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.

Upgrade and absolute calibration of the JET scintillator-based fast-ion loss detector.

The JET FILD is a scintillator-based Fast-ion Loss Detector optimized to measure fusion-born alpha-particle losses. This work covers its upgrade and absolute calibration in preparation for the following JET DT experiments. A fast scintillator material (TG-Green) has been installed in the JET FILD. A heater jacket is installed around the fiber bundle, responsible for transmitting the light from the scintillator plate, to anneal the fiber obscuring due to neutron damage. The JET FILD has been upgraded with a 1 Mpx camera and 2 MHz photomultiplier data acquisition hardware. Full-orbit simulations give an estimate of the shading effects on the scintillator plate of the first wall structures and provide a synthetic signal of the JET FILD. A detector instrument function enables absolute values of fast-ion losses using calibration factors. The calibration factors are made available in a shot-to-shot basis for the characterized species and energies and with corrections for the diagnostic conditions. The fast acquisition system sets the Nyquist frequency (1 MHz) above the typical mode frequencies (≈102 kHz), thus making it possible to identify MHD-induced fast-ion losses.

Improvements to the Faraday cup fast ion loss detector and magnetohydrodynamic induced fast ion loss measurements in Joint European Torus plasmas.

Upgrades to electronic hardware and detector design have been made to the JET thin-foil Faraday cup fast ion loss detector [Darrow et al., Rev. Sci. Instrum. 75, 3566 (2004)] in anticipation of the upcoming deuterium-tritium (DT) campaign. An improved foil stack design has been implemented, which greatly reduces the number of foil-to-foil shorts, and triaxial cabling has mitigated ambient noise pickup. Initial tests of 200 kHz digitizers, as opposed to the original 5 kHz digitizers, have provided enhanced analysis techniques and direct coherence measurements of fast ion losses with magnetohydrodynamic activity. We present recent loss measurements in JET deuterium plasmas correlated with kink modes, fishbone modes, edge-localized modes, and sawteeth. Sources of systematic noise are discussed with emphasis on capacitive plasma pickup. Overall, the system upgrades have established a diagnostic capable of recording alpha particle losses due to a wide variety of resonant fast ion transport mechanisms to be used in future DT-experiments and modeling efforts.

Dated rock engravings from wonderwerk cave, South Africa.

Radiocarbon dates associated with engraved stones from sealed archeological deposits at Wonderwerk Cave in the northern Cape Province indicate that rock engraving in South Africa is at least 10,000 years old.

Role of glutathione S-transferases in the resistance of human colon cancer cell lines to doxorubicin.

The anthracycline doxorubicin has little activity against colorectal cancers. It is hypothesized that this is attributable to a multifactorial resistance mechanism in which the glutathione S-transferases (GST) may play a role. We studied the relationship between GST expression and doxorubicin resistance in four human colon adenocarcinoma cell lines (HT-29, LoVo, SW620, and Caco-2), with the goal of modulating GST activity to overcome resistance. Caco-2 cells were the most resistant to doxorubicin, showing an IC50 value approximately 80- to 90-fold higher than HT-29 or LoVo and 600-fold higher than SW620. Total GST catalytic activity was significantly higher in Caco-2 cells compared with the other lines. All four cell lines expressed GST-pi at the catalytic activity, protein, and mRNA levels; however, no significant differences were observed among the cell lines. GST-mu expression was not detectable at the protein and mRNA levels, and the four cell lines displayed very low catalytic activity toward a GST-mu-selective substrate. Caco-2 cells showed a unique, highly expressed GST-alpha-immunoreactive band that was not detected in the other lines; however, the glutathione peroxidase activity of Caco-2 cells was the lowest among the four cell lines. Neither ethacrynic acid nor glutathione analogues that function as GST class-selective inhibitors were able to potentiate the cytotoxic effects of doxorubicin in these colon cancer cell lines, as demonstrated in both microplate colorimetric and clonogenic assays. The multidrug resistance-associated protein and P-glycoprotein were either not detectable or expressed at such low levels that they are not likely to contribute to the differences in doxorubicin sensitivity observed among these cell lines.

