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1.
Neurochirurgie ; 69(5): 101475, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37544167
2.
Br J Oral Maxillofac Surg ; 59(8): 935-940, 2021 10.
Article in English | MEDLINE | ID: mdl-34400024

ABSTRACT

In 2008, to create a rapid route for information transfer in relation training and recruitment for OMFS trainees, the British Association of Oral and Maxillofacial Surgeons (BAOMS) created a website to "Register Your Interest in OMFS" (RYIO). From 2011 a Mentoring and Support Programme (MSP) was created to provide focussed guidance for trainees aiming for specialty training. This paper reviews the effectiveness and cost of these programmes. Between 2008 and 2020, 1744 individuals used RYIO on 2715 occasions. Of these registrations, 1772 were by dentists, 193 dental students, 589 doctors and 161 medical students. 2354 were from UK and Ireland and 351 from the rest of the world. 188 registrants subsequently became UK OMFS trainees or specialists. All registrants valued the information provided. In response to RYIO trainee feedback the new 'Taste of OMFS 2020' programme was created. The MSP was originally called the Junior Trainee Programme (JTP). The MSP scheme provides a layer of mentorship/support which runs parallel to the medical/dental training post or period of study. Of 180 members of MSP, 72 have obtained specialty training posts in OMFS. There are 88 current members. Full information is available on the BAOMS website www.baoms.org.uk. Reviewing both programmes, participant feedback is excellent with tangible results whilst cost effectiveness is high.


Subject(s)
Mentoring , Surgery, Oral , Humans , Mentors , Oral and Maxillofacial Surgeons , Surveys and Questionnaires , United Kingdom
3.
Rev Sci Instrum ; 92(4): 043520, 2021 Apr 01.
Article in English | MEDLINE | ID: mdl-34243436

ABSTRACT

A machine learning approach has been implemented to measure the electron temperature directly from the emission spectra of a tokamak plasma. This approach utilized a neural network (NN) trained on a dataset of 1865 time slices from operation of the DIII-D tokamak using extreme ultraviolet/vacuum ultraviolet emission spectroscopy matched with high-accuracy divertor Thomson scattering measurements of the electron temperature, Te. This NN is shown to be particularly good at predicting Te at low temperatures (Te < 10 eV) where the NN demonstrated a mean average error of less than 1 eV. Trained to detect plasma detachment in the tokamak divertor, a NN classifier was able to correctly identify detached states (Te < 5 eV) with a 99% accuracy (an F1 score of 0.96) at an acquisition rate 10× faster than the Thomson scattering measurement. The performance of the model is understood by examining a set of 4800 theoretical spectra generated using collisional radiative modeling that was also used to predict the performance of a low-cost spectrometer viewing nitrogen emission in the visible wavelengths. These results provide a proof-of-principle that low-cost spectrometers leveraged with machine learning can be used to boost the performance of more expensive diagnostics on fusion devices and be used independently as a fast and accurate Te measurement and detachment classifier.

4.
Br J Oral Maxillofac Surg ; 59(1): 97-101, 2021 01.
Article in English | MEDLINE | ID: mdl-33168366

ABSTRACT

Following free tissue transfer, intravenous iron (IVI) has a role in reducing the rates of blood transfusion and more rapidly restoring haemoglobin (Hb) levels. Anaemia has a detrimental effect on survival, postoperative complications, fatigue, and health-related quality of life, therefore early correction is recommended. The aim of this re-audit is to assess the use of IVI, of tranexamic acid intraoperatively, and of perioperative blood transfusions. A total of 148 consecutive patients who underwent ablative surgery and free flap reconstruction between May 2018 and September 2019 were audited. The median (IQR) age was 66 (59,72) years and 36% were female. For two-thirds, surgery was for cancer located in the oral cavity and two-thirds of the free flaps were soft tissue. Tranexamic acid (TXA) was used intraoperatively for 30%, red blood cells (RBC) were transfused for 20% and 55 patients (37%) received IV iron. This compares with 4%, 26%, and 0, respectively, in the initial audit. Those having IVI were more likely (56%) to have had a composite flap, a lower postoperative haemoglobin and lower discharge Hb. The Hb between four and twelve weeks' follow up, known for 40, was a median (IQR) of 122 (104,138). There were no adverse reactions to IV iron. Although it is straightforward to administer IVI postoperatively, this re-audit demonstrates that it can be a challenge to embed change in protocols. Through raised awareness of the benefits of IVI, lack of adverse events and clarification of selection criteria, it is hoped that rates of IVI use will increase.


