  • Tau neutrinos in the next decade : from GeV to EeV
  • 2022
  • Ingår i: Journal of Physics G. - : Institute of Physics Publishing (IOPP). - 0954-3899 .- 1361-6471. ; 49:11
  • Tidskriftsartikel (refereegranskat)abstract
    • Tau neutrinos are the least studied particle in the standard model. This whitepaper discusses the current and expected upcoming status of tau neutrino physics with attention to the broad experimental and theoretical landscape spanning long-baseline, beam-dump, collider, and astrophysical experiments. This whitepaper was prepared as a part of the NuTau2021 Workshop.
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17.
  • Barker, A., et al. (författare)
  • Age-dependent decline of beta-cell function in type 1 diabetes after diagnosis: a multi-centre longitudinal study
  • 2014
  • Ingår i: Diabetes, obesity and metabolism. - : Wiley. - 1462-8902 .- 1463-1326. ; 16:3, s. 262-267
  • Tidskriftsartikel (refereegranskat)abstract
    • AimsC-peptide secretion is currently the only available clinical biomarker to measure residual -cell function in type 1 diabetes. However, the natural history of C-peptide decline after diagnosis can vary considerably dependent upon several variables. We investigated the shape of C-peptide decline over time from type 1 diabetes onset in relation to age at diagnosis, haemoglobin A1c (HbA1c) levels and insulin dose. MethodsWe analysed data from 3929 type 1 diabetes patients recruited from seven European centres representing all age groups at disease onset (childhood, adolescence and adulthood). The influence of the age at onset on -cell function was investigated in a longitudinal analysis at diagnosis and up to 5-years follow-up. ResultsFasting C-peptide (FCP) data at diagnosis were available in 3668 patients stratified according to age at diagnosis in four groups (less than5years, n=344; greater than5yearsless than10years, n=668; greater than10yearsless than18years, n=991; greater than18years, n=1655). FCP levels were positively correlated with age (pless than0.001); the subsequent decline in FCP over time was log-linear with a greater decline rate in younger age groups (pless than0.0001). ConclusionsThis study reveals a positive correlation between age at diagnosis of type 1 diabetes and FCP with a more rapid decline of -cell function in the very young patients. These data can inform the design of clinical trials using C-peptide values as an end-point for the effect of a given treatment.
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18.
  • Bauer, Michael, et al. (författare)
  • Association between solar insolation and a history of suicide attempts in bipolar I disorder.
  • 2019
  • Ingår i: Journal of psychiatric research. - : Elsevier BV. - 1879-1379 .- 0022-3956. ; 113, s. 1-9
  • Tidskriftsartikel (refereegranskat)abstract
    • In many international studies, rates of completed suicide and suicide attempts have a seasonal pattern that peaks in spring or summer. This exploratory study investigated the association between solar insolation and a history of suicide attempt in patients with bipolar I disorder. Solar insolation is the amount of electromagnetic energy from the Sun striking a surface area on Earth. Data were collected previously from 5536 patients with bipolar I disorder at 50 collection sites in 32 countries at a wide range of latitudes in both hemispheres. Suicide related data were available for 3365 patients from 310 onset locations in 51 countries. 1047 (31.1%) had a history of suicide attempt. There was a significant inverse association between a history of suicide attempt and the ratio of mean winter solar insolation/mean summer solar insolation. This ratio is smallest near the poles where the winter insolation is very small compared to the summer insolation. This ratio is largest near the equator where there is relatively little variation in the insolation over the year. Other variables in the model that were positively associated with suicide attempt were being female, a history of alcohol or substance abuse, and being in a younger birth cohort. Living in a country with a state-sponsored religion decreased the association. (All estimated coefficients p<0.01). In summary, living in locations with large changes in solar insolation between winter and summer may be associated with increased suicide attempts in patients with bipolar disorder. Further investigation of the impacts of solar insolation on the course of bipolar disorder is needed.
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19.
  • Lauria, A., et al. (författare)
  • BMI is an important driver of beta-cell loss in type 1 diabetes upon diagnosis in 10 to 18-year-old children
  • 2015
  • Ingår i: European Journal of Endocrinology. - : BioScientifica. - 0804-4643 .- 1479-683X. ; 172:2, s. 107-113
  • Tidskriftsartikel (refereegranskat)abstract
    • Objective: Body weight-related insulin resistance probably plays a role in progression to type 1 diabetes, but has an uncertain impact following diagnosis. In this study, we investigated whether BMI measured at diagnosis was an independent predictor of C-peptide decline 1-year post-diagnosis. Design: Multicentre longitudinal study carried out at diagnosis and up to 1-year follow-up. Methods: Data on C-peptide were collected from seven diabetes centres in Europe. Patients were grouped according to age at diagnosis (less than5 years, n = 126; greater than5 years less than10 years, n = 295; greater than10 years less than18 years, n = 421; greater than18 years, n = 410). Linear regression was used to investigate whether BMI was an independent predictor of change in fasting C-peptide over 1 year. Models were additionally adjusted for baseline insulin dose and HbA1c. Results: In individuals diagnosed between 0 and 5 years, 5 and 10 years and those diagnosed greater than18 years, we found no association between BMI and C-peptide decline. In patients aged 10-18 years, higher BMI at baseline was associated with a greater decline in fasting C-peptide over 1 year with a decrease (beta 95% CI; P value) of 0.025 (0.010, 0.041) nM/kg per m(2) higher baseline BMI (P = 0.001). This association remained significant after adjusting for gender and differences in HbA1c and insulin dose (beta = 0.026, 95% CI = 0.0097, 0.042; P = 0.002). Conclusions: These observations indicate that increased body weight and increased insulin demand are associated with more rapid disease progression after diagnosis of type 1 diabetes in an age group 10-18 years. This should be considered in studies of beta-cell function in type 1 diabetes.
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21.
