Virtual libraries of tissue and clinical samples: potential role of a 3-D microscope.

Our international innovative teaching group from different European Universities (De Montfort University, DMU, UK; and the Spanish University of Alcalá, University Miguel Hernández and University of San Pablo CEU), in conjunction with practicing biomedical scientists in the National Health Service (UK) and biomedical researchers, are developing two complete e-learning packages for teaching and learning medical parasitology, named DMU e-Parasitology (accessible at: http://parasitology.dmu.ac.uk), and biology and chemistry, named DMU e-Biology (accessible at: http://parasitology.dmu.ac.uk/ebiology/index.htm), respectively. Both packages will include a virtual microscope with a complete library of digitised tissue images, clinical slides and cell culture slides/mini-videos for enhancing the teaching and learning of a myriad of techniques applicable to health science undergraduate and postgraduate students. Thus, these packages include detecting human parasites, by becoming familiar with their infective structures and/or organs (e.g. eggs, cysts) and/or explore pathogenic tissues stained with traditional (e.g. haematoxylin & eosin) or more modern (e.g. immunohistochemistry) techniques. The Virtual Microscope (VM) module in the DMU e-Parasitology package is almost completed (accessible at: http://parasitology.dmu.ac.uk/learn/microscope.htm) and contains a section for the three major groups of human-pathogenic parasites (Peña-Fernández et al., 2018) [1]. Digitised slides are provided with the functionality of a microscope by using the gadget Zoomify®, and we consider that they can enhance learning, as previous studies reported in the literature have reported similar sensitivity and specificity rates for identification of parasites for both digitised and real slides. The DMU e-Biology’s VM, currently in development, will provide healthy and pathological tissue samples from a range of mammalian tissues and organs. This communication will provide a description of both virtual libraries and the process of developing them. In conjunction, we will use a three-dimensional (3D) super-resolution microscopy, 3D Cell Explorer (Nanolive, Lausanne, Switzerland), to incorporate potential 3D microscopic photographs/short videos of cells to provide students with information about the spatial arrangement and morphologies of cells that are essential for life

Introducing medical parasitology at the University of Makeni, Sierra Leone

The file attached to this record is the author's final peer reviewed version.Capacity building in Sierra Leone (West Africa) is critical to prevent potential future outbreaks similar to the 2013-16 Ebola outbreak that had devastating effects for the country and its poorly developed healthcare system. De Montfort University (DMU) in the United Kingdom (UK), in collaboration with parasitologists from the Spanish Universities of San Pablo CEU and Miguel Hernández de Elche, is leading a project to build the teaching and research capabilities of medical parasitology at the University of Makeni (UniMak, Sierra Leone). This project has two objectives: a) to introduce and enhance the teaching of medical parasitology, both theoretical and practical; and b) to implement and develop parasitology research related to important emerging human parasites such as Cryptosporidium spp. due to their public health significance. Two UniMak academics, hired to help initiate and implement the research part of the project, shared their culturally sensitive public health expertise to broker parasitology research in communities and perform a comprehensive environmental monitoring study for the detection of different emerging human parasites. The presence of targeted parasites are being studied microscopically using different staining techniques, which in turn have allowed UniMak’s academics to learn these techniques to develop new practicals in parasitology. To train UniMak’s academics and develop both parts of our project, a DMU researcher visited UniMak for two weeks in April 2019 and provided a voluntary short training course in basic parasitology, which is currently not taught in any of their programmes, and was attended by 31 students. These sessions covered basic introduction to medical parasitology and life-cycle, pathogenesis, detection, treatment and prevention of: a) coccidian parasites (Cryptosporidium, Cyclospora and Cystoisospora); b) Giardia intestinalis, Entamoeba and free-living amoebas; c) malaria and d) microsporidia. A theoretical session on common staining techniques was also provided. To facilitate the teaching and learning of these parasites, the novel resource DMU e-Parasitology was used, a package developed by the above participating universities and biomedical scientists from the UK National Health Service (NHS): http://parasitology.dmu.ac.uk/ index.htm. Following the two weeks of training, UniMak’s academics performed different curriculum modifications to the undergraduate programme ‘Public Health: Medical Laboratory Sciences’, which includes the introduction of new practicals in parasitology and changes to enhance the content of medical parasitology that will be subjected to examination. Thus, a new voluntary practical on Kinyoun stain for the detection of coccidian parasites was introduced in the final year module of ‘Medical Bacteriology and Parasitology’; eighteen students in pairs processed faecal samples from pigs provided by the Department of Agriculture and Food Security from a nearby farm. Academics at UniMak used the Kinyoun staining unit (available at http://parasitology.dmu.ac.uk/learn/lab/Kinyoun/story_html5.html; [1]) to deliver this practical. Although our project is at a preliminary stage, it has been shown to be effective in promoting the introduction and establishment of medical parasitology at UniMak and could be viewed as a case-study for other universities in low-income countries to promote the United Nations (UN) Sustainable Development Goals (SDGs) and improve public health understanding of infectious diseases

