366 research outputs found
Sensory and motor neuronal networks of the spinal cord
No full textThis body of work is focused upon neuronal networks of the spinal cord which are
involved in processing of sensory information and generation of motor output. It
includes a detailed account of the synaptic organisation, target neurons and
neurotransmitter content of central terminals of various classes of cutaneous and
proprioceptive primary afferent axons. It shows that presynaptic boutons at
axoaxonic synapses, which regulate primary afferent transmission, contain GABA
but that other transmitters such as glycine, neuropeptide Y and acetylcholine may
be co-localised in these structures. The principal conclusion is that certain subtypes
of presynaptic inhibitory interneurons target the terminals of specific types of primary
afferent fibres but the majority of these neurons do not from 'pure' presynaptic
inhibitory systems because many of them also mediate postsynaptic inhibition. A
further series of investigations provides a detailed analysis of the organisation of
monoaminergic axon terminals and the receptors that they act upon. This work
supports the existence of two parallel modes of action for monoamines in the cord; a
diffuse (non-synaptic or paracrine) system and a specific system which acts through
direct synaptic actions on particular target neurons. Serotonin, for example, acts as
a general modulator but also regulates transmission in some pathways selectively.
Amongst the cells that are targeted selectively, are interneurons in reflex pathways
and a class of projection neuron which receives monosynaptic input from
nociceptive primary afferent axons. More recently, the focus has been on the
organization and neurochemical properties of spinal interneurons. Until recently,
there were few satisfactory classifications of spinal interneurons and the relationship
between functional and structural properties of such cells was unclear. A detailed
analysis of interneurons has shown that there is a clear relationship between the
action of a given interneuron (i.e. whether it is inhibitory or excitatory), its axonal
projections and the classes of cell that it targets. In conclusion, the work reported in
this thesis is an attempt to elucidate neuronal circuits which underlie sensory and
motor processes in the spinal cord by applying modern functional anatomical
approaches.SELECTED REVIEW ARTICLES (PEER REVIEWED):
1. Morris, R., Cheunsuang, O., Stewart, A. and Maxwell, D. (2004) Spinal dorsal horn neurone
targets for nociceptive primary afferents: do single neurone morphological characteristics
suggest how nociceptive information is processed at the spinal level. Brain Res. Rev. 46, 173-
190. (Review article written as co-author with Dr. Richard Morris; contains some unpublished
data from all 4 authors) ||
2. Jankowska, E., Maxwell, D.J. and Bannatyne, B.A. (2007) On coupling and decoupling of
spinal interneuronal networks Arch. Ital. Biol. 145: 235-250, 2007 (Review article written
jointly by E. Jankowska, B.A. Bannatyne and DJM: summarises some of our major findings).SELECTED PEER REVIEWED ARTICLES:
1. Maxwell, D.J. Bannatyne, B.A., Brown, A.G. and Fyffe, R.E.W. (1982) Ultrastructure of
physiologically identified hair follicle afferent fibres in the cat spinal cord. Journal of
Neurocytology 11, 571-582. (Author; performed bulk of experimental work reported). ||
2. Maxwell, D.J., Leranth, Cs. and Verhofstad, A.A.J. (1983) fine structure of serotonin
containing axons in the marginal zone of the rat spinal cord. Brain Research 266, 253-260. ||
(Author; initiated and performed bulk of experimental work reported).
3. Maxwell, D.J., Fyffe, R.E.W. and Rethelyi, M. (1983) Morphological properties of
physiologically characterized lamina III neurons in the cat spinal cord. Neuroscience 10, 1-22.
(Author; initiated and performed bulk of experimental work reported). ||
4. Maxwell, D.J., Fyffe, R.E.W. and Brown, A.G. (1984) Fine structure of normal and
degenerating primary afferent boutons associated with characterized spinocervical tract
neurones in the cat. Neuroscience 12, 151-163. (Author; initiated and performed bulk of
experimental work reported). ||
5. Maxwell, D.J. and Bannatyne, B.A. (1983) Ultrastructure of muscle spindle afferent
terminations in lamina VI of the cat spinal cord. Brain Research 288, 297-301. (Author;
initiated and performed bulk of experimental work reported). ||
6. Maxwell, D.J., Bannatyne, B.A., Fyffe, R.E.W. and Brown, A.G. (1984) Fine structure of
primary afferent terminations projecting from rapidly adapting mechanoreceptors of the toe
and foot pads of the cat. Quarterly Journal of Experimental Physiology 69, 381-392. (Author;
initiated study and performed bulk of experimental work reported jointly with B.A. Banntyne). ||
7. Bannatyne, B.A., Maxwell, D.J., Fyffe, R.E.W. and Brown, A.G. (1984) Fine structure of
primary afferent terminals of slowly adapting cutaneous receptors in the cat. Quarterly Journal
ofExperimental Physiology 69, 547-557. (Author; initiated study and performed bulk of
experimental work reported jointly with B.A. Banntyne).
