483 research outputs found
Transience and durability in Japanese urban space
The thesis addresses the research question âWhat is transient and what endures within Japanese urban spaceâ by taking the material constructed form of one Japanese city as a primary text and object of analysis. Chiba-shi is a port and administrative centre in southern Kanto, the largest city in the eastern part of the Tokyo Metropolitan Region and located about forty kilometres from downtown Tokyo.
The study privileges the role of process as a theoretical basis for exploring the dynamics of the production and transformation of urban space. Three aspects of temporal experience identified by Giddens â routine, biographical and institutional time â are adopted as a framework for considering how the dynamics of social reproduction are expressed in terms of transience and durability within urban form.
A methodology is developed to explore the changing interrelationship between six conceptual âentitiesâ â the individual, household, dwelling, establishment, premises and site. Metrics are identified for each to facilitate a consistent analysis over time of the changing relationship between these based on a formal diachronic longitudinal survey. An analysis of the spatial transformation of the material form of the city between 1870 and 2005 was completed based primarily on recording the changing use over time of about 4,500 sample points.
The outcome of the study is presented in five substantive chapters. The first considers characteristics of the layout of neighbourhoods and dwellings that have endured largely through their close association with processes of social reproduction. The following four chapters examine chronologically the evolution of the city, documenting transformations in urban form and their expression in terms of changing use of volumes of space, the characteristic infrastructure, premises and dwelling types, and how these relate to broader trends in Japanese history. The final chapter summarises the interrelationship of these transformations and draws some conclusions concerning what promotes transience and durability in an urban environment
Multi-scale modelling of effluent dispersion in the marine environment
This research aimed to investigate whether the unique numerical methods
available within CFD model software Fluidity could progress the stateâ
ofâtheâart in various aspects of modelling effluent dispersion within the
marine environment. Fluidity contains a large library of models and numerical
methods that enable modelling of flow processes at a wide range
of scales. It has been proven to perform well when used for massivelyâ
parallel simulations (i.e. it scales well), and it has the unâcommon facility
of unstructured mesh adaptivity, which has the prospect of significantly
increasing the efficiency of CFD simulations when guided skillfully.
This research also forms part of a longerâterm project to create a coupled
(or even single) model of effluent dispersion that represents influencing
factors from a wide range of scales (from tidal currents down to turbulent
eddies) entirely using CFD techniques. As such, one aspect of the
research was to validate the numerical methods available within Fluidity
for use in modelling effluent dispersion. To facilitate this validation, some
of the model studies investigate aspects of effluent dispersion modelling
from a hypothetical outfall site off the NorthâEast coast of the United
Kingdom.
Studies were performed in a series of stages in which key aspects of effluent
dispersion modelling were addressed. CFD models were created
of nearâfield jet dispersion, tidal motion, and farâfield plume dispersion.
Idealised test cases were also performed to investigate the performance of
advectionâdiffusion solver methods. At each stage the aim was to investigate
the benefit of novel numerical modelling techniques and compare
their accuracy and efficiency to existing methods.
A set of nearâfield buoyant jet dispersion CFD models were created, one
representing conditions associated with power, and combined power and
desalination plants, and one representing conditions typically associated
with desalination discharge. These CFD models utilised a mesh adaptivity
algorithm to optimise mesh resolution during the course of the
simulation. Model predictions were compared with published laboratory
data and the predictions from validated integral models. An assessment
was made of when CFD offers a benefit over other modelling options, and
when it might be sufficient to use cheaper tools. There was also a discussion of the effectiveness of mesh adaptivity in increasing model efficiency,
together with advice for how and when it is best to use mesh adaptivity
when modelling buoyant jet dispersion. Model results showed that with
modest parallel computing resources and expertise, highâresolution simulations
of jet dynamics can be achieved with reasonable accuracy using
CFD modelling.
A model was created of tidal flow within the European continental shelf
and results were compared to a large database of tide gauge measurements.
This model took advantage of recently published methods for
ocean model meshing and coastline resolution reduction. The purpose of
this study was to confirm that these methods offered a benefit to model
accuracy and efficient, and also that Fluidity could be used to accurately
generate the tidal forcing boundary conditions for a farâfield model of
effluent dispersion at a hypothetical outfall site.
The predictions of M2 tide amplitude in the vicinity of the outfall site
had an average error of 10.1% compared with tide gauge measurements.
The predictions of S2 tide amplitude in the vicinity of the outfall site
were even closer to tide gauge measurements, with an average error of
3.7%. The speed of the model solve showed a vast improvement over
a previous comparison model study, with 37 days of tidal motion being
simulated in 15.2 hours (58.4 seconds of simulation for each second of
solving), compared to the comparison simulation with a similar level of
accuracy, which simulated 2 seconds of tidal motion for every second of
solver time.
