A qualitative and quantitative analysis of open citations to retracted articles: the Wakefield 1998 et al.'s case

In this article, we show the results of a quantitative and qualitative analysis of open citations on a popular and highly cited retracted paper: “Ileal-lymphoid-nodular hyperplasia, non-specific colitis and pervasive developmental disorder in children” by Wakefield et al., published in 1998. The main purpose of our study is to understand the behavior of the publications citing one retracted article and the characteristics of the citations the retracted article accumulated over time. Our analysis is based on a methodology which illustrates how we gathered the data, extracted the topics of the citing articles and visualized the results. The data and services used are all open and free to foster the reproducibility of the analysis. The outcomes concerned the analysis of the entities citing Wakefield et al.’s article and their related in-text citations. We observed a constant increasing number of citations in the last 20 years, accompanied with a constant increment in the percentage of those acknowledging its retraction. Citing articles have started either discussing or dealing with the retraction of Wakefield et al.’s article even before its full retraction happened in 2010. Articles in the social sciences domain citing the Wakefield et al.’s one were among those that have mostly discussed its retraction. In addition, when observing the in-text citations, we noticed that a large number of the citations received by Wakefield et al.’s article has focused on general discussions without recalling strictly medical details, especially after the full retraction. Medical studies did not hesitate in acknowledging the retraction of the Wakefield et al.’s article and often provided strong negative statements on it

The OpenCitations Data Model

A variety of schemas and ontologies are currently used for the machine-readable description of bibliographic entities and citations. This diversity, and the reuse of the same ontology terms with different nuances, generates inconsistencies in data. Adoption of a single data model would facilitate data integration tasks regardless of the data supplier or context application. In this paper we present the OpenCitations Data Model (OCDM), a generic data model for describing bibliographic entities and citations, developed using Semantic Web technologies. We also evaluate the effective reusability of OCDM according to ontology evaluation practices, mention existing users of OCDM, and discuss the use and impact of OCDM in the wider open science community.Comment: ISWC 2020 Conference proceeding

High genetic diversity within and among bitter cassava cultivated in three soil types in Central Amazonia.

Bitter cassava is an important food crop that was domesticated in Amazonia. Although it is exclusively propagated by stem cuttings, cassava retained its ability of sexual reproduction. The occurrence and incorporation of sexual plants into the stock of clonal varieties contributes to the high genetic diversity observed within the crop. Despite being well adapted to nutrient deprived soils of Amazonia, ethnobotanical observations showed that communities of smallholder farmers along the middle Madeira River, in Central Amazonia, also cultivate cassava in the highly fertile soils of the floodplains and Amazonian dark earths (ADE). These farmers grow different sets of varieties in each soil type, which may also contribute to the maintenance of high levels of genetic diversity within the crop. We evaluated with 10 nuclear microsatellite markers the genetic diversity within and among some of the most commonly cultivated bitter cassava varieties grown on ADE, floodplain and Oxisols soils in the middle Madeira region. High levels of genetic diversity within varieties were observed (HO ranging from 0.495 to 0.707, and HE ranging from 0.250 to 0.460). Additionally, varieties were generally highly differentiated from each other. Although high levels of genetic diversity were previously observed in studies carried out in regions of low soil fertility in other parts of Amazonia, we identified that management of different soil types is important to the maintenance of genetically distinct stocks of varieties, which also contributes to the maintenance of the genetic diversity within the crop

imaging the coupling of terahertz radiation to a high electron mobility transistor in the near field

We used AlGaN/GaN high electron mobility transistors as room-temperature direct detectors of radiation at 0.15 THz from a free electron laser, hence 5 times higher than their cutoff frequency of 30 GHz. By near-field active mapping we investigated the antenna-like coupling of the radiation to the transistor channel. We formulate a model for the detection based on self-mixing in the transistor channel. The noise equivalent power is found in the range of 10^{-7} W/Hz^{0.5} without any optimization of the device responsivity. Present day AlGaN/GaN fabrication technology may provide operation at higher frequency, integration of amplifiers for improved responsivity and fast switches for multiplexing, which make the detector here described the basic element of a monolithic terahertz focal plane array

Perception, knowledge and attitude towards childhood fever: A survey among final-year medical students

Aims: Undue concerns about the consequences of fever and its inappropriate management have been documented worldwide among physicians. However, no data exist on medical students. We investigated the perception, knowledge and attitude towards childhood fever among final-year medical students. Methods: Between June and September 2021, final-year medical students of six Italian universities were invited to complete an online survey on their conceptions and attitude towards pharmacological and non-pharmacological management of childhood fever. History of relevant personal or second-hand experience with childhood fever was also addressed. Both quantitative and qualitative approaches were used. Results: Of 1095 (69%) final-year medical students, 756 completed the survey. Many students believe that high fever might cause brain damage, would recommend physical methods and alternate two drugs for fever. Most students do not think that fever has mainly beneficial effects. In Northern Italy, students are less likely to believe that fever might lead to brain damage (OR 0.55, 95% CI 0.33-0.94), and in Southern Italy students are more likely to advise physical methods (OR 1.77, 95% CI 1.22-2.57) and less likely to believe that fever has mainly beneficial effects (OR 0.55, 95% CI 0.39-0.77). History of a relevant personal episode of fever during childhood was not associated with these outcomes. Conclusions: Misconceptions about fever are common among final-year medical students in Italy. Cultural factors rather than individually learned traits might underlie these beliefs. Medical students are a promising target for educational interventions to improve childhood fever management

Impact of multiple sclerosis risk loci in postinfectious neurological syndromes

Background: The genetic component of multiple sclerosis (MS) is now set to 200 autosomal common variants. However, it is unclear how genetic knowledge be clinically used in the differential diagnosis between MS and other inflammatory conditions like adult-onset postinfectious neurological syndromes (PINS). The aim of this study was to investigate whether PINS and MS have a shared genetic background using an updated polygenic risk scores. / Methods: Eighty-eight PINS patients have been consecutively recruited between 1996 and 2016 at Mondino Foundation of Pavia, diagnosed according to clinical, MRI and CSF findings and followed-up for several years. Patients were typed using Illumina array, and genotypes imputed using the 1000 Genomes Project reference panel. A weighted genetic risk score (wGRS) has been calculated based on autosomal MS risk loci derived from large-scale studies, and an HLA genetic burden (HLAGB) was also calculated on loci associated to MS. / Results: PINS occurred as an episode of myelitis in 44% of patients, encephalomyelitis in 44%, and encephalitis in remaining cases, with an involvement of peripheral nervous system in 41% of patients. Mean age of onset was 50.1 years, and female:male ratio was 1.4. Patients were followed-up for a mean of 7.2 years, and at last visit 55% had a low disability grade (mRS 0–1). Disease was monophasic in 67% of patients, relapsing in 18% and chronic-progressive in 15%. The wGRS of PINS cases was comparable to 370 healthy controls, while significantly lower compared to 907 bout-onset MS (BOMS) cases (wGRS= 20.9 vs 21.2; p<0.0001). The difference was even larger for PINS with peripheral nervous system involvement (wGRS=20.6) vs BOMS. / Conclusion: The distinction between MS and PINS is not easy to make in clinical practice. However, our study shows that the new set of MS risk alleles does not confer increased susceptibility to PINS. These data support the importance to discriminate these cases from MS with pathophysiological and therapeutic implications

NLRP3 polymorphisms and response to interferon-beta in multiple sclerosis patients

Evidence exists for a potential modulation of inflammasome activity by interferon beta. Here, we investigated the roles of inflammasomes [absent in melanoma 2 (AIM2); NLR family, CARD domain containing 4 (NLRC4); NLR family, pyrin domain containing 1 and 3 (NLRP1 and NLRP3)] and related cytokines (IL1B, IL10, IL18) in the response to interferon beta in patients with relapsing-remitting multiple sclerosis. Ninety-seven patients treated with interferon beta were classified into responders and non-responders according to clinical criteria after 24 months and clinical-radiological criteria after 12 months of treatment. Messenger RNA expression levels of inflammasomes and cytokines were determined by real-time polymerase chain reaction in peripheral blood mononuclear cells collected before treatment with interferon beta. In a subgroup of patients, NLRP3 and IL1B expression was also determined after 3 months (n = 32) and 12 months (n = 20) of interferon beta treatment. A polymorphism located in the NLRP3 gene, rs35829419, was genotyped in 789 multiple sclerosis patients treated with interferon beta. Baseline mRNA expression levels for NLRP3 and IL1B were increased in peripheral blood mononuclear cells from non-responders compared to responders classified according to clinical criteria after 24 months (P = 0.02 and P = 0.001, respectively). No significant differences were observed for other inflammasomes and related cytokines. Differences in NLRP3 and IL1B expression remained significant following a clinical-radiological classification after 12 months (P = 0.007 and P = 0.02, respectively). After treatment with interferon beta, NLRP3 and IL1B expression was increased in responders but unchanged in non-responders. A trend for association was observed between rs35829419 and interferon beta response (pM-H = 0.08). These results point to a role of the NLRP3 inflammasome and its related cytokine IL1B in the response to interferon beta in patients with relapsing-remitting multiple sclerosis