Evidence of Electron Heating by Alpha Particles in JET Deuterium-Tritium Plasmas.

The fusion-born alpha particle heating in magnetically confined fusion machines is a high priority subject for studies. The self-heating of thermonuclear fusion plasma by alpha particles was observed in recent deuterium-tritium (D-T) experiments on the joint European torus. This observation was possible by conducting so-called "afterglow" experiments where transient high fusion yield was achieved with neutral beam injection as the only external heating source, and then termination of the heating at peak performance. This allowed the first direct evidence for electron heating of plasmas by fusion-born alphas to be obtained. Interpretive transport modeling of the relevant D-T and reference deuterium discharges is consistent with the alpha particle heating observation.

A high-resolution neutron spectroscopic camera for the SPARC tokamak based on the Jet European Torus deuterium-tritium experience.

Dedicated nuclear diagnostics have been designed, developed, and built within EUROFUSION enhancement programs in the last ten years for installation at the Joint European Torus and capable of operation in high power Deuterium-Tritium (DT) plasmas. The recent DT Experiment campaign, called DTE2, has been successfully carried out in the second half of 2021 and provides a unique opportunity to evaluate the performance of the new nuclear diagnostics and for an understanding of their behavior in the record high 14 MeV neutron yields (up to 4.7 × 1018 n/s) and total number of neutrons (up to 2 × 1019 n) achieved on a tokamak. In this work, we will focus on the 14 MeV high resolution neutron spectrometers based on artificial diamonds which, for the first time, have extensively been used to measure 14 MeV DT neutron spectra with unprecedented energy resolution (Full Width at Half Maximum of ≈1% at 14 MeV). The work will describe their long-term stability and operation over the DTE2 campaign as well as their performance as neutron spectrometers in terms of achieved energy resolution and high rate capability. This important experience will be used to outline the concept of a spectroscopic neutron camera for the SPARC tokamak. The proposed neutron camera will be the first one to feature the dual capability to measure (i) the 2.5 and 14 MeV neutron emissivity profile via the conventional neutron detectors based on liquid or plastics scintillators and (ii) the 14 MeV neutron spectral emission via the use of high-resolution diamond-based spectrometers. The new opportunities opened by the spectroscopic neutron camera to measure plasma parameters will be discussed.

Role of neutron attenuators for gamma-ray measurements in deuterium-tritium magnetic confinement plasmas.

The Joint European Torus (JET) is the only tokamak in the world able to operate in Deuterium-Tritium (DT) plasmas. A successful DT experimental campaign, the DTE2, has recently been carried out, providing unique opportunities for studying both physics and technological aspects. In particular, it allowed us to investigate and benchmark the solutions adopted to attenuate the significant 14 MeV neutron flux, needed to enable high-resolution gamma-ray spectroscopy measurements on a tokamak. While in inertial confinement experiments, gamma-rays and neutrons are discriminated through time-of-flight techniques; in magnetic confinement experiments, the neutron attenuators are a key element to allow gamma-ray measurements in order to reestablish the 1 × 105 to 1 background to signal ratio. In this paper, the role of the reference neutron attenuators at JET, based on LiH, has been analyzed and described.

Fusion product measurements by nuclear diagnostics in the Joint European Torus deuterium-tritium 2 campaign (invited).

A new deuterium-tritium experimental, DTE2, campaign has been conducted at the Joint European Torus (JET) between August 2021 and late December 2021. Motivated by significant enhancements in the past decade at JET, such as the ITER-like wall and enhanced auxiliary heating power, the campaign achieved a new fusion energy world record and performed a broad range of fundamental experiments to inform ITER physics scenarios and operations. New capabilities in the area of fusion product measurements by nuclear diagnostics were available as a result of a decade long enhancement program. These have been tested for the first time in DTE2 and a concise overview is provided here. Confined alpha particle measurements by gamma-ray spectroscopy were successfully demonstrated, albeit with limitations at neutron rates higher than some 1017 n/s. High resolution neutron spectroscopy measurements with the magnetic proton recoil instrument were complemented by novel data from a set of synthetic diamond detectors, which enabled studies of the supra-thermal contributions to the neutron emission. In the area of escaping fast ion diagnostics, a lost fast ion detector and a set of Faraday cups made it possible to determine information on the velocity space and poloidal distribution of the lost alpha particles for the first time. This extensive set of data provides unique information for fundamental physics studies and validation of the numerical models, which are key to inform the physics and scenarios of ITER.