A laser flash photolysis study of the reactivities of the triplet states of 8-methoxypsoralen and 4,5',8-trimethylpsoralen with nucleic acid bases in solution.

The extinction coefficients, quantum yields and reactivities of the triplet states of 8-methoxypsoralen and 4,5',8-trimethylpsoralen in methanolic solution have been determined using laser flash photolysis techniques. The second-order rate constants for the quenching of these triplet states by pyrimidine and purine bases were found to be several orders of magnitude lower than those found for other furocoumarin derivatives. This may suggest, therefore, that the skin photosensitising ability of such compounds does not necessarily correlate with in vitro triplet state reactivity. Preliminary experiments on the reactivity of the psoralen triplet state with DNA itself indicate that no transient absorptions due to psoralen excited states can be observed when a photon is absorbed by the psoralen-DNA complex.

The reactivity of various free radicals with hyaluronic acid: steady-state and pulse radiolysis studies.

The reactions of the primary water radicals with the biopolymer hyaluronic acid have been studied by pulse radiolysis. Bimolecular rate constants, expressed in terms of the disaccharide repeating sub-unit of hyaluronic acid, for OH., H. and eaq- were found to be 7 X 10(8) M-1 X s-1, 5 X 10(7) M-1 X s-1 and less than 5 X 10(6) M-1 X s-1, respectively. By comparing the viscosities of samples, gamma-irradiated in the steady state under a variety of conditions, with unirradiated controls, the efficiencies with which selected radicals cause chain breakage have been determined. Efficiencies of 30%, 15%, 0%, 0.2% and 5% were estimated for OH., H., eaq-, methanol radicals and tert-butanol radicals, respectively. The presence of oxygen during irradiation increased the extent of chain breakage by a factor of 1.75.

A pulse radiolysis study of the complexing of furocoumarins with DNA and proteins.

The complexing of furocoumarins with DNA in aqueous solution has been investigated using the fast-reaction technique of pulse radiolysis. Association constants are given for 8-methoxypsoralen, psoralen, khellin, angelicin, 5,7-dimethoxycoumarin, 5-methoxypsoralen and 4'-aminomethyl-4,5',8-trimethylpsoralen. In addition, the complexing of some furocoumarins to the protein, bovine serum albumin, has also been studied.

The reactivities of furocoumarin excited states with DNA in solution. A laser flash photolysis and fluorescence study.

The effect of DNA on both the fluorescence emission spectra and yields and lifetimes of the triplet stae of psoralen and 8-methoxypsoralen in aqueous solution has been determined. The changes in the fluorescence spectra are similar in nature for both of these furocoumarins and are attributed to binding of the drug to DNA. The yield of the 8-methoxypsoralen triplet state when bound to DNA was found to be similar, if not identical, to that measured in the absence of DNA. This contrasts sharply with data obtained for psoralen from which it is concluded that either the yield of bound psoralen triplet states is very low, if not zero, or that the lifetime of such species is less than 50 ns. The relevance of this data to the molecular basis of skin photosensitisation by furocoumarins is discussed.

Pattern of vascular nonperfusion in retinal venous occlusions occurring within the optic nerve with and without optic nerve head swelling.