2 ||
8. Maxwell, D.J., Koerber, H.R. and Bannatyne, B.A. (1985) Light and electron microscopy of
contacts between primary afferent fibres and neurons with axons ascending the dorsal columns
of the feline spinal cord. Neuroscience 16, 375-394. (Author; initiated and performed bulk of
experimental work reported). ||
9. Maxwell, D.J. and Koerber, H.R. (1986) Fine structure of collateral axons originating from
feline spinocervical tract neurons. Brain Research 363, 199-203. (Author; initiated and
performed bulk of experimental work reported).
10.Maxwell, D.J., Christie, W.M. and Somogyi, P. (1989) Synaptic connections of GABAcontaining boutons in the lateral cervical nucleus of the cat: an ultrastructural study employing
pre- and post-embedding immunocytochemical methods. Neuroscience 33, 169-184.
(Author; initiated and performed bulk of experimental work reported). ||
II .Maxwell, D.J., Christie, W.M., Ottersen, O.P. and Storm-Mathisen, J. (1990) Terminals of
group la primary afferent fibres in Clarke's column are enriched with L-glutamate-like
immunoreactivity. Brain Research 510, 346-350. (Author; initiated and performed bulk of
experimental work reported). ||
12.Maxwell, D.J., Christie, W.M., Short, A.D., Storm-Mathisen, J. and Ottersen, O.P. (1990)
Central boutons of glomeruli are enriched with L-glutamate-like immunoreactivity in the spinal
cord of the cat. Neuroscience 36, 83-104. (Author; initiated and performed bulk of
experimental work reported). ||
13.Maxwell, D.J., Christie, W.M., Short, A.D. and Brown, A.G. (1990) Direct observations of
synapses between GABA- immunoreactive boutons and muscle afferent terminals in lamina VI
of the cat's spinal cord. Brain Research 530, 215-222. (Author; initiated and performed bulk of
experimental work reported). ||
14.Maxwell, D.J., Christie, W.M., Short, A.D. and Brown, A.G. (1991) Direct observations of
synapses between GABA- immunoreactive boutons and identified spinocervical tract neurons
in the cat's spinal cord. J.Comp. Neurol. 307: 375-392. (Author; initiated and performed bulk
of experimental work reported). ||
15.Doyle, C.A. and Maxwell, D.J. (1991) Catecholaminergic innervation of the spinal dorsal
horn: a correlated light and electron microscopic analysis of tyrosine hydroxylase
immunoreactive fibres in the cat. Neuroscience, 45, 161-176. (Co-author; initiated and
supervised experimental work reported). ||
16.Doyle, C.A. and Maxwell, D.J. (1991) Ultrastructural analysis of noradrenergic nerve
terminals in the cat lumbosacral spinal dorsal horn: a dopamine-B-hydroxylase
immunocytochemical study. Brain Research 563, 329-333. (Co-author; initiated and supervised
experimental work reported). ||
17.Todd, A.J., Maxwell. D.J. and Brown, A.G. (1991) Relationships between hair-follicle afferent
axons and glycine-immunoreactive profiles in cat dorsal horn. Brain Research 564,132-137.
(Co-author; collaborative study with A. Todd). ||
18.Maxwell, D.J., Christie, W.M., Brown, A.G., Ottersen, O.P. and Storm-Mathisen, J. (1992)
Direct observations of synapses between L-glutamate-immunoreactive boutons and identified
spinocervical tract neurones in the spinal cord of the cat. J. Comp. Neurol. 326, 485-500.