Vesicourachal diverticulum.

We report a rare complication involving a healthy 45-year-old male patient who underwent an emergency laparoscopic appendicectomy for acute perforated gangrenous appendicitis. The patient was catheterised pre- procedure and the ports were inserted under vision. Upon completion of the procedure, a 15 Fr Robinson drain was left in the pelvis and was fed through the suprapubic port hole. Postoperatively the patient developed worsening, generalised abdominal pain and high output from the drain. The patient was re-catheterised but the computed tomography (CT) cystogram did not show any injury to the bladder. The drain fluid creatinine was noted to be raised (>4,000), indicating that urine was leaking into the drain. Conventional cystogram confirmed a contrast leak from the dome around the drain. Flexible cystoscopy confirmed that the drain had transversed the vesicourachal diverticula. The drain was pulled back and converted to a suprapubic catheter with the patient subsequently being discharged. Vesicourachal diverticula is a rare and often asymptomatic anomaly. When undertaking laparoscopic surgery, precautions should be taken to prevent port site injury such as catheterising the patient to ensure the bladder is empty and inserting the ports under direct vision. It is safer to visualise muscle rather than peritoneum during port insertion. In this case, the bladder diverticula was noticed extraperitoneally. Though the indirect CT cystogram reported no injury, this was unreliable as the bladder was not distended which led to the subtle injury being missed. Traditional cystogram should be considered in cases with a negative CT cystogram and a strong suspicion of bladder injury.

First tomographic image of neutron capture rate in a BNCT facility.

This work discusses the development of online dosimetry of the boron dose via Single Photon Emission Computed Tomography (SPECT) during a BNCT treatment irradiation. Such a system will allow the online computation of boron dose maps without the large current uncertainties in the assessment of the boron concentration in different tissues. The first tomographic boron dose image with a SPECT prototype is shown.

A cancer research UK pharmacokinetic study of BPA-mannitol in patients with high grade glioma to optimise uptake parameters for clinical trials of BNCT.

This paper describes results to-date from a human pharmacokinetic study which began recruitment in December 2007. Results are presented for a single patient recruited in December 2007. A second patient was recruited in July 2008 but detailed data are not available at the time of writing. The trial is an open-label, non-comparative, non-therapeutic study of BPA-mannitol in patients with high-grade glioma, who will be undergoing stereotactic brain biopsy as part of the diagnostic process before definitive treatment. The study investigates the route of infusion (intra-venous (IV) or intra-carotid artery) and in each case will assess the effect of administration of mannitol as a blood-brain barrier disrupter. All cohorts will receive a 2 h infusion of BPA-mannitol, and for some cohorts an additional mannitol bolus will be administered at the beginning of this infusion. Measurements are made by inductively coupled plasma mass spectrometry (ICP-MS) of (10)B concentration in samples of blood, urine, extra-cellular fluid in normal brain (via a dialysis probe), brain tissue around tumour and tumour tissue. Additional analysis of the tumour tissue is performed using secondary ion mass spectrometry (SIMS). The first patient was part of the cohort having intra-venous infusion without mannitol bolus. No serious clinical problems were experienced and the assay results can be compared with available patient data from other BNCT centres. In particular we note that the peak (10)B concentration in blood was 28.1 mg/ml for a total BPA administration of 350 mg/kg which is very consistent with the previous experience with BPA-fructose reported by the Helsinki group.

Experimental feasibility studies on a SPECT tomograph for BNCT dosimetry.

This article reports on the development of a prototype of a SPECT tomograph system for online dosimetry in BNCT based on LaBr(3)(Ce) scintillation detectors. The setup shielding was optimized to be used in the accelerator based BNCT facility of the University of Birmingham. The system was designed and built. An image of a (241)Am point source was reconstructed. A projection of a phantom with two tumors with 400 microg/g of (10)B was measured at the BNCT facility.

Effect of remineralization/demineralization cycles on mineral profiles of Fuji IX Fast in vitro using electron probe microanalysis.

