Objective probability and quantum fuzziness

This paper offers a critique of the Bayesian interpretation of quantum mechanics with particular focus on a paper by Caves, Fuchs, and Schack containing a critique of the "objective preparations view" or OPV. It also aims to carry the discussion beyond the hardened positions of Bayesians and proponents of the OPV. Several claims made by Caves et al. are rebutted, including the claim that different pure states may legitimately be assigned to the same system at the same time, and the claim that the quantum nature of a preparation device cannot legitimately be ignored. Both Bayesians and proponents of the OPV regard the time dependence of a quantum state as the continuous dependence on time of an evolving state of some kind. This leads to a false dilemma: quantum states are either objective states of nature or subjective states of belief. In reality they are neither. The present paper views the aforesaid dependence as a dependence on the time of the measurement to whose possible outcomes the quantum state serves to assign probabilities. This makes it possible to recognize the full implications of the only testable feature of the theory, viz., the probabilities it assigns to measurement outcomes...Comment: 21 pages, no graphics, inspired by "Subjective probability and quantum certainty" (quant-ph/0608190 v2

Autonomic physiological data associated with simulator discomfort

The development of a physiological monitoring capability for the Army's advanced helicopter simulator facility is reported. Additionally, preliminary physiological data is presented. Our objective was to demonstrate the sensitivity of physiological measures in this simulator to self-reported simulator sickness. The data suggested that heart period, hypergastria, and skin conductance level were more sensitive to simulator sickness than were vagal tone and normal electrogastric activity

Effective use of mathematical equations in an online learning environment

Mathematical analysis is an essential tool in the practice of science, technology, engineering, and mathematics, and consequently it is important for students in these subjects to demonstrate effective use of mathematics. In this talk we are interested in supporting the use of mathematical equations in an online learning environment; in particular, we require methods of supporting both the entry and automated marking of mathematical equations, in order to support immediate personalised feedback to the learner

Seminal plasma regulation of the post-coital inflammatory response in the human cervix

In mice and other mammalian species, deposition of semen into the female reproductive tract elicits a local inflammatory response. Whether a comparable response occurs within the human cervix has not previously been studied. The experiments described in this thesis demonstrate, using cervical tissue biopsies taken before and after intercourse, that exposure to semen elicits an infiltration of leukocytes into the cervical tissue of peri-ovulatory women. Immunohistochemical analysis identified macrophages and dendritic cells as the predominant leukocytes recruited into the cervical epithelium and stroma following intercourse. Cytotoxic / suppressor T lymphocytes and memory T cells were also increased. Comparable responses were not detected following condom-protected intercourse. Quantitative real-time PCR was performed on duplicate tissue biopsies to investigate the molecular regulation of this response. Expression of GM-CSF, a potent stimulator of myeloid cell recruitment, was found to increase by 2.5-fold following unprotected intercourse. Trends towards increased IL-6 and IL-8 mRNA were also observed. Condom-protected intercourse did not activate cytokine expression, further suggesting that exposure to semen, as opposed to mechanical trauma, provides the inflammatory stimulus. In an in vitro model using the immortalised Ect-1 cell line, TGFβ was identified as a candidate active seminal factor. All three TGFβ isoforms were capable of mimicking the stimulatory ability of seminal plasma in Ect-1 cells and were comparable in their capacity to stimulate both GM-CSF and IL-6 expression in a dose-responsive manner. The addition of TGFβ isoform-specific neutralising antibodies inhibited seminal plasma-induced increases in these cytokines. However TGFβ was unable to stimulate IL-8 production. Addition of IFNƴ was found to strongly inhibit TGFβ-stimulated GM-CSF production, and 19-0H PGE₁ was found to increase IL-6 and IL-8, but not GM-CSF production. Responses to seminal plasma constituents were almost exactly replicated in primary cultures of human ectocervical cells. These results identify TGFβ as the major active constituent in human seminal plasma and indicate that other seminal agents, 19-0H PGE₁ and IFNƴ, interact with TGFβ to differentially regulate cervical cytokine expression. Finally, whether human seminal plasma cytokine content was associated with fertility in men was examined. No relationship between seminal plasma TGFβ₁, TGFβ₂, TGFβ₃, IL-8 or bacterial endotoxin content and fertility status was observed. However, there was an increased likelihood of high IFNƴ content in the male partners of couples experiencing infertility, most notable in recurrent miscarriage. The discriminating value of IFNƴ was increased when evaluated as a ratio of total TGFβ content. Inflammatory changes after exposure of the female reproductive tract to seminal plasma are implicated in 'conditioning' the maternal immune response, to facilitate successful embryo implantation and pregnancy. The studies described in this thesis provide a mechanistic basis for the observations linking exposure to semen with pregnancy success in humans and have expanded our knowledge of the cellular and molecular events that occur within the female reproductive tract following intercourse. Seminal plasma can therefore no longer be thought of as merely a transport medium for spermatozoa, rather as a means for communication between the male and female reproductive tissues, potentially required for optimal pregnancy success.Thesis (Ph.D.) -- University of Adelaide, Dept. of Obstetrics and Gynaecology, 200

A demonstration of motion base design alternatives for the National Advanced Driving Simulator

A demonstration of the capability of NASA's Vertical Motion Simulator to simulate two alternative motion base designs for the National Advanced Driving simulator (NADS) is reported. The VMS is located at ARC. The motion base conditions used in this demonstration were as follows: (1) a large translational motion base; and (2) a motion base design with limited translational capability. The latter had translational capability representative of a typical synergistic motion platform. These alternatives were selected to test the prediction that large amplitude translational motion would result in a lower incidence or severity of simulator induced sickness (SIS) than would a limited translational motion base. A total of 10 drivers performed two tasks, slaloms and quick-stops, using each of the motion bases. Physiological, objective, and subjective measures were collected. No reliable differences in SIS between the motion base conditions was found in this demonstration. However, in light of the cost considerations and engineering challenges associated with implementing a large translation motion base, performance of a formal study is recommended

A one-piece 3D printed flexure translation stage for open-source microscopy.

Open source hardware has the potential to revolutionise the way we build scientific instruments; with the advent of readily available 3D printers, mechanical designs can now be shared, improved, and replicated faster and more easily than ever before. However, printed parts are typically plastic and often perform poorly compared to traditionally machined mechanisms. We have overcome many of the limitations of 3D printed mechanisms by exploiting the compliance of the plastic to produce a monolithic 3D printed flexure translation stage, capable of sub-micron-scale motion over a range of 8 × 8 × 4 mm. This requires minimal post-print clean-up and can be automated with readily available stepper motors. The resulting plastic composite structure is very stiff and exhibits remarkably low drift, moving less than 20 μm over the course of a week, without temperature stabilisation. This enables us to construct a miniature microscope with excellent mechanical stability, perfect for time-lapse measurements in situ in an incubator or fume hood. The ease of manufacture lends itself to use in containment facilities where disposability is advantageous and to experiments requiring many microscopes in parallel. High performance mechanisms based on printed flexures need not be limited to microscopy, and we anticipate their use in other devices both within the laboratory and beyond.We would like to thank Paula Rudall (Jodrell Laboratory, Royal Botanic Gardens, Kew, UK) for preparing the Pollia condensata samples. RWB was supported by Research Fellowships from Queens’ College, Cambridge and the Royal Commission for the Exhibition of 1851, and partial support was provided by EPSRC EP/L027151/1, the University Teaching and Learning Innovation Fund and the SynBioFund initiative.This is the final version of the article. It first appeared from AIP Publishing via http://dx.doi.org/10.1063/1.4941068 Data supporting this publication is available at http://www.repository.cam.ac.uk/handle/1810/253294. Design files and assembly instructions are available at http://docubricks.com/projects/ openflexure-microscope

Polarisation vision: overcoming challenges of working with a property of light we barely see.

In recent years, the study of polarisation vision in animals has seen numerous breakthroughs, not just in terms of what is known about the function of this sensory ability, but also in the experimental methods by which polarisation can be controlled, presented and measured. Once thought to be limited to only a few animal species, polarisation sensitivity is now known to be widespread across many taxonomic groups, and advances in experimental techniques are, in part, responsible for these discoveries. Nevertheless, its study remains challenging, perhaps because of our own poor sensitivity to the polarisation of light, but equally as a result of the slow spread of new practices and methodological innovations within the field. In this review, we introduce the most important steps in designing and calibrating polarised stimuli, within the broader context of areas of current research and the applications of new techniques to key questions. Our aim is to provide a constructive guide to help researchers, particularly those with no background in the physics of polarisation, to design robust experiments that are free from confounding factors

Accurate neonatal heart rate monitoring using a new wireless, cap mounted device

© 2020 The Authors. Acta Paediatrica published by John Wiley & Sons Ltd on behalf of Foundation Acta Paediatrica Aim: A device for newborn heart rate (HR) monitoring at birth that is compatible with delayed cord clamping and minimises hypothermia risk could have advantages over current approaches. We evaluated a wireless, cap mounted device (fhPPG) for monitoring neonatal HR. Methods: A total of 52 infants on the neonatal intensive care unit (NICU) and immediately following birth by elective caesarean section (ECS) were recruited. HR was monitored by electrocardiogram (ECG), pulse oximetry (PO) and the fhPPG device. Success rate, accuracy and time to output HR were compared with ECG as the gold standard. Standardised simulated data assessed the fhPPG algorithm accuracy. Results: Compared to ECG HR, the median bias (and 95% limits of agreement) for the NICU was fhPPG −0.6 (−5.6, 4.9) vs PO −0.3 (−6.3, 6.2) bpm, and ECS phase fhPPG −0.5 (−8.7, 7.7) vs PO −0.1 (−7.6, 7.1) bpm. In both settings, fhPPG and PO correlated with paired ECG HRs (both R2=0.89). The fhPPG HR algorithm during simulations demonstrated a near-linear correlation (n=1266, R2=0.99). Conclusion: Monitoring infants in the NICU and following ECS using a wireless, cap mounted device provides accurate HR measurements. This alternative approach could confer advantages compared with current methods of HR assessment and warrants further evaluation at birth

Is dissection the only way to learn anatomy? Thoughts from students at a non-dissecting based medical school.

Anatomical teaching has been centred around dissection for centuries. Generations of doctors have been initiated into the medical profession by cutting into their first cadavers. With the number of donor cadavers available decreasing and medical student numbers increasing, the emphasis placed on dissection has changed dramatically over the past 15 years. However, a solid appreciation of human anatomy is still a necessary part of understanding pathology and treatments. Therefore in light of these changes we ask, is dissection the only option? Or are there other options which students can undertake to develop anatomical knowledge?This article is freely available via Open Access. Click on the 'Additional Link' above to access the full-text from the publisher's site.Published (Open Access