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1.
Rev Sci Instrum ; 95(6)2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38921059

ABSTRACT

Superconducting magnets based on Rare Earth Barium Copper Oxides (REBCO) offer transformative capabilities in the fields of fusion energy, high energy physics, and space exploration. A challenge shared by these applications is the limited lifetime of REBCO due to radiation damage sustained during operation. Here we present a new ion-beam facility that enables simultaneous cryogenic irradiation and in situ characterization of commercial REBCO tapes. The ion source provides spatially uniform fluxes up to 1018 protons/m2s with kinetic energies up to 3.4 MeV, in addition to helium and higher-Z species. Using this facility, we can induce uniform damage profiles in the first 10-20 µm of REBCO tapes with less than 0.25 appm of hydrogen implanted in REBCO after a dose of 1020 protons/m2. The tape can be held between 20 and 300 K with an accuracy of ±0.1 K and is connected to a four-point probe measuring the critical current, Ic, and critical temperature, Tc, before, during, and after irradiation with transport current ranging from 100 nA to 100 A, and a typical voltage noise less than 0.1 µV. These capabilities are presently used to study the effect of irradiation temperature on REBCO performance change during and after proton bombardment, to assess the possibility of Ic and Tc recovery after irradiation through thermal annealing, and to explore the instantaneous and recoverable suppression of Ic and Tc observed during irradiation.

2.
Rev Sci Instrum ; 89(10): 10J106, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30399747

ABSTRACT

Plasma facing component (PFC) conditioning dramatically affects plasma performance in magnetic confinement fusion experiments. Lithium (Li) has been used in several machines to condition PFC with subsequent improvements to plasma performance. Multiple studies have investigated the interactions of Li with deuterium (D) and oxygen (O) in order to ascertain the mechanisms behind the enhanced plasma performance. Ion Beam Analysis (IBA) is a useful tool to interrogate PFC surfaces as they interact with plasmas. Dynamics of ion implantation and sputtering of surfaces (DIONISOS) is a linear plasma device, capable of generating discharges with fluxes ∼1021 m-2 s-1 and Te ∼6 eV, coupled to an ion accelerator. DIONISOS is capable of analyzing samples using Elastic Recoil Detection (ERD) and Rutherford Backscattering Spectroscopy (RBS) during plasma exposures. The facility has been equipped with a Li deposition system for evaporation of thin coatings on different substrates. The evaporator enables real time ERD and RBS measurements of deposition and erosion of Li coatings on different substrates and the interaction of the Li with the vacuum and plasma. Considerations for ERD, e.g., ion species, energy, and data acquisition frequency, are presented. This work is the basis for further investigation of He, H, and D retention in solid and liquid Li.

3.
Rev Sci Instrum ; 85(2): 023503, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24593357

ABSTRACT

A major impediment towards a better understanding of the complex plasma-surface interaction is the limited diagnostic access to the material surface while it is undergoing plasma exposure. The Dynamics of ION Implantation and Sputtering Of Surfaces (DIONISOS) experiment overcomes this limitation by uniquely combining powerful, non-perturbing ion beam analysis techniques with a steady-state helicon plasma exposure chamber, allowing for real-time, depth-resolved in situ measurements of material compositions during plasma exposure. Design solutions are described that provide compatibility between the ion beam analysis requirements in the presence of a high-intensity helicon plasma. The three primary ion beam analysis techniques, Rutherford backscattering spectroscopy, elastic recoil detection, and nuclear reaction analysis, are successfully implemented on targets during plasma exposure in DIONISOS. These techniques measure parameters of interest for plasma-material interactions such as erosion/deposition rates of materials and the concentration of plasma fuel species in the material surface.

