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"Perhaps Irrelevant". The Iconography of Tycho Brahe's Small Gilt Brass Quadrant.
When Tycho Brahe published a description of his astronomical instruments in 1598 as part of a strategy to procure royal patronage, it was not with one of his grander, precision measurement tools that he opened his account, but rather a small brass quadrant with limited observational utility. The defining feature of this instrument was seemingly a small emblematic image inscribed within the arc of the quadrant. Through this symbolic motif Tycho conveyed a moralising message about the relative worth of astronomy. Considering a range of visual productions that may have influenced his iconography, the present paper situates the quadrant within the broader context of Renaissance visual culture and examines the significance of the quadrant in Tycho's wider instrument collection.Emma Perkins’ research was made possible through the generous support of an AHRC doctoral award.This is the accepted manuscript. The final version is available from Brill at http://booksandjournals.brillonline.com/content/journals/10.1163/18253911-03001002
Building Brighter Futures
A large mural of two students reading on top of a pile of books while a large eagle is fixated on the right side. There is a small child kneeling in front of what looks like a Roman pillar. This was created by Emma Perkins with help from Alan Perkins and her students in 2003.https://scholarworks.moreheadstate.edu/university_art_collection/1128/thumbnail.jp
Investigating the modulation of neonatal rat facial motoneurone excitability by monoamine neurotransmitters: Postsynaptic mechanisms and presynaptic modulation of glutamate release.
The activity patterns of 5-HT-releasing neurons can be positively correlated with
behavioural state and motor function and the central 5-HT system modulates motor
activity at the cellular level. The rat facial motor nuclei are densely innervated by 5-
HT releasing afferents and 5-HT-mediated modulation of ion channels on the soma
and dendrites can markedly influence the excitability of facial motoneurones and
their integration of excitatory postsynaptic potentials (EPSPs). 5-HT facilitates facial
motoneuron excitation by inhibiting a ‘leak’ potassium (K+) conductance (gK+
Leak)
and enhancing the hyperpolarisation-activated cation current, Ih. These actions of 5-
HT have been confirmed using whole-cell voltage-clamp recordings from visually
identified facial motoneurones in an acute brainstem slice preparation.
Pharmacological approaches have been used to identify the receptors which mediate
the actions of 5-HT in facial motoneurones. The inhibition of gK+
Leak by 5-HT can
be blocked by the 5-HT2A receptor antagonist, R96544 (0.3 – 1μM) and the
enhancement of Ih by 5-HT is sensitive to the 5-HT7 receptor antagonist, SB269970
(0.3 – 10 μM).
Noradrenaline was also found to inhibit gK+
Leak, via activation of a1 adrenoceptors,
and the molecular identity of the amine-sensitive ‘leak’ K+ channels has been
investigated. TASK-1 and TASK-3 are pH-sensitive two-pore domain K+ channels
that can be modulated by amines and provide ‘leak’ K+ conductances in several
central neurones. The mRNAs for these channels have been reported to be present in
the rat facial motor nucleus. The gK+
Leak in facial motoneurones is sensitive to
changes in external pH and has a pK of ~7.1, which is intermediate between the
v
values for homomeric TASK-1 and TASK-3 channels (7.5 and 6.8 respectively).
The TASK-1 selective inhibitor anandamide (10 μM), its stable analogue
methanandamide (10 μM), the TASK-3 selective inhibitor ruthenium red (10 μM)
and Zn2+ (100-300 μM) all failed to alter the actions of noradrenaline or changing
external pH. These findings argue against principal contributions to gKLeak by
homomeric TASK-1 or TASK-3 channels. Isoflurane, a volatile anaesthetic that
enhances heteromeric TASK-1 / TASK-3 currents, potentiated gKLeak supporting a
predominant role for heterodimeric TASK-1 / TASK-3 channels in the gKLeak in
facial motoneurones.
Evoked fast excitatory synaptic transmission in the facial motor nucleus has been
characterised and NMDA and non-NMDA receptor-mediated components of this
synaptic transmission have been identified. Through a combination of analysis of the
paired pulse ratio, rate of failure to generate a response and the frequency and
amplitude of miniature excitatory postsynaptic currents (mEPSCs) this study
provides evidence to suggest that glutamate release from pre-synaptic terminals in
the facial motor nucleus is depressed by 5-HT. This action of 5-HT is mediated by
activation of presynaptic 5-HT1B receptors as this effect is mimicked by the 5-HT1B
receptor agonist, CP93129 (10 μM) and can be blocked by the 5-HT1B receptor
antagonist, isamoltane (1 μM).
These studies indicate that the modulation of synaptic integration in the facial motor
nucleus involves activation of distinct pre- and post-synaptic 5-HT receptor subtypes.
These findings not only increase our understanding of the cellular mechanisms for
vi
the 5-HT modulation of motor activity but may also be relevant to the role of 5-HT
in the control of other central neurones
Nasal fentanyl alone plus buccal midazolam: an open-label, randomised, controlled feasibility study in the dying
Introduction: Many patients want to stay at home to die. They invariably become unable to take oral medication during their terminal phase. Symptoms are usually controlled by subcutaneous medications. There have been no studies on nasal fentanyl (NF) or buccal midazolam (BM) to control symptoms in the dying.Objective: To establish how best to conduct a definitive, randomised controlled trial (RCT) to determine whether NF and BM administered by families, for patients dying at home, lead to faster and better symptom control and fewer community nursing visits than standard breakthrough medication by healthcare professionals.Methods: This open-label mixed-method feasibility RCT compared the efficacy of NF and BM by family members to standard breakthrough medication by nurses for the terminally ill in a specialist palliative care unit. Partway through the study, a third observational arm was introduced where BM alone was used. The primary outcomes were whether recruitment and randomisation were possible, assessment of withdrawal and drop-out, and whether the methods were acceptable and appropriate.Results: Administration of NF and BM was acceptable to patients and families. Both were well tolerated. We were unable to obtain quality of life data consistently but did get time period data for dose-controlled symptoms.Conclusions: Study participation in a hospice population of the dying was acceptable. The results will help guide future community study planning
Commissioning through competition and cooperation in the English NHS under the Health and Social Care Act 2012: evidence from a qualitative study of four clinical commissioning groups.
OBJECTIVE: The Health and Social Care Act 2012 ('HSCA 2012') introduced a new, statutory, form of regulation of competition into the National Health Service (NHS), while at the same time recognising that cooperation was necessary. NHS England's policy document, The Five Year Forward View ('5YFV') of 2014 placed less emphasis on competition without altering the legislation. We explored how commissioners and providers understand the complex regulatory framework, and how they behave in relation to competition and cooperation. DESIGN: We carried out detailed case studies in four clinical commissioning groups, using interviews and documentary analysis to explore the commissioners' and providers' understanding and experience of competition and cooperation. SETTING/PARTICIPANTS: We conducted 42 interviews with senior managers in commissioning organisations and senior managers in NHS and independent provider organisations (acute and community services). RESULTS: Neither commissioners nor providers fully understand the regulatory regime in respect of competition in the NHS, and have not found that the regulatory authorities have provided adequate guidance. Despite the HSCA 2012 promoting competition, commissioners chose mainly to use collaborative strategies to effect major service reconfigurations, which is endorsed as a suitable approach by providers. Nevertheless, commissioners are using competitive tendering in respect of more peripheral services in order to improve quality of care and value for money. CONCLUSIONS: Commissioners regard the use of competition and cooperation as appropriate in the NHS currently, although collaborative strategies appear more helpful in respect of large-scale changes. However, the current regulatory framework contained in the HSCA 2012, particularly since the publication of the 5YFV, is not clear. Better guidance should be issued by the regulatory authorities
On the Widom-Rowlinson occupancy fraction in regular graphs
We consider the Widom-Rowlinson model of two types of interacting particles
on d-regular graphs. We prove a tight upper bound on the occupancy fraction,
the expected fraction of vertices occupied by a particle under a random
configuration from the model. The upper bound is achieved uniquely by unions of
complete graphs on d+1 vertices, 's. As a corollary we find that
also maximises the normalised partition function of the
Widom-Rowlinson model over the class of d-regular graphs. A special case of
this shows that the normalised number of homomorphisms from any d-regular graph
to the graph , a path on three vertices with a loop on each vertex,
is maximised by . This proves a conjecture of Galvin
Playful mapping in the digital age:The Playful Mapping Collective
From Mah-Jong, to the introduction of Prussian war-games, through to the emergence of location-based play: maps and play share a long and diverse history. This monograph shows how mapping and playing unfold in the digital age, when the relations between these apparently separate tropes are increasingly woven together. Fluid networks of interaction have encouraged a proliferation of hybrid forms of mapping and playing and a rich plethora of contemporary case-studies, ranging from fieldwork, golf, activism and automotive navigation, to pervasive and desktop-based games evidences this trend. Examining these cases shows how mapping and playing can form productive synergies, but also encourages new ways of being, knowing and shaping our everyday lives. The chapters in this book explore how play can be more than just an object or practice, and instead focus on its potential as a method for understanding maps and spatiality. They show how playing and mapping can be liberating, dangerous, subversive and performative
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