Subject(s)
Anemia, Iron-Deficiency , Antifibrinolytic Agents , Free Tissue Flaps , Tranexamic Acid , Administration, Intravenous , Aged , Anemia, Iron-Deficiency/drug therapy , Antifibrinolytic Agents/therapeutic use , Female , Humans , Iron/therapeutic use , Male , Quality of Life , Tranexamic Acid/therapeutic use
5.
Sci Rep ; 10(1): 17909, 2020 10 21.
Article in English | MEDLINE | ID: mdl-33087822

ABSTRACT

Gene expression analysis is emerging as a new diagnostic tool in transplant pathology, in particular for the diagnosis of antibody-mediated rejection. Diagnostic gene expression panels are defined on the basis of their pathophysiological relevance, but also need to be tested for their robustness across different preservatives and analysis platforms. The aim of this study is the investigate the effect of tissue sampling and preservation on candidate genes included in a renal transplant diagnostic panel. Using the NanoString platform, we compared the expression of 219 genes in 51 samples, split for formalin-fixation and paraffin-embedding (FFPE) and RNAlater preservation (RNAlater). We found that overall, gene expression significantly correlated between FFPE and RNAlater samples. However, at the individual gene level, 46 of the 219 genes did not correlate across the 51 matched FFPE and RNAlater samples. Comparing gene expression results using NanoString and qRT-PCR for 18 genes in the same pool of RNA (RNAlater), we found a significant correlation in 17/18 genes. Our study indicates that, in samples from the same routine diagnostic renal transplant biopsy procedure split for FFPE and RNAlater, 21% of 219 genes of potential biological significance do not correlate in expression. Whether this is due to fixatives or tissue sampling, selection of gene panels for routine diagnosis should take this information into consideration.


Subject(s)
Gene Expression Profiling/methods , Genetic Association Studies/methods , Graft Rejection/diagnosis , Graft Rejection/genetics , Kidney Transplantation , Formaldehyde , Graft Rejection/immunology , Humans , Paraffin Embedding/methods , RNA , Real-Time Polymerase Chain Reaction/methods , Tissue Fixation/methods
6.
BMC Health Serv Res ; 20(1): 814, 2020 Sep 01.
Article in English | MEDLINE | ID: mdl-32867837

ABSTRACT

BACKGROUND: Many women with hyperglycaemia in pregnancy do not receive care during and after pregnancy according to standards recommended in international guidelines. The burden of hyperglycaemia in pregnancy falls disproportionately upon Indigenous peoples worldwide, including Aboriginal and Torres Strait Islander women in Australia. The remote and regional Australian context poses additional barriers to delivering healthcare, including high staff turnover and a socially disadvantaged population with a high prevalence of diabetes. METHODS: A complex health systems intervention to improve care for women during and after a pregnancy complicated by hyperglycaemia will be implemented in remote and regional Australia (the Northern Territory and Far North Queensland). The Theoretical Domains Framework was used during formative work with stakeholders to identify intervention components: (1) increasing workforce capacity, skills and knowledge and improving health literacy of health professionals and women; (2) improving access to healthcare through culturally and clinically appropriate pathways; (3) improving information management and communication; (4) enhancing policies and guidelines; (5) embedding use of a clinical register as a quality improvement tool. The intervention will be evaluated utilising the RE-AIM framework at two timepoints: firstly, a qualitative interim evaluation involving interviews with stakeholders (health professionals, champions and project implementers); and subsequently a mixed-methods final evaluation of outcomes and processes: interviews with stakeholders; survey of health professionals; an audit of electronic health records and clinical register; and a review of operational documents. Outcome measures include changes between pre- and post-intervention in: proportion of high risk women receiving recommended glucose screening in early pregnancy; diabetes-related birth outcomes; proportion of women receiving recommended postpartum care including glucose testing; health practitioner confidence in providing care, knowledge and use of relevant guidelines and referral pathways, and perception of care coordination and communication systems; changes to health systems including referral pathways and clinical guidelines. DISCUSSION: This study will provide insights into the impact of health systems changes in improving care for women with hyperglycaemia during and after pregnancy in a challenging setting. It will also provide detailed information on process measures in the implementation of such health system changes.