4.
Int J Sports Med ; 35(9): 725-30, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24577860

ABSTRACT

This study examined the effect of exercise-induced dehydration by ~4% body mass loss on 5-km cycling time trial (TT) performance and neuromuscular drive, independent of hyperthermia. 7 active males were dehydrated on 2 occasions, separated by 7 d. Participants remained dehydrated (DEH, -3.8±0.5%) or were rehydrated (REH, 0.2±0.6%) over 2 h before completing the TT at 18-25 °C, 20-30% relative humidity. Neuromuscular function was determined before dehydration and immediately prior the TT. The TT started at the same core temperature (DEH, 37.3±0.3°C; REH, 37.0±0.2 °C (P>0.05). Neither TT performance (DEH, 7.31±1.5 min; REH, 7.10±1.3 min (P>0.05)) or % voluntary activation were affected by dehydration (DEH, 88.7±6.4%; REH, 90.6±6.1% (P>0.05)). Quadriceps peak torque was significantly elevated in both trials prior to the TT (P<0.05), while a 19% increase in the rate of potentiated peak twitch torque development (P<0.05) was observed in the DEH trial only. All other neuromuscular measures were similar between trials. Short duration TT performance and neuromuscular function are not reduced by dehydration, independent of hyperthermia.


Subject(s)
Athletic Performance/physiology , Bicycling/physiology , Dehydration/physiopathology , Muscle, Skeletal/physiology , Adult , Body Mass Index , Body Temperature/physiology , Exercise Test , Fluid Therapy , Humans , Male , Muscle Contraction/physiology , Muscle, Skeletal/innervation , Task Performance and Analysis , Time Factors , Young Adult
5.
Rev Sci Instrum ; 84(5): 053507, 2013 May.
Article in English | MEDLINE | ID: mdl-23742551

ABSTRACT

A new Ion Sensitive Probe head has been created for the outer-midplane scanning probe system on the Alcator C-Mod tokamak. The new probe head contains three elements: an ion sensitive probe to measure ion temperature and plasma potential, a Langmuir probe to measure electron temperature, density, and floating potential, and a second Langmuir probe to measure ion saturation current and the density fluctuations arising from ''blob'' events. The ion sensitive probe current is normalized to this measurement to reduced deleterious effects of the strong fluctuations. Design of the high heat flux probe (>100 MW/m(2)) and initial results are presented.

6.
Rev Sci Instrum ; 84(3): 033502, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23556816

ABSTRACT

A new Retarding Field Analyzer (RFA) head has been created for the outer-midplane scanning probe system on the Alcator C-Mod tokamak. The new probe head contains back-to-back retarding field analyzers aligned with the local magnetic field. One faces "upstream" into the field-aligned plasma flow and the other faces "downstream" away from the flow. The RFA was created primarily to benchmark ion temperature measurements of an ion sensitive probe; it may also be used to interrogate electrons. However, its construction is robust enough to be used to measure ion and electron temperatures up to the last-closed flux surface in C-Mod. A RFA probe of identical design has been attached to the side of a limiter to explore direct changes to the boundary plasma due to lower hybrid heating and current drive. Design of the high heat flux (>100 MW∕m(2)) handling probe and initial results are presented.

7.
Phys Rev Lett ; 106(21): 215001, 2011 May 27.
Article in English | MEDLINE | ID: mdl-21699305

ABSTRACT

Intrinsic rotation has been observed in I-mode plasmas from the C-Mod tokamak, and is found to be similar to that in H mode, both in its edge origin and in the scaling with global pressure. Since both plasmas have similar edge ∇T, but completely different edge ∇n, it may be concluded that the drive of the intrinsic rotation is the edge ∇T rather than ∇P. Evidence suggests that the connection between gradients and rotation is the residual stress, and a scaling for the rotation from conversion of free energy to macroscopic flow is calculated.

8.
Rev Sci Instrum ; 81(10): 10E106, 2010 Oct.
Article in English | MEDLINE | ID: mdl-21033971

ABSTRACT

The ideal in situ plasma facing component (PFC) diagnostic for magnetic fusion devices would perform surface element and isotope composition measurements on a shot-to-shot (∼10 min) time scale with ∼1 µm depth and ∼1 cm spatial resolution over large areas of PFCs. To this end, the experimental adaptation of the customary laboratory surface diagnostic--nuclear scattering of MeV ions--to the Alcator C-Mod tokamak is being guided by ACRONYM, a Geant4 synthetic diagnostic. The diagnostic technique and ACRONYM are described, and synthetic measurements of film thickness for boron-coated PFCs are presented.

