Swift evaluation of electron density profiles obtained by the alkali beam emission spectroscopy technique using linearized reconstruction.

A method is presented for the swift reconstruction of electron density profiles measured by the alkali beam emission spectroscopy. It is based on the linearization of the governing rate equations and leads to a direct calculation for obtaining the profiles. The uncertainties of the measurement are incorporated into the problem through the utilization of Tikhonov regularization and the generalized least squares method. An approximation for the uncertainty of the reconstructed density data is calculated as well. The applicability of the method is tested against both simulated and real experimental results of the W7-X stellarator.

Geographic access to buprenorphine prescribers for patients who use public transit.

OBJECTIVE: Urban Medicaid enrollees with opioid use disorder often rely on public transit to reach buprenorphine prescribers. Research has not shown whether public transit provides this population with adequate geographic access to buprenorphine prescribers. We examined travel times to buprenorphine prescribers by car and public transit in urban areas, and determined whether car-based Medicaid regulatory standards produce their intended geographic coverage. METHODS: We obtained data for this study from the Substance Abuse and Mental Health Services Administration's Buprenorphine Practitioner Locator, Microsoft Bing Maps, and the American Community Survey. We examined four urban counties at the centers of the metropolitan statistical areas with the highest 2017 accidental drug poisoning death rates: Kanawha, WV; Montgomery, OH; Philadelphia, PA; and St. Louis City, MO. These counties comprised 696 census tracts representing 1,038,564 households. We calculated travel times from each census tract center to the nearest buprenorphine prescribers by car and public transit, and compared that to 30-min regulatory standards and by whether census tracts had below median levels of car access. We calculated Global Moran's I statistics to determine whether spatial clustering was present among census tracts with limited access to buprenorphine prescribers. RESULTS: Households in all but two census tracts could access a buprenorphine prescriber within 30 min by car. However, households in 12.1% (84) of census tracts could not do so by public transit. The correlation between car- and public transit-based travel times to the nearest buprenorphine prescriber was 0.11 (95% CI = 0.07-0.22). More than 15% (47,918) of households in the two less densely populated counties could not travel to the nearest prescriber in 30 min and resided in census tracts where access to cars was relatively low. There was no evidence of spatial clustering among census tracts with public transit travel times exceeding 30 min, or among census tracts with public transit travel times exceeding 30 min and below median values of access to cars. CONCLUSIONS: Geographic access to buprenorphine prescribers is overestimated by regulatory standards that apply car-based travel time estimates, which are a weak proxy for public transit-based travel times. Since geographic areas with limited access to buprenorphine prescribers do not tend to cluster near one another, individually targeted interventions may be necessary to improve buprenorphine access and utilization.

Micro-Faraday cup matrix detector for ion beam measurements in fusion plasmas.

Atomic beam probe is an extension of the routinely used beam emission spectroscopy diagnostic for the plasma edge current fluctuation measurement at magnetically confined plasmas. Beam atoms ionized by the plasma are directed to a curved trajectory by the magnetic field and may be detected close to the wall of the device. The arrival location and current distribution of the ions carry information about the plasma current distribution, the density profile, and the electric potential in the plasma edge. This paper describes a micro-Faraday cup matrix detector for the measurement of the few microampere ion current distribution close to the plasma edge. The device implements a shallow Faraday cup matrix, produced by printed-circuit board technology. Secondary electrons induced by the plasma radiation and the ion bombardment are basically confined into the cups by the tokamak magnetic field. Additionally, a double mask is installed in the front face to limit the ion influx into the cups and supplement secondary electron suppression. The setup was tested in detail using a lithium ion beam in the laboratory. Switching time, cross talk, and fluctuation sensitivity test results in the lab setup are presented along with the detector setup to be installed at the COMPASS tokamak.

Advanced neutral alkali beam diagnostics for applications in fusion research (invited).

