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The appearance of cartilage used in deep inferior epigastric perforator breast reconstruction surgery as a calcified mass on CT scan.
This paper describes an unusual radiological appearance of implanted cartilage on CT scan in a patient who had recently undergone deep inferior epigastric perforator (DIEP) breast reconstruction surgery following a mastectomy for ductal carcinoma in situ. The purpose of this paper is to alert medical practitioners involved with DIEP breast reconstruction surgery, as well as general radiologists, to the possibility of surgically implanted costal cartilage undergoing calcification and then appearing on imaging studies as a malignant process. Information on the patient was gathered from clinical records, imaging reports and pathological samples. A literature search was performed to identify similar cases and the results showed that this occurrence has never before been described and therefore represents an advancement of knowledge about the imaging characteristics of reconstructed breast tissue
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Unsupervised Segmentation of 5D Hyperpolarized Carbon-13 MRI Data Using a Fuzzy Markov Random Field Model
Hyperpolarized MRI with 13C-labelled compounds
is an emerging clinical technique allowing in vivo metabolic processes
to be characterized non-invasively. Accurate quantification
of 13C data, both for clinical and research purposes, typically
relies on the use of region-of-interest analysis to detect and
compare regions of altered metabolism. However, it is not clear
how this should be determined from the five-dimensional data
produced and most standard methodologies are unable to exploit
the multidimensional nature of the data. Here we propose a
solution to the novel problem of 13C image segmentation using a
hybrid Markov random field model with continuous fuzzy logic.
The algorithm fully utilizes the multi-dimensional data format in
order to classify each voxel into one of six distinct classes based
on its metabolic characteristics. Bayesian priors fully incorporate
spatial, temporal and ratiometric contextual information whilst
image contrast from multiple spectral dimensions are considered
concurrently by using an analogy from color image segmentation.
Performance of the algorithm is demonstrated on in silico
data where the superiority of the approach over a reference
thresholding method is consistently observed. Application to in
vivo animal data from a pre-clinical subcutaneous tumor model
illustrates the ability of the MRF algorithm to successfully detect
tumor location whilst avoiding image artefacts. This work has
the potential to assist the analysis of human hyperpolarized 13C
data in the future.CJD is jointly funded by the National Institute for Health Research (NIHR), Cambridge Biomedical Research Centre and GlaxoSmithKline (GSK). The authors acknowledge further research support from Cancer Research UK (C19212/A911376, C19212/A16628), the Cancer Research UK/Engineering and Physical Sciences Research Council Imaging Centre in Cambridge and Manchester, the CRUK Cambridge Centre and Cambridge Experimental Cancer Medicine Centre
Athletesâ views on care in coaching: Perspectives of women footballers in the U.K.
In recent times, researchers have argued that coaches should develop relationships that are caring and meet the needs of athletes. Yet, the views of athletes themselves are notably absent from this research. In response, this study used interviews to explore the care experiences of 4 case study footballers. Findings demonstrated that; 1) club culture influenced the care that participants received; 2) dialogue was both an enabler of good care, but also a means of disseminating uncaring attitudes; 3) a âweb of careâ was provided by individuals other than the coach. These findings provide an original contribution by using the voice of athletes themselves to consider care in coaching
Dissolution Dominates Silica Cycling in a Shelf Sea Autumn Bloom
Autumn phytoplankton blooms represent key periods of production in temperate and highâlatitude seas. Biogenic silica (bSiO2) production, dissolution, and standing stocks were determined in the Celtic Sea (United Kingdom) during November 2014. Dissolution rates were in excess of bSiO2 production, indicating a net loss of bSiO2. Estimated diatom bSiO2 contributed â€10% to total bSiO2, with detritalbSiO2 supportingrapidSicycling.BasedontheaveragebiomassâspeciïŹcdissolutionrate(0.2dayâ1), 3weekswouldbeneededtodissolve99%ofthebSiO2 present.NegativenetbSiO2 productionwasassociated with lowâlight conditions (<4 E·mâ2·dayâ1). Our observations imply that dissolution dominates Si cycling during autumn, with lowâlight conditions also likely to inïŹuence Si cycling during winter and early spring
Seasonal phosphorus and carbon dynamics in a temperate shelf sea (Celtic Sea): uptake, partitioning, release, turnover and stoichiometry.