(Author; initiated and performed bulk of experimental work reported). ||
19.Doyle, C.A. and Maxwell, D.J. (1993) Direct catecholaminergic innervation of postsynaptic
dorsal column neurons in the cat spinal cord. J. Comp. Neurol. 331, 434-444. (Co-author;
initiated and supervised experimental work reported). ||
20.Doyle, C.A. and Maxwell, D.J. (1993) Neuropeptide Y- immunoreactive terminals form axo¬
axonic synaptic arrangements in the substantia gelatinosa (lamina II) of the cat spinal dorsal
horn. Brain Research 603, 157-161. (Co-author; initiated and supervised experimental work
reported). ||
21.Maxwell, D.J., Christie, W.M., Brown, A.G., Ottersen, O.P. and Storm-Mathisen, J. (1993)
Identified hair follicle afferent boutons in the spinal cord of the cat are enriched with Lglutamate-like immunoreactivity. Brain Research 606, 156-161. (Author; initiated and
performed bulk of experimental work reported). ||
22.Doyle, C.A. and Maxwell, D.J. (1994) Light- and electron-microscopic analysis of
neuropeptide Y-immunoreactive profiles in the cat spinal dorsal horn. Neuroscience 61, 107-
121. (Co-author; initiated and supervised experimental work reported). ||
23.Doyle, C.A. and Maxwell, D.J. (1994) Catecholaminergic innervation of the lateral cervical
nucleus: a correlated light and electron microscopic analysis of tyrosine hydroxylaseimmunoreactive axons in the cat. Neuroscience 61, 381-389. (Co-author; initiated and
supervised experimental work reported). ||
24.Maxwell, D.J., Ottersen, O.P. and Storm-Mathisen, J. (1995) Synaptic organization of
excitatory and inhibitory boutons associated with spinal neurons which project through the
dorsal columns of the cat. Brain Research 676, 103-112. (Author; initiated and performed bulk
of experimental work reported). ||
25.Jankowska, E., Maxwell, D.J., Dolk, S., Krutki, P. Belichenko, P.V. and Dahlstrom, A. (1995)
Contacts between serotoninergic fibres and dorsal horn spinocerebellar tract neurones in the cat
and rat; a confocal microscopic study. Neuroscience, 67,477-487. (Co-author; collaborative
study with E. Jankowska. Performed much of experimental work reported). ||
26.Maxwell, D.J., Todd,A.J. and Kerr, R. (1995) Colocalization of glycine and GABA in
synapses on spinomedullary neurons. Brain Research 690, 127-132. (Author; initiated and
performed bulk of experimental work reported). ||
27.Maxwell, D.J. and Jankowska, E. (1996) Synaptic relations between serotonin-immunoreactive
axons and dorsal horn spinocerebellar tract cells in the cat spinal cord. Neuroscience, 70, 247-
253. (Author; collaborative study with E. Jankowska. initiated and performed morphological
aspects of experimental work reported). ||
28.McGonigle, D.J., Maxwell, D.J., Shehab, S.A.S. and Kerr,R. (1996) Evidence for the presence
of neurokinin-1 receptors on dorsal horn spinocerebellar tract cells in the rat. Brain Research,
742, 1-9. (Author; initiated, supervised and performed experimental work reported). ||
29.Maxwell, L. Maxwell. D.J., Nielson, M. and Kerr. R. (1996) A confocal microscopic survey
of serotoninergic axons in the lumbar spinal cord of the rat: colocalization with glutamate
decarboxylase and neuropeptides. Neuroscience 75: 471-480(Author; initiated, supervised and
performed experimental work reported). ||
30.Maxwell, D.J., Kerr, R., Jankowska, E. and Riddell, J.S. (1997) Synaptic connections of dorsal
horn group II interneurons: synapses formed with the interneurons and by their axon
collaterals. J.Comp. Neurol. 380: 51-69 (Author; collaborative study with E. Jankowska.
initiated and performed morphological aspects of experimental work reported). ||
31.Patel, R., Kerr, R. and Maxwell, D.J. (1997) Absence of co-localized glutamic acid
decarboxylase and neuropeptides in noradrenergic axons of the rat spinal cord. Brain Res. 749:
164-169. (Author; initiated, supervised and performed experimental work reported). ||
32.Jankowska E., Maxwell, D.J. Dolk, S. and Dahlstrom, A. (1997) A confocal and electron
microscopic study of contacts between 5-HT fibres and feline dorsal horn interneurons in
pathways from muscle afferents J.Comp. Neurol. 387, 430-438 (Co-author; collaborative study
with E. Jankowska. initiated and performed morphological aspects of experimental work
reported). ||
33.Pollock, R., Kerr, R. and Maxwell. D.J. (1997) An immunocyochemical investigation ofthe
relationship between substance P and the neurokinin-1 receptor in the lateral horn of the rat
thoracic spinal cord. Brain Res. 777, 22-30 (Author; initiated, supervised and performed
experimental work reported).