Diagnosing the density profile at the edge of high temperature fusion plasmas by an accelerated lithium beam is a known technique since decades. By knowledge of the relevant atomic physics rate coefficients, the plasma electron density profile can be calculated from the relatively calibrated light profile along the beam. Several additional possibilities have already been demonstrated: Charge Exchange Resonance Spectroscopy (CXRS) for ion temperature/flow and Zeeman polarimetry for edge plasma current; therefore the Li-beam diagnostic offers a wealth of information at the plasma edge. The weaknesses of the method are the relatively faint light signal, background light, and technical difficulties of the beam injector which usually seriously limit the applicability. In this talk, we present systematic developments in alkali-beam diagnostics (Li, Na) for the injector and the observation system and detectors which resulted in strongly increased capabilities. Advanced systems have been built, and microsecond scale density profile, turbulence, and zonal flow measurement have been demonstrated. A novel edge current measurement technique has also been designed, and components have been tested with potential microsecond-scale time resolution. Additional possibilities of these advanced systems for spectral measurements (CXRS and various Zeeman schemes) are also discussed.

Nonequilibrium Quantum Criticality and Non-Markovian Environment: Critical Exponent of a Quantum Phase Transition.

We show that the critical exponent of a quantum phase transition in a damped-driven open system is determined by the spectral density function of the reservoir. We consider the open-system variant of the Dicke model, where the driven boson mode and also the large N spin couple to independent reservoirs at zero temperature. The critical exponent, which is 1 if there is no spin-bath coupling, decreases below 1 when the spin couples to a sub-Ohmic reservoir.

Effect of PACAP treatment on kidney morphology and cytokine expression in rat diabetic nephropathy.

Pituitary adenylate cyclase activating polypeptide (PACAP) is a neuropeptide, exerting diverse effects. One of its frequently examined functions is cell protection, which is achieved mainly via inhibiting apoptotic, inflammatory and oxidative processes. All its three receptors (PAC1, VPAC1, VPAC2) are expressed in the kidney and PACAP has been shown to have protective effects against different renal pathologies. Diabetic nephropathy is the leading cause of end stage renal disease. The aim of the present study was to investigate the possible ameliorative effect of PACAP in streptozotocin-induced diabetic nephropathy and to evaluate its anti-inflammatory effect in this model. Diabetes was induced by a single intravenous injection of streptozotocin (65 mg/kg) in male Wistar rats. PACAP-treated animals were administered ip. 20 µg PACAP every second day, while untreated animals were given vehicle. Kidneys were removed after 8-weeks survival. Besides the complex histological analysis (glomerular PAS positive area/glomerulus area, tubular damage, arteriolar hyalinosis), expression of several cytokines was evaluated by cytokine array and Luminex assay. Histological analysis revealed severe diabetic changes in kidneys of control diabetic animals (glomerular PAS-positive area expansion, tubular damage, Armanni-Ebstein phenomenon). PACAP treatment significantly diminished the damage. Diabetic kidneys showed significant cytokine activation compared to their healthy controls. PACAP was effective in downregulation of several cytokines including CINC-1, TIMP-1, LIX, MIG, s-ICAM. To conclude, PACAP is effective in ameliorating diabetic nephropathy at least partly through its well-known anti-inflammatory effect. These results raise the opportunity for the use of PACAP as a possible therapeutic or preventive method in treating the complications of diabetes.

Plasma radiation dynamics with the upgraded Absolute Extreme Ultraviolet tomographical system in the Tokamak à Configuration Variable.

We introduce an upgraded version of a tomographical system which is built up from Absolute Extreme Ultraviolet-type (AXUV) detectors and has been installed on the Tokamak à Configuration Variable (TCV). The system is suitable for the investigation of fast radiative processes usually observed in magnetically confined high-temperature plasmas. The upgrade consists in the detector protection by movable shutters, some modifications to correct original design errors and the improvement in the data evaluation techniques. The short-term sensitivity degradation of the detectors, which is caused by the plasma radiation itself, has been monitored and found to be severe. The results provided by the system are consistent with the measurements obtained with the usual plasma radiation diagnostics installed on TCV. Additionally, the coupling between core plasma radiation and plasma-wall interaction is revealed. This was impossible with other available diagnostics on TCV.