9.
Rev Sci Instrum ; 81(10): 10E111, 2010 Oct.
Article in English | MEDLINE | ID: mdl-21033976

ABSTRACT

An ion sensitive probe (ISP) is developed as a robust diagnostic for measuring plasma potentials (Φ(P)) in magnetized plasmas. The ISP relies on the large difference between the ion and electron gyroradii (ρ(i)/ρ(e)∼60) to reduce the electron collection at a collector recessed behind a separately biased wall distance ∼ρ(i). We develop a new ISP method to measure the plasma potential that is independent of the precise position and shape of the collector. Φ(P) is found as the wall potential when charged current to the probe collector vanishes during the voltage sweep. The plasma potentials obtained from the ISP match Φ(P) measured with an emissive probe over a wide range of plasma conditions in a small magnetized plasma.

10.
Curr Oncol ; 16(3): 8-20, 2009 May.
Article in English | MEDLINE | ID: mdl-19526080

ABSTRACT

The role of taxanes in the treatment of breast cancer is becoming increasingly important. In clinical practice, the taxanes are now standard therapy in both early-stage and metastatic breast cancer. Since the 1990s, multiple randomized clinical trials have been evaluating the efficacy of taxanes in the treatment of metastatic breast cancer. These trials have included treatment with taxanes alone or in combination with other chemotherapeutic agents. Pre-existing published guidelines for the use of taxanes in the management of metastatic breast cancer are available. The mandate of the Alberta Cancer Board Provincial Breast Tumour Group Guideline Panel was to consider and adapt the recommendations of the existing guidelines and to develop de novo guidelines to account for current evidence. For this task, the panel used the ADAPTE process, which is a systematic process of guideline adaptation developed by the ADAPTE Collaboration.The recommendations formulated by the panel included the identification of taxane regimens that could be offered in anthracycline-naïve patients, anthracycline-pretreated or -resistant patients, and patients overexpressing the human epidermal growth factor receptor 2. Potential toxicities and benefits in terms of time to progression, progression-free survival, overall survival, and quality of life were also considered.

11.
Rev Sci Instrum ; 80(4): 043501, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19405654

ABSTRACT

A probe has been designed, constructed, and successfully used to inject methane into the DIII-D lower divertor in a manner imitating natural release by chemical erosion. This porous plug injector (PPI) probe consists of a self-contained gas reservoir with an integrated pressure gauge and a 3 cm diameter porous surface through which gas is injected into the lower divertor of the tokamak. The probe is positioned flush with the divertor target surface by means of the divertor materials evaluation system. Two gas delivery systems were developed: in the first, gas flow is regulated by a remotely controlled microvalve and in the second by a fixed micro-orifice flow restrictor. Because of the large area of the porous surface through which gas is admitted, the injected hydrocarbon molecules see a local carbon surface (>90% carbon) similar to that seen by hydrocarbons being emitted by chemical sputtering from surrounding carbon tiles. The distributed gas source also reduces the disturbance to the local plasma while providing sufficient signal for spectroscopic detection. In situ spectroscopic measurements with the PPI in DIII-D allow the direct calibration of response for measured plasma conditions from a known influx of gas.

12.
Euro Surveill ; 14(16)2009 Apr 23.
Article in English | MEDLINE | ID: mdl-19389339

ABSTRACT

Mumps is a contagious vaccine-preventable viral disease that is experiencing a revival in students attending second and third level colleges. Large mumps outbreaks have been reported in several countries despite the presence of childhood immunisation programmes over many years, including measles, mumps, and rubella (MMR) vaccination. In 2008, 1,377 cases of mumps were notified in Ireland and 1,734 in the first three months of 2009 (provisional data). This paper reviews the recent epidemiology of mumps in the Mid-West region of Ireland and highlights preventive measures. A substantial proportion of cases were not laboratory-confirmed and it is important that doctors continue to notify suspected cases. In the Irish Mid-West, data from enhanced surveillance shows a high proportion of mumps in the age group 15-24 years. Complications were uncommon and rarely severe. Where data were available, over half of the cases did not recall having received two doses of MMR, but most recalled one dose. Parents should continue to ensure children receive both MMR vaccinations so that uptake is optimal for protection. Steps were taken to increase awareness of the disease in the school, college and university settings. Preventive measures implemented to limit mumps transmission in the school/college setting over recent years included vaccination of close contacts, isolation for five days and hand hygiene.