  • Petrov, Dmitry, et al. (författare)
  • Machine Learning for Large-Scale Quality Control of 3D Shape Models in Neuroimaging
  • 2017
  • Ingår i: Machine learning in medical imaging. MLMI (Workshop). - Cham : Springer International Publishing. ; 10541, s. 371-378
  • Tidskriftsartikel (refereegranskat)abstract
    • As very large studies of complex neuroimaging phenotypes become more common, human quality assessment of MRI-derived data remains one of the last major bottlenecks. Few attempts have so far been made to address this issue with machine learning. In this work, we optimize predictive models of quality for meshes representing deep brain structure shapes. We use standard vertex-wise and global shape features computed homologously across 19 cohorts and over 7500 human-rated subjects, training kernelized Support Vector Machine and Gradient Boosted Decision Trees classifiers to detect meshes of failing quality. Our models generalize across datasets and diseases, reducing human workload by 30-70%, or equivalently hundreds of human rater hours for datasets of comparable size, with recall rates approaching inter-rater reliability.
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22.
  • Razavi, Homie A., et al. (författare)
  • Hepatitis D double reflex testing of all hepatitis B carriers in low-HBV- and high-HBV/HDV-prevalence countries
  • 2023
  • Ingår i: JOURNAL OF HEPATOLOGY. - : Elsevier. - 0168-8278 .- 1600-0641. ; 79:2, s. 576-580
  • Tidskriftsartikel (refereegranskat)abstract
    • Hepatitis D virus (HDV) infection occurs as a coinfection with hepatitis B and increases the risk of hepatocellular carcinoma, decompensated cirrhosis, and mortality compared to hepatitis B virus (HBV) monoinfection. Reliable estimates of the prevalence of HDV infection and disease burden are essential to formulate strategies to find coinfected individuals more effectively and efficiently. The global prevalence of HBV infections was estimated to be 262,240,000 in 2021. Only 1,994,000 of the HBV in-fections were newly diagnosed in 2021, with more than half of the new diagnoses made in China. Our initial estimates indicated a much lower prevalence of HDV antibody (anti-HDV) and HDV RNA positivity than previously reported in published studies. Ac-curate estimates of HDV prevalence are needed. The most effective method to generate estimates of the prevalence of anti-HDV and HDV RNA positivity and to find undiagnosed individuals at the national level is to implement double reflex testing. This re-quires anti-HDV testing of all hepatitis B surface antigen-positive individuals and HDV RNA testing of all anti-HDV-positive in-dividuals. This strategy is manageable for healthcare systems since the number of newly diagnosed HBV cases is low. At the global level, a comprehensive HDV screening strategy would require only 1,994,000 HDV antibody tests and less than 89,000 HDV PCR tests. Double reflex testing is the preferred strategy in countries with a low prevalence of HBV and those with a high prevalence of both HBV and HDV. For example, in the European Union and North America only 35,000 and 22,000 cases, respectively, will require anti-HDV testing annually.
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23.
  • Razavi-Shearer, Devin M., et al. (författare)
  • Adjusted estimate of the prevalence of hepatitis delta virus in 25 countries and territories
  • 2024
  • Ingår i: JOURNAL OF HEPATOLOGY. - 0168-8278 .- 1600-0641. ; 80:2, s. 232-242
  • Tidskriftsartikel (refereegranskat)abstract
    • Background & Aims: Hepatitis delta virus (HDV) is a satellite RNA virus that requires the hepatitis B virus (HBV) for assembly and propagation. Individuals infected with HDV progress to advanced liver disease faster than HBV-monoinfected individuals. Recent studies have estimated the global prevalence of anti-HDV antibodies among the HBV-infected population to be 5-15%. This study aimed to better understand HDV prevalence at the population level in 25 countries/territories. Methods: We conducted a literature review to determine the prevalence of anti-HDV and HDV RNA in hepatitis B surface antigen (HBsAg)-positive individuals in 25 countries/territories. Virtual meetings were held with experts from each setting to discuss the findings and collect unpublished data. Data were weighted for patient segments and regional heterogeneity to estimate the prevalence in the HBV-infected population. The findings were then combined with The Polaris Observatory HBV data to estimate the anti-HDV and HDV RNA prevalence in each country/territory at the population level. Results: After adjusting for geographical distribution, disease stage and special populations, the anti-HDV prevalence among the HBsAg+ population changed from the literature estimate in 19 countries. The highest anti-HDV prevalence was 60.1% in Mongolia. Once adjusted for the size of the HBsAg+ population and HDV RNA positivity rate, China had the highest absolute number of HDV RNA+ cases. Conclusions: We found substantially lower HDV prevalence than previously reported, as prior meta-analyses primarily focused on studies conducted in groups/regions that have a higher probability of HBV infection: tertiary care centers, specific risk groups or geographical regions. There is large uncertainty in HDV prevalence estimates. The implementation of reflex testing would improve estimates, while also allowing earlier linkage to care for HDV RNA+ individuals. The logistical and economic burden of reflex testing on the health system would be limited, as only HBsAg+ cases would be screened.
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24.
  • Adams, David, et al. (författare)
  • Long-term safety and efficacy of patisiran for hereditary transthyretin-mediated amyloidosis with polyneuropathy : 12-month results of an open-label extension study
  • 2021
  • Ingår i: Lancet Neurology. - : Elsevier. - 1474-4422 .- 1474-4465. ; 20:1, s. 49-59
  • Tidskriftsartikel (refereegranskat)abstract
    • Background Hereditary transthyretin-mediated amyloidosis is a rare, inherited, progressive disease caused by mutations in the transthyretin (TTR) gene. We assessed the safety and efficacy of long-term treatment with patisiran, an RNA interference therapeutic that inhibits TTR production, in patients with hereditary transthyretin-mediated amyloidosis with polyneuropathy. Methods This multicentre, open-label extension (OLE) trial enrolled patients at 43 hospitals or clinical centres in 19 countries as of Sept 24, 2018. Patients were eligible if they had completed the phase 3 APOLLO or phase 2 OLE parent studies and tolerated the study drug. Eligible patients from APOLLO (patisiran and placebo groups) and the phase 2 OLE (patisiran group) studies enrolled in this global OLE trial and received patisiran 0.3 mg/kg by intravenous infusion every 3 weeks with plans to continue to do so for up to 5 years. Efficacy assessments included measures of polyneuropathy (modified Neuropathy Impairment Score +7 [mNIS+7]), quality of life, autonomic symptoms, nutritional status, disability, ambulation status, motor function, and cardiac stress, with analysis by study groups (APOLLO-placebo, APOLLO-patisiran, phase 2 OLE patisiran) based on allocation in the parent trial. The global OLE is ongoing with no new enrolment, and current findings are based on the interim analysis of the patients who had completed 12-month efficacy assessments as of the data cutoff. Safety analyses included all patients who received one or more dose of patisiran up to the data cutoff. This study is registered with ClinicalTrials.gov, NCT02510261. Findings Between July 13, 2015, and Aug 21, 2017, of 212 eligible patients, 211 were enrolled: 137 patients from the APOLLO-patisiran group, 49 from the APOLLO-placebo group, and 25 from the phase 2 OLE patisiran group. At the data cutoff on Sept 24, 2018, 126 (92%) of 137 patients from the APOLLO-patisiran group, 38 (78%) of 49 from the APOLLO-placebo group, and 25 (100%) of 25 from the phase 2 OLE patisiran group had completed 12-month assessments. At 12 months, improvements in mNIS+7 with patisiran were sustained from parent study baseline with treatment in the global OLE (APOLLO-patisiran mean change -4.0, 95 % CI -7.7 to -0.3; phase 2 OLE patisiran -4.7, -11.9 to 2.4). Mean mNIS+7 score improved from global OLE enrolment in the APOLLO-placebo group (mean change from global OLE enrolment -1.4, 95% CI -6.2 to 3.5). Overall, 204 (97%) of 211 patients reported adverse events, 82 (39%) reported serious adverse events, and there were 23 (11%) deaths. Serious adverse events were more frequent in the APOLLO-placebo group (28 [57%] of 49) than in the APOLLO-patisiran (48 [35%] of 137) or phase 2 OLE patisiran (six [24%] of 25) groups. The most common treatment-related adverse event was mild or moderate infusion-related reactions. The frequency of deaths in the global OLE was higher in the APOLLO-placebo group (13 [27%] of 49), who had a higher disease burden than the APOLLO-patisiran (ten [7%] of 137) and phase 2 OLE patisiran (0 of 25) groups. Interpretation In this interim 12-month analysis of the ongoing global OLE study, patisiran appeared to maintain efficacy with an acceptable safety profile in patients with hereditary transthyretin-mediated amyloidosis with polyneuropathy. Continued long-term follow-up will be important for the overall assessment of safety and efficacy with patisiran. Copyright (C) 2020 Elsevier Ltd. All rights reserved.
  •  
25.
  • Álvarez-Muñiz, Jaime, et al. (författare)
  • The Giant Radio Array for Neutrino Detection (GRAND) : Science and design
  • 2020
  • Ingår i: Science China Physics, Mechanics & Astronomy. - : Springer Science and Business Media LLC. - 1674-7348 .- 1869-1927. ; 63:1
  • Forskningsöversikt (refereegranskat)abstract
    • The Giant Radio Array for Neutrino Detection (GRAND) is a planned large-scale observatory of ultra-high-energy (UHE) cosmic particles, with energies exceeding 108 GeV. Its goal is to solve the long-standing mystery of the origin of UHE cosmic rays. To do this, GRAND will detect an unprecedented number of UHE cosmic rays and search for the undiscovered UHE neutrinos and gamma rays associated to them with unmatched sensitivity. GRAND will use large arrays of antennas to detect the radio emission coming from extensive air showers initiated by UHE particles in the atmosphere. Its design is modular: 20 separate, independent sub-arrays, each of 10000 radio antennas deployed over 10000 km(2). A staged construction plan will validate key detection techniques while achieving important science goals early. Here we present the science goals, detection strategy, preliminary design, performance goals, and construction plans for GRAND.
  •  
26.
  • Arayeshnia, Amir, et al. (författare)
  • Miniaturized CPW-fed bowtie slot antenna for wearable biomedical applications
  • 2020
  • Ingår i: 2020 14th European Conference on Antennas and Propagation (EuCAP). - 9788831299008
  • Konferensbidrag (refereegranskat)abstract
    • A miniaturized, low -profile, flexible, and wearable ultra-wideband antenna for biomedical applications is proposed. The antenna is designed to operate in wearable conditions with the presence of multilayer biological tissues. A meandering technique is employed to reduce the electrical size of the antenna. The operational band of the proposed antenna is 0.5-4.5 GHz, while its dimensions are as small as 21x19.25x0.025 mm3. The antenna is simulated using a commercial full-wave simulator (CST Microwave Studio), fabricated on Polyethylene terephthalate (PET), and tested in realistic scenarios. The simulation and measurement results are in good compliance with each other.
  •  
27.
  • Asan, Noor Badariah, 1984-, et al. (författare)
  • Effect of Thickness Inhomogeneity in Fat Tissue on In-Body Microwave Propagation
  • 2018
  • Ingår i: Proceedings of the 2018 IEEE/MTT-S International Microwave Biomedical Conference (IMBIOC). - Philadelphia, USA : IEEE. - 9781538659182 ; , s. 136-138
  • Konferensbidrag (refereegranskat)abstract
    • In recent studies, it has been found that fat tissue can be used as a microwave communication channel. In this article, the effect of thickness inhomogeneities in fat tissues on the performance of in-body microwave communication at 2.45 GHz is investigated using phantom models. We considered two models namely concave and convex geometrical fat distribution to account for the thickness inhomogeneities. The thickness of the fat tissue is varied from 5 mm to 45 mm and the Gap between the transmitter/receiver and the starting and ending of concavity/convexity is varied from 0 mm to 25 mm for a length of 100 mm to study the behavior in the microwave propagation. The phantoms of different geometries, concave and convex, are used in this work to validate the numerical studies. It was noticed that the convex model exhibited higher signal coupling by an amount of 1 dB (simulation) and 2 dB (measurement) compared to the concave model. From the study, it was observed that the signal transmission improves up to 30 mm thick fat and reaches a plateau when the thickness is increased further.