34.Spike, R.C., Kerr, R., Maxwell. D.J. and Todd, A.J. (1998) GluRl and GluR2/3 subunits of the
AMPA-type glutamate receptor are associated with particular types of neuron in laminae I-III
of the spinal dorsal horn of the rat, Eur. J. Neurosci. 10,324-333. (Co-author; collaborative
study with A. Todd. Performed some aspects of experimental work reported). ||
35.Welton J., Stewart W., Kerr R. and Maxwell D.J., (1999) Differential expression of the
muscarinic m2 acetylcholine receptor by small and large motoneurons of the rat spinal cord.
Brain Reserarch 817, 215-219 (Author; initiated, supervised and performed experimental work
reported). ||
36.Maxwell D.J. and Riddell J.S. (1999) Axoaxonic synapses on terminals of group II muscle
afferent axons in the spinal cord of the cat. Eur. J. Neurosci. 11, 2151-2159 (Author; initiated
and performed bulk of experimental work reported) ||
37.Maxwell, D.J., Riddell J.S. and Jankowska, E. (2000) Serotoninergic and noradrenergic axonal
contacts associated with premotor interneurons in spinal pathways from group II muscle
afferents. Eur. J. Neurosci .12,1271-1280. (Author; collaborative study with E. Jankowska.
initiated and performed morphological aspects of experimental work reported). ||
38.Gladden, M.H., Maxwell, D.J., Sahal, A. and Jankowska, E. (2000) Coupling between
serotoninergic and noradrenergic neurones and gamma motoneurones in the cat J.Physiol 527,
213-223.. (Co-author; collaborative study with E. Jankowska. Performed morphological
aspects of experimental work reported). ||
39.Stewart, W. and Maxwell, D.J. (2000) Morphological evidence for selective modulation by
serotonin of a sub-population of dorsal horn cells which possess the neurokinin-1 receptor.
Eur. J. Neurosci. 12, 4583-4588. (Co-author; initiated and supervised experimental work
reported). ||
40.Hammar, I. and Maxwell, D.J. (2002) Serotoninergic and Noradrenergic axons make contacts
with neurons of the ventral spinocerebellar tract in the cat. J. Comp. Neurol. 443, 310-319.
(Co-author; initiated, supervised and performed aspects of experimental work reported). ||
41.Cheunsuang, O., Maxwell, D.J. and Morris, R., (2002) Spinal lamina I neurones which express
neurokinin 1 receptors: Elecctrophysiological properties, responses to primary afferent
stimulation and effects of a selective p-opioid receptor agonist. Neuroscience. Ill, 423-434.
(Co-author; collaborative study with R. Morris. Performed morphological aspects of
experimental work reported). ||
42.0lave, M.J. Puri, N. Kerr, R. and Maxwell, D.J. (2002) Myelinated and unmyelinated primary
afferent axons form contacts with cholinergic interneurons in the spinal dorsal horn. Exp. Brain
Res. 145: 448-456. (Author; initiated, supervised and performed aspects experimental work
reported). ||
43.Sutherland, F.I., Bannatyne, B.A., Kerr, R., Riddell, J.S. and. Maxwell,D.J. (2002)
Inhibitory amino acid transmitters associated with axons in presynaptic apposition to cutaneous
primary afferent axons in the cat spinal cord. J. Comp. Neurol. 452: 154-162. (Author;
initiated, supervised and performed aspects experimental work reported). ||
44.0lave, M.J. and Maxwell. D.J. (2002) An investigation of neurons that possess the a2cadrenergic receptor in the rat dorsal horn. Neuroscience, 115, 31-40. (Co-author; initiated and
supervised experimental work reported). ||
45.Todd, A.J., Hughes, D.I.. Polgar, E., Nagy, G.G., Mackie, M., Ottersen, O.P. and Maxwell,
D.J. (2003) The expression of vesicular glutamate transporters VGLUT1 and VGLUT2 in
neurochemically-defined axonal populations in the rat spinal cord with emphasis on the dorsal
horn. Eur. J. Neuroscience. 17, 13-27. (Co-author; supervised aspects of experimental work
reported). ||
46.Maxwell, D. J., Kerr, R., Rashid S. and Anderson E. (2003) Characterisation of axon terminals
in the rat dorsal horn that are immunoreactive for serotonin 5-HT3A receptor subunits. Exp.
Brain Res. 149, 114-124. (Author; initiated, supervised and performed aspects experimental
work reported). ||
47. Olave, M.J. and Maxwell, D.J. (2003) Axon terminals possessing the a2c-adrenergic receptor
in the rat dorsal horn are predominantly excitatory. Brain Res. 965, 269-273. (Co-author;
initiated and supervised experimental work reported). ||
48.Polgar, E., Hughes, D.I., Riddell, J.S., Maxwell, D.J., Puskar, Z. and Todd, A.J. (2003)
Selective loss ofGABAergic or glycinergic is not necessary for the development of thermal
hyperalgesia in the chronic constriction model of neuropathic pain. Pain. 104, 299-239. (Co-author; collaborative study with A. Todd. Supervised some aspects of experimental work
reported). ||
49.Stewart, W. and Maxwell, D.J. (2003) Distribution and organisation of dorsal horn neuronal
cell bodies that possess the muscarinic m2 acetylcholine receptor. Neuroscience 119, 121-135.
(Co-author; initiated and supervised experimental work reported). ||
50.Mackie. M., Hughes, D.I., Maxwell, D.J., Tillakaratine, N.J.K. and Todd, A.J. (2003)
Distribution and colocalisation of glutamate decarboxylase isoforms in the rat spinal cord.
Neuroscience 119, 461-472. (Co-author; collaborative study with A. Todd. Supervised and
performed some aspects of experimental work reported). ||
51 .Olave, M.J. and Maxwell, D.J. (2003) Neurokinin-1 projection cells in the rat dorsal horn
receive synaptic contacts from axons that possess a.2c-adrenergic receptors J. Neurosci. 23,
6837-6846. (Co-author; initiated and supervised experimental work reported). ||
52.Bannatyne, B.A., Edgley, S.A., Hammar, I., Jankowska, E. and Maxwell D.J. (2003) Networks
of inhibitory and excitatory commissural interneurons mediating crossed reticulospinal
actions. Eur. J. Neurosci. 18, 2273-2284. (Author; collaborative study with E. Jankowska.
initiated and performed morphological aspects of experimental work reported). ||
53.Hammar, I., Bannatyne, B.A. Maxwell, D.J., Edgley, S. A. and Jankowska, E. (2004) The
actions of monoamines and distribution of noradrenergic and serotoninergic contacts on
different subpopulations of commissural interneurons in the cat spinal cord. Eur. J. Neurosci.
19, 1305-1316. (Co-author; collaborative study with E. Jankowska. Performed and supervised
morphological aspects of experimental work reported). ||
54.Olave, M.J. and Maxwell, D.J. (2004) Axon terminals possessing a2c-adrenergic receptors
densely innervate , neurons in the rat lateral spinal nucleus which respond to noxious
stimulation. Neuroscience 126, 391-403 (Co-author; initiated and supervised experimental
work reported)
55.Dougherty, K.J. Bannatyne, B.A., Jankowska, E., Krutki, P. and Maxwell D.J. (2005)
Membrane receptors involved in Modulation of responses of spinal dorsal horn interneurons
evoked by feline group II muscle afferents. J. Neurosci. 25, 584-593. (Co-author; collaborative
study with E. Jankowska. Supervised morphological aspects of experimental work reported). ||
56.Conte, D., Legg, E. D., McCourt, A. C., Silajdzic E.,, Nagy, G. G. and Maxwell. D.J. (2005)
Transmitter content, origins and connections of axons in the spinal cord that possess 5-HT3
receptors. Neuroscience, 134, 165-173. (Author; initiated, supervised and performed aspects
experimental work reported). ||
57.Wilson JM, Hartley R, Maxwell DJ, Todd AJ, Lieberam I, Kaltschmidt JA, Yoshida Y, Jessell
TM, Brownstone RM (2005) Conditional rhythmicity of ventral spinal interneurons defined by
expression of the Hb9 homeodomain protein. J Neurosci 25: 5710-5719 (Co-author;
collaborative study with R. Brownstone, A. Todd and T. Jessell. Performed morphological
aspects of experimental work reported). ||
58.Hughes DI, Mackie M. Nagy GG, Riddell JS, Maxwell DJ, Szabo G, Erdelyi F, Veress G,
Szucs P, Antal M, Todd AJ (2005) P boutons in lamina IX ofthe rodent spinal cord express
high levels of glutamic acid decarboxylase-65 and originate from cells in deep medial dorsal
horn. Proc Natl Acad Sci USA. 102: 9038-9043. (Co-author; collaborative study with A.
