Learning concurrently partition granularities and rule bases of Mamdani fuzzy systems in a multi-objective evolutionary framework

AbstractIn this paper we propose a multi-objective evolutionary algorithm to generate Mamdani fuzzy rule-based systems with different good trade-offs between complexity and accuracy. The main novelty of the algorithm is that both rule base and granularity of the uniform partitions defined on the input and output variables are learned concurrently. To this aim, we introduce the concepts of virtual and concrete rule bases: the former is defined on linguistic variables, all partitioned with a fixed maximum number of fuzzy sets, while the latter takes into account, for each variable, a number of fuzzy sets as determined by the specific partition granularity of that variable. We exploit a chromosome composed of two parts, which codify the variables partition granularities, and the virtual rule base, respectively. Genetic operators manage virtual rule bases, whereas fitness evaluation relies on an appropriate mapping strategy between virtual and concrete rule bases. The algorithm has been tested on two real-world regression problems showing very promising results

Assessing Nephrological Competence among Geriatricians: A Proof of Concept Internet Survey

Chronic kidney disease (CKD) is highly prevalent in the elderly and negatively impacts survival and health status. Thus, nephrological competence is mandatory for a skilled geriatrician. The present study aimed to assess nephrological competence in a sample of geriatricians recruited through a web survey. To this aim, a 12-items questionnaire was produced by an expert panel of nephrologists and geriatricians and was available online for members of the Italian Society of Gerontology and Geriatrics (SIGG). Two-hundred-eighty-seven geriatricians volunteered to fill in the questionnaire. The majority of them indirectly estimated the glomerular filtration rate (GFR) using mainly the Cockroft-Gault (C-G) formula. Selected nephrological exams, such as urinary Na and serum D-vitamin measurements, did not qualify as routine exams although the majority of geriatricians supplemented their patients with fat-soluble secosteroids. Ten percent of geriatricians asked for nephrological consultation only for stage 5 CKD patients and 30,9% only for stage 4 or 5. Erythropoietin supplementation was common practice for the majority of geriatricians, while only one third of them systematically used a procedure intended to prevent the contrast induced nephropathy (CIN). Finally, an alleged 50% adherence to the international guidelines for the management of CKD patients emerged from the questionnaire. Overall, results from this survey strongly recommend promoting nephrological education among geriatricians. Didactic standards for in training geriatricians need to be updated and the cooperation between geriatrics and nephrological societies promoted

Performance criteria and quality indicators for the post-analytical phase

Background: Quality indicators (QIs) used as performance measurements are an effective tool in accurately estimating quality, identifying problems that may need to be addressed, and monitoring the processes over time. In Laboratory Medicine, QIs should cover all steps of the testing process, as error studies have confirmed that most errors occur in the pre- and post-analytical phase of testing. Aim of the present study is to provide preliminary results on QIs and related performance criteria in the post-analytical phase. Methods: This work was conducted according to a previously described study design based on the voluntary -participation of clinical laboratories in the project on QIs of the Working Group "Laboratory Errors and Patient Safety" (WG-LEPS) of the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC). Results: Overall, data collected highlighted an improvement or stability in performances over time for all reported indicators thus demonstrating that the use of QIs is-effective in the quality improvement strategy. Moreover, QIs data are an important source for defining the state-of- the-art concerning the error rate in the total testing process. The definition of performance specifications based on the state-of-the-art, as suggested by consensus documents, is a valuable benchmark point in evaluating the performance of each laboratory. Conclusions: Laboratory tests play a relevant role in the monitoring and evaluation of the efficacy of patient outcome thus assisting clinicians in decision-making. Laboratory performance evaluation is therefore crucial to providing patients with safe, effective and efficient care

Polymorphism of Beta2-Adrenoceptor and Regular Use of Formoterol in Asthma: Preliminary Results

Polymorphism at codon 16 of the beta2-adrenoceptor (beta2-AR) affects the responsiveness to salmeterol in asthmatics. Data concerning formoterol are more controversial in the literature. The aim of this study was to verify whether homozygous for arginine-16 (ArgArg16) and homozygous for glycine-16 (GlyGly16) genotypes differently influence the long-term responsiveness to formoterol. Twenty-nine patients with mild-to-moderate asthma, in stable clinical conditions, underwent genotyping at codon 16 of the beta2-AR by RFLP-PCR assay. The effects of a 4-week monotherapy with formoterol (12 μg BID) were tested on the peak expiratory flow (PEF) variability and the forced expiratory volume in 1 sec (FEV1) slope of the dose-response curve to salbutamol. Variability in PEF significantly increased during the 4-week treatment period in 14 patients with GlyGly16, but not in 15 patients with ArgArg16 and ArgGly16 (P=0.032). The FEV1 slope of the dose-response curve to salbutamol decreased after the 4-week treatment period in GlyGly16, but not in pooled ArgArg16 and ArgGly16 patients. This study provides preliminary evidence that tolerance to formoterol develops more frequently in asthmatics with GlyGly16 genotype. If confirmed in a larger population, this finding might be useful in choosing the bronchodilator therapy on the basis of genetic polymorphism of the beta2-AR