Subject(s)
Mumps/epidemiology , Students , Universities/trends , Humans , Ireland/epidemiology , Mumps/prevention & control , Mumps Vaccine/therapeutic use , Students/statistics & numerical data , Universities/statistics & numerical data
13.
Clin Exp Pharmacol Physiol ; 35(5-6): 701-5, 2008 May.
Article in English | MEDLINE | ID: mdl-18067594

ABSTRACT

1. Many mammals maintain a constant core body temperature in the face of a heat load by using evaporative cooling responses, such as sweating, panting and spreading of saliva. These cooling mechanisms incur a body fluid deficit if the fluid lost as sweat, saliva or respiratory moisture is not replaced by the ingestion of water; body fluid hypertonicity and hypovolaemia result. 2. Evidence in several mammals shows that, as they become dehydrated, evaporative cooling mechanisms such as sweating and panting are inhibited so that further fluid loss from the body is reduced. As a result, core temperature in the dehydrated animal is maintained at a higher than normal level. 3. Increasing the osmotic pressure of plasma has an inhibitory effect on panting and sweating in mammals. It has been proposed that osmoreceptors mediate these inhibitory influences of plasma hypertonicity on sweating and panting. 4. The suppression of panting in dehydrated sheep is mediated by cerebral osmoreceptors that are probably located in the lamina terminalis. We speculate that osmoreceptors in the lamina terminalis may also influence thermoregulatory sweating. 5. When dehydrated animals drink water, sweating and panting resume rapidly before water has been absorbed from the gut. It is likely that the act of drinking initiates a reflex that can override the osmoreceptor inhibition of panting, resulting in core temperature falling back quickly to a normal level.


Subject(s)
Body Temperature Regulation/physiology , Mammals/physiology , Water-Electrolyte Balance/physiology , Animals , Dehydration , Drinking , Homeostasis , Humans , Water/metabolism
14.
Euro Surveill ; 12(10): E13-4, 2007 Oct 01.
Article in English | MEDLINE | ID: mdl-17997925

ABSTRACT

Genital Chlamydia trachomatis (GCT) infection is the most common bacterial sexually transmitted infection (STI) in Ireland. A retrospective analysis of 2,087 laboratory-confirmed GCT patient episodes from 2001 to 2006 in the Mid-West of Ireland was undertaken in conjunction with statutorily notifiable data that were reported by the Sexually Transmitted Disease/Genito-Urinary Medicine (STD/GUM) services in the region and used in national surveillance. Data were analysed by year, source, sex and age. The annual incidence of GCT in the Mid-West is increasing. A substantial proportion of GCT infections were diagnosed in the non-STD/GUM setting. The issue of sexually active young people seeking STI screening is a sensitive one, and delays increase the potential for transmission and the possibility of long-term complications when the disease is not treated. Based on this sample, national surveillance would significantly underestimate the burden of disease in Ireland, due to under-reporting. This would have implications for any national chlamydia screening programme. Among those who sought testing, women aged 15 to 19 years are five times more likely to be found positive than men in the same age group. Of those diagnosed in the non-STD/GUM setting, 83% were women. General practitioners and clinicians might consider targeting those aged 15 to 29 years for opportunistic screening and sexual health advice. Contact tracing and follow-up in the non-STD/GUM setting, as well as access for general practitioners to ongoing education on STIs are challenges to be addressed.