BACKGROUND: There have been cononcerns about the dissolution of conventional glass ionomer cement (GIC) and its possible degradation when exposed to an acidic environment over time. The objective of this study was to investigate the effects of exposure of Fuji IX Fast to the simulated acidic aspects of the oral environment in terms of any change in the elemental composition of strontium (Sr), phosphorus (P), calcium (Ca) and fluorine (F) which resulted at the surface of this material. METHODS: Sixty-five cylindrical block of Fuji IX Fast were prepared using split moulds. The demineralizing solution was an acetate buffered demineralizing solution at pH 403. The remineralizing solution was a buffered solution containing 1.5 mM Ca, 0.9 mM P and 10 ppm F at pH 7. The blocks of Fuji IX Fast were subjected either to two-day alternating cycles of remineralization and demineralization for up to 24 days (test); 6 two-day cycles of demineralizing or remineralizing solution separately, or deionized distilled water alone (controls) or were left untreated (base line control). Mineral profiles of Ca, P, Sr and F within 100 microm of the material surface were assessed following 8, 16 and 24 days of treatment (test); 4, 8 or 12 days (controls) or for baseline control samples, using electron probe microanalysis (EPMA). RESULTS: There were significant changes in mineral profile in the test specimens in terms of Sr and Ca concentrations. A molecule for molecule exchange of these elements resulted between GIC and eluant solutions. Fluoride loss from the GIC occurredto the level comparable with uptake levels recorded in eluant solutions from previous studies. The ionic exchanges appeared to be the result of dissolution followed by an equilibrium-driven diffusion. These exchanges were superficial though substantial. CONCLUSIONS: Simulated exposure of Fuji IX to the oral environment resulted in an exchange of Ca from the bathing solutions into Fuji IX to replace any Sr which was lost to the GIC. Fluorine loss from the GIC followed previously described patterns. The possible clinical significance of this exchange was discussed.

Antinociceptive, anti-inflammatory and antipyretic properties of Melastoma malabathricum leaves aqueous extract in experimental animals.

The present study was carried out to establish the antinociceptive, anti-inflammatory, and antipyretic properties of the aqueous extract of Melastoma malabathricum leaves in experimental animals. The antinociceptive activity was measured using abdominal constriction, hot-plate, and formalin tests, whereas the anti-inflammatory and antipyretic activities were measured using carrageenan-induced paw edema and brewer's yeast-induced pyrexia tests, respectively. The extract, which was obtained after soaking the air-dried leaves in distilled water for 72 h and then preparing in concentrations of 10%, 50%, and 100% (v/v), was administered subcutaneously 30 min prior to subjection to the above mentioned assays. At all concentrations tested, the extract was found to exhibit significant (P < 0.05) antinociceptive, anti-inflammatory, and antipyretic activities in a concentration-independent manner. Our findings that the aqueous extract of M. malabathricum possesses antinociceptive, anti-inflammatory, and antipyretic activities supports previous claims on its traditional uses to treat various ailments.

First report of Escherichia coli O157 among Iraqi children.

We determined the prevalence of enterohaemorrhagic Escherichia coli, especially E. coli O157, and other enteropathogens among 200 children with bloody diarrhoea and 100 age-matched controls at two Baghdad hospitals. Bacterial and parasitic agents were found in 39.5% and 28.5% of cases, respectively; no pathogen was detected in 32%. E. coli O157 was identified in 11.5% and more than one pathogen was found in 15.5% of cases. The most common pathogens were enteropathogenic E. coli (EPEC) (5%); E. coli other than E. coli O157 or EPEC (15%); Entamoeba histolytica (25%) and Giardia lamblia (3.5%). All isolates of E. coli O157:H7 were sensitive to cephalexin, ciprofloxacin, gentamicin and nalidixic acid and resistant to erythromycin, polymyxin B and vancomycin. Resistance to 6 or more antimicrobial agents was common (50% of isolates).

First report of Escherichia coli O157 among Iraqi children

We determined the prevalence of enterohaemorrhagic Escherichia coli, especially E. coli O157, and other enteropathogens among 200 children with bloody diarrhoea and 100 age-matched controls at two Baghdad hospitals. Bacterial and parasitic agents were found in 39.5% and 28.5% of cases, respectively; no pathogen was detected in 32%. E. coli O157 was identified in 11.5% and more than one pathogen was found in 15.5% of cases. The most common pathogens were enteropathogenic E. coli [EPEC] [5%]; E. coli other than E. coli O157 or EPEC [15%]; Entamoeba histolytica [25%] and Giardia lamblia [3.5%]. All isolates of E. coli O157:H7 were sensitive to cephalexin, ciprofloxacin, gentamicin and nalidixic acid and resistant to erythromycin, polymyxin B and vancomycin. Resistance to 6 or more antimicrobial agents was common [50% of isolates]