Fundamental interstrain differences in cortical activity between Wistar and Sprague-Dawley rats during global ischemia.

Four-vessel occlusion (4VO), a frequently used model of global cerebral ischemia in rats, results in a dysfunction in wide brain areas, including the cerebral cortex and hippocampus. However, there are pronounced differences in response to global ischemia between the laboratory rat strains used in these studies. In the present work, the immediate acute effects of 4VO-induced global ischemia on the spontaneous electrocorticogram (ECoG) signals were analyzed in Wistar and Sprague-Dawley rats. The ECoG was isoelectric during the 10 min of global cerebral ischemia in Wistar rats and the first burst (FB) was seen 10-13 min after the start of reperfusion. In Sprague-Dawley rats, the FB was detected immediately after the start of 4VO or a few seconds later. The burst suppression ratio (BSR) in Wistar rats decreased to 45% in 5 min after FB, and after 25 min it was approximately 40%. In Sprague-Dawley rats, the BSR was 55% immediately after the FB and it decreased steeply to reach 0% by 10 min. There was also a significant difference between the two strains in the frequency composition of the ECoG pattern. The power spectral densities of the two strains differed virtually throughout the post-ischemic state. The histological results (Evans Blue, Cresyl Violet and Fluoro Jade C stainings) supplemented the electrophysiological data: the neuronal damage in the CA1 pyramids in Wistar rats was severe, whereas in the Sprague-Dawley animals it was only partial. These observations clearly demonstrate that the use of different rat strains (e.g. Wistar vs. Sprague-Dawley) can be a source of considerable variability in the results of acute experiments on global ischemia and it is important that the laboratory rats used in such experiments should be carefully chosen.

Analysis of serum cytokine levels in children with chronic cough associated with Toxocara canis infection.

Toxocara infection is associated with an increased prevalence of airway symptoms and may be a possible aetiologic agent of chronic cough. The occurrence of toxocariasis in Hungary is mild and/or sporadic. The purpose of this study was to investigate the levels of serum cytokines (IL-1, IL-2, IL-4, IL-5, IL-6, IL-10, IL-13, IFN-gamma and TNF-alpha) and total IgE, the blood eosinophil count, the results of skin prick and non-specific bronchus provocation tests in Toxocara-seropositive children with chronic cough relative to those in healthy controls. The patients exhibited moderate eosinophilia, significantly elevated levels of serum total IgE, IL-6, IL-10, IL-13 and IFN-gamma, and higher skin reactivity to common allergens, whereas the bronchial hyperreactivity was similar in the two groups. The protective proinflammatory cytokines (IL-6, IFN-gamma and IL-13) in association with the anti-inflammatory cytokine (IL-10) were simultaneously increased in Toxocara-infected children with chronic cough. During infections, the activation and suppression of immune processes occur simultaneously and cytokines of Th1/Th2 and regulatory T cells contribute to the regulation of the immune response evoked by helminth infections (depending on the parasite load, the timing and duration of the infection and the status of the host immune system).

Switching reciprocity on and off in a magneto-optical x-ray scattering experiment using nuclear resonance of α-(57)Fe foils.

Reciprocity is when the scattering amplitude of wave propagation satisfies a symmetry property, connecting a scattering process with an appropriate reversed one. We report on an experiment using nuclear resonance scattering of synchrotron radiation, which demonstrates that magneto-optical materials do not necessarily violate reciprocity. The setting enables us to switch easily between reciprocity and its violation. In the latter case, the exhibited reciprocity violation is orders of magnitude larger than achieved by previous wave scattering experiments.

Powerful technique to test selectivity of agents acting on cardiac ion channels: the action potential voltage-clamp.

Action potential voltage-clamp (APVC) is a technique to visualize the profile of various currents during the cardiac action potential. This review summarizes potential applications and limitations of APVC, the properties of the most important ion currents in nodