Marinari-Parisi and Supersymmetric Collective Field Theory

A field theoretic formulation of the Marinari-Parisi supersymmetric matrix model is established and shown to be equivalent to a recently proposed supersymmetrization of the bosonic collective string field theory. It also corresponds to a continuum description of super-Calogero models. The perturbation theory of the model is developed and, in this approach, an infinite sequence of vertices is generated. A class of potentials is identified for which the spectrum is that of a massless boson and Majorana fermion. For the harmonic oscillator case, the cubic vertices are obtained in an oscillator basis. For a rather general class of potentials it is argued that one cannot generate from Marinari-Parisi models a continuum limit similar to that of the d=1 bosonic string.Comment: 45 page

The superfield quantisation of a superparticle action with an extended line element

A massive superparticle action based on the generalised line element in N = 1 global superspace is quantised canonically. A previous method of quantising this action, based on a Fock space analysis, showed that states existed in three supersymmetric multiplets, each of a different mass. The quantisation procedure presented uses the single first class constraint as an operator condition on a general N = 1 superwavefunction. The constraint produces coupled equations of motion for the component wavefunctions. Transformations of the component wavefunctions are derived that decouple the equations of motion and partition the resulting wavefunctions into three separate supermultiplets. Unlike previous quantisations of superparticle actions in N = 1 global superspace, the spinor wavefunctions satisfy the Dirac equation and the vector wavefunctions satisfy the Proca equation. The off-shell closure of the commutators of the supersymmetry transformations, that include mass parameters, are derived by the introduction of auxiliary wavefunctions. To avoid the ghosts arising in a previous Fock space quantisation an alternative conjugation is used in the definition of the current, based on a Krein space approach

Scientific collaboration with educators: practical insights from an in‐class noise‐reduction intervention

Moving the field of Mind, Brain, and Education forward requires researchers and educators to reframe the boundaries of their own discipline in order to create knowledge that is both scientifically based, and of practical relevance for education. We believe that this could be done by co‐constructing research projects from the start. We present a case study of a noise‐reduction intervention in elementary classrooms, in which teachers and researchers worked together from the onset of study design. We examine the processes behind: (1) selecting research questions and measures, (2) planning interventions, (3) receiving ethical approval and funding, (4) recruiting schools, and (5) collecting data. At each step, our study provides suggestions for future collaborative efforts, keeping in mind broader theoretical and methodological implications. We believe that our concrete examples and suggestions will be useful for beginning and confirmed researchers, as well as teachers aiming to know more about research projects

A cost effective public transport management system for go!durban

The eThekwini Transport Authority (ETA) is implementing an Integrated Public Transport Network (Go!Durban) which is essentially a traditional BRT system. Go!Durban requires a Public Transport Management System (PTMS) in order to monitor the performance and compliance of the BRT operator and provide real time information on the BRT system. In 2014, the ETA advertised a tender for an Advanced PTMS. The lowest tender to specification was priced at around R350 million. This was deemed too expensive, and the tender was not awarded. Subsequent to this, in 2018 the ETA commenced discussions with Netstar, the current eThekwini fleet management contractor, to extend their fleet management system to include compliance monitoring, thus meeting the core functionality of a PTMS. The Go!Durban team developed a minimum User Requirements Specification (URS), based on the original ETA APTMS specification, which Netstar then used to map their proposal and cost estimate to develop the system. The system is being developed in two phases with a Proof of Concept or Pilot phase, building on their existing system functionality, followed by a Phase 2 to address the gaps in the APTMS minimum URS – essentially functionality that required further development. Based on the Netstar fleet management system, the ETA has thus developed a cost-effective PTMS to support the operations of the Go! Durban Integrated Public Transport Network (IPTN). This PTMS Lite system provides the essential functionality of the traditional PTMS at a fraction of the cost. The ETA PTM Lite System is a tool to manage bus movements against a static timetable on the Go!Durban corridors and provide appropriate reporting and bus communication for the Transport Operator. In order to drive down operational costs (and therefore subsidies) ITS practitioners have a significant role to play in looking for cost effective solutions. The Netstar system presented here offers significant cost savings for capital and operating budgets. It offers an application centric solution for passenger information and provides all the essential functionality of a traditional APTMS at around a tenth of the cost. This should assist planners in their quest for a more financially sustainable public transport system.Papers presented virtually at the 39th International Southern African Transport Conference on 05 -07 July 202

Antigenic diversity is generated by distinct evolutionary mechanisms in African trypanosome species

