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The Potential of Freeform Construction Processes
The level of automation technology and processes control found in modern day construction
lags significantly behind other industries such as automotive and aerospace. The construction
industry has health and safety issues and still uses traditional methods of procurement. These
problems are compounded by diminishing skills in the labour force. Methods of production
must change if these issues are to be resolved and Freeform Construction is a collection of
processes that could have potential impact. This paper outlines some of the major issues
facing construction and sets a context with examples of digital fabrication in construction.
Freeform Construction is defined and potential applications are presented and related to
application scale. The viability of two potential applications are investigated in terms of cost.Mechanical Engineerin
A development appraisal from the management viewpoint of the use of cost-benefit analysis in in-company training situations
The thesis takes the economist's concept of cost-benefit analysis and subjects it to a ‘developmental appraisal', from the management viewpoint and in respect of ‘in-company training'. In so doing it seeks to explore the contribution that the broad concept, when applied to training evaluation, can make to management decision making. The thesis concludes from an appraisal of the cost-benefit concept that differences when it is applied to in-company training compared with the economists traditional 'macro' usage, merit a different label, 'investment appraisal' of training. The place of the concept in training evaluation is then explored and in use it is shown to be subject to a great many constraints. The thesis proposes that these constraints be translated as opportunities within a 'new' framework which seeks to consider training evaluation from the management viewpoint. This framework proposes a twin role for evaluation: the conventional one of feedback to the trainer and organisation; and an additional one of identification of the key 'supportive' systems needed to meet the objectives of a particular programme. To test these roles a dichotomy is proposed between Programmed and non-Programmed training decisions, within which a classification of types of training is suggested. The investment appraisal concept is then applied to evaluations within each of these decision categories. The non-Programmed decision evaluation is conducted in an operative training situation in a rolling mill in the steel industry; the Programmed Decision evaluation is applied to a junior operative training programme in several steel companies. The thesis concludes from the results of the experiments that a useful methodology has been devised and that the major contribution of the application of the concept in practice is the opportunity it gives both for the identification of line management contribution to the success of training and obtaining of their involvement
Warm HCN, C2H2, and CO in the disk of GV Tau
We present the first high-resolution, ground-based observations of HCN and
C2H2 toward the T Tauri binary star system GV Tau. We detected strong
absorption due to HCN nu_3 and weak C2H2 (nu_3 and nu_2 + (nu_4 + nu_5)^0_+)
absorption toward the primary (GV Tau S) but not the infrared companion. We
also report CO column densities and rotational temperatures, and present
abundances relative to CO of HCN/CO ~0.6% and C2H2/CO ~1.2% and an upper limit
for CH4/CO < 0.37% toward GV Tau S. Neither HCN nor C2H2 were detected toward
the infrared companion and results suggest that abundances may differ between
the two sources.Comment: 23 pages, 6 figures, accepted by Ap
A Proper Motion Study of the Haro 6-10 Outflow: Evidence for a Subarcsecond Binary
We present single-dish and VLBI observations of an outburst of water maser
emission from the young binary system Haro 6-10. Haro 6-10 lies in the Taurus
molecular cloud and contains a visible T Tauri star with an infrared companion
1.3" north. Using the Very Long Baseline Array, we obtained five observations
spanning 3 months and derived absolute positions for 20 distinct maser spots.