Subject(s)
Health Services, Indigenous/organization & administration , Hyperglycemia/therapy , Pregnancy Complications/therapy , Prenatal Care/organization & administration , Adult , Female , Government Programs , Health Personnel , Humans , Hyperglycemia/diagnosis , Mass Screening , Maternal Health Services , Medical Assistance , Native Hawaiian or Other Pacific Islander , Northern Territory , Pregnancy , Pregnancy in Diabetics/diagnosis , Pregnancy in Diabetics/epidemiology , Quality Improvement , Queensland , Referral and Consultation
7.
Phys Chem Chem Phys ; 22(37): 21504-21511, 2020 Sep 30.
Article in English | MEDLINE | ID: mdl-32955064

ABSTRACT

It has recently been demonstrated that N-heterocyclic carbenes (NHCs) form self-assembled monolayers (SAMs) on metal surfaces. Consequently, it is important to both characterize and understand their binding modes to fully exploit NHCs in functional surface systems. To assist with this effort, we have performed first-principles total energy calculations for NHCs on Au(111) and simulations of X-ray absorption near edge structure (XANES). The NHCs we have considered are N,N-dimethyl-, N,N-diethyl-, N,N-diisopropylbenzimidazolylidene (BNHCX, with X = Me, Et, and iPr, respectively) and the bis-BNHCX-Au complexes derived from these molecules. We present a comprehensive analysis of the energetic stability of both the BNHCX and the complexes on Au(111) and, for the former, examine the role of the wing group in determining the attachment geometry. Further structural characterization is performed by calculating the nitrogen K-edge X-ray absorption spectra. Our simulated XANES results give insight into (i) the relationship between the BNHCX/Au geometry and the N(1s) → π*/σ*, pre-edge/near-edge, absorption intensities, and (ii) the contributions of the molecular deformation and molecule-surface electronic interaction to the XANES spectrum. These simulated spectra work not only as a map to the BNHCX conformation, but also, combined with electronic structure calculations, provide a clear understanding of recent experimental XANES findings on BNHCX/Au.

8.
HIV Med ; 21(10): 671-673, 2020 11.
Article in English | MEDLINE | ID: mdl-32741092

ABSTRACT

OBJECTIVES: The aim of the study was to determine whether it is safe to stop secondary prophylaxis in patients with talaromycosis after immune reconstitution with a sustained increase in CD4 count to ≥ 100 cells/µL after antiretroviral therapy (ART). METHODS: A retrospective cohort analysis was performed in HIV-infected patients treated for talaromycosis between June 2009 and June 2017 in Medical Action Myanmar (MAM) clinics. RESULTS: Among a cohort of 5466 HIV-infected patients, 41 patients were diagnosed with and treated for clinical talaromycosis. All the patients were on ART and had a CD4 count < 100 cells/µL. Of these 41 patients, 24 patients (71%) were skin smear positive for talaromycosis, while results were negative in 17 patients. Median CD4 count and haemoglobin concentration were 24 cells/µL and 7.7 g/dL, respectively. Seventy-three per cent (30) were male. Among the 41 patients, 11 (27%) died and six (15%) were transferred to other centres. Twenty-four patients (58% of the total diagnosed) stopped itraconazole secondary prophylaxis after starting active ART with CD4 counts > 100 cells/µL for at least 1 year. Throughout the duration of follow-up post itraconazole cessation, the observed incidence of relapse was zero with a total follow-up of 93.8 person-years (95% confidence interval 0-4 per 100 person-years). The median (25th, 75th percentile) duration of follow-up post-prophylaxis discontinuation was 2.8 (2.1, 6.3) years. CONCLUSIONS: Secondary prophylaxis can be safely stopped in patients with talaromycosis after immune reconstitution with a sustained increase in CD4 count to ≥ 100 cells/µL after highly active antiretroviral therapy.