Adult IDH wild-type glioblastoma ultrastructural investigation suggests a possible correlation between morphological biomarkers and Ki-67 index

Glioblastoma is an aggressive brain tumor with an average life expectancy between 14 and 16 months after diagnosis. The Ki-67 labeling index (LI), a measure of cellular proliferation, is emerging as a prognostic marker in GBM. In this study, we investigated the ultrastructure of glioblastoma tissue from 9 patients with the same molecular profile (adult IDH wild-type glioblastoma, wild-type ATRX, and positive for TP53 expression, GFAP expression, and EGFR overexpression) to find possible ultrastructural features to be used as biomarkers and correlated with the only parameter that differs among our samples, the Ki-67 LI. Our main results were the visualization of the anatomical basis of astrocyte-endothelial cells crosstalk; the ultrastructural in situ imaging of clusters of hyperactivated microglia cells (MsEVs); the ultrastructural in situ imaging of microglia cells storing lipid vesicles (MsLVs); the ultrastructural in situ imaging of neoplastic cells mitophagy (NCsM). The statistical analysis of our data indicated that MsEVs and MsLVs correlate with the Ki-67 LI value. We can thus assume they are good candidates to be considered morphological biomarkers correlating to Ki-67 LI. The role of NCsM instead must be further evaluated. Our study findings demonstrate that by combining ultrastructural characteristics with molecular information, we can discover biomarkers that have the potential to enhance diagnostic precision, aid in treatment decision-making, identify targets for therapy, and enable personalized treatment plans tailored to each patient. However, further research with larger sample sizes is needed to validate these findings and fully utilize the potential of ultrastructural analysis in managing glioblastoma

Dust tracking techniques applied to the STARDUST facility: First results

An important issue related to future nuclear fusion reactors fueled with deuterium and tritium is the creation of large amounts of dust due to several mechanisms (disruptions, ELMs and VDEs). The dust size expected in nuclear fusion experiments (such as ITER) is in the order of microns (between 0.1 and 1000 μm). Almost the total amount of this dust remains in the vacuum vessel (VV). This radiological dust can re-suspend in case of LOVA (loss of vacuum accident) and these phenomena can cause explosions and serious damages to the health of the operators and to the integrity of the device. The authors have developed a facility, STARDUST, in order to reproduce the thermo fluid-dynamic conditions comparable to those expected inside the VV of the next generation of experiments such as ITER in case of LOVA. The dust used inside the STARDUST facility presents particle sizes and physical characteristics comparable with those that created inside the VV of nuclear fusion experiments. In this facility an experimental campaign has been conducted with the purpose of tracking the dust re-suspended at low pressurization rates (comparable to those expected in case of LOVA in ITER and suggested by the General Safety and Security Report ITER-GSSR) using a fast camera with a frame rate from 1000 to 10,000 images per second. The velocity fields of the mobilized dust are derived from the imaging of a two-dimensional slice of the flow illuminated by optically adapted laser beam. The aim of this work is to demonstrate the possibility of dust tracking by means of image processing with the objective of determining the velocity field values of dust re-suspended during a LOVA

Role of 1p/19q Codeletion in Diffuse Low-grade Glioma Tumour Prognosis

Background/Aim: In the latest 2021 WHO classification of central nervous system tumours (CNS), gliomas that present isocitrate dehydrogenase (IDH) mutations are defined as diffuse low-grade gliomas (DLGGs). IDH mutations are commonly observed in this tumour type. The Extent of Resection (EOR) positively influence survival; however, it is still debated whether the predictive value of EOR is independent of the 1p/19q co-deletion. We carried out a retrospective analysis on patients operated on for DLGG at the Sant’Andrea University Hospital Sapienza University of Rome, correlating the outcome with the presence of 1p/19q co-deletion and EOR. Patients and Methods: The study examined 66 patients with DLGG who had undergone surgery for tumour resection between 2008 and 2018. Patients with DLGG were divided into two groups; diffuse astrocytoma (DA) in which 1p/19q codeletion is absent and oligodendroglioma (OG) in which 1p/19q codeletion is present. According to EOR, both groups were divided into two subgroups: subtotal resection (STR) and gross total resection (GTR). Three end-point variables were considered: overall survival (OS), progression-free survival (PFS) and time to malignant transformation (TMT). Results: In the DA group, the GTR subgroup had an average OS of 81.6 months, an average PFS of 45.9 months and an average TMT of 63.6 months. After surgery, these patients had an average Karnofsky Performance Score (KPS) of 83.4. The STR subgroup had an average OS of 60.4 months, PFS was 38.7 months, and TMT was 46.4 months, post-operative KPS was 83.4. In contrast, in the OG group, the GTR averagely had 101.7 months of OS, 64.9 months of PFS, 80.3 months of TMT and an average post-operative KPS of 84.2, and the STR subgroup had an average of OS of 73.3 months, PFS of 48.2 months, TMT of 57.3 and an average postoperative KPS of 96.2. Conclusion: In patients affected by DLGGs, 1p/19q codeletion is significantly associated with prolonged survival and longer time-to-malignant transformation (TMT) compared to the absence of 1p/19q codeletion. Also, the extent of surgical resection (EOR) in DLGG patients has been confirmed as one of the main prognostic factors. However, its predictive value is substantially influenced by the presence of the 1p/19q codeletion

Accessible Data Curation and Analytics for International-Scale Citizen Science Datasets

The Covid Symptom Study, a smartphone-based surveillance study on COVID-19 symptoms in the population, is an exemplar of big data citizen science. Over 4.7 million participants and 189 million unique assessments have been logged since its introduction in March 2020. The success of the Covid Symptom Study creates technical challenges around effective data curation for two reasons. Firstly, the scale of the dataset means that it can no longer be easily processed using standard software on commodity hardware. Secondly, the size of the research group means that replicability and consistency of key analytics used across multiple publications becomes an issue. We present ExeTera, an open source data curation software designed to address scalability challenges and to enable reproducible research across an international research group for datasets such as the Covid Symptom Study dataset

The effects of COVID-19 on cognitive performance in a community-based cohort: a COVID symptom study biobank prospective cohort study

BACKGROUND: Cognitive impairment has been reported after many types of infection, including SARS-CoV-2. Whether deficits following SARS-CoV-2 improve over time is unclear. Studies to date have focused on hospitalised individuals with up to a year follow-up. The presence, magnitude, persistence and correlations of effects in community-based cases remain relatively unexplored. METHODS: Cognitive performance (working memory, attention, reasoning, motor control) was assessed in a prospective cohort study of participants from the United Kingdom COVID Symptom Study Biobank between July 12, 2021 and August 27, 2021 (Round 1), and between April 28, 2022 and June 21, 2022 (Round 2). Participants, recruited from the COVID Symptom Study smartphone app, comprised individuals with and without SARS-CoV-2 infection and varying symptom duration. Effects of COVID-19 exposures on cognitive accuracy and reaction time scores were estimated using multivariable ordinary least squares linear regression models weighted for inverse probability of participation, adjusting for potential confounders and mediators. The role of ongoing symptoms after COVID-19 infection was examined stratifying for self-perceived recovery. Longitudinal analysis assessed change in cognitive performance between rounds. FINDINGS: 3335 individuals completed Round 1, of whom 1768 also completed Round 2. At Round 1, individuals with previous positive SARS-CoV-2 tests had lower cognitive accuracy (N = 1737, β = −0.14 standard deviations, SDs, 95% confidence intervals, CI: −0.21, −0.07) than negative controls. Deficits were largest for positive individuals with ≥12 weeks of symptoms (N = 495, β = −0.22 SDs, 95% CI: −0.35, −0.09). Effects were comparable to hospital presentation during illness (N = 281, β = −0.31 SDs, 95% CI: −0.44, −0.18), and 10 years age difference (60–70 years vs. 50–60 years, β = −0.21 SDs, 95% CI: −0.30, −0.13) in the whole study population. Stratification by self-reported recovery revealed that deficits were only detectable in SARS-CoV-2 positive individuals who did not feel recovered from COVID-19, whereas individuals who reported full recovery showed no deficits. Longitudinal analysis showed no evidence of cognitive change over time, suggesting that cognitive deficits for affected individuals persisted at almost 2 years since initial infection. INTERPRETATION: Cognitive deficits following SARS-CoV-2 infection were detectable nearly two years post infection, and largest for individuals with longer symptom durations, ongoing symptoms, and/or more severe infection. However, no such deficits were detected in individuals who reported full recovery from COVID-19. Further work is needed to monitor and develop understanding of recovery mechanisms for those with ongoing symptoms. FUNDING: Chronic Disease Research Foundation, Wellcome Trust, National Institute for Health and Care Research, Medical Research Council, British Heart Foundation, Alzheimer's Society, European Union, COVID-19 Driver Relief Fund, French National Research Agency