Developing a mathematical model for vegetative plant growth in broccoli

Two experiments were conducted during 1987 and 1988 at the University of Tennessee Plant and Soil Science greenhouse. Premium Crop broccoli (Brassica oleracea L. Group Italica) plants were grown to develop a database from which an empirical mathematical model for vegetative growth could be developed. A model predicting the time from seeding to visible bud and another model showing the development of the inflorescence were also investigated. Plants were grown in shaded chambers within a greenhouse at 30, 50, 70, and 100% of full sunlight. Light treatments were arranged in a randomized complete block design with 3 replications. The Photosynthetic Photon Flux (PPF) density was recorded at 1-minute intervals in each experimental unit from the time of seedling emergence through inflorescence development using quantum sensors. Growth was defined as the increase in leaf area and leaf number over the duration of the study. Models that fit the data well were developed. A non linear model and two linear models described vegetative growth very well, however the non-linear model would be difficult to use and therefore is not recommended. The model predicting the time to visible bud may support evidence of critical minimum light and time requirements. The model describing the inflorescence development did not fit well as seen in a low R2. Though the models developed generally fit very well, they were based on a very small database. There was no supporting field and greenhouse data to validate the models. For these reasons, the models developed in this study should be used as guides rather than final predictive models

Magnetic Resonance of the Heart

Introduction Cardiovascular magnetic resonance (CMR) is a developing field with enormous potential because of its major attributes of high image quality and resolution combined with non-ionising radiation and versatility. With recent major technological advances, there have been great improvements in acquisition speed and quality that makes the use of CMR in a wide range of cardiac conditions robust and valuable. This article reviews the fundamentals of CMR and its current clinical applications. Fundamentals of Cardiovascular Magnetic Resonance There are essentially three types of imaging sequence that are used in the cardiovascular system: In spin-echo imaging, the blood appears black and good-quality anatomical imaging is obtained. In gradient-echo imaging, the blood is white and the high-quality cine imaging is used to identify regional myocardial function and abnormal flow patterns. The gradient-echo technique of velocity mapping uses the phase of the MR signal to measure velocity; it usually behaves like 2-dimensional Doppler, but unlike Doppler it can measure flow directly and can be extended into seven dimensions for complex flow-dynamics problems For dedicated CMR, the environment typically incorporates medical gases, full invasive and non-invasive physiological monitoring telemetry, stress infusion pumps for adenosine and dobutamine, a power injector for contrast studies, and full resuscitation equipment and drugs. Experience has demonstrated that acutely ill and anaesthetised patients can be safely managed within the magnet in experienced centres. Modern CMR scanners incorporate ultrafast technology that allows real-time imaging (up to 50 frames per second), and ultrafast applications for assessing coronary artery disease (CAD). Currently, most scans are still gated to the electrocardiogram, and in some cases also to the respiratory cycle using advanced diaphragm-monitoring techniques. CMR is as safe as echocardiography. It is also safe for scanning all prosthetic heart valves and for patients with sternal wires, joint replacements, and retained epicardial pacing leads. There is abundant evidence that stents are safe to scan any time after insertion Established Clinical Indications Aorta The aorta is well-imaged by CMR over its entire length. Three-point plane definition techniques are useful for imaging in the long axis of the aorta with reference to points in the ascending and descending limbs and the arch. The 'candy cane' view shows the extent of dissections and the location of coarctation. Closer interrogation of specific regions can also be made with orthogonal planes. CMR has been shown to be more accurate than transoesophageal echocardiography (TE) and computed tomography (CT) in evaluating acute dissection Congenital Heart Disease Echocardiography is ideal for monitoring congenital disease in the young, but with growth into adulthood and after corrective surgery, CMR plays a larger role and is of- IDKD 200

Development of the Density Modified Displacement (DMD) method for efficient recovery of DNAPLS from contaminated aquifers: experimental evaluation and mathematical modeling

Issued as final reportTrac II: Subproject I

Corrigendum to CNTNAP2 variants affect early language development in the general population

Corrigendum to CNTNAP2 variants affect early language development in the general population A. J. O. Whitehouse, D. V. M. Bishop, Q. W. Ang, C. E. Pennell and S. E. Fisher Genes Brain Behav (2011) doi: 10.1111/j.1601-183X.2011.00684.x. The authors have detected a typographical error in the Abstract of this paper. The error is in the fifth sentence, which reads: ‘‘On the basis of these findings, we performed analyses of four-marker haplotypes of rs2710102–rs759178–rs17236239–rs2538976 and identified significant association (haplotype TTAA, P = 0.049; haplotype GCAG,P = .0014).’’ Rather than ‘‘GCAG’’, the final haplotype should read ‘‘CGAG’’. This typographical error was made in the Abstract only and this has no bearing on the results or conclusions of the study, which remain unchanged. Reference Whitehouse, A. J. O., Bishop, D. V. M., Ang, Q. W., Pennell, C. E. & Fisher, S. E. (2011) CNTNAP2 variants affect early language development in the general population. Genes Brain Behav 10, 451–456. doi: 10.1111/j.1601-183X.2011.00684.x

The year in cardiology: imaging. The year in cardiology 2019.