The seasonal cycle of resource availability in shelf seas has a strong selective pressure on phytoplankton diversity
and the biogeochemical cycling of key elements, such as carbon (C) and phosphorus (P). Shifts in carbon consumption
relative to P availability, via changes in cellular stoichiometry for example, can lead to an apparent
âexcessâ of carbon production. We made measurements of inorganic P (Pi) uptake, in parallel to C-fixation, by
plankton communities in the Celtic Sea (NW European Shelf) in spring (April 2015), summer (July 2015) and
autumn (November 2014). Short-term (< 8 h) Pi-uptake coupled with dissolved organic phosphorus (DOP) release,
in parallel to net (24 h) primary production (NPP), were all measured across an irradiance gradient designed
to typify vertically and seasonally varying light conditions. Rates of Pi-uptake were highest during spring
and lowest in the low light conditions of autumn, although biomass-normalised Pi-uptake was highest in the
summer. The release of DOP was highest in November and declined to low levels in July, indicative of efficient
utilization and recycling of the low levels of Pi available. Examination of daily turnover times of the different
particulate pools, including estimates of phytoplankton and bacterial carbon, indicated a differing seasonal
influence of autotrophs and heterotrophs in P-dynamics, with summer conditions associated with a strong
bacterial influence and the early spring period with fast growing phytoplankton. These seasonal changes in
autotrophic and heterotrophic influence, coupled with changes in resource availability (Pi, light) resulted in
seasonal changes in the stoichiometry of NPP to daily Pi-uptake (C:P ratio); from relatively C-rich uptake in
November and late April, to P-rich uptake in early April and July. Overall, these results highlight the seasonally
varying influence of both autotrophic and heterotrophic components of shelf sea ecosystems on the relative
uptake of C and P
Species-specific calcite production reveals Coccolithus pelagicus as the key calcifier in the Arctic Ocean
Through the production and export of their calcite coccoliths, coccolithophores form a key component of the global carbon cycle. Despite this key role, very little is known about the biogeochemical role of different coccolithophore species in terms of calcite production, and how these species will respond to future climate change and ocean acidification. Here, we present the first study to estimate species-specific calcite production, from samples collected in the Arctic Ocean and subarctic Iceland Basin in June 2012. We show that although the coccolithophorid Coccolithus pelagicus comprised only a small fraction of the total community in terms of abundance (2%), our estimates indicate that it was the major calcite producer in the Arctic Ocean and Iceland Basin (57% of total calcite production). In contrast, Emiliania huxleyi formed 27% of the total abundance and was responsible for only 20% of the calcite production. That C. pelagicus was able to dominate calcite production was due to its relatively high cellular calcite content compared with the other species present. Our results demonstrate, for the first time, the importance of investigating the complete coccolithophore community when considering pelagic calcite production, as relatively rare but heavily calcified species such as C. pelagicus can be the key calcite producers in mixed communities. Therefore, the response of C. pelagicus to ocean acidification and climate change has the potential to have a major impact on carbon cycling within the North Atlantic and Arctic Ocean
Plankton community respiration and bacterial metabolism in a North Atlantic Shelf Sea during spring bloom development (April 2015)
Spring phytoplankton blooms are important events in Shelf Sea pelagic systems as the increase in carbon production
results in increased food availability for higher trophic levels and the export of carbon to deeper waters
and the sea-floor. It is usually accepted that the increase in phytoplankton abundance and production is followed
by an increase in plankton respiration. However, this expectation is derived from field studies with a low
temporal sampling resolution (5â15 days). In this study we have measured the time course of plankton abundance,
gross primary production, plankton community respiration, respiration of the plankton size classes
(> 0.8 ÎŒm and 0.2â0.8 ÎŒm) and bacterial production at â€5 day intervals during April 2015 in order to examine
the phasing of plankton autotrophic and heterotrophic processes. Euphotic depth-integrated plankton community
respiration increased five-fold (from 22 ± 4 mmol O2mâ2 dâ1 on 4th April to 119 ± 4 mmol O2mâ2 dâ1
on 15th April) at the same time as gross primary production also increased five-fold, (from 114 ± 5 to
613 ± 28 mmol Cmâ2 dâ1). Bacterial production began to increase during the development of the bloom, but
did not reach its maximum until 5 days after the peak in primary production and plankton respiration. The
increase in plankton community respiration was driven by an increase in the respiration attributable to the>
0.8 ÎŒm size fraction of the plankton community (which would include phytoplankton, microzooplankton and
particle attached bacteria). Euphotic depth-integrated respiration of the 0.2â0.8 ÎŒm size fraction (predominantly
free living bacteria) decreased and then remained relatively constant (16 ± 3 â 11 ± 1 mmol O2mâ2 dâ1)
between the first day of sampling (4th April) and the days following the peak in chlorophyll-a (20th and 25th
April). Recent locally synthesized organic carbon was more than sufficient to fulfil the bacterial carbon requirement
in the euphotic zone during this productive period. Changes in bacterial growth efficiencies (BGE, the
ratio of bacterial production to bacterial carbon demand) were driven by changes in bacterial production rates
increasing from<30 ± 14% on 4th April to 51 ± 11% on 25th of April. This study therefore shows a concurrent
rather than a phased increase in primary production and community respiration attributable to
cells>0.8 ÎŒm during the development of the spring bloom, followed 5 days later by a peak in bacterial production.
In addition, the size fractionated respiration rates and high growth efficiencies suggest that free living
bacteria are not the major producers of CO2 before, during and a few days after this shelf sea spring phytoplankton
bloom
Validity, reliability and stability of the portable Cortex Metamax 3B gas analysis system
This study investigated the performance of the portable Cortex Metamax 3B (MM3B) automated gas analysis system during both simulated and human exercise using adolescents. Repeated measures using a Gas Exchange System Validator (GESV) across a range of simulated metabolic rates, showed the MM3B to be adequately reliable (both percentage errors, and percentage technical error of measurements <2%) for measuring expired ventilation (VE), oxygen consumption (VO2), and carbon dioxide production (VCO2). Over a 3Â h period, the MM3B was shown to be acceptably stable in measuring gas fractions, as well as VE, VO2, and VCO2 generated by the GESV, especially at moderate and high metabolic rates (drifts <2% and of minor physiological significance). Using eight healthy adolescents during rest, moderate, and vigorous cycle ergometry, the validity of the MM3B was tested against the primary criterion Douglas bag method (DBM) and a secondary criterion machine known to be accurate, the Jaeger Oxycon Pro system. No significant errors in VE were noted, yet the MM3B significantly overestimated both VO2 and VCO2 by approximately 10â17% at moderate and vigorous exercise as compared to the DBM and at all exercise levels compared to the Oxycon Pro. No significant differences were seen in any metabolic variable between the two criterion systems (DBM and Oxycon Pro). It is concluded the MM3B produces acceptably stable and reliable results, but is not adequately valid during moderate and vigorous exercise without some further correction of VO2 and VCO2
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