Subject(s)
Antiretroviral Therapy, Highly Active/methods , HIV Infections/drug therapy , Itraconazole/therapeutic use , Mycoses/drug therapy , Secondary Prevention/methods , Adult , CD4 Lymphocyte Count , Female , HIV Infections/immunology , Humans , Male , Myanmar , Mycoses/immunology , Retrospective Studies , Treatment Outcome
9.
Proc Biol Sci ; 287(1929): 20200562, 2020 06 24.
Article in English | MEDLINE | ID: mdl-32546097

ABSTRACT

Many microbial symbionts have multiple phenotypic consequences for their animal hosts. However, the ways in which different symbiont-mediated phenotypes combine to affect fitness are not well understood. We investigated whether there are correlations between different symbiont-mediated phenotypes. We used the symbiont Spiroplasma, a striking example of a bacterial symbiont conferring diverse phenotypes on insect hosts. We took 11 strains of Spiroplasma infecting pea aphids (Acyrthosiphon pisum) and assessed their ability to provide protection against the fungal pathogen Pandora neoaphidis and the parasitoids Aphidius ervi and Praon volucre. We also assessed effects on male offspring production for five of the Spiroplasma strains. All but one of the Spiroplasma strains provided very strong protection against the parasitoid P. volucre. As previously reported, variable protection against P. neoaphidis and A. ervi was also present; male-killing was likewise a variable phenotype. We find no evidence of any correlation, positive or negative, between the different phenotypes, nor was there any evidence of an effect of symbiont phylogeny on protective phenotype. We conclude that multiple symbiont-mediated phenotypes can evolve independently from one another without trade-offs between them.


Subject(s)
Aphids/microbiology , Spiroplasma/physiology , Animals , Biological Evolution , Phenotype , Symbiosis
10.
Trends Microbiol ; 28(8): 597-600, 2020 08.
Article in English | MEDLINE | ID: mdl-32359782

ABSTRACT

Measles vaccination is a public health 'best buy', with the highest cost of illness averted of any vaccine-preventable disease (Ozawa et al., Bull. WHO 2017;95:629). In recent decades, substantial reductions have been made in the number of measles cases, with an estimated 20 million deaths averted from 2000 to 2017 (Dabbagh et al., MMWR 2018;67:1323). Yet, an important feature of epidemic dynamics is that large outbreaks can occur following years of apparently successful control (Mclean et al., Epidemiol. Infect. 1988;100:419-442). Such 'post-honeymoon period' outbreaks are a result of the nonlinear dynamics of epidemics (Mclean et al., Epidemiol. Infect. 1988;100:419-442). Anticipating post-honeymoon outbreaks could lead to substantial gains in public health, helping to guide the timing, age-range, and location of catch-up vaccination campaigns (Grais et al., J. Roy. Soc. Interface 2008003B6:67-74). Theoretical conditions for such outbreaks are well understood for measles, yet the information required to make these calculations policy-relevant is largely lacking. We propose that a major extension of serological studies to directly characterize measles susceptibility is a high priority.