Big Area Additive Manufacturing of High Performance Bonded NdFeB Magnets

Additive manufacturing allows for the production of complex parts with minimum material waste, offering an effective technique for fabricating permanent magnets which frequently involve critical rare earth elements. In this report, we demonstrate a novel method - Big Area Additive Manufacturing (BAAM) - to fabricate isotropic near-net-shape NdFeB bonded magnets with magnetic and mechanical properties comparable or better than those of traditional injection molded magnets. The starting polymer magnet composite pellets consist of 65 vol% isotropic NdFeB powder and 35 vol% polyamide (Nylon-12). The density of the final BAAM magnet product reached 4.8 g/cm3, and the room temperature magnetic properties are: intrinsic coercivity Hci = 688.4 kA/m, remanence Br = 0.51 T, and energy product (BH)max = 43.49 kJ/m3 (5.47 MGOe). In addition, tensile tests performed on four dogbone shaped specimens yielded an average ultimate tensile strength of 6.60 MPa and an average failure strain of 4.18%. Scanning electron microscopy images of the fracture surfaces indicate that the failure is primarily related to the debonding of the magnetic particles from the polymer binder. The present method significantly simplifies manufacturing of near-net-shape bonded magnets, enables efficient use of rare earth elements thus contributing towards enriching the supply of critical materials

Applicability of monthly CDC case studies to improve reflection in biomedical science students.

Background Academics from De Montfort University (DMU, UK) in collaboration with other EU universities, virologists and first responders are developing training for health science students to deal with biological incidents. Initially the training is being tested with final year students enrolled on the BSc Biomedical Science (Hons) and in the BMedSci Medical Science (Hons) degree programmes in 2016/17 at DMU. To improve the limited clinical skills of these students, a series of parasitology case studies have been introduced, where students will need to reflect on their knowledge and search for information from different sources to propose possible diagnoses. Reflection is an essential learning tool for developing aspects such autonomous working, critical and analytical thinking and integration of theory with practice (Quintanilla et al., 2016). Methods A series of teaching sessions (theoretical and practical) has been created related to emergency preparedness and response (Peña-Fernández et al., 2016). Students are provided with different scenarios to develop an intervention programme to protect human health in the aftermath of a biological incident involving different biological agents including emerging parasites. During the theoretical component of the training students are provided with different slides collected from the Laboratory Identification of Parasitic Diseases of Public Health Concern (DPDx) (CDC, 2016). Students, by peer group interaction, provide a possible “diagnosis” for each clinical case based on the clinical features presented and microscopic slides provided. Critical thinking is encouraged. Results Although our results are preliminary and we need to evaluate the students’ feedback, the introduction of clinical case-studies has shown to facilitate the acquisition of some clinical skills, particularly in the biomedical science cohort. This is informed by the high level of students’ interaction during these sessions and the formulation of appropriate questions. Students have also shown some gradual improvement in the resolution of clinical case studies throughout the course. Conclusions Despite the fact that student feedback will not be collected until the end of the course, students have display strong engagement and interest in these workshops through interim module level feedback. A priori, these case-studies have been shown to be effective in facilitating the acquisition of different transversal competences including critical thinking, clinical skills, communication and team work

Resonant Subband Landau Level Coupling in Symmetric Quantum Well

Subband structure and depolarization shifts in an ultra-high mobility GaAs/Al_{0.24}Ga_{0.76}As quantum well are studied using magneto-infrared spectroscopy via resonant subband Landau level coupling. Resonant couplings between the 1st and up to the 4th subbands are identified by well-separated anti-level-crossing split resonance, while the hy-lying subbands were identified by the cyclotron resonance linewidth broadening in the literature. In addition, a forbidden intersubband transition (1st to 3rd) has been observed. With the precise determination of the subband structure, we find that the depolarization shift can be well described by the semiclassical slab plasma model, and the possible origins for the forbidden transition are discussed.Comment: 4 pages, 2 figure

Magnetic filtration of phase separating ferrofluids: From basic concepts to microfluidic device