No abstract available

Introduction: Marginalised Histories of the Second World War

This is the final version. Available on open access from Routledge via the DOI in this recordThis special issue, stemming out of the AHRC-funded Teaching and Learning War Research Network (2017–2020), is published at an important juncture in cultural memory: as the focus of public commemorative events in Britain and the Commonwealth shifts from the First to the Second World War, including the Holocaust. Not only does it showcase exciting and cutting-edge research, but it also aims to stimulate conversation and ‘forward-thinking’ about commemorative cycles over the next two-and-a-half decades (2025–2045). The three research articles and four provocations focus, in different ways, on the question of ‘hidden histories’ in the expectation of a need to ensure that diversity, multi-perspectivity, complexity, and contention remain at the heart of ‘national’ commemorative processes (whether in Britain or elsewhere).Arts and Humanities Research Council (AHRC

Cardiovascular magnetic resonance myocardial perfusion: methods and applications in patients with coronary artery disease

Perfusion CMR is an attractive imaging modality that is becoming comparable with other clinically diagnostic tests. SPECT and PET are well clinically validated and have good accuracy for detection of significant CAD. However, these techniques have a rather low spatial resolution and are not suitable for the detection of subendocardial perfusion defect. In addition, the radiation burden, the potential for attenuation artefacts (SPECT) and the limited availability (PET) are limitations of these imaging techniques. An integrated assessment of myocardial perfusion, function and viability is feasible with CMR. In addition, compared to other clinically available imaging techniques, CMR perfusion has excellent spatial resolution and no ionising radiation exposure. However, it is not widely available and there is a need of protocol and pulse sequence standardization. Most perfusion analysis remains observer-dependent (“eyeball” analysis) or dependent on bolus dispersion (semi-quantitative analysis). Fully quantitative analysis using CMR perfusion is currently time-consuming for clinical application. Perfusion CMR is an evolving field with numerous future directions

Conversion of tunneled hemodialysis catheter–consigned patients to arteriovenous fistula

Conversion of tunneled hemodialysis catheter–consigned patients to arteriovenous fistula.ObjectiveDespite their high incidence of complications, costs, morbidity, and mortality, nearly 27% of the chronic hemodialysis (HD) patients are receiving treatment via a tunneled hemodialysis catheter (TDC).MethodsIn this prospective analysis, an interventional nephrology team employed an organized program consisting of vascular access (VA) education and vascular mapping (VM) to TDC-consigned patients. A full range of surgical approaches for arteriovenous fistula (AVF) creation, including vein transpositions, was exercised. Physical examination was performed every 1 to 2 weeks after surgery to assess the development of the AVF. Fistulas that failed to develop adequately to support HD (early failure) underwent salvage [percutaneous transluminal angioplasty (PTA), accessory vein obliteration (AVL)] procedures.ResultsOne hundred twenty-one TDC-consigned patients received VA education. Eighty-six (71%) agreed to undergo VM. Two groups were identified. Group I (N = 66; using TDC for 7.2 ± 1.8 SD months) had never had an arteriovenous access; group II (N = 20; using TDC for 12.3 ± 4.0 months) had a history of one or more previously failed arteriovenous accesses. Upon VM, 64/66 (97%) in group I and 18/20 (90%) in group II were found to have adequate veins for AVF creation. Seven patients (11%) in group I and 3 (17%) in group II refused surgery. In group I, 57 (89%) received an arteriovenous access (radiocephalic AVF = 15, brachiocephalic AVF = 35, transposed brachiobasilic AVF = 3, brachiobasilic AVG = 4). In group II, 15 (83%) received a transposed AVF (radiobasilic = 2, brachiobasilic = 13). Sixteen fistulas (30%) in group I and 8 (53%) in group II had early failure. All except for one fistula in each group were salvaged using PTA and/or AVL. All 70 accesses (AVF = 66, AVG = 4) remain functional, with a mean follow-up of 8.5 ± 3.6 months.ConclusionThese results demonstrate that an organized approach based upon a comprehensive program utilizing VA counseling, VM, application of full range of surgical techniques, and salvage procedures can be very successful in providing optimum vascular access to the catheter-dependent patient

Coronary microvascular ischemia in hypertrophic cardiomyopathy - a pixel-wise quantitative cardiovascular magnetic resonance perfusion study.

BACKGROUND: Microvascular dysfunction in HCM has been associated with adverse clinical outcomes. Advances in quantitative cardiovascular magnetic resonance (CMR) perfusion imaging now allow myocardial blood flow to be quantified at the pixel level. We applied these techniques to investigate the spectrum of microvascular dysfunction in hypertrophic cardiomyopathy (HCM) and to explore its relationship with fibrosis and wall thickness. METHODS: CMR perfusion imaging was undertaken during adenosine-induced hyperemia and again at rest in 35 patients together with late gadolinium enhancement (LGE) imaging. Myocardial blood flow (MBF) was quantified on a pixel-by-pixel basis from CMR perfusion images using a Fermi-constrained deconvolution algorithm. Regions-of-interest (ROI) in hypoperfused and hyperemic myocardium were identified from the MBF pixel maps. The myocardium was also divided into 16 AHA segments. RESULTS: Resting MBF was significantly higher in the endocardium than in the epicardium (mean ± SD: 1.25 ± 0.35 ml/g/min versus 1.20 ± 0.35 ml/g/min, P < 0.001), a pattern that reversed with stress (2.00 ± 0.76 ml/g/min versus 2.36 ± 0.83 ml/g/min, P < 0.001). ROI analysis revealed 11 (31%) patients with stress MBF lower than resting values (1.05 ± 0.39 ml/g/min versus 1.22 ± 0.36 ml/g/min, P = 0.021). There was a significant negative association between hyperemic MBF and wall thickness (β = −0.047 ml/g/min per mm, 95% CI: −0.057 to −0.038, P < 0.001) and a significantly lower probability of fibrosis in a segment with increasing hyperemic MBF (odds ratio per ml/g/min: 0.086, 95% CI: 0.078 to 0.095, P = 0.003). CONCLUSIONS: Pixel-wise quantitative CMR perfusion imaging identifies a subgroup of patients with HCM that have localised severe microvascular dysfunction which may give rise to myocardial ischemia