Subject(s)
Disease Susceptibility/epidemiology , Mass Vaccination/statistics & numerical data , Measles Vaccine/immunology , Measles/epidemiology , Antibodies, Viral/blood , Disease Outbreaks , Humans , Public Health , Serologic Tests
11.
Ann Intensive Care ; 10(1): 49, 2020 Apr 25.
Article in English | MEDLINE | ID: mdl-32335780

ABSTRACT

BACKGROUND: The echocardiography working group of the European Society of Intensive Care Medicine recognized the need to provide structured guidance for future CCE research methodology and reporting based on a systematic appraisal of the current literature. Here is reported this systematic appraisal. METHODS: We conducted a systematic review, registered on the Prospero database. A total of 43 items of common interest to all echocardiography studies were initially listed by the experts, and other "topic-specific" items were separated into five main categories of interest (left ventricular systolic function, LVSF n = 15, right ventricular function, RVF n = 18, left ventricular diastolic function, LVDF n = 15, fluid management, FM n = 7, and advanced echocardiography techniques, AET n = 17). We evaluated the percentage of items reported per study and the fraction of studies reporting a single item. RESULTS: From January 2000 till December 2017 a total of 209 articles were included after systematic search and screening, 97 for LVSF, 48 for RVF, 51 for LVDF, 36 for FM and 24 for AET. Shock and ARDS were relatively common among LVSF articles (both around 15%) while ARDS comprised 25% of RVF articles. Transthoracic echocardiography was the main echocardiography mode, in 87% of the articles for AET topic, followed by 81% for FM, 78% for LVDF, 70% for LVSF and 63% for RVF. The percentage of items per study as well as the fraction of study reporting an item was low or very low, except for FM. As an illustration, the left ventricular size was only reported by 56% of studies in the LVSF topic, and half studies assessing RVF reported data on pulmonary artery systolic pressure. CONCLUSION: This analysis confirmed sub-optimal reporting of several items listed by an expert panel. The analysis will help the experts in the development of guidelines for CCE study design and reporting.

12.
Br J Oral Maxillofac Surg ; 57(10): 1119-1125, 2019 12.
Article in English | MEDLINE | ID: mdl-31672256

ABSTRACT

Radiotherapy-induced xerostomia (RIX) is a common and untreatable side effect of radiotherapy to the head and neck. Visco-ease™ mouth spray (Lamellar Biomedical Ltd), a new product that is made from lamellar body mimetics, reduces the viscosity of saliva ex vivo. The purpose of this study was to evaluate its safety and effectiveness in the treatment of RIX in 43 patients with cancer of the head and neck. They were randomised into the Visco-ease™ or placebo groups, and asked to complete the Groningen radiotherapy-induced xerostomia (GRIX) questionnaire each week. The primary endpoint was a change in GRIX score from baseline to end of treatment. There was no difference in scores between the two groups, and none of the patients had device-related serious adverse events. Visco-ease™ oral spray was safe and tolerable but no better than placebo in reducing RIX in this group of patients.


Subject(s)
Head and Neck Neoplasms , Oral Sprays , Radiation Injuries , Xerostomia , Double-Blind Method , Head and Neck Neoplasms/radiotherapy , Humans , Radiation Injuries/prevention & control , Saliva , Xerostomia/prevention & control
13.
Res Vet Sci ; 126: 213-226, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31610472

ABSTRACT

Multiple births or twinning in equids are dangerous, undesirable situations that compromise the life of the dam and resulting offspring. However, embryo vitrification and freezing techniques take advantage of individuals whose multiple ovulations allow flushing more fertilised embryos from the oviduct to be collected, increasing the productivity and profitability of reproductive techniques. Embryo preservation is especially important in highly endangered populations such as certain donkey (Equus asinus) breeds; for which conventional reproductive techniques have previously been deemed inefficient. For instance, becoming an effective alternative to artificial insemination with frozen semen to preserve the individuals' genetic material. The objective of this study was to examine the historical foaling records of Andalusian donkeys to estimate prevalence, risk factors, phenotypic and genetic parameters for multiple births, assessing the cumulative foal number born per animal, maximum foal number per birth and multiple birth number per animal. We designed a Bayesian General Animal Mixed Model with single records considering the 'fixed' effects of birth year, birth season, birth month, sex, farm, location, and husbandry system. Age was considered and included as a linear and quadratic covariate. Gibbs sampling reported heritability estimates ranging from 0.18 ±â€¯0.101 to 0.24 ±â€¯0.078. Genetic and phenotypic correlations ranged from 0.496 ±â€¯0.298 to 0.846 ±â€¯0.152 and 0.206 ±â€¯0.063 to 0.607 ±â€¯0.054, respectively. Predicted breeding values obtained enable the potential selection against/for these traits, offering a new perspective for donkey breeding and conservation.