  •  
28.
  • Asan, Noor Badariah, 1984-, et al. (författare)
  • Effects of Blood Vessels on Fat Channel Microwave Communication
  • 2018
  • Ingår i: 2018 IEEE Conference on Antenna Measurements &amp; Applications (CAMA). - : IEEE. - 9781538657959
  • Konferensbidrag (refereegranskat)abstract
    • This study aims to investigate the reliability of intra-body microwave propagation through the fat tissue in presence of blood vessels. Here, we consider three types of blood vessels with different sizes. We investigate the impact of the number of blood vessels and their alignment on the transmission of microwave signals through the fat channel. In our study, we employ two probes that act as a transmitter and a receiver. The probes are designed to operate at the Industrial, Scientific, and Medical radio band (2.45 GHz). For a channel length of 100 mm, our results indicate that the presence of the blood vessels may increase the channel path loss by similar to 1.5 dB and similar to 4.5 dB when the vessels are aligned and orthogonally aligned with the fat channel, respectively.
  •  
29.
  • Asan, Noor Badariah, 1984-, et al. (författare)
  • Fat-IntraBody Communication at 5.8 GHz : Verification of Dynamic Body Movement Effects using Computer Simulation and Experiments
  • 2021
  • Ingår i: IEEE Access. - : IEEE. - 2169-3536. ; 9, s. 48429-48445
  • Tidskriftsartikel (refereegranskat)abstract
    • This paper presents numerical modeling and experimental validation of the signal path loss at the 5.8 GHz Industrial, Scientific, and Medical (ISM) band, performed in the context of fat-intrabody communication (fat-IBC), a novel intrabody communication platform using the body-omnipresent fat tissue as the key wave-guiding medium. Such work extends our previous works at 2.0 and 2.4 GHz in the characterization of its performance in other useful frequency range. In addition, this paper also includes studies of both static and dynamic human body movements. In order to provide with a more comprehensive characterization of the communication performance at this frequency, this work focuses on investigating the path loss at different configurations of fat tissue thickness, antenna polarizations, and locations in the fat channel. We bring more realism to the experimental validation by using excised tissues from porcine cadaver as both their fat and muscle tissues have electromagnetic characteristics similar to those of human with respect to current state-of-art artificial phantom models. Moreover, for favorable signal excitation and reception in the fat-IBC model, we used topology optimized waveguide probes. These probes provide an almost flat response in the frequency range from 3.2 to 7.1 GHz which is higher than previous probes and improve the evaluation of the performance of the fat-IBC model. We also discuss various aspects of real-world scenarios by examining different models, particularly homogeneous multilayered skin, fat, and muscle tissue. To study the effect of dynamic body movements, we examine the impact of misalignment, both in space and in wave polarization, between implanted nodes. We show in particular that the use of fat-IBC techniques can be extended up in frequency to a broadband channel at 5.8 GHz.
  •  
30.
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31.
  • Brown, Darron R., et al. (författare)
  • The Impact of Quadrivalent Human Papillomavirus (HPV; Types 6, 11, 16, and 18) L1 Virus-Like Particle Vaccine on Infection and Disease Due to Oncogenic Nonvaccine HPV Types in Generally HPV-Naive Women Aged 16-26 Years
  • 2009
  • Ingår i: Journal Of Infectious Diseases. - : Oxford University Press (OUP). - 0022-1899 .- 1537-6613. ; 199:7, s. 926-935
  • Konferensbidrag (refereegranskat)abstract
    • Background. Human papillomavirus (HPV)-6/11/16/18 vaccine reduces the risk of HPV-6/11/16/18-related cervical intraepithelial neoplasia (CIN) 1-3 or adenocarcinoma in situ (AIS). Here, its impact on CIN1-3/AIS associated with nonvaccine oncogenic HPV types was evaluated. Methods. We enrolled 17,622 women aged 16-26 years. All underwent cervicovaginal sampling and Pap testing at regular intervals for up to 4 years. HPV genotying was performed for biopsy samples, and histological diagnoses were determined by a pathology panel. Analyses were conducted among subjects who were negative for 14 HPV types on day 1. Prespecified analyses included infection of >= 6 months' duration and CIN1-3/AIS due to the 2 and 5 most common HPV types in cervical cancer after HPV types 16 and 18, as well as all tested nonvaccine types. Results. Vaccination reduced the incidence of HPV-31/45 infection by 40.3% (95% confidence interval [CI], 13.9% to 59.0%) and of CIN1-3/AIS by 43.6% (95% CI, 12.9% to 64.1%), respectively. The reduction in HPV-31/33/45/52/58 infection and CIN1-3/AIS was 25.0% (95% CI, 5.0% to 40.9%) and 29.2% (95% CI, 8.3% to 45.5%), respectively. Efficacy for CIN2-3/AIS associated with the 10 nonvaccine HPV types was 32.5% (95% CI, 6.0% to 51.9%). Reductions were most notable for HPV-31. Conclusions. HPV-6/11/16/18 vaccine reduced the risk of CIN2-3/AIS associated with nonvaccine types responsible for similar to 20% of cervical cancers. The clinical benefit of cross-protection is not expected to be fully additive to the efficacy already observed against HPV-6/11/16/18-related disease, because women may have >1 CIN lesion, each associated with a different HPV type.
  •  
32.
