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Forestry in a changing landscape: building professionalism in the British forestry sector
The institutions of Forestry in Great Britain are in flux. The Forestry Commission, the state forest service that has been the dominant presence in British forestry for almost a century, no longer operates in Wales and its future in England and Scotland is uncertain. The paper explores the internal and external socio-political environment of the forestry profession in Britain. It asks how contemporary society understands forestry, how this influences the profession and how, in turn, this understanding changes as forestry practice develops. From the perspective of the professional body for forestry, the Institute of Chartered Foresters, the paper also explores how the profession might maintain and enhance the voice of its members as decisions are made that will set the course of forestry for many years. The forestry sector traditionally has relied on the Forestry Commission to represent it and seems poorly placed to speak for itself. The Institute has neither the resources nor a mandate from its members to occupy the territory left vacant as the Forestry Commission diminishes. Also, the profession has an adaptive culture, better fitted to dealing with incremental change than to radical upheaval. Nevertheless foresters are trusted by the public. Their professional status combined with this strong reputation gives the profession a legitimating role in decision-making and standard-setting in forestry and a mandate to participate more actively in the development of the political and institutional frameworks for the sector.
Whilst 70% of professional foresters and arboriculturalists work in the private sector the Government will continue to be the most influential stakeholder in forestry. This is largely because of its regulatory power and its grant-aid schemes. However, ministers and officials see forestry as an environmental activity and give precedence to the views of environmental NGOs over those of the forestry profession. This does not necessarily reflect the way that society thinks about forests. Cultural associations, enjoyment of amenities such as recreation and landscape together with tacit concerns over the stewardship of nature contribute to a complex perspective on forests, trees and woodlands among the wider public. Within the profession there is a diversity of opinion over the role of foresters and different understandings of professional identity and norms. An argument is made that the professional identity of foresters is in part formed through the routines and the agency they derive from their work, and varies according to location and the nature of their tasks. Since the balance of these tasks is strongly influenced by geography there is likely to be a steady divergence in the construction of professional identity in the four countries of the UK. This presents a challenge for the profession in its role as the only remaining UK-wide forestry institution other than Forest Research, a Government research agency. The paper suggests that external change will be accompanied by increasing internal complexity within the professional association. The challenge for the professional body, therefore, is to remain engaged with this increasingly diverse membership whilst continuing to project a professional voice as the sector reshapes itself
Techniques for the Microanalysis of Higher Plants with Particular Reference to Silicon in Cryofixed Wheat Tissues
The applications of x-ray microanalysis in research into silicon in higher plants are reviewed, recent developments are assessed, and new data are presented. Conventionally prepared material [air or freeze drying for scanning electron microscopy (SEM), and glutaraldehyde/osmium tetroxide fixation for transmission electron microscopy (TEM)) has been studied using both wavelength and energy dispersive microanalysis. These techniques are reliable provided that the deposited form of silica is the major focus of investigation. Recently, studies concerning the soluble, mobile forms of silica, and the ionic environment at deposition sites have been initiated. In these investigations x -ray microanalysis has been carried out on the cold stage of an SEM, or after freeze substitution on sections in TEM. Two other developments which are considered are the use of proton induced x-ray emission, and electron energy loss spectroscopy.
To illustrate the most recent developments in this field we present new observations on mineral distribution in the culm and awn of wheat using microanalysis of frozen hydrated material in SEM, and in the wheat leaf using freeze substitution and TE M and scanning transmission electron microscopy
The Multifragmentation Freeze--Out Volume in Heavy Ion Collisions
The reduced velocity correlation function for fragments from the reaction Fe
+ Au at 100 A~MeV bombarding energy is investigated using the
dynamical--statistical approach QMD+SMM and compared to experimental data to
extract the Freeze--Out volume assuming simultaneous multifragmentation.Comment: 8 pages; 3 uuencoded figures available with figures command, LateX,
UCRL-J-1157
Generation of Intrinsic Vibrational Gap Modes in Three-Dimensional Ionic Crystals
The existence of anharmonic localization of lattice vibrations in a perfect
3-D diatomic ionic crystal is established for the rigid-ion model by molecular
dynamics simulations. For a realistic set of NaI potential parameters, an
intrinsic localized gap mode vibrating in the [111] direction is observed for
fcc and zinc blende lattices. An axial elastic distortion is an integral
feature of this mode which forms more readily for the zinc blende than for the
fcc structure. Molecular dynamics simulations verify that in each structure
this localized mode may be stable for at least 200 cycles.Comment: 5 pages, 4 figures, RevTeX, using epsf.sty. To be published in Phys.
Rev. B. Also available at http://www.msc.cornell.edu/~kiselev
The generation of influenza-specific humoral responses is impaired in ST6Gal I-deficient mice.