Three of the masers can be traced over 3 or more epochs, enabling us to extract
absolute proper motions and tangential velocities. We deduce that the masers
represent one side of a bipolar outflow that lies nearly in the plane of the
sky with an opening angle of ~45\deg. They are located within 50 mas of the
southern component of the binary, the visible T Tauri star Haro 6-10S. The mean
position angle on the sky of the maser proper motions (~220\deg) suggests they
are related to the previously observed giant Herbig-Haro (HH) flow which
includes HH410, HH411, HH412, and HH184A-E. A previously observed HH jet and
extended radio continuum emission (mean position angle of ~190\deg) must also
originate in the vicinity of Haro6-10S and represent a second, distinct outflow
in this region. We propose that a yet unobserved companion within 150 mas of
Haro6-10S is responsible for the giant HH/maser outflow while the visible star
is associated with the HH jet. Despite the presence of H_2 emission in the
spectrum of the northern component of the binary, Haro6-10N, none of
outflows/jets can be tied directly to this young stellar object
Uniaxial magnetocrystalline anisotropy in
is a paramagnetic metal and since its low temperature
resistivity is described by with , it
is also considered a non-Fermi liquid (NFL) metal. We have performed extensive
magnetoresistance and Hall effect measurements of untwinned epitaxial films of
. These measurements reveal that exhibits
uniaxial magnetocrystalline anisotropy. In addition, the low-temperature NFL
behavior is most effectively suppressed when a magnetic field is applied along
the easy axis, suggesting that critical spin fluctuations, possibly due to
proximity of a quantum critical phase transition, are related to the NFL
behavior.Comment: 7 figure
Survival of HIV-1 vertically infected children
PURPOSE OF REVIEW: It is 20 years since the start of the combination antiretroviral therapy (cART) era and more than 10 years since cART scale-up began in resource-limited settings. We examined survival of vertically HIV-infected infants and children in the cART era. RECENT FINDINGS: Good survival has been achieved on cART in all settings with up to 10-fold mortality reductions compared with before cART availability. Although mortality risk remains high in the first few months after cART initiation in young children with severe disease, it drops rapidly thereafter even for those who started with advanced disease, and longer term mortality risk is low. However, suboptimal retention on cART in routine programs threatens good survival outcomes and even on treatment children continue to experience high comorbidity risk; infections remain the major cause of death. Interventions to address infection risk include a cotrimoxazole prophylaxis, isoniazid preventive therapy, routine childhood and influenza immunization, and improving maternal survival. SUMMARY: Pediatric survival has improved substantially with cART and HIV-infected children are aging into adulthood. It is important to ensure access to diagnosis and early cART, good program retention as well as optimal comorbidity prophylaxis and treatment to achieve the best possible long-term survival and health outcomes for vertically infected children
Dawn to dusk counts of common or garden birds, Wellington, New Zealand
Abstract Common Iand-birds in a rural suburban garden, Wellington, New Zealand, were counted for 10 minutes twice an hour, twice a month for 2 years, from dawn to dusk. The birds' behaviour sometimes changed or they entered or left the study area during the day; so there is no ided time of day for counting buds
Nuclear BK channels regulate CREB phosphorylation in RAW264.7 macrophages
BACKGROUND: Macrophages are important cells of the innate immune system and contribute to a variety of physiological and pathophysiological responses. Monovalent and divalent ion channels have been studied in macrophage function, and while much research is still required, a role for these channels is beginning to emerge in macrophages. In addition to the plasma membrane, ion channels are also found in intracellular membranes including mitochondrial, lysosomal and nuclear membranes. While studying the function of plasma membrane located large conductance voltage- and calcium-activated potassium channels (BK channels) in a macrophage cell line RAW264.7, we became aware of the expression of these ion channels in other cellular locations. METHODS: Immunofluorescence and Western blot analysis were used to identify the expression of BK channels. To demonstrate a functional role for the nuclear located channel, we investigated the effect of the lipid soluble BK channel inhibitor paxilline on CREB phosphorylation. RESULTS: Treatment of resting macrophages with paxilline resulted in increased CREB phosphorylation. To confirm a role for nuclear BK channels, these experiments were repeated in isolated nuclei and similar results were found. Ca2+ and calmodulin-dependent kinases (CaMK) have been demonstrated to regulate CREB phosphorylation. Inhibition of CaMKII and CaMKIV resulted in the reversal of paxilline-induced CREB phosphorylation. CONCLUSIONS: These results suggest that nuclear BK channels regulate CREB phosphorylation in macrophages. Nuclear located ion channels may therefore be part of novel signalling pathways in macrophages and should be taken into account when studying the role of ion channels in these and other cells
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