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Career conversations in coaching: the contribution that career theory can make to coaching practice
This paper responds to calls for an increased evidence base for coaching practice by exploring the contribution that career research and theory could make to this field. The paper summarises three small-scale studies focusing on career change undertaken by post-graduate students enrolled on an MSc in Career Coaching at a university in London. The studies explore the experiences of three groups of people who have recently changed career direction: female Black African entrepreneurs, academic research scientists moving to industry and people choosing a career in careers. The findings of the studies highlight the role of meaning and values, and the influence of others on career choice. The studies show too how the participants wrestle with subjective notions of career success, and that the impetus to make a career change comes from both a disenchantment with one situation and an attraction towards another. The paper concludes with some suggestions for coaching practice
Hyperextended Scalar-Tensor Gravity
We study a general Scalar-Tensor Theory with an arbitrary coupling funtion
but also an arbitrary dependence of the ``gravitational
constant'' in the cases in which either one of them, or both, do not
admit an analytical inverse, as in the hyperextended inflationary scenario. We
present the full set of field equations and study their cosmological behavior.
We show that different scalar-tensor theories can be grouped in classes with
the same solution for the scalar field.Comment: latex file, To appear in Physical Review
Multidimensional Cosmology: Spatially Homogeneous models of dimension 4+1
In this paper we classify all 4+1 cosmological models where the spatial
hypersurfaces are connected and simply connected homogeneous Riemannian
manifolds. These models come in two categories, multiply transitive and simply
transitive models. There are in all five different multiply transitive models
which cannot be considered as a special case of a simply transitive model. The
classification of simply transitive models, relies heavily upon the
classification of the four dimensional (real) Lie algebras. For the orthogonal
case, we derive all the equations of motion and give some examples of exact
solutions. Also the problem of how these models can be compactified in context
with the Kaluza-Klein mechanism, is addressed.Comment: 24 pages, no figures; Refs added, typos corrected. To appear in CQ
Airborne observations of aerosol microphysical properties and particle ageing processes in the troposphere above Europe
In-situ measurements of aerosol microphysical properties were performed in May 2008 during the EUCAARI-LONGREX campaign. Two aircraft, the FAAM BAe-146 and DLR Falcon 20, operated from Oberpfaffenhofen, Germany. A comprehensive data set was obtained comprising the wider region of Europe north of the Alps throughout the whole tropospheric column. Prevailing stable synoptic conditions enabled measurements of accumulating emissions inside the continental boundary layer reaching a maximum total number concentration of 19 000 particles cm<sup>â3</sup> stp. Ultra-fine particles as indicators for nucleation events were observed within the boundary layer during high pressure conditions and after updraft of emissions induced by frontal passages above 8 km altitude in the upper free troposphere. Aerosol ageing processes during air mass transport are analysed using trajectory analysis. The ratio of particles containing a non-volatile core (250 °C) to the total aerosol number concentration was observed to increase within the first 12 to 48 h from the particle source from 50 to 85% due to coagulation. Aged aerosol also features an increased fraction of accumulation mode particles of approximately 40% of the total number concentration. The presented analysis provides an extensive data set of tropospheric aerosol microphysical properties on a continental scale which can be used for atmospheric aerosol models and comparisons of satellite retrievals
Modeling the evolution of aerosol particles in a ship plume using PartMC-MOSAIC
This study investigates the evolution of ship-emitted aerosol
particles using the stochastic particle-resolved model
PartMC-MOSAIC (Particle Monte Carlo model-Model for Simulating Aerosol Interactions and Chemistry). Comparisons of our results with observations from the
QUANTIFY (Quantifying the Climate Impact of Global
and European Transport Systems) study in 2007 in the English Channel and the Gulf of Biscay
showed that the model was able to reproduce the observed evolution
of total number concentration and the vanishing of the nucleation
mode consisting of sulfate particles. Further process analysis
revealed that during the first hour after emission, dilution reduced
the total number concentration by four orders of magnitude, while
coagulation reduced it by an additional order of
magnitude. Neglecting coagulation resulted in an overprediction of
more than one order of magnitude in the number concentration of
particles smaller than 40 nm at a plume age of 100 s. Coagulation
also significantly altered the mixing state of the particles,
leading to a continuum of internal mixtures of sulfate and black
carbon. The impact on cloud condensation nuclei (CCN) concentrations
depended on the supersaturation threshold <i>S</i> at which CCN activity
was evaluated. For the base case conditions, characterized
by a low formation rate of secondary aerosol species, neglecting
coagulation, but simulating condensation, led to an
underestimation of CCN concentrations of about 37% for <i>S</i> = 0.3%
at the end of the 14-h simulation. In contrast, for
supersaturations higher than 0.7%, neglecting coagulation
resulted in an overestimation of CCN concentration, about 75% for
<i>S</i> = 1%. For <i>S</i> lower than 0.2% the differences between
simulations including coagulation and neglecting coagulation were
negligible. Neglecting condensation, but simulating coagulation
did not impact the CCN concentrations below 0.2% and resulted in
an underestimation of CCN concentrations for larger
supersaturations, e.g., 18% for <i>S</i> = 0.6%. We also explored the
role of nucleation for the CCN concentrations in the ship
plume. For the base case the impact of nucleation on CCN
concentrations was limited, but for a sensitivity case with higher
formation rates of secondary aerosol over several hours, the CCN
concentrations increased by an order of magnitude for
supersaturation thresholds above 0.3%
Protein aggregate formation permits millennium-old brain preservation
Human proteins have not been reported to survive in free nature, at ambient temperature, for long periods. Particularly, the human brain rapidly dissolves after death due to auto-proteolysis and putrefaction. The here presented discovery of 2600-year-old brain proteins from a radiocarbon dated human brain provides new evidence for extraordinary long-term stability of non-amyloid protein aggregates. Immunoelectron microscopy confirmed the preservation of neurocytoarchitecture in the ancient brain, which appeared shrunken and compact compared to a modern brain. Resolution of intermediate filaments (IFs) from protein aggregates took 2â12 months. Immunoassays on micro-dissected brain tissue homogenates revealed the preservation of the known protein topography for grey and white matter for type III (glial fibrillary acidic protein, GFAP) and IV (neurofilaments, Nfs) IFs. Mass spectrometry data could be matched to a number of peptide sequences, notably for GFAP and Nfs. Preserved immunogenicity of the prehistoric human brain proteins was demonstrated by antibody generation (GFAP, Nfs, myelin basic protein). Unlike brain proteins, DNA was of poor quality preventing reliable sequencing. These long-term data from a unique ancient human brain demonstrate that aggregate formation permits for the preservation of brain proteins for millennia
Avaliação da estratégia de tratamento parcial do rebanho no controle da mosca-dos-chifres.
A mosca-dos-chifres (MDC) destaca-se dentre os principais ectoparasitos que acometem a pecuĂĄria de corte nacional. Seu controle Ă© realizado quase exclusivamente com produtos inseticidas, o que tem levado a sĂ©rios problemas de resĂduos e resistĂȘncia. Alternativas nĂŁo quĂmicas e redução do uso de inseticidas tornam-se essenciais ao controle sustentĂĄvel deste parasito. O presente estudo avaliou a eficiĂȘncia do tratamento parcial do rebanho como estratĂ©gia de controle da MDC. Quatro experimentos foram conduzidos, utilizando produtos de diferentes classes inseticidas: lactona macrocĂclica (ivermectina), fenilpirazol (fipronil), piretrĂłide cipermetrina) e organofosforado+piretrĂłide (clorpirifĂłs+cipermetrina), em formulaçÔes pour-on. Em cada experimento, 200 vacas Nelore foram distribuĂdas em quatro grupos, para avaliação do tratamento de 20%, 50% e 100% do rebanho, alĂ©m de um grupo nĂŁo tratado. Contagens periĂłdicas da MDC foram realizadas nos dias 0, 3, 7, 14, 21 e 28 em todos os animais. A eficĂĄcia dos produtos nos grupos tratados integralmente foi superior a 90% (exceto pela cipermetrina) ao final da 1ÂȘ semana pĂłs-tratamento, sendo de modo geral superior a dos tratados parcialmente nas duas semanas iniciais. Nos grupos tratados parcialmente, a eficĂĄcia foi geralmente maior nos grupos com maior frequĂȘncia de animais tratados. Independente da classe inseticida aplicada e do percentual de animais tratados (20% ou 50%), o tratamento parcial do rebanho apresentou trĂȘs caracterĂsticas principais: a) rĂĄpida e acentuada redução das infestaçÔes em todo o rebanho, b) menores nĂveis de redução das infestaçÔes e c) menor perĂodo de proteção, em relação ao tratamento de todo o rebanho. Apesar da redução no uso de inseticidas e do menor custo, a viabilidade do tratamento parcial do rebanho, como estratĂ©gia de controle da MDC, se limita a situaçÔes onde um menor nĂvel e perĂodo de eficĂĄcia sejam aceitĂĄveis, caso contrĂĄrio, tratamentos adicionais podem ser necessĂĄrios, comprometendo as vantagens da estratĂ©gia. As implicaçÔes do tratamento parcial do rebanho no desenvolvimento e manejo da resistĂȘncia a inseticidas devem ser avaliadas. The horn fly stands out among the main ectoparasites that affect national beef cattle. This livestock pest is controlled almost exclusively by insecticide products, which has led to serious residue and resistance issues. Non-chemical alternatives and reduction of insecticide use are essential for a sustainable control of this parasite. This study evaluated the efficiency of partial herd treatment as a strategy for controlling horn flies. Four experiments were conducted using products from different insecticide classes: macrocyclic lactone (ivermectin) phenylpyrazole (fipronil), pyrethroid (cypermethrin), and an organophosphate-pyrethroid mixture (chlorpyrifos + cypermethrin), in pour-on formulations. In each experiment, 200 Nelore cows were distributed in four groups for evaluation of the treatment of 20, 50, and 100% of the herd, besides an untreated group. Periodic fly counts were performed on days 0, 3, 7, 14, 21, and 28 in all animals. Product efficacy in the full-treated herd exceeded 90% (except for cypermethrin) at the end of the 1st week after treatment, being mostly higher than in partially treated groups in the first two weeks. In the groups partially treated, efficacy was generally higher in the groups with the largest frequency of treated animals. Regardless of the insecticide class and the percentage of treated animals (20% or 50%), the partial treatment of the herd showed three main features: a) fast and marked reduction in infestations throughout the herd, b) lower reduction of horn fly infestations, and c) shorter period of protection, when compared to the full herd treatment. Despite reduction in insecticide use and lower costs, viability of partial herd treatment as a strategy for controlling the horn fly is limited to situations where a lower level and protection period are acceptable; otherwise, the need for additional treatments tends to compromise the advantages of the strategy. The implications of partial herd treatment in the development and management of insecticide resistance should be evaluated.bitstream/item/129471/1/BP125.pd
Marathon related death due to brainstem herniation in rehydration-related hyponatraemia: a case report
Introduction: Identifying marathon runners at risk of neurological deterioration at the end of the race (within a large cohort complaining of exhaustion, dehydration, nausea, headache, dizziness, etc.) is challenging. Here we report a case of rehydration-related hyponatraemia with ensuing brain herniation.
Case presentation: We report the death of runner in his 30's who collapsed in the recovery area following a marathon. Following rehydration he developed a respiratory arrest in the emergency room. He was found to be hyponatraemic (130 mM). A CT brain scan showed severe hydrocephalus and brain stem herniation. Despite emergency insertion of an extraventricular drain, he was tested for brainstem death the following morning. Funduscopy demonstrated an acute-on-chronic papilledema; CSF spectrophotometry did not reveal any trace of oxyhemoglobin or bilirubin, but ferritin levels were considerably raised (530 ng/mL, upper reference value 12 ng/mL), consistent with a previous bleed. Retrospectively it emerged that the patient had suffered from a thunderclap headache some months earlier. Subsequently he developed morning headaches and nausea. This suggests that he may have suffered from a subarachnoid haemorrhage complicated by secondary hydrocephalus. This would explain why in this case the relatively mild rehydration-related hyponatremia may have caused brain swelling sufficient for herniation.
Conclusion: Given the frequency of hyponatraemia in marathon runners (serum Na <135 mM in about 13%), and the non-specific symptoms, we discuss how a simple screening test such as funduscopy may help to identify those who require urgent neuroimaging
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