Subject(s)
Equidae/physiology , Fertility/genetics , Heredity , Litter Size/genetics , Multiple Birth Offspring/genetics , Animals , Bayes Theorem , Endangered Species , Equidae/genetics , Female , Male , Models, Genetic , Risk Factors
14.
Intensive Care Med ; 45(6): 911, 2019 Jun.
Article in English | MEDLINE | ID: mdl-30989263

ABSTRACT

The original version of this article unfortunately contained a mistake.

15.
Intensive Care Med ; 45(6): 770-788, 2019 06.
Article in English | MEDLINE | ID: mdl-30911808

ABSTRACT

INTRODUCTION: This narrative review focusing on critical care echocardiography (CCE) has been written by a group of experts in the field, with the aim of outlining the state of the art in CCE in the 10 years after its official recognition and definition. RESULTS: In the last 10 years, CCE has become an essential branch of critical care ultrasonography and has gained general acceptance. Its use, both as a diagnostic tool and for hemodynamic monitoring, has increased markedly, influencing contemporary cardiorespiratory management. Recent studies suggest that the use of CCE may have a positive impact on outcomes. CCE may be used in critically ill patients in many different clinical situations, both in their early evaluation of in the emergency department and during intensive care unit (ICU) admission and stay. CCE has also proven its utility in perioperative settings, as well as in the management of mechanical circulatory support. CCE may be performed with very simple diagnostic objectives. This application, referred to as basic CCE, does not require a high level of training. Advanced CCE, on the other hand, uses ultrasonography for full evaluation of cardiac function and hemodynamics, and requires extensive training, with formal certification now available. Indeed, recent years have seen the creation of worldwide certification in advanced CCE. While transthoracic CCE remains the most commonly used method, the transesophageal route has gained importance, particularly for intubated and ventilated patients. CONCLUSION: CCE is now widely accepted by the critical care community as a valuable tool in the ICU and emergency department, and in perioperative settings.


Subject(s)
Critical Care/trends , Echocardiography/trends , Critical Care/methods , Echocardiography/methods , Hemodynamics/physiology , Humans , Intensive Care Units/organization & administration , Intensive Care Units/trends
16.
Rev Sci Instrum ; 89(10): 10C111, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30399780

ABSTRACT

Translatable in-vessel mirrors have enabled the DIII-D Thomson scattering system to diagnose the divertor plasma in high triangularity shaped plasmas. Previous divertor Thomson scattering measurements in DIII-D were restricted to spatial locations along a Nd:YAG laser beam that was directed through a vertical port. This only allowed measurements to be made in low triangularity shaped plasmas. The new mirrors re-route the laser underneath floor tiles to a position of smaller major radius as necessary for high triangularity plasmas. New in-vessel collection optics transmit scattered light from regions inaccessible to external lenses. Damage to mirrors and high stray light levels are challenges that were overcome to successfully make these measurements. Through the careful use of baffles and light shields, stray light leakage into polychromator detector channels was reduced to negligible levels, allowing temperature measurements below 1 eV. The system is described and the initial results presented.

