250 research outputs found
Recommended from our members
Comparison of 5-year progression of retinitis pigmentosa involving the posterior pole among siblings by means of SD-OCT: a retrospective study
The blockchain technology promises to transform finance, money and evengovernments. However, analyses of blockchain applicability and robustness typicallyfocus on isolated systems whose actors contribute mainly by running the consensusalgorithm. Here, we highlight the importance of considering trustless platformswithin the broader ecosystem that includes social and communication networks. Asan example, we analyse the flash-crash observed on 21st June 2017 in the Ethereumplatform and show that a major phenomenon of social coordination led to acatastrophic cascade of events across several interconnected systems. We proposethe concept of “emergent centralisation” to describe situations where a single systembecomes critically important for the functioning of the whole ecosystem, and arguethat such situations are likely to become more and more frequent in interconnectedsocio-technical systems. We anticipate that the systemic approach we propose willhave implications for future assessments of trustless systems and call for the attentionof policy-makers on the fragility of our interconnected and rapidly changing world
Widening the divide: the impact of school closures on primary science learning
Prolonged Covid-19-related school closures in the UK raised concerns that science teaching and learning at primary level would be negatively impacted. This paper reports the findings of phase 1 of a study that the authors are conducting with teachers and parents to explore this issue. We found that a significant proportion of teachers were providing less science during lockdown than in the normal school week. Teachers, particularly those working in more deprived areas, reported that translating the science curriculum for home learning had been difficult, with concerns around resources, internet access and parental ability to help. Some areas of the curriculum posed particular difficulties, leading to a narrowing of topics being taught. Both teachers and parents felt that schools prioritised English and maths above science. Meanwhile some parents reported that their children had engaged in sophisticated extracurricular activities, bolstered by resources available at home and knowledgeable adult help, but others said that their children had done no science at all. Parents who had studied science at post-compulsory level were much more comfortable in helping their children with science home learning. These factors combine to create conditions which may exacerbate existing inequalities as to who can access science education and careers
Evaluation of a large set of patients with Autoimmune Polyglandular Syndrome from a single reference centre in context of different classifications
Purpose: To characterize patients with APS and to propose a new approach for their follow-up. Query ID="Q1" Text="Please check the given names and familynames." Methods: Monocentric observational retrospective study enrolling patients referred to the Outpatients clinic of the Units of Endocrinology, Diabetology, Gastroenterology, Rheumatology and Clinical Immunology of our Hospital for Autoimmune diseases. Results: Among 9852 patients, 1174 (11.9%) [869 (73.9%) female] were diagnosed with APS. In 254 subjects, the diagnosis was made at first clinical evaluation (Group 1), all the other patients were diagnosed with a mean latency of 11.3 ± 10.6 years (Group 2). Group 1 and 2 were comparable for age at diagnosis (35.7 ± 16.3 vs. 40.4 ± 16.6 yrs, p =.698), but different in male/female ratio (81/173 vs 226/696, p =.019). In Group 2, 50% of patients developed the syndrome within 8 years of follow-up. A significant difference was found after subdividing the first clinical manifestation into the different outpatient clinic to which they referred (8.7 ± 8.0 vs. 13.4 ± 11.6 vs. 19.8 ± 8.7 vs. 7.4 ± 8.1 for endocrine, diabetic, rheumatologic, and gastroenterological diseases, respectively, p <.001). Conclusions: We described a large series of patients affected by APS according to splitters and lumpers. We propose a flowchart tailored for each specialist outpatient clinic taking care of the patients. Finally, we recommend regular reproductive system assessment due to the non-negligible risk of developing premature ovarian failure
The Bcl I single nucleotide polymorphism of the human glucocorticoid receptor gene h-GR/NR3C1 promoter in patients with bronchial asthma: pilot study
Bcl I in the promoter polymorphism observed within h-GR/NR3C1 gene may play an important role in the development of bronchial asthma and resistance to GCs in the severe bronchial asthma. The aim of the investigation was to study the correlation between this h-GR/NR3C1 gene polymorphism and occurrence of asthma in the population of Polish asthmatics. Peripheral blood was obtained from 70 healthy volunteers and 59 asthma patients. Structuralized anamnesis, spirometry and allergy skin prick tests were performed in all participants. Genotyping was carried out with PCR–RFLP method. In healthy, non-atopic population variants of Bcl I: GG, GC, CC were found with frequency 0.129/0.471/0.400, respectively. In asthma patients Bcl I: GG, GC, CC occurred with respective frequencies of 0.410/0.462/0.128. Chi-square analysis revealed a significantly different (P < 0.05) distribution between cases and controls for the Bcl I polymorphism. The Bcl I polymorphism of h-GR/NR3C1 gene is significantly associated with bronchial asthma, susceptibility to the development of severe form and resistance to GCs in Polish population