Antigenic variation enables pathogens to avoid the host immune response by continual switching of surface proteins. The protozoan blood parasite Trypanosoma brucei causes human African trypanosomiasis ("sleeping sickness") across sub-Saharan Africa and is a model system for antigenic variation, surviving by periodically replacing a monolayer of variant surface glycoproteins (VSG) that covers its cell surface. We compared the genome of Trypanosoma brucei with two closely related parasites Trypanosoma congolense and Trypanosoma vivax, to reveal how the variant antigen repertoire has evolved and how it might affect contemporary antigenic diversity. We reconstruct VSG diversification showing that Trypanosoma congolense uses variant antigens derived from multiple ancestral VSG lineages, whereas in Trypanosoma brucei VSG have recent origins, and ancestral gene lineages have been repeatedly co-opted to novel functions. These historical differences are reflected in fundamental differences between species in the scale and mechanism of recombination. Using phylogenetic incompatibility as a metric for genetic exchange, we show that the frequency of recombination is comparable between Trypanosoma congolense and Trypanosoma brucei but is much lower in Trypanosoma vivax. Furthermore, in showing that the C-terminal domain of Trypanosoma brucei VSG plays a crucial role in facilitating exchange, we reveal substantial species differences in the mechanism of VSG diversification. Our results demonstrate how past VSG evolution indirectly determines the ability of contemporary parasites to generate novel variant antigens through recombination and suggest that the current model for antigenic variation in Trypanosoma brucei is only one means by which these parasites maintain chronic infections

Extending scientific computing system with structural quantum programming capabilities

We present a basic high-level structures used for developing quantum programming languages. The presented structures are commonly used in many existing quantum programming languages and we use quantum pseudo-code based on QCL quantum programming language to describe them. We also present the implementation of introduced structures in GNU Octave language for scientific computing. Procedures used in the implementation are available as a package quantum-octave, providing a library of functions, which facilitates the simulation of quantum computing. This package allows also to incorporate high-level programming concepts into the simulation in GNU Octave and Matlab. As such it connects features unique for high-level quantum programming languages, with the full palette of efficient computational routines commonly available in modern scientific computing systems. To present the major features of the described package we provide the implementation of selected quantum algorithms. We also show how quantum errors can be taken into account during the simulation of quantum algorithms using quantum-octave package. This is possible thanks to the ability to operate on density matrices

Inferring Mycobacterium bovis transmission between cattle and badgers using isolates from the Randomised Badger Culling Trial.

Mycobacterium bovis (M. bovis) is a causative agent of bovine tuberculosis, a significant source of morbidity and mortality in the global cattle industry. The Randomised Badger Culling Trial was a field experiment carried out between 1998 and 2005 in the South West of England. As part of this trial, M. bovis isolates were collected from contemporaneous and overlapping populations of badgers and cattle within ten defined trial areas. We combined whole genome sequences from 1,442 isolates with location and cattle movement data, identifying transmission clusters and inferred rates and routes of transmission of M. bovis. Most trial areas contained a single transmission cluster that had been established shortly before sampling, often contemporaneous with the expansion of bovine tuberculosis in the 1980s. The estimated rate of transmission from badger to cattle was approximately two times higher than from cattle to badger, and the rate of within-species transmission considerably exceeded these for both species. We identified long distance transmission events linked to cattle movement, recurrence of herd breakdown by infection within the same transmission clusters and superspreader events driven by cattle but not badgers. Overall, our data suggests that the transmission clusters in different parts of South West England that are still evident today were established by long-distance seeding events involving cattle movement, not by recrudescence from a long-established wildlife reservoir. Clusters are maintained primarily by within-species transmission, with less frequent spill-over both from badger to cattle and cattle to badger

Creation of 21st century anatomy facilities : designing facilities for integrated preclinical education in the Middle East

DATA AVAILABILITY : The original contributions presented in the study are included in the article and any further inquiries can be directed to the corresponding author.BACKGROUND : The establishment of new anatomy facilities needs to accommodate a combination of modern teaching modalities that best align with evidence-based best teaching practices. This article describes the process in which our state-of-the-art anatomy laboratories were designed and implemented, and how these facilities support aspects of modern anatomy education. METHODS : A list of best practices for anatomy education in a modern medical curriculum was summarized from the literature. To assess student satisfaction, a survey related to student perception of the anatomy facilities (5-point Likert scale) was conducted. RESULTS : Our educational modalities include a broad range of teaching approaches. The Instructional Studio houses prosected and plastinated specimens, and cadaveric dissections are performed. Each of our three Dry Laboratories allow for active learning and interaction between small student groups. The Webinar Room acts as a conference room for departmental and online meetings, discussions with students, and dialogues with affiliated hospitals via the internet. The Imaging Center is equipped with a Sectra® medical educational platform, CAE Vimedix® Virtual Medical Imaging Ultrasound Training System, and Philipps Lumify® Ultrasound devices to train students to conduct and interpret sonographic images. Moreover, the Complete Anatomy® program is made available to all our students. CONCLUSION : The layout of our newly created Anatomy Facilities allows for all aspects of modern medical education mentioned in the literature. These educational modalities and teaching approaches are highly appreciated by our faculty and students. Moreover, these technologies allowed for a smooth transition from on-site anatomy teaching to online education during the COVID pandemic.https://bmcmededuc.biomedcentral.comam2024AnatomySDG-04:Quality Educatio