Subject(s)
Chlamydia Infections/diagnosis , Chlamydia Infections/epidemiology , Disease Outbreaks/statistics & numerical data , Population Surveillance/methods , Risk Assessment/methods , Adolescent , Adult , Age Distribution , Chlamydia Infections/microbiology , Female , Humans , Incidence , Ireland/epidemiology , Male , Netherlands/epidemiology , Risk Factors , Sex Distribution
15.
Euro Surveill ; 12(7): E11-2, 2007 Jul 01.
Article in English | MEDLINE | ID: mdl-17991406

ABSTRACT

An outbreak of gastrointestinal disease (nausea, vomiting or diarrhoea) occurred among a party of wedding guests, staff and other guests in a hotel in the west of Ireland, in October 2006. Upon notification, a multi-disciplinary outbreak control team was convened to investigate and control the outbreak. In all, 98 people were ascertained ill. The median duration of illness was 48 hours. The attack rate ranged between 48 and 85%. The hotel voluntarily notified health authorities and co-operated fully with investigation and control measures. Strict prevention and control measures were instituted promptly, including air ventilation, enhanced hand hygiene, isolation of cases, temporary "cooked food only", temporary alternative accommodation and specialised cleaning. Three cases of norovirus infection were laboratory-confirmed. There was no evidence of food- or water-borne transmission. Clinical and epidemiological findings indicated person-to-person transmission of norovirus. This report highlights the potential for large social gatherings to facilitate the spread of viral gastroenteritis by person-to-person transmission and via contaminated environment. Effective community management of this outbreak appears to have prevented its having an impact on local acute hospital services. The authors conclude that in addition to the existing national guidelines on the management of outbreaks of norovirus in healthcare settings, agreed guidelines for the management of norovirus outbreaks in the hotel and tourism industry are needed in Ireland.


Subject(s)
Caliciviridae Infections/epidemiology , Disease Outbreaks/statistics & numerical data , Gastroenteritis/epidemiology , Norovirus/isolation & purification , Population Surveillance , Risk Assessment/methods , Travel , Adolescent , Adult , Aged , Aged, 80 and over , Caliciviridae Infections/microbiology , Caliciviridae Infections/prevention & control , Child , Child, Preschool , Disease Outbreaks/prevention & control , Female , Gastroenteritis/microbiology , Gastroenteritis/prevention & control , Humans , Incidence , Infant , Ireland/epidemiology , Male , Middle Aged , Risk Factors
17.
Ir Med J ; 98(9): 278-80, 2005 Oct.
Article in English | MEDLINE | ID: mdl-16300109

ABSTRACT

Human brucellosis remains a serious public health issue in Ireland. Clinical notifications in the Mid-Western Area (HSE-MWA) underestimate the burden of illness and attendant morbidity in the region. The diagnosis of acute and chronic human brucellosis depends on the clinical evidence and the results from laboratory serological testing or culture on rare occasion. This study examined the clinical evidence behind locally defined serological "positives" in the HSE-MWA from 2002 to 2003. Ninety cases were detected in 2002 and 31 in 2003. While sampling bias is likely to be present, aspects of brucellosis in Ireland were confirmed. Middle-aged males were most commonly affected. The majority of cases were linked to farming or veterinary practice. Symptoms such as sweats, fever and weight loss were commonly associated with acute brucellosis infection while malaise was common in acute and chronic brucellosis. A clear definition of what is notifiable is needed. Surveillance systems must appreciate the importance of both clinical and laboratory evidence to classify confirmed or probable brucellosis as paired sera were not common. Public health authorities must follow-up the clinical aspects for accurate national statistics. General practitioners in the Mid-West appear to be vigilant regarding brucellosis in their patients. Regional zoonoses committees are useful in monitoring disease prevalence in human and animal populations without compromising confidentiality.


Subject(s)
Brucellosis/epidemiology , Adolescent , Adult , Aged , Aged, 80 and over , Brucellosis/diagnosis , Female , Humans , Ireland/epidemiology , Male , Middle Aged , Surveys and Questionnaires
18.
Euro Surveill ; 10(5): 75-7, 2005 May.
Article in English | MEDLINE | ID: mdl-16077206