OBJECTIVE: To investigate the significance of optic nerve head swelling (ONHS) in relation to the pattern of vascular nonperfusion, visual acuity (VA), and demographic profile in retinal venous occlusions (RVOs) occurring within the optic nerve. METHODS: Cases of RVO occurring within the optic nerve were divided on the basis of the presence (105 cases) or absence (163 cases) of ONHS. This division was performed by examining the color stereo fundus photographs in conditions masked from other clinical parameters. Duration of symptoms before assessment, age, and sex distributions were compared. The vein involved was identified, and the occlusion was confirmed to have occurred within the optic nerve by observing that the vein pierced the lamina cribrosa as a dilated vein. Fluorescein angiographs were examined, and the extent of vascular nonperfusion in the macula and peripheral retina was quantified from grade 1 to grade 4. The extent of break in the perifoveal capillary arcade was graded as 0, less than or equal to 90 degrees, and greater than 90 degrees. Best-corrected VA was assessed using the Snellen chart. RESULTS: The 2 groups were comparable in terms of the duration of the symptoms before examination. The mean age was significantly younger in the group with ONHS (58.3 vs 65.1 years, P<. 001). Age distribution by sex demonstrated a higher proportion of men younger than 50 years in the ONHS group (19.1% vs 8.6%, P =.01). The group without ONHS involved the papillary vein more frequently (31.3% vs 17.1%, P =.01). The respective proportions of grade 1, 2, 3, and 4 vascular nonperfusion in the macula were 90.5%, 9.5%, 0%, and 0% in the ONHS group, and 62.6%, 14.7%, 13.5%, and 9.2% in the group without ONHS (P<.001). The corresponding proportions for the peripheral retina were 90.4%, 8.7%, 0%, and 1.0% in the ONHS group, and 62.7%, 13.0%, 18.0%, and 6.2% in the group without ONHS (P<.001). In 64.6% of cases with ONHS and 42.9% of cases without, the perifoveal arcade was intact. A break greater than 90 degrees in the perifoveal arcade was present in 12.5% of cases with and 23.6% of cases without ONHS (P =.004). The median VA was significantly better in the ONHS group (6/24 vs 6/48, P =.005). CONCLUSIONS: The RVOs occurring within the optic nerve can be subdivided into 2 distinct groups on the basis of ONHS. The presence of ONHS is associated with younger age, less severe vascular nonperfusion, and better VA. This is consistent with a retrocribrosal site of occlusion, which has access to the pial plexus that can provide collateral channels for retinal venous drainage.

Excitatory amino acid receptors in the parallel fibre pathway in rat cerebellar slices.

The grease-gap technique was used on young rat cerebellar slices to study the synaptic pharmacology of the parallel fibre pathway. Electrical stimulation of the parallel fibres produced a characteristic response in Purkinje cells: a sharp negative (N) potential, representing the population action potential and underlying parallel fibre EPSP, followed by a slow positive (P) wave, the population inhibitory postsynaptic potential (IPSP). In the presence of 1.2 mM Mg2+, D-2-amino-5-phosphonovalerate (APV, 30 microM) had no effect but both potentials could be inhibited by 6-cyano-2,3-dihydroxy-7-nitro-quinoxaline (CNQX, 10 microM). Removal of Mg2+ had no effect on the N-potential but enhanced the P-wave in an APV-sensitive fashion, particularly when CNQX was present. The results provide further evidence that glutamate is the parallel fibre transmitter and suggest that its acts only on non-NMDA (non-N-methyl-D-aspartate) receptors at synapses with Purkinje cells but on both NMDA and non-NMDA receptors at synapses with inhibitory interneurones. At the latter synapses, the NMDA system is likely to be brought into operation in an activity-dependent manner.

The effect of mercuric ions on the excited states of DNA-intercalated ethidium bromide.

The first excited triplet state of DNA-intercalated ethidium bromide is produced with a quantum yield of 0.01 +/- 0.002 on irradiation at 532 nm. A difference extinction coefficient of 1.5 +/- 0.2 x 10(3) m2 mol-1 is measured for the triplet state at 380 nm. Mercuric ions quench the first excited singlet state of DNA-intercalated ethidium bromide via induced spin orbit coupling to give an increased yield of ethidium triplet states. The same mercuric ion that quenches the singlet state then quenches the triplet state, via the same mechanism, with a rate constant of ca 3.5 x 10(3) s-1. An upper limit for the rate of detachment of Hg2+ from its binding site in DNA may be fixed at ca 10(3) s-1.

Clinical characteristics of retinal venous occlusions occurring at different sites.

