Macroscopic Aharonov--Bohm Effect in Type-I Superconductors

In type-I superconducting cylinders bulk superconductivity is destroyed above the first critical current. Below the second critical current the `type-I mixed state' displays fluctuation superconductivity which contributes to the total current. A magnetic flux on the axis of the cylinder can change the second critical current by as much as 50 percent so that half a flux quantum can switch the cylinder from normal conduction to superconductivity: the Aharonov--Bohm effect manifests itself in macroscopically large resistance changes of the cylinder.Comment: five pages, one figur

Two-subband quantum Hall effect in parabolic quantum wells

The low-temperature magnetoresistance of parabolic quantum wells displays pronounced minima between integer filling factors. Concomitantly the Hall effect exhibits overshoots and plateau-like features next to well-defined ordinary quantum Hall plateaus. These effects set in with the occupation of the second subband. We discuss our observations in the context of single-particle Landau fan charts of a two-subband system empirically extended by a density dependent subband separation and an enhanced spin-splitting g*.Comment: 5 pages, submitte

Day of Archaeology 2011–2017: Global Community, Public Engagement, and Digital Practice.

The Day of Archaeology (http://www.dayofarchaeology.com) was a volunteer-led international archaeological blogging event that ran from 2011 to 2017. The project asked people who define themselves as archaeologists to submit one or more blog posts about their working day on a chosen day in June or July. This article explores the history of the Day of Archaeology project and the practicalities of running a large-scale collaborative blogging project, before examining some of the topics covered in the posts. An assessment of the impact of the project follows. Overall, we hope in this work to answer some of the basic questions regarding this type of collaborative, online, global engagement – what we did, who we reached, what they talked about – and also to provide some insights for any other similar initiatives that may follow us in the future

Antibody signatures in patients with histopathologically defined multiple sclerosis patterns

Early active multiple sclerosis (MS) lesions can be classified histologically into three main immunopathological patterns of demyelination (patterns I-III), which suggest pathogenic heterogeneity and may predict therapy response. Patterns I and II show signs of immune-mediated demyelination, but only pattern II is associated with antibody/complement deposition. In pattern III lesions, which include Baló's concentric sclerosis, primary oligodendrocyte damage was proposed. Serum antibody reactivities could reflect disease pathogenesis and thus distinguish histopathologically defined MS patterns. We established a customized microarray with more than 700 peptides that represent human and viral antigens potentially relevant for inflammatory demyelinating CNS diseases, and tested sera from 66 patients (pattern I n = 12; II n = 29; III n = 25, including 8 with Baló's), healthy controls, patients with Sjögren's syndrome and stroke patients. Cell-based assays were performed for aquaporin 1 (AQP1) and AQP4 antibody detection. No single peptide showed differential binding among study cohorts. Because antibodies can react with different peptides from one protein, we also analyzed groups of peptides. Patients with pattern II showed significantly higher reactivities to Nogo-A peptides as compared to patterns I (p = 0.02) and III (p = 0.02). Pattern III patients showed higher reactivities to AQP1 (compared to pattern I p = 0.002, pattern II p = 0.001) and varicella zoster virus (VZV, compared to pattern II p = 0.05). In patients with Baló's, AQP1 reactivity was also significantly higher compared to patients without Baló's (p = 0.04), and the former revealed distinct antibody signatures. Histologically, Baló's patients showed loss of AQP1 and AQP4 in demyelinating lesions, but no antibodies binding conformational AQP1 or AQP4 were detected. In summary, higher reactivities to Nogo-A peptides in pattern II patients could be relevant for enhanced axonal repair and remyelination. Higher reactivities to AQP1 peptides in pattern III patients and its subgroup of Baló's patients possibly reflect astrocytic damage. Finally, latent VZV infection may cause peripheral immune activation

Serum peptide reactivities may distinguish neuromyelitis optica subgroups and multiple sclerosis

Objective: To assess in an observational study whether serum peptide antibody reactivities may distinguish aquaporin-4 (AQP4) antibody (Ab)–positive and -negative neuromyelitis optica spectrum disorders (NMOSD) and relapsing-remitting multiple sclerosis (RRMS). Methods: We screened 8,700 peptides that included human and viral antigens of potential relevance for inflammatory demyelinating diseases and random peptides with pooled sera from different patient groups and healthy controls to set up a customized microarray with 700 peptides. With this microarray, we tested sera from 66 patients with AQP4-Ab-positive (n = 16) and AQP4-Ab-negative (n = 19) NMOSD, RRMS (n = 11), and healthy controls (n = 20). Results: Differential peptide reactivities distinguished NMOSD subgroups from RRMS in 80% of patients. However, the 2 NMOSD subgroups were not well-discriminated, although those patients are clearly separated by their antibody reactivities against AQP4 in cell-based assays. Elevated reactivities to myelin and Epstein-Barr virus peptides were present in RRMS and to AQP4 and AQP1 peptides in AQP4-Ab-positive NMOSD. Conclusions: While AQP4-Ab-positive and -negative NMOSD subgroups are not well-discriminated by peptide antibody reactivities, our findings suggest that peptide antibody reactivities may have the potential to distinguish between both NMOSD subgroups and MS. Future studies should thus concentrate on evaluating peptide antibody reactivities for the differentiation of AQP4-Ab-negative NMOSD and MS

Is benign MS really benign? What a meaningful classification beyond the EDSS must take into consideration

BACKGROUND: Multiple sclerosis (MS) is a neuroinflammatory and neurodegenerative disease with an unpredictable course that has a broad clinical spectrum and progresses over time. If a person with MS (PwMS) shows overall mild to moderate disability even after a long duration of disease, the term benign MS (BMS) is used. However, there is currently no generally accepted definition of BMS. Most definitions are based on EDSS in connection with disease duration, i.e. EDSS ≤3.0 after 15 years' disease duration. The question arises whether focusing on EDSS alone is adequate for classifying the disease course taking into account that 'hidden' or 'soft' symptoms are not sufficiently covered by this instrument. The aims of the study are to assess the prevalence of BMS in one of the largest patient cohorts, to describe the prevalence of patients without disabilities and to assess the further disability progression of these patients over another 15 years. METHODS: Based on data exported from the German MS Registry, PwMS with a disease duration of 15 years or more were included in the analyses. PwMS were divided into BMS (EDSS ≤3.0) or non-benign (NBMS, EDSS >3.0). RESULTS: Out of 31,824 PwMS included in the German MS Register, we identified 10,874 patients with a disease duration ≥15 years of whom 4,511 (42%) showed an EDSS ≤3.0 fulfilling the criterion of benign MS. In the subgroup with EDSS measured exactly at 15 years' disease duration, the proportion was 54%. This proportion decreased continuously with increasing disease duration and fell to 30% after 30 years. Female sex (hazard ratio [HR]: 0.84) was associated with BMS, while a progressive (HR: 2.09) and late disease onset (HR: 1.29) were associated with NBMS (p<0.001). With a more rigorous definition of BMS (EDSS ≤1.0, absence of disability, and active employment), only 580 (13%) of the initial BMS remained 'benign'. CONCLUSION: Our data propose an alternative definition (EDSS ≤1.0, absence from any disability, and the ability to work after 15 years of disease duration) which might truly reflect BMS

Extending the footprint record of Pareiasauromorpha to the Cisuralian : earlier appearance and wider palaeobiogeography of the group

Pareiasauromorpha is one of the most important tetrapod groups of the Permian. Skeletal evidence suggests a late Kungurian origin in North America, whereas the majority of occurrences come from the Guadalupian and Lopingian of South Africa and Russia. However, Pareiasauromorpha footprints include the ichnogenus Pachypes, which is unknown from strata older than late Guadalupian. A revision of several Pachypes-like footprints from the Cisuralian-Guadalupian of Europe and North America confirm the occurrence of this ichnogenus and of the ichnospecies Pachypes ollieri comb. nov. beginning in the Artinskian. This is the earliest known occurrence of Pachypes and it coincides with the Artinskian reptile radiation. Based on a synapomorphy-based track-trackmaker correlation, P. ollieri can be attributed to nycteroleter pareiasauromorphs such as Macroleter. Therefore, the earliest occurrences of pareiasauromorph footprints precede by at least 10 myr the earliest occurrence of this group in the skeletal record. Moreover, the palaeobiogeography of the group is extended to the Cisuralian and Guadalupian of western Europe

Automated segmentation of normal and diseased coronary arteries – The ASOCA challenge

Cardiovascular disease is a major cause of death worldwide. Computed Tomography Coronary Angiography (CTCA) is a non-invasive method used to evaluate coronary artery disease, as well as evaluating and reconstructing heart and coronary vessel structures. Reconstructed models have a wide array of for educational, training and research applications such as the study of diseased and non-diseased coronary anatomy, machine learning based disease risk prediction and in-silico and in-vitro testing of medical devices. However, coronary arteries are difficult to image due to their small size, location, and movement, causing poor resolution and artefacts. Segmentation of coronary arteries has traditionally focused on semi-automatic methods where a human expert guides the algorithm and corrects errors, which severely limits large-scale applications and integration within clinical systems. International challenges aiming to overcome this barrier have focussed on specific tasks such as centreline extraction, stenosis quantification, and segmentation of specific artery segments only. Here we present the results of the first challenge to develop fully automatic segmentation methods of full coronary artery trees and establish the first large standardized dataset of normal and diseased arteries. This forms a new automated segmentation benchmark allowing the automated processing of CTCAs directly relevant for large-scale and personalized clinical applications