Outlining a new collaborative business model as a result of the green Building Information Modelling impact in the AEC supply chain
BIM (Building Information Modelling) technological push has enabled to integrate the design/construction outcomes of 3D-CAD along the product/service AEC (Architecture, Engineering and Construction) SC (supply chain) through an intelligent DMS (Data Management System) based on standard and interoperable data formats. The proposed end-to-end approach overcomes a typical AEC gap, enables the operationalisation of the sustainable/green building LCA (Life Cycle Assessment) and puts together new collaborative relationships with the owner, among SC stakeholders and with new forms of BIM procurement. The outlined collaborative business model is based on the Quality Control and Assurance framework and provides conceptual consistency to the reintroduction of the owner concerns/satisfaction in the SC, as well as enables consistent and accountable relationships between (smart)materials procurement and building specification. An expert’s focus group carried out a preliminary check of the model’s interest/applicability, resulting in recommendations for its further detailing and for propositions development into a systematic enquiring process.info:eu-repo/semantics/acceptedVersio
Habitat-Mediated Facilitation and Counteracting Ecosystem Engineering Interactively Influence Ecosystem Responses to Disturbance
Recovery of an ecosystem following disturbance can be severely hampered or even shift altogether when a point disturbance exceeds a certain spatial threshold. Such scale-dependent dynamics may be caused by preemptive competition, but may also result from diminished self-facilitation due to weakened ecosystem engineering. Moreover, disturbance can facilitate colonization by engineering species that alter abiotic conditions in ways that exacerbate stress on the original species. Consequently, establishment of such counteracting engineers might reduce the spatial threshold for the disturbance, by effectively slowing recovery and increasing the risk for ecosystem shifts to alternative states. We tested these predictions in an intertidal mudflat characterized by a two-state mosaic of hummocks (humps exposed during low tide) dominated by the sediment-stabilizing seagrass Zostera noltii) and hollows (low-tide waterlogged depressions dominated by the bioturbating lugworm Arenicola marina). In contrast to expectations, seagrass recolonized both natural and experimental clearings via lateral expansion and seemed unaffected by both clearing size and lugworm addition. Near the end of the growth season, however, an additional disturbance (most likely waterfowl grazing and/or strong hydrodynamics) selectively impacted recolonizing seagrass in the largest (1 m2) clearings (regardless of lugworm addition), and in those medium (0.25 m2) clearings where lugworms had been added nearly five months earlier. Further analyses showed that the risk for the disturbance increased with hollow size, with a threshold of 0.24 m2. Hollows of that size were caused by seagrass removal alone in the largest clearings, and by a weaker seagrass removal effect exacerbated by lugworm bioturbation in the medium clearings. Consequently, a sufficiently large disturbance increased the vulnerability of recolonizing seagrass to additional disturbance by weakening seagrass engineering effects (sediment stabilization). Meanwhile, the counteracting ecosystem engineering (lugworm bioturbation) reduced that threshold size. Therefore, scale-dependent interactions between habitat-mediated facilitation, competition and disturbance seem to maintain the spatial two-state mosaic in this ecosystem
Stat3 controls cell death during mammary gland involution by regulating uptake of milk fat globules and lysosomal membrane permeabilization.
We have previously demonstrated that Stat3 regulates lysosomal-mediated programmed cell death (LM-PCD) during mouse mammary gland involution in vivo. However, the mechanism that controls the release of lysosomal cathepsins to initiate cell death in this context has not been elucidated. We show here that Stat3 regulates the formation of large lysosomal vacuoles that contain triglyceride. Furthermore, we demonstrate that milk fat globules (MFGs) are toxic to epithelial cells and that, when applied to purified lysosomes, the MFG hydrolysate oleic acid potently induces lysosomal leakiness. Additionally, uptake of secreted MFGs coated in butyrophilin 1A1 is diminished in Stat3-ablated mammary glands and loss of the phagocytosis bridging molecule MFG-E8 results in reduced leakage of cathepsins in vivo. We propose that Stat3 regulates LM-PCD in mouse mammary gland by switching cellular function from secretion to uptake of MFGs. Thereafter, perturbation of lysosomal vesicle membranes by high levels of free fatty acids results in controlled leakage of cathepsins culminating in cell death.This work was
supported by a grant from the Medical Research Council programme grant no. MR/J001023/1 (T.J.S. and B. L-L.)
and a Cancer Research UK Cambridge Cancer Centre PhD studentship (H.K.R.).This is the accepted manuscript. The final version is available from Nature Publishing at http://www.nature.com/ncb/journal/vaop/ncurrent/full/ncb3043.html
- …