  • Calzone, Rocco, et al. (författare)
  • Innovations in Biomedicine : Measuring Physiological Parameters Becomes As Simple As Applying A Plaster on the Body
  • 2019
  • Ingår i: Proceedings Of The 2019 International Conference On Electromagnetics In Advanced Applications (ICEAA). - New York : IEEE. - 9781728105635 ; , s. 1443-1446
  • Konferensbidrag (refereegranskat)abstract
    • Electromagnetic applications play an essential role in medical research. As a response to the consistent increase in the number of people suffering from various diseases, the medical research is always looking for better diagnostic tools, expedited information transfer technologies, accurate prognosis devices, efficient patient management system and other alternative medicine strategies. In this context, the H2020 Project SINTEC proposes a soft intelligent epidermal communication platform where two main innovations are integrated: soft epidermal electronics and the intra-body communication based on fat tissue as a transmission channel. This proposed platform will host miniaturized, conformal and flexible sensing and data transfer technologies to enable real-time monitoring of certain vital parameters at any time (while doing sport, sleeping or watching television without having to go to a health specialized facility and/or using different devices such as a pulse oximetry, heart rate monitor and thermometer). As part of the phantom development, empirical models relating bioimpedance signals to other physiological signals (ECG, Sp02, Blood Pressure, etc.) is being studied and will be used to optimize phantom -based demonstrators as close as possible to human subjects. To this end, proper characterization of bioimpedance signals in different human subjects is crucial to devise such empirical models. This work presents preliminary results in four human volunteers, with different weight, gender and age, using two types of electrodes configurations. These results show that bioimpedance signals correlate well with volunteer's metadata as predicted by previous works. Finally, the communication through the FAT-channel and also comparisons with the traditional Freespace BLE (Bluetooth Low Energy) protocol will be demonstrated.
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33.
  • Dematties, Dario, et al. (författare)
  • A Computational Theory for the Emergence of Grammatical Categories in Cortical Dynamics
  • 2020
  • Ingår i: Frontiers in Neural Circuits. - : FRONTIERS MEDIA SA. - 1662-5110. ; 14
  • Tidskriftsartikel (refereegranskat)abstract
    • A general agreement in psycholinguistics claims that syntax and meaning are unified precisely and very quickly during online sentence processing. Although several theories have advanced arguments regarding the neurocomputational bases of this phenomenon, we argue that these theories could potentially benefit by including neurophysiological data concerning cortical dynamics constraints in brain tissue. In addition, some theories promote the integration of complex optimization methods in neural tissue. In this paper we attempt to fill these gaps introducing a computational model inspired in the dynamics of cortical tissue. In our modeling approach, proximal afferent dendrites produce stochastic cellular activations, while distal dendritic branches-on the other hand-contribute independently to somatic depolarization by means of dendritic spikes, and finally, prediction failures produce massive firing events preventing formation of sparse distributed representations. The model presented in this paper combines semantic and coarse-grained syntactic constraints for each word in a sentence context until grammatically related word function discrimination emerges spontaneously by the sole correlation of lexical information from different sources without applying complex optimization methods. By means of support vector machine techniques, we show that the sparse activation features returned by our approach are well suited-bootstrapping from the features returned by Word Embedding mechanisms-to accomplish grammatical function classification of individual words in a sentence. In this way we develop a biologically guided computational explanation for linguistically relevant unification processes in cortex which connects psycholinguistics to neurobiological accounts of language. We also claim that the computational hypotheses established in this research could foster future work on biologically-inspired learning algorithms for natural language processing applications.
  •  
34.
  • Dematties, Dario, et al. (författare)
  • Deep Learning of Nanopore Sensing Signals Using a Bi-Path Network
  • 2021
  • Ingår i: ACS Nano. - : American Chemical Society (ACS). - 1936-0851 .- 1936-086X. ; 15:9, s. 14419-14429
  • Tidskriftsartikel (refereegranskat)abstract
    • Temporal changes in electrical resistance of a nanopore sensor caused by translocating target analytes are recorded as a sequence of pulses on current traces. Prevalent algorithms for feature extraction in pulse-like signals lack objectivity because empirical amplitude thresholds are user-defined to single out the pulses from the noisy background. Here, we use deep learning for feature extraction based on a bipath network (B-Net). After training, the B-Net acquires the prototypical pulses and the ability of both pulse recognition and feature extraction without a priori assigned parameters. The B-Net is evaluated on simulated data sets and further applied to experimental data of DNA and protein translocation. The B-Net results are characterized by small relative errors and stable trends. The B-Net is further shown capable of processing data with a signal-to-noise ratio equal to 1, an impossibility for threshold-based algorithms. The B-Net presents a generic architecture applicable to pulse-like signals beyond nanopore currents.
  •  
35.
  • Dorfman, Mauricio, et al. (författare)
  • Chronic-intermittent cold stress in rats induces selective ovarian insulin resistance.
  • 2009
  • Ingår i: Biology of reproduction. - : Oxford University Press (OUP). - 0006-3363 .- 1529-7268. ; 80:2, s. 264-71
  • Tidskriftsartikel (refereegranskat)abstract
    • In rat ovary chronic cold stress increases sympathetic nerve activity, modifies follicular development, and initiates a polycystic condition. To see whether there is a relationship between the previously described changes in follicular development and metabolic changes similar to those in women with polycystic ovary, we have studied the effect of chronic cold stress (4 degrees C for 3 h/day, Monday to Friday, for 4 wk) on insulin sensitivity and the effect of insulin on sympathetic ovarian activity. Although cold-stressed rats ate more than the controls, they did not gain more weight. Insulin sensitivity, determined by hyperinsulinemic-euglycemic clamp, was significantly increased in the stressed animals. Insulin in vitro increased the basal release of norepinephrine from the ovaries of control rats but not from those of stressed rats, suggesting a local neural resistance to insulin in stressed rats. The levels of mRNA and protein for IRS1 and SLC2A4 (also known as GLUT4), molecules involved in insulin signaling, decreased significantly in the ovaries but not in the muscle of stressed rats. This decrease was preferentially located in theca-interstitial cells compared with granulosa cells, indicating that theca cells (the only cells directly innervated by sympathetic nerves) are responsible for the ovarian insulin resistance found in stressed rats. These findings suggest that ovarian insulin resistance produced by chronic stress could be in part responsible for the development of the polycystic condition induced by stress.
  •  
36.
  • Ebrahimizadeh, Javad, et al. (författare)
  • Electromagnetic Time-Reversal Technique for Monitoring Skull Healing Stages
  • 2019
  • Ingår i: 2019 13th European Conference On Antennas And Propagation (EuCAP). - : IEEE. - 9788890701887
  • Konferensbidrag (refereegranskat)abstract
    • This paper provides a novel non-resonant spectroscopy technique for monitoring of the healing process in skull defects created in cranial surgery. Currently, there is not such a method and information on the healing process which is vital to avoid further complications and for a better understanding of the process. During the healing, which can take several months, the thickness and the permittivity of the skull varies. The proposed approach makes use of the approximated Dyadic Green's function integral equation for deriving the variations in permittivity of the skull. The scattered electric field from the defect is collected using Time-Reversal Array (TRA) in order to produce the Multi-StaticData Matrix (MDM). The singular value decomposition on the MDM matrix based on time reversal operator (TRO) decomposition (known under French acronym DORT), provides information of the permittivity of the defect. The problem of the sensing the defect response after the cranial surgery is formulated for multi-layer medium and it will be shown that the dominant singular values are corresponding to the permittivity of the defect. Finally, the veracity of the theory is clarified by conducting a numerical simulation for a planar multi-layer medium consisting of skin, skull brain and a defect embedded in the skull. We show that the dominant singular values corresponding to the defect permittivity vary significantly which conclude that the dominant singular value can be a good criterion for monitoring the skull healing stages.
  •  
37.
  • Ebrahimizadeh, Javad, et al. (författare)
  • Pathloss Calculation for Fat-Intra Body Communication Using Poynting Vector Theory
  • 2020
  • Ingår i: 2020 14th European Conference on Antennas and Propagation (EuCAP). - 9788831299008
  • Konferensbidrag (refereegranskat)abstract
    • Recently, Fat-based Intra-Body Communication (Fat-IBC) has been proposed and studied in terms of its reliability in simulation and laboratory settings. We, in this work, try to address another important aspect of communication, namely pathloss, in the context of fat-IBC. The present paper provides numerical and experimental modeling of pathloss through the fat layer using the Poynting Vector theory and the Multi-layer dielectric Green's function (MGF). To calculate the pathloss based on Poynting vector theory, the electromagnetic field distribution through the involved media should be known. The present paper exploits the EM fields using MGF theory or commercial software CST Microwave Studio 2019. Finally, experimental measurement is done on ex-vivo tissue made of porcine skin, fat and muscle at the frequency range of 5 GHz - 6 GHz. The average measured pathloss is around 5.5 dB/cm which has good compliance with the theoretical Poynting vector pathloss estimation.
  •  
38.
  • Ebrahimizadeh, Javad, et al. (författare)
  • Time Reversal Microwave Imaging of Realistic Numerical Head Phantom for Bone Flap Healing Follow-up
  • 2020
  • Ingår i: 2020 IEEE MTT-S International Microwave Biomedical Conference (IMBioC). - 9781728158662 - 9781728158679
  • Konferensbidrag (refereegranskat)abstract
    • This paper presents the feasibility of using a microwave imaging system for monitoring bone mineralization progress overtime after craniotomy surgery. Any variation in the composition of the bone flap can be monitored as a variation in the intensity of the image. A simulation is conducted on a head structure derived from a numerical head phantom based on anatomically realistic MRI-derived FDTD models using commercial CST 2019 software. For simulation, a defect is provided in the skull layer surrounded by a 9-elements antenna. Applying Space-Frequency Time Reversal (TR) method, the image of defect is constructed for different permittivity of the defect ranging from 16 to 36. Results show that the image intensity at the defect location will decrease as the permittivity of the defect decreases.
  •  
39.
  • Engstrand, Johan, et al. (författare)
  • End-to-End Transmission of Physiological Data from Implanted Devices to a Cloud-Enabled Aggregator Using Fat Intra-Body Communication in a Live Porcine Model
  • 2022
  • Ingår i: 2022 16TH EUROPEAN CONFERENCE ON ANTENNAS AND PROPAGATION (EUCAP). - : Institute of Electrical and Electronics Engineers (IEEE). - 9788831299046 - 9781665416047
  • Konferensbidrag (refereegranskat)abstract
    • This article presents, for the first time, the end-to-end transmission of physiological data from implanted antennas mimicking sensors to a cloud-enabled aggregator device using fat intra-body communication (fat-IBC). The experiment was performed on a live porcine model in full accordance with ethical standards. Measurement data from two different sensors were collected and sent through a fat-IBC network. The fat-IBC network consisted of three nodes, of which two used antennas implanted in the fat tissue of a live porcine model and one used an on-body antenna placed on the skin. The sensor data was forwarded via Bluetooth Low Energy to an Intel Health Application Platform device, which in turn forwarded the encrypted data to a web server. The experimental results demonstrate that the fat channel can be used in an end-to-end communication scheme, which could involve relaying of sensor data from an implanted device to an external web server.
  •  
40.
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41.
  • Gaffoglio, Rossella, et al. (författare)
  • Compact Optimized Antenna Solution for Radiation Coupling Improvement in the Subcutaneous Fat Layer
  • 2023
  • Ingår i: 2023 17th European Conference on Antennas and Propagation, EuCAP. - : IEEE. - 9788831299077 - 9781665475419
  • Konferensbidrag (refereegranskat)abstract
    • Fat intra-body communication (Fat-IBC) aims at confining microwave propagation to the subcutaneous adipose tissue layer for the creation of a safe high-speed, high-bandwidth data transmission link through the body. This technique can be exploited to connect implantable medical devices and to implement a two-way transmission of recorded neural data and sensory stimulation signals between brain and robotic limbs. In this paper, a compact printed antenna solution for non-invasive tests of the Fat-IBC on non-human primates (NHPs) is proposed. This antenna is a printed monopole with a triangular radiating element embedded into a rigid brick, properly optimized to favor the radiation coupling in a 5mm-thick fat layer and minimize the signal propagation through the air. A promising wave coupling in the adipose tissue is achieved and a compact realizable layout is finalized for future prototyping and testing.
  •  
42.
  • Giannetta, H. M. R., et al. (författare)
  • Study of the electrical parameters drift due to mechanical stress in coupled conductors path on flexible polymeric substrate
  • 2022
  • Ingår i: 2022 Argentine Conference on Electronics (CAE). - : Institute of Electrical and Electronics Engineers (IEEE). - 9781728173351 - 9781728192659 ; , s. 37-40
  • Konferensbidrag (refereegranskat)abstract
    • In this work, the behavior of the drift in electrical impedance values of a coupled device constituting a flat rectangular inductor surrounded by a coupled antenna while subjected to mechanical stresses of over 10,000 bending-stretching cycles has been studied. It has shown correlation with mechanical aging and also is influenced by temperature variations on the device surface. The impact of the mechanical stress was studied separately for the bending-stretching and relaxation phases, considering in both cases the effect of temperature changes and mechanical stress, in order to obtain an adjustment equation for the measured experimental data.. From the fit, it was observed that when using an exponential function for the drift effect due to mechanical stress, the experimental curve was fitted with R-2=0.91 for the bending-stretching phase and R-2=0.79 for the relaxation phase.
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43.
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44.
  • Gutierrez, Mauricio, et al. (författare)
  • Forced response analysis of a transonic turbine using a free interface component mode synthesis method
  • 2015
  • Ingår i: 11th European Conference on Turbomachinery Fluid Dynamics and Thermodynamics, ETC 2015. - : European Conference on Turbomachinery (ETC).
  • Konferensbidrag (refereegranskat)abstract
    • Assessing forced response is crucial during the design phase of turbomachines. Since the analyses are computationally expensive and time-consuming when using full models, Reduced Order Models (ROM) are utilized to decrease the number of Degrees Of Freedom (DOF) and consequently analysis time and cost. The ROM used in the current analysis belongs to the component mode synthesis (CMS) method with a free-interface approach known as Craig-Chang. A transonic high pressure turbine is investigated featuring large ranges of disk and blade dominated modes depending in the Nodal Diameter (ND). The free-interface approach will be assessed in the disk and blade dominated regions with a detailed study of the frequencies and mode shapes. In addition, a forced response analysis within the blade dominated region is evaluated in the paper. Moreover, a study of the amount of modes required in the basis for the reduced order transformation matrix is presented.
  •  
45.
  • Gutierrez Salas, Mauricio, et al. (författare)
  • Forced response analysis of a mistuned compressor blisk comparing three different reduced order model approaches
  • 2016
  • Ingår i: Proceedings of the ASME Turbo Expo. - : ASME Press. - 9780791849835
  • Konferensbidrag (refereegranskat)abstract
    • Accurate structural modeling of blisk mistuning is critical for the analysis of forced response in turbomachinery. Apart from intentional mistuning, mistuning can be due to the manufacturing tolerances, corrosion, foreign object damage and in-service wear in general. It has been shown in past studies that mistuning can increase the risk of blade failure due to energy localization. For weak blade to blade coupling, this localization has been shown to be critical and higher amplitudes of vibration are expected in few blades. This paper presents a comparison of three reduced order models for the structural modeling of blisks. Two of the models assume cyclic symmetry while the third model is free of this assumption. The performance of the reduced order models for cases with small and large amount of mistuning will be examined. The benefits and drawbacks of each reduction method will be discussed.
  •  
46.
  • Gutman, Boris A, et al. (författare)
  • A meta-analysis of deep brain structural shape and asymmetry abnormalities in 2,833 individuals with schizophrenia compared with 3,929 healthy volunteers via the ENIGMA Consortium
  • 2022
  • Ingår i: Human Brain Mapping. - : John Wiley & Sons. - 1065-9471 .- 1097-0193. ; 43:1, s. 352-372
  • Tidskriftsartikel (refereegranskat)abstract
    • Schizophrenia is associated with widespread alterations in subcortical brain structure. While analytic methods have enabled more detailed morphometric characterization, findings are often equivocal. In this meta-analysis, we employed the harmonized ENIGMA shape analysis protocols to collaboratively investigate subcortical brain structure shape differences between individuals with schizophrenia and healthy control participants. The study analyzed data from 2,833 individuals with schizophrenia and 3,929 healthy control participants contributed by 21 worldwide research groups participating in the ENIGMA Schizophrenia Working Group. Harmonized shape analysis protocols were applied to each site's data independently for bilateral hippocampus, amygdala, caudate, accumbens, putamen, pallidum, and thalamus obtained from T1-weighted structural MRI scans. Mass univariate meta-analyses revealed more-concave-than-convex shape differences in the hippocampus, amygdala, accumbens, and thalamus in individuals with schizophrenia compared with control participants, more-convex-than-concave shape differences in the putamen and pallidum, and both concave and convex shape differences in the caudate. Patterns of exaggerated asymmetry were observed across the hippocampus, amygdala, and thalamus in individuals with schizophrenia compared to control participants, while diminished asymmetry encompassed ventral striatum and ventral and dorsal thalamus. Our analyses also revealed that higher chlorpromazine dose equivalents and increased positive symptom levels were associated with patterns of contiguous convex shape differences across multiple subcortical structures. Findings from our shape meta-analysis suggest that common neurobiological mechanisms may contribute to gray matter reduction across multiple subcortical regions, thus enhancing our understanding of the nature of network disorganization in schizophrenia.
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47.