17.
Rev Sci Instrum ; 89(10): 10J122, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30399945

ABSTRACT

A novel type of surface eroding thermocouple (SETC) has been tested and demonstrated in the small angle slot (SAS) divertor of DIII-D for fast local heat flux measurements. The thermojunction of the SETC is formed between two thin (10 µm) ribbons, which are filed over to create microfiber junctions. These thermocouples are able to be exposed directly to the plasma at surface temperatures exceeding 2000 °C and are capable of sub-10 ms time resolution. Before installation in SAS, the SETCs were exposed in the lower DIII-D divertor during L-mode and H-mode discharges, from which results are presented. In preliminary tests, SETCs proved to be a qualified diagnostic to accurately measure both the intra-edge localized mode (ELM) and inter-ELM heat flux during H-mode shots with high frequency ELMs (hundreds of Hz) and to resolve heat flux profiles during strike point sweeps. The heat fluxes measured by using SETCs are consistent with the heat fluxes measured by using IR cameras and Langmuir probes. These new diagnostic capabilities will complement the existing IR camera measurements and will be of particularly significant value to measure surface heat flux in the SAS divertor or other regions where the IR camera lacks line of sight.

18.
Rev Sci Instrum ; 89(9): 093502, 2018 Sep.
Article in English | MEDLINE | ID: mdl-30278733

ABSTRACT

Coherence Imaging Spectroscopy (CIS) has emerged as a powerful tool for investigating complex ion phenomena in the boundary of magnetically confined plasma devices. The combination of Fourier-transform interferometry and high-resolution fast-framing cameras has made it possible to make sensitive velocity measurements that are also spatially resolved. However, this sensitivity makes the diagnostic vulnerable to environmental effects including thermal drifts, vibration, and magnetic fields that can influence the velocity measurement. Additionally, the ability to provide an absolute calibration for these geometries can be impacted by differences in the light-collection geometry between the plasma and reference light source, spectral impurities, and the presence of thin-films on in-vessel optics. This paper discusses the mitigation of these effects and demonstration that environmental effects result in less than 0.5 km/s error on the DIII-D CIS systems. A diagnostic comparison is used to demonstrate agreement between CIS and traditional spectroscopy once tomographic artifacts are accounted for.

19.
Phys Rev Lett ; 121(7): 075001, 2018 Aug 17.
Article in English | MEDLINE | ID: mdl-30169054

ABSTRACT

A bifurcative step transition from low-density, high-temperature, attached divertor conditions to high-density, low-temperature, detached divertor conditions is experimentally observed in DIII-D tokamak plasmas as density is increased. The step transition is only observed in the high confinement mode and only when the B×∇B drift is directed towards the divertor. This work reports for the first time a theoretical explanation and numerical simulations that qualitatively reproduce this bifurcation and its dependence on the toroidal field direction. According to the model, the bifurcation is primarily driven by the interdependence of the E×B-drift fluxes, divertor electric potential structure, and divertor conditions. In the attached conditions, strong potential gradients in the low field side (LFS) divertor drive E×B-drift flux towards the high field side divertor, reinforcing low density, high temperature conditions in the LFS divertor leg. At the onset of detachment, reduction in the potential gradients in the LFS divertor leg reduce the E×B-drift flux as well, such that the divertor plasma evolves nonlinearly to high density, strongly detached conditions. Experimental estimates of the E×B-drift fluxes, based on divertor Thomson scattering measurements, and their dependence on the divertor conditions are qualitatively consistent with the numerical predictions. The implications for divertor power exhaust and detachment control in the next step fusion devices are discussed.

20.
Ann Emerg Med ; 71(1): 109-112, 2018 Jan.
Article in English | MEDLINE | ID: mdl-28559035

ABSTRACT

The simultaneous use of 2 external defibrillators to administer either dual or sequential cardioversion or defibrillation for refractory cardiac arrhythmias is increasing in both the out-of-hospital and inhospital settings. Using 2 defibrillators to administer higher energy levels than can be achieved with a single defibrillator is considered off-label and is currently not part of published advanced cardiac life support guidelines. We report the first case in which the use of dual-dose cardioversion was associated with external defibrillator damage. Because defibrillator damage, especially if undetected, jeopardizes patient safety and off-label medical product use may void the manufacturer's warranty, this case should urge users to proceed with caution when contemplating this technique.


Subject(s)
Defibrillators , Electric Countershock/instrumentation , Equipment Failure , Tachycardia, Ventricular/therapy , Adult , Electric Countershock/methods , Humans , Male
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