AIMS: To identify the contributory factors associated with different sites of occlusion and the presence or absence of optic nerve head swelling (ONHS). METHODS: 874 cases of retinal venous occlusion (RVO) were prospectively examined at a tertiary referral centre and classified according to three defined sites of occlusion: arteriovenous crossing RVO (AV-RVO); optic cup RVO (OC-RVO); and optic nerve sited RVO. Optic nerve sited RVOs were further divided on the basis of presence (ONHS-RVO) and absence (NONHS-RVO) of ONHS. RVOs not occurring at any of the defined sites were grouped as no-site RVO (NS-RVO). Important clinical parameters were compared among four of the five subgroups by multivariate analysis of variance and chi(2) test (NS-RVO excluded). RESULTS: The overall multivariate analysis of variance for differences in the mean age, systolic and diastolic blood pressure, body mass index, and intraocular pressure (IOP) among the four subgroups were highly significant (p <0.0001). The F ratios indicated that the differences in the mean age and IOP accounted for this statistical trend. The mean age was statistically significantly lower in the ONHS-RVO group compared to the rest of the groups (p <0.0001). The mean age was significantly higher in OC-RVO compared to the AV-RVO group (p <0.05). The mean IOP was significantly higher in OC-RVO than in the rest of the groups (p <0.01 to 0.0001), while it was also higher in the NONHS-RVO group compared to the ONHS-RVO and AV-RVO groups (p <0.0001). The prevalence of primary open angle glaucoma (POAG), sex, laterality, involvement of the fellow eye, smoking and hypertension were compared by chi(2) tests. POAG was significantly more prevalent in the OC-RVO group than in the rest of the groups (p <0.0083), while it was also significantly more prevalent in the NONHS-RVO group compared to AV-RVO or ONHS-RVO (p <0.0083) groups. Smoking was significantly more prevalent in AV-RVO than in the rest of the groups (p <0.05). The proportion of male sex was significantly higher in ONHS-RVO compared to the AV-RVO group (p <0.05). Hypertension was significantly more prevalent in the AV-RVO than in the ONHS-RVO or NONHS-RVO groups (p <0.05). CONCLUSION: A new classification of RVO based on the site of occlusion and ONHS has been evaluated. The higher prevalence of hypertension and smoking in AV-RVO suggests a particular importance of cardiovascular risk factors in this group. The association of POAG with CRVO has been confirmed, but only for those cases without ONHS. A distinctive relation between raised IOP and OC-RVO has been demonstrated, suggesting a causal association. RVOs with ONHS tend to occur in younger people, with a higher proportion of males, and a lower prevalence of hypertension and POAG, suggesting that other causal factors may be important in this group. The new scheme resolves the confusion in the literature regarding classification of RVO, and has diagnostic, causal, prognostic, and therapeutic implications.

Treatment of choroidal neovascularisation in age-related macular degeneration with interferon alfa-2a and alfa-2b.

Forty eight eyes of 42 patients with choroidal neovascular membranes and age-related macular degeneration who received three different dose regimens of systemic interferon alfa-2 were studied retrospectively. The response to treatment of 41 eyes of the 37 patients who received at least 4 weeks' treatment was analysed with respect to the change in size of the choroidal neovascular membrane and the visual acuity compared with pretreatment levels. The size of the membrane at the end of the course of treatment had decreased in seven (17%) eyes overall, not changed in 16 (39%), and increased in 18 (44%). At the end of treatment, the visual acuity had improved in seven (17%) eyes, not changed in 27 (66%), and deteriorated in seven (17%). With an average follow up of 10 months after treatment, the visual acuity had deteriorated compared with the pretreatment value in 21 out of 41 (51%) eyes. Vision improved in some fellow eyes with disciform scars. Side effects were common and often severe. The data suggest that one of the major effects of interferon alfa may be to decrease vascular permeability. While further research may identify a place for interferon alfa in the treatment of choroidal neovascularisation, we were unable to demonstrate that the treatment regimens of systemic interferon alfa we used caused a dramatic benefit to patients with exudative age-related macular degeneration.

Widespread choroidal insufficiency in primary open-angle glaucoma.