Todd. Supervised and performed some aspects of experimental work reported). ||
59.Bannatyne. B.A., Edgley, S.A., Hammar, I., Jankowska, E. and Maxwell D.J. (2006)
Differential projections of excitatory and inhibitory dorsal horn interneurons relaying
information from group II muscle afferents in the cat spinal cord. J. Neurosci. 26: 2871-2880
(Co-author; collaborative study with E. Jankowska. Performed, initiated and supervised
morphological aspects of experimental work reported). ||
60.Erika Polgar, Suzanne Thomson, David J. Maxwell, Khulood Al-Khater and Andrew J. Todd
(20
Cult: A Composite Novel
No full textCult (redacted)
The first component of the thesis is a composite novel called Cult which falls into two parts with seven narratives in each. Part 1 tracks the protagonist, Ellen, from her first involvement with the cult through to her eventually leaving it. Although fiction, the first half of the book answers the kinds of questions the author is asked when people discover that she was once a sannyasin (a follower of the guru Bhagwan Shree Rajneesh). While the experiences of meditation, group therapy and communal living are all faithfully rendered within the stories, the need for strong characters, narrative drive and a lightness of touch takes precedence.
Part 2 picks up Ellen’s story some twenty or so years later and explores what becomes of her in middle age. It also looks at other groups in society, such as academia, the law and the internet dating community which each have their own jargon, hierarchies, rituals and rules but are not considered to be cults.
The book examines the question raised in the Epigraph, ‘how do we be together when we feel so alone’ with a focus on relationships other than the familial and the romantic.
Collisions, Chasms and Connections: a Performative Exploration of the Composite Novel Form
The second part of the thesis is both a critical and creative response to three contemporary American books: Olive Kitteridge by Elizabeth Strout; A Visit from the Goon Squad by Jennifer Egan; and Legend of a Suicide by David Vann. The critical element comprises a close reading of the three books; a chronological reconstruction of their overarching storylines; and a consideration of what their authors have said about writing the books. It concludes that, in the composite novel, the simultaneous presentation of multiple views and storylines operate much like a 3D image to give the impression of depth to the characters and situations rendered. The creative element of the essay is a playful and personal response to the texts
Etude de la rémanence de l'azinphos-méthyl utilisé contre Epiphyas postvittana Walker (Lepid. : Tortricidae) en Nouvelle-Zélande
No full textCan vibrational playbacks disrupt mating or influence other relevant behaviours in Bactericera cockerelli (Triozidae: Hemiptera)?
No full textBehaviours of insects can be manipulated by transmitting vibrational signals to host plants in order to develop pest management techniques. Bactericera cockerelli is an important pest and uses vibrations for mate-finding. In order to design a future control strategy for B. cockerelli, three different bioassays were performed to assess whether vibrational signals could affect relevant behaviours. Single males or pairs were treated with a female playback in test 1 and 2, respectively. In test 3, mixed sex groups received either different disturbance playbacks. The use of a female playback significantly reduced the mating success of males, since they were attracted towards the source of the stimulus. Moreover, test 2 revealed that B. cockerelli females are competitive, since they used their signals to cover the playback and to duet with males, while in test 3, the disturbance playback, consisting of broadband noises significantly reduced male signalling activity. However, none of the treatments of test 3 negatively affected the mating success of males, which tended to mount the other conspecifics present on the same leaf. The role of vibrations in sexual communication and their potential application as control technique for B. cockerelli are discussed as well
Etude de la rémanence de l'azinphos-méthyl utilisé contre Epiphyas postvittana Walker (Lepid. : Tortricidae) en Nouvelle-Zélande
No full textInternational audienc
Can we replace toxicants, achieve biosecurity, and generate market position with semiochemicals?
No full textBiosecurity covers both long-term management of existing pests and the urgent government responses to alien invasive species which have yet to become fully established. Mating disruption, mass trapping and lure and kill systems all have potential to be used in pest management and against new incursions of certain types of organisms, predominantly moths and beetles. Straight chained lepidopteran sex pheromones have emerged as a source of potential market advantage in pest management, with trapping systems and residue-free multiple species disruption systems being increasingly adopted to reduce insecticide use and meet private stabndard. Semiochemicals can also offer new surveillance tools in pre-border biosecurity, greatly improving the chances for successful eradication of alien invasive species. However, a rising frequency of incursions of alien invasive species and consequent rise in official eradication programs due to globalisation points strongly to the need for further investment in the areas of discovery and development of surveillance and eradication technologies, from a sound knowledge of chemical ecology
Effects of the Transcendental Meditation Program on Substance Use among University Students
No full textA randomized wait-list controlled trial (=295 university students) of the effects of the Transcendental Meditation program was conducted in an urban setting. Substance use was assessed by self-report at baseline and 3 months later. For smoking and illicit drug use, there were no significant differences between conditions. For alcohol use, sex X intervention condition interactions were significant; TM instruction lowered drinking rates among male but not female students. TM instruction could play a valuable role in reducing alcohol use among male university students. Limitations are noted, along with suggestions for further research
Vibrational communication in Psyllids
No full textPsyllids are small insects that can vector causal agents of serious plant
diseases, such as greening in citrus and zebra chip disease in potatoes. Several
invasive psyllid species are expanding their geographic range, but there are few
pest management tactics available at present. Vibrational communication is a primary intra-specific communication channel within Psylloidea, being widespread
among almost all the families. In psyllids, vibrational signals are used for mate
location and mate choice by means of a male–female duet. Depending on the
species, the first call can be emitted either by the male or the female and if a potential
mate replies, the duet is eventually established. Some psyllid males produce a
specific response signal when a female replies to their call, while in most other
species the male uses a unique type of vibrational signal throughout the mating process. Most psyllids likely emit vibrations by means of stridulation, in which
signals can be produced when the sclerotised areas of the anal vein of the wings rub
against the scutellum, which bears scale-like denticles. Recent evidence suggests
that novel methods of trapping or mating disruption using vibrational communication could provide solutions for monitoring and control psyllid pests. For instance,
the vibrational signals of the Asian citrus psyllid, Diaphorina citri, and the North
American tomato potato psyllid, Bactericera cockerelli, have been tested as monitoring and trapping tools, and similar studies have been initiated on other species
The principle of Ultra Vires and the local authorities’ decisions in England
No full textThe hypothesis of this thesis is that valid administrative decisions from local authorities are guaranteed via clear and precise enabling clauses in the primary legislation. Taking examples from local government in England, the author argues that the style of drafting local authorities’ legislations influences decisions taken by local authorities - so in attempting to exercise implied powers conferred by the imprecise enabling legislation and insufficient guidance, local authorities tend to go beyond intended legal powers and as a result take unreasonable, arbitrary and invalid decisions
Live traps for adult brown marmorated stink bugs
No full textSurveillance for detection of the brown marmorated stink bug, Halyomorpha halys, is reliant
on sticky panels with aggregation pheromone, which are low cost, but very inefficient (est. 3%).
Trapping for adults was conducted in Italy with novel live (or lethal) traps consisting of aggregation
pheromone-baited cylinders with a wind vane, with the upwind end covered by mesh and the
downwind end sealed by a removable entry-only mesh cone, admitting the attracted bugs. The novel
traps caught up to 15-times more adult H. halys than identically-baited sticky panels in two weeks
of daily checking (n = 6 replicates) (the new live traps were, in Run 1, 5-, 9-, 15-, 13-, 4-, 12-, 2-fold;
and in Run 2, 7-, 1-, 3-, 7-, 6-, 6-, and 5-fold better than sticky traps, daily). The maximum catch
of the new traps was 96 live adults in one trap in 24 h and the average improvement was ~7-fold
compared with sticky panels. The rotating live traps, which exploit a mesh funnel facing the plume
downwind that proved useful for collecting adults, could also be used to kill bugs. We expect that
commercially-available traps could replace the crude prototypes we constructed quickly from local
materials, at low cost, as long as the principles of a suitable plume structure were observed, as we
discuss. The traps could be useful for the sterile insect technique, supporting rearing colonies, or to
kill bug
- …