  • Joseph, Laya, et al. (författare)
  • Non-Invasive Transmission Based Tumor Detection Using Anthropomorphic Breast Phantom at 2.45 GHz
  • 2020
  • Ingår i: 2020 14th European Conference on Antennas and Propagation (EuCAP). - 9788831299008 - 9781728137124
  • Konferensbidrag (refereegranskat)abstract
    • Breast cancer detection using microwave imaging techniques is a widely explored research field. In this paper, we propose the development of a heterogeneous, semi-solid and stable breast phantom with skin, fat, muscle and spherical tumor inclusion models and a transmission-based sensing method for non-invasive tumor detection. The proposed breast phantom emulates the anatomical, physical and dielectric properties as human breast tissues. The dielectric properties of the breast phantom is measured using open ended coaxial slim probe from Keysight Technologies and is compared with the Nello Carrara Institute of Applied Physics (IFAC) data in the frequency range of 500 MHz - 20GHz. The S 21 scattering parameter is measured and studied for a normal breast phantom and the breast phantom with tumor inclusion models representing its different growth stages using Topology Optimized Planar Antenna (TOPA) based probe. The measurements are done by using FieldFox microwave analyzer (N9918A) by Keysight Technologies. The study shows S 21 amplitude variation of 2 - 12 dB for tumor inclusion models of size ranging from 4mm - 16mm diameter with respect to normal breast model. This study indicates that with further development, transmission-based methods can be used for preliminary screening of breast tumor.
  •  
48.
  • Joura, Elmar A., et al. (författare)
  • HPV antibody levels and clinical efficacy following administration of a prophylactic quadrivalent HPV vaccine
  • 2008
  • Ingår i: Vaccine. - : Elsevier BV. - 1873-2518 .- 0264-410X. ; 26:52, s. 6844-6851
  • Tidskriftsartikel (refereegranskat)abstract
    • The efficacy of the quadrivalent Human Papillomavirus (HPV) vaccine is thought to be mediated by humoral immunity. We evaluated the correlation between quadrivalent HPV vaccine-induced serum anti-HPV responses and efficacy. 17,622 women were vaccinated at day 1, and months 2 and 6. At day I and at 6-12 months intervals for up to 48 months, subjects underwent Papanicolaou and genital HPV testing. No immune correlate of protection could be found due to low number of cases. Although 40% of vaccine subjects were anti-HPV 18 seronegative at end-of-study, efficacy against HPV 18-related disease remained high (98.4%; 95% CI: 90.5-100.0) despite high attack rates in the placebo group. These results suggest vaccine-induced protection via immune memory, or lower than detectable HPV 18 antibody titers. (C) 2008 Elsevier Ltd. All rights reserved.
  •  
49.
  • Kohler, Annegret, et al. (författare)
  • Convergent losses of decay mechanisms and rapid turnover of symbiosis genes in mycorrhizal mutualists.
  • 2015
  • Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1546-1718 .- 1061-4036. ; 47:4, s. 176-410
  • Tidskriftsartikel (refereegranskat)abstract
    • To elucidate the genetic bases of mycorrhizal lifestyle evolution, we sequenced new fungal genomes, including 13 ectomycorrhizal (ECM), orchid (ORM) and ericoid (ERM) species, and five saprotrophs, which we analyzed along with other fungal genomes. Ectomycorrhizal fungi have a reduced complement of genes encoding plant cell wall-degrading enzymes (PCWDEs), as compared to their ancestral wood decayers. Nevertheless, they have retained a unique array of PCWDEs, thus suggesting that they possess diverse abilities to decompose lignocellulose. Similar functional categories of nonorthologous genes are induced in symbiosis. Of induced genes, 7-38% are orphan genes, including genes that encode secreted effector-like proteins. Convergent evolution of the mycorrhizal habit in fungi occurred via the repeated evolution of a 'symbiosis toolkit', with reduced numbers of PCWDEs and lineage-specific suites of mycorrhiza-induced genes.
  •  
50.
  • Kommata, Varvara, et al. (författare)
  • QRS dispersion detected in ARVC patients and healthy gene carriers using 252-leads body surface mapping : an explorative study of a potential diagnostic tool for arrhythmogenic right ventricular cardiomyopathy
  • 2021
  • Ingår i: Pacing and Clinical Electrophysiology. - : Wiley. - 0147-8389 .- 1540-8159. ; 44:8, s. 1355-1364
  • Tidskriftsartikel (refereegranskat)abstract
    • BACKGROUND: The diagnosis of ARVC remains complex requiring both imaging and electrocardiographic (ECG) techniques. The purpose was therefore to investigate whether QRS dispersion assessed by body surface mapping (BSM) could be used to detect early signs of ARVC, particularly in gene carriers.METHODS: ARVC patients, gene carriers without a history of arrhythmias or structural cardiac changes and healthy controls underwent 12-lead resting ECG, signal-averaged ECG, echocardiographic examination, 24-hours Holter monitoring, and BSM with electrocardiographic imaging. All 252-leads BSM recordings and 12-leads ECG recordings were manually analyzed for QRS durations and QRS dispersion.RESULTS: Eight controls, 12 ARVC patients with definite ARVC and 20 healthy gene carriers were included. The ECG-QRS dispersion was significantly greater in ARVC patients (42 vs. 25 ms, p < .05), but failed to fully differentiate them from controls. The BSM-derived QRS dispersion was also significantly greater in ARVC patients versus controls (65 vs. 29 ms, p < .05) and distinguished 11/12 cases from controls using the cut-off 40msec. The BSM derived QRS dispersion was abnormal (> 40 ms) in 4/20 healthy gene carriers without signs of ARVC, which may indicate early depolarization changes.CONCLUSIONS: QRS dispersion, when assessed by BSM versus 12-lead ECG, seem to better distinguish ARVC patients from controls, and could potentially be used to detect early ARVC in gene carriers. Further studies are required to confirm the value of BSM-QRS dispersion in this respect.
  •  
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