In this work, we briefly review magnetic separation of ferrofluids composed of large magnetic particles (60 nm of the average size) possessing an induced dipole moment. Such ferrofluids exhibit field-induced phase separation at relatively low particle concentrations (∼0.8 vol%) and magnetic fields (∼10 kA/m). Particle aggregates appearing during the phase separation are extracted from the suspending fluid by magnetic field gradients much easier than individual nanoparticles in the absence of phase separation. Nanoparticle capture by a single magnetized microbead and by multi-collector systems (packed bed of spheres and micro-pillar array) has been studied both experimentally and theoretically. Under flow and magnetic fields, the particle capture efficiency Λ decreases with an increasing Mason number for all considered geometries. This decrease may become stronger for aggregated magnetic particles (Λ∝Ma−1.7) than for individual ones (Λ∝Ma−1) if the shear fields are strong enough to provoke aggregate rupture. These results can be useful for development of new magneto-microfluidic immunoassays based on magnetic nanoparticles offering a much better sensitivity as compared to presently used magnetic microbeads. © 2016 Elsevier B.V

Fluorescent D-amino-acids reveal bi-cellular cell wall modifications important for Bdellovibrio bacteriovorous predation

Modification of essential bacterial peptidoglycan (PG) containing cell walls can lead to antibiotic resistance, for example β-lactam resistance by L,D-transpeptidase activities. Predatory Bdellovibrio bacteriovorus are naturally antibacterial and combat infections by traversing, modifying and finally destroying walls of Gram-negative prey bacteria, modifying their own PG as they grow inside prey. Historically, these multi-enzymatic processes on two similar PG walls have proved challenging to elucidate. Here, with a PG labelling approach utilizing timed pulses of multiple fluorescent D-amino acids (FDAAs), we illuminate dynamic changes that predator and prey walls go through during the different phases of bacteria:bacteria invasion. We show formation of a reinforced circular port-hole in the prey wall; L,D-transpeptidaseBd mediated D-amino acid modifications strengthening prey PG during Bdellovibrio invasion and a zonal mode of predator-elongation. This process is followed by unconventional, multi-point and synchronous septation of the intracellular Bdellovibrio, accommodating odd- and even-numbered progeny formation by non-binary division

First detection of microsporidia in deer faecal samples in England.

Background: Animals infected with human-pathogenic microsporidia (Encephalitozoon spp., Enterocytozoon bieneusi) can release spores into the environment through their faeces representing a public health concern. However, information on their presence in wild animals in the United Kingdom (UK) is very limited despite wildlife living close to densely populated urban areas. Two species of deer can be found in Bradgate Park, a public park in the northwest of Leicester (UK): the red deer and fallow deer. The aim of this study was to determine the presence of human-pathogenic microsporidia in deer as information on their presence in deer is limited in the literature. Materials/methods: A total of 68 deer faecal samples were collected during winter 2016/17; a qualified veterinarian confirmed the source. Fresh faecal smears were immediately prepared and stained using Weber’s modified trichrome stain following previous methodologies. Two microscopists screened the slides for these species. Results: Nine of the 68 faecal samples collected (13.2%) were found to be positive for spores of Encephalitozoon spp. via coprological analysis. These positive results are being confirmed using PCR. These results are in agreement with a pilot study performed by our group in the same park in summer 2016 in which we detected Encephalitozoon spp. in 25%deer faecal samples collected. Conclusions: To our knowledge, this is the first study showing the presence of Encephalitozoon spp. in deer and in an English region. Previous studies have reported spores of microsporidia in deer but for Enterocytozoon bieneusi, in a similar study performed in faeces from sika and red deer in China (Zhao et al., 2014). Our results, although preliminary, could highlight the role of deer as a reservoir and source of environmental contamination for potential zoonotic Encephalitozoon spp. infections. We have also detected Encephalitozoon spp. and Enterocytozoon bieneusi in faecal samples from fox, waterfowl and pigeon collected in the same period but in different parks across Leicester, which could indicate a certain distribution of microsporidia in the Leicester urban environment with different animal species involved in their life cycle. Due to their potential as human pathogens, these reservoirs represent a potential health risk for the Leicester population

Closed-loop magnetic separation of nanoparticles on a packed bed of spheres

In this work, we consider magnetic separation of iron oxide nanoparticles when a nanoparticle suspension (diluted ferrofluid) passes through a closed-loop filter composed of a packed bed of micro-beads magnetized by an externally applied magnetic field. We show that the capture of nanoparticles of a size as small as 60 nm is easily achieved at low-to-moderate magnetic fields (16-32 kA/m) thanks to relatively strong magnetic interactions between them. The key parameter governing the capture process is the Mason number - the ratio of hydrodynamic-to-magnetic forces exerted to nanoparticles. The filter efficiency, Λ, defined through the ratio of the inlet-to-outlet concentration shows a power-law dependency on Mason number, Λ∞Ma-0.83, in the range of 102<Ma<104. The proposed theoretical model allows a correct prediction of the Mason number dependency of the filter efficiency. The obtained results could be of potential interest for water purification systems based on chemical adsorption of micro-pollutants on magnetic nanoparticles, followed by magnetic separation of the nanoparticles. © 2015 AIP Publishing LLC