Posttranslational modification of proteins, such as glycosylation, can impact cell signaling and function. ST6Gal I, a glycosyltransferase expressed by B cells, catalyzes the addition of alpha-2,6 sialic acid to galactose, a modification found on N-linked glycoproteins such as CD22, a negative regulator of B cell activation. We show that SNA lectin, which binds alpha-2,6 sialic acid linked to galactose, shows high binding on plasma blasts and germinal center B cells following viral infection, suggesting ST6Gal I expression remains high on activated B cells in vivo. To understand the relevance of this modification on the antiviral B cell immune response, we infected ST6Gal I(-/-) mice with influenza A/HKx31. We demonstrate that the loss of ST6Gal I expression results in similar influenza infectivity in the lung, but significantly reduced early influenza-specific IgM and IgG levels in the serum, as well as significantly reduced numbers of early viral-specific Ab-secreting cells. At later memory time points, ST6Gal I(-/-) mice show comparable numbers of IgG influenza-specific memory B cells and long-lived plasma cells, with similarly high antiviral IgG titers, with the exception of IgG2c. Finally, we adoptively transfer purified B cells from wild-type or ST6Gal I(-/-) mice into B cell-deficient (microMT(-/-)) mice. Recipient mice that received ST6Gal I(-/-) B cells demonstrated reduced influenza-specific IgM levels, but similar levels of influenza-specific IgG, compared with mice that received wild-type B cells. These data suggest that a B cell intrinsic defect partially contributes to the impaired antiviral humoral response
An Early CD4+ T Cell–dependent Immunoglobulin A Response to Influenza Infection in the Absence of Key Cognate T–B Interactions
Contact-mediated interactions between CD4+ T cells and B cells are considered crucial for T cell–dependent B cell responses. To investigate the ability of activated CD4+ T cells to drive in vivo B cell responses in the absence of key cognate T–B interactions, we constructed radiation bone marrow chimeras in which CD4+ T cells would be activated by wild-type (WT) dendritic cells, but would interact with B cells that lacked expression of either major histocompatibility complex class II (MHC II) or CD40. B cell responses were assessed after influenza virus infection of the respiratory tract, which elicits a vigorous, CD4+ T cell–dependent antibody response in WT mice. The influenza-specific antibody response was strongly reduced in MHC II knockout and CD40 knockout mice. MHC II–deficient and CD40-deficient B cells in the chimera environment also produced little virus-specific immunoglobulin (Ig)M and IgG, but generated a strong virus-specific IgA response with virus-neutralizing activity. The IgA response was entirely influenza specific, in contrast to the IgG2a response, which had a substantial nonvirus-specific component. Our study demonstrates a CD4+ T cell–dependent, antiviral IgA response that is generated in the absence of B cell signaling via MHC II or CD40, and is restricted exclusively to virus-specific B cells
The use of the 1 mm laparoscope to assist in port insertion in pelvic oncological surgery
BACKGROUND: A 1 mm minilaparoscope (Lifeline Biotechnoligies, Florida, USA) was assessed for aiding port site insertions. METHODS: Ten consecutive patients having laparoscopic procedures in a gynaecological oncology unit were included. Minilaparoscopy was feasible in all cases and was used to insert the umbilical port under direct vision in all patients. In one case, a thick band of abdominal adhesions was identified and a further lateral port site was inserted to aid their dissection. RESULTS: The minilaparoscope correctly identified all 10 patients with peritoneal disease and identified all patients who were suitable for debulking procedures. CONCLUSION: Minilaparoscopy with the 1 mm endoscope appears to be safe and accurate and we feel that it has a place in helping the surgeon identify adhesions and peritoneal disease as well as assisting further port site insertion safely and with minimal complications
Correspondences and Quantum Description of Aharonov-Bohm and Aharonov-Casher Effects
We establish systematic consolidation of the Aharonov-Bohm and
Aharonov-Casher effects including their scalar counterparts. Their formal
correspondences in acquiring topological phases are revealed on the basis of
the gauge symmetry in non-simply connected spaces and the adiabatic condition
for the state of magnetic dipoles. In addition, investigation of basic two-body
interactions between an electric charge and a magnetic dipole clarifies their
appropriate relative motions and discloses physical interrelations between the
effects. Based on the two-body interaction, we also construct an exact
microscopic description of the Aharonov-Bohm effect, where all the elements are
treated on equal footing, i.e., magnetic dipoles are described
quantum-mechanically and electromagnetic fields are quantized. This microscopic
analysis not only confirms the conventional (semiclassical) results and the
topological nature but also allows one to explore the fluctuation effects due
to the precession of the magnetic dipoles with the adiabatic condition relaxed
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