A series of simplified test cases were run to assess a commonlyâused
advectionâdiffusion solution method from the library of those available
within Fluidity. This work was intended to give general confidence that
the numerical methods available within Fluidity are suitable for modelling
coastal processes and so give confidence in later multiâscale results.
The test cases chosen were relevant to coastal dispersion, including those
testing tracer advection, diffusion, point sources and stratification. The
method compared well with results published using worldâleading free
surface modelling software, Open TELEMAC.
A model was created of the dispersion of neutrallyâbuoyant dissolved
pollutant from a hypothetical outfall. The assumed effluent is typical of
that released from a manufacturing plant. The aim of this modelling was
to validate the use of Fluidity for modelling effluent dispersion within
the coastal zone, and also investigate the benefit of using 2âd horizontal
mesh adaptivity to optimise model mesh resolution during the course of the simulation. It was shown that the use of mesh adaptivity improved
model efficiency, significantly lowering the effect of numerical diffusion.
Finally, a short outline was given of a prospective strategy for producing
a coupledâmodel of effluent dispersion, using as a basis the techniques
developed within this thesis. The proposed coupled model of effluent
dispersion would include a nearâfield jet model twoâway (i.e. âfullyâ
coupledâ) to a farâfield plume model. Tidal forcing would be provided
by a oneâway coupled tidal model. Fluidity is capable of modelling all
of these processes and so third party coupling software would be unnecessary.Open Acces
Nonlinear laser microscopy for the study of virusâhost interactions
Biomedical imaging is a key tool for the study of host-pathogen interactions. New techniques
are enhancing the quality and flexibility of imaging systems, particularly as a result of developments
in laser technologies. This work applies the combination of two advanced laser imaging
methods to study the interactions between a virus and the host cells it infects.
The first part of this work describes the theory and experimental implementation of coherent
anti-Stokes Raman scattering microscopy. This techniqueâfirst demonstrated in its current
form in 1999âpermits the imaging of microscopic samples without the need for fluorescent
labelling. Chemical contrast in images arises from the excitation of specific vibrations in the
sample molecules themselves. A laser scanning microscope system was set up, based on an
excitation source consisting of two titanium-sapphire lasers synchronized with a commercial
phase-locked loop system. A custom-built microscope was constructed to provide optimal
imaging performance, high detection sensitivity and straightforward adaptation to the specific
requirements of biomedical experiments. The system was fully characterized to determine its
performance.
The second part of this work demonstrates the application of this microscope platform in
virology. The microscope was configured to combine two nonlinear imaging modalities: coherent
anti-Stokes Raman scattering and two-photon excitation. Mouse fibroblast cells were
infected with a genetically modified cytomegalovirus. The modification causes the host cell
to express the green fluorescent protein upon infection. The host cell morphology and lipid
droplet distribution were recorded by imaging with coherent anti-Stokes Raman scattering,
whilst the infection was monitored by imaging the viral protein expression with two-photon
excitation. The cytopathic effects typical of cytomegalovirus infection were observed, including
expansion of the nucleus, rounding of the cell shape, and the appearance of intracellular
viral inclusions. In some cases these effects were accompanied by dense accumulations of lipid
droplets at the nuclear periphery. Imaging was performed both with fixed cells and living. It
was demonstrated that the lipid droplets in a single live cell could be imaged over a period of
7 hours without causing noticeable laser-induced damage. The system is shown to be a flexible
and powerful tool for the investigation of virus replication and its effects on the host cell
A phagocytic route for uptake of double-stranded RNA in RNAi.