ABSTRACT

Concerns about healthcare-associated infections and the global crisis in antimicrobial resistance has combined to accentuate the fears around so-called "superbugs". In Ireland there is no single agreed indicator regarded as a true measure of the level of methicillin resistant Staphylococcus aureus (MRSA) in hospitals. The objective of this study was to compare two crude measures of MRSA--the percentage of bacteraemia caused by MRSA and the incidence rate (per 1000 bed days used) of MRSA bacteraemia in six acute hospitals. We examined all blood cultures positive for S. aureus (methicillin sensitive and resistant) from 2002 to 2004 in the Health Service Executive (HSE) Mid-Western Area of Ireland. Hospital In-Patient Enquiry (HIPE) data was used to determine monthly in-patient bed days used. Of 245 patient episodes of bacteraemia, 119 were MRSA. The trends in the percentage of isolates that were MRSA and the incidence rate calculated were compared. The incidence rate appears to be a more reliable and robust indicator of MRSA in hospitals than the percentage. Despite many difficulties in interpreting indicators of MRSA they should not preclude the regular publication of data at least at regional level in Ireland.


Subject(s)
Bacteremia/diagnosis , Bacteremia/epidemiology , Cross Infection/epidemiology , Methicillin Resistance , Risk Assessment/methods , Staphylococcal Infections/epidemiology , Staphylococcus aureus/isolation & purification , Acute Disease , Bacteremia/blood , Bacteremia/microbiology , Critical Care/statistics & numerical data , Hospitalization/statistics & numerical data , Humans , Incidence , Ireland/epidemiology , Population Surveillance/methods , Reproducibility of Results , Risk Factors , Sensitivity and Specificity , Staphylococcal Infections/blood , Staphylococcal Infections/microbiology
19.
Eur J Clin Microbiol Infect Dis ; 24(7): 480-3, 2005 Jul.
Article in English | MEDLINE | ID: mdl-15977004

ABSTRACT

Presented here is the 5-year impact of a national antimicrobial resistance surveillance system in Ireland, which was introduced in accordance with the European Antimicrobial Resistance Surveillance System (EARSS). Participation in EARSS began in Ireland in 1999. Initially, 12 laboratories serving a mix of general and tertiary hospitals participated, but by 2003, participation had increased to 28 laboratories with a population coverage of 89%. During 1999-2003, 4,146 episodes of Staphylococcus aureus bacteraemia were reported, and methicillin resistance was detected in 1,709 (41.2%) of these isolates. Over the same period, 1,245 invasive (blood or cerebrospinal fluid) episodes of Streptococcus pneumoniae infection were reported, and 160 (12.9%) isolates were found to be non-susceptible to penicillin, with 23 (1.8%) demonstrating high-level penicillin resistance. By 2003, most Irish hospitals were participating in EARSS, which has been a catalyst for the development of a national antimicrobial resistance surveillance programme.


Subject(s)
Drug Resistance, Bacterial , Population Surveillance/methods , Staphylococcus aureus/drug effects , Streptococcus pneumoniae/drug effects , Drug Resistance, Multiple, Bacterial , Humans , Ireland/epidemiology , Logistic Models , Pneumococcal Infections/epidemiology , Pneumococcal Infections/microbiology , Staphylococcal Infections/epidemiology , Staphylococcal Infections/microbiology , Time Factors
20.
Euro Surveill ; 10(5): 9-10, 2005 May.
Article in English | MEDLINE | ID: mdl-29183558

ABSTRACT

Concerns about healthcare-associated infections and the global crisis in antimicrobial resistance has combined to accentuate the fears around so-called "superbugs". In Ireland there is no single agreed indicator regarded as a true measure of the level of methicillin resistant Staphylococcus aureus (MRSA) in hospitals. The objective of this study was to compare two crude measures of MRSA - the percentage of bacteraemia caused by MRSA and the incidence rate (per 1000 bed days used) of MRSA bacteraemia in six acute hospitals. We examined all blood cultures positive for S. aureus (methicillin sensitive and resistant) from 2002 to 2004 in the Health Service Executive (HSE) Mid-Western Area of Ireland. Hospital In-Patient Enquiry (HIPE) data was used to determine monthly in-patient bed days used. Of 245 patient episodes of bacteraemia, 119 were MRSA. The trends in the percentage of isolates that were MRSA and the incidence rate calculated were compared. The incidence rate appears to be a more reliable and robust indicator of MRSA in hospitals than the percentage. Despite many difficulties in interpreting indicators of MRSA they should not preclude the regular publication of data at least at regional level in Ireland.

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