PURPOSE: The purpose of this study was to investigate choroidal perfusion in glaucoma, using histological and angiographic techniques. METHODS: We examined the choroidal vasculature in clinicopathological slides from 25 cases of primary open-angle glaucoma, five cases of optic atrophy, and 18 normal eyes. We measured choroidal thickness at fixed distances from the disk margin with light microscopy. Using a quantitative computer image analysis system, we established the depth of all vessels and the best fitting diameter and width-to-length ratio for each vessel in three pairs of eyes. Separate statistical analyses were done on the parapapillary area and the whole choroid. We compared standard fluorescein angiographic measures to peak choroidal filling time in a further 78 glaucoma and 84 normal eyes. RESULTS: Choroids were significantly (approximately 50 microns) thinner in glaucoma than in normal or optic atrophy irrespective of fundal position. Vessel frequency and mean diameter, relative to normal, showed greatest decrease near the choriocapillaris. Peak choroidal filling was the only fluorescein angiographic measure that was significantly delayed in glaucoma irrespective of age. CONCLUSIONS: Reduced choroidal thickness in primary open-angle glaucoma is primarily due to loss of the innermost choroidal vessels. Overall size decreases without significant flattening. These changes are not seen with optic atrophy alone and may be correlated with the delayed choroidal perfusion seen in fluorescein angiography.

The automated Hettinger test in the diagnosis and prevention of repetition strain injuries.

The Hettinger test measures changes in skin temperature following vibration of the hand. The test was evaluated on 67 people from light manufacturing and office jobs, and was found to separate the groups of known repetition injured and known repetition uninjured, with 90% accuracy. The high accuracy of the test in diagnosis suggests that physiological factors are very important in the development of these injuries. The test appears to measure a constitutional factor rather than or in addition to injury symptoms, as it identified healed as well as current injuries. The test score of individuals appears to identify their relative susceptibility to injury. Highly susceptible individuals are injured on jobs that are safe for most people. Such people need far more careful treatment than more robust individuals, and may require susceptibility reduction procedures in addition to job redesign. Attention given to susceptibility identification and reduction may yield substantial benefits in reducing injuries from repetitive work.

[Efficacy and safety of prophylactic preoperative administration of low-dose warfarin in cemented total knee prostheses]. / Efficacité et sécurité de la prophylaxie avec warfarine faible dose débutée en pré-opératoire lors de prothèses totales de genou cimentées.

One hundred and fifty six consecutive cemented total knee arthroplasties (TKA) in 147 patients (39 males, 108 females, mean age: 67) received preoperatively low-dose-warfarin for thromboembolic prophylaxis. Warfarin 10 mg was given the night before surgery and warfarin 5 mg the night of surgery. Thereafter, the dosage was adjusted to maintain a prothrombin time between 1.2-1.5 times control (INR = 2.0-3.0). The screening for any deep vein thrombosis (DVT) in the operated limb was by ascending venography. The reported incidence of DVT after TKA without prophylaxis is superior to 50%, more than 10% of those are proximal DVT. In this study, the overall incidence of DVT is down to 22.4%. Only five patients (3.4%) had a proximal DVT. There were no deaths and no clinical pulmonary embolisms. Patients with venous insufficiency had a significantly higher incidence of DVT (36.7%, p = 0.05). The average blood loss was 406 ml. Three major local bleedings occurred (2.0%). At one year follow-up, there were no infections. Low dose warfarin is efficacious in reducing DVT formation with TKA. It is safe and does not create excessive bleeding in cemented TKA.

[Functional study of Swanson's metacarpophalangeal arthroplasties in rheumatoid arthritis]. / Etude fonctionnelle des arthroplasties métacarpophalangiennes de Swanson dans l'arthrite rhumatoïde.

To validate a functional hand evaluation and to obtain an historical control group in a project of metacarpophalangeal total joint prosthesis, we reviewed our experience over a ten year period of Swanson's metacarpophalangeal joint arthroplasty in rheumatoid arthritis. Forty-nine implants in fourteen rheumatoid arthritis patients were reviewed clinically, radiologically and evaluated by the Arthritic Hand Function Test. The mean follow up was 4.5 years. All patients were ready to repeat the experience except one. The mean metacarpophalangeal joint range of motion was 37 degrees (18 degrees to 55 degrees) with a mean of 7 degrees ulnar deviation. Although their functional performance was 50% of normal, all patients completed the test. The strength was generally greater on the operated side. The low complication rate (6% fracture rate) with the successful functional outcome of Swanson's metacarpophalangeal joint arthroplasty in rheumatoid arthritis will be the gold standard for any new implant to develop.