RNA interference (RNAi) has a range of physiological functions including as a defence mechanism against viruses. To protect uninfected cells in a multicellular organism, not only a cell-autonomous RNAi response is required but also a systemic one. However, the route of RNA spread in systemic RNAi remains unclear. Here we show that phagocytosis can be a route for double-stranded RNA uptake. Double-stranded RNA expressed in Escherichia coli induces robust RNAi in Drosophila S2 cells, with effectiveness comparable to that of naked dsRNA. We could separate this phagocytic uptake route from that for RNAi induced by naked dsRNA. Therefore, phagocytic uptake of dsRNA offers a potential route for systemic spread of RNAi
Optimized Spectrometers Characterization Procedure for Near Ground Support of ESA FLEX Observations: Part 1 Spectral Calibration and Characterisation
The paper presents two procedures for the wavelength calibration, in the oxygen telluric absorption spectral bands (O2-A, Îťc = 687 nm and O2-B, Îťc = 760.6 nm), of field fixed-point spectrometers used for reflectance and Sun-induced fluorescence measurements. In the first case, Ne and Ar pen-type spectral lamps were employed, while the second approach is based on a double monochromator setup. The double monochromator system was characterized for the estimation of errors associated with different operating configurations. The proposed methods were applied to three Piccolo Doppio-type systems built around two QE Pros and one USB2 + H16355 Ocean Optics spectrometers. The wavelength calibration errors for all the calibrations performed on the three spectrometers are reported and potential methodological improvements discussed. The suggested calibration methods were validated, as the wavelength corrections obtained by both techniques for the QE Pro designed for fluorescence investigations were similar. However, it is recommended that a neon emission line source, as well as an argon or mercury-argon source be used to have a reference wavelength closer to the O2-B feature. The wavelength calibration can then be optimised as close to the O2-B and O2-A features as possible. The monochromator approach could also be used, but that instrument would need to be fully characterized prior to use, and although it may offer a more accurate calibration, as it could be tuned to emit light at the same wavelengths as the absorption features, it would be more time consuming as it is a scanning approach
Golfers have a greater improvement in their hip specific function compared to non-golfers after total hip arthroplasty but less than three-quarters returned to golf
AIMS: Golf is a popular pursuit among those requiring total hip arthroplasty (THA). The aim of this study was to determine if participating in golf is associated with greater functional outcomes, satisfaction, or improvement in quality of life (QoL) compared to non-golfers. METHODS: All patients undergoing primary THA over a one-year period at a single institution were included with one-year postoperative outcomes. Patients were retrospectively followed up to assess if they had been golfers at the time of their surgery. Multivariate linear regression analysis was performed to assess the independent association of preoperative golfing status on outcomes. RESULTS: The study cohort consisted of a total of 308 patients undergoing THA, of whom 44 were golfers (14%). This included 120 male patients (39%) and 188 female patients (61%), with an overall mean age of 67.8 years (SD 11.6). Golfers had a greater mean postoperative Oxford Hip Score (OHS) (3.7 (95% confidence interval (CI) 1.9 to 5.5); p < 0.001) and EuroQol visual analogue scale (5.5 (95% CI 0.1 to 11.9); p = 0.039). However, there were no differences in EuroQoL five-dimension score (p = 0.124), pain visual analogue scale (p = 0.505), or Forgotten Joint Score (p = 0.215). When adjusting for confounders, golfers had a greater improvement in their Oxford Hip Score (2.7 (95% CI 0.2 to 5.3); p < 0.001) compared to non-golfers. Of the 44 patients who reported being golfers at the time of their surgery, 32 (72.7%) returned to golf and 84.4% of those were satisfied with their involvement in golf following surgery. Those who returned to golf were more likely to be male (p = 0.039) and had higher (better) preoperative health-related QoL (p = 0.040) and hip-related functional scores (p = 0.026). CONCLUSION: Golfers had a greater improvement in their hip-specific function compared to non-golfers after THA. However, less than three-quarters of patients return to golf, with male patients and those who had greater preoperative QoL or hip-related function being more likely to return to play. Cite this article: Bone Jt Open 2022;3(2):145â151
Repetitive Stimulation of the Pituitary with Growth-Hormone-Releasing Hormone Alters the Proportion of 22 and 20 Kilodalton Human-Growth Hormone Released
Background/Aims. 20 Kilodalton-hGH (20âK-hGH) is the second most abundant pituitary GH variant after 22âK-hGH. In the steady state the proportion of 20â:â22âK-hGH appears constant; does this proportion change with repetitive somatotroph stimulation? Methods. Forty adult males were randomised to receive a GHRH(1â29)NH2 bolus (0.5âÎźg/kg (n = 20) or 1.0âÎźg/kg (n = 20)), preceded or followed by a saline bolus, 1 week apart. Four to six weeks later, 10 subjects received 0.5âÎźg/kg GHRH(1â29)NH2 at 0, 60, 120, and 180 minutes. Clearance rate of 22 and 20âK-hGH was measured in 10 subjects. Results. Total amount/proportion of 22âK-hGH/20âK-hGH secreted was similar for both GHRH(1â29)NH2 doses. Repetitive stimulation reduced the amount of 22âK-hGH released whereas the amount of 20âK-hGH did not change significantly leading to an increase in the proportion of 20âK-hGH (P = .05). Half-life of 20 and 22âK-hGH were not significantly different (P = .55). Conclusions. Repetitive stimulation of the somatotroph may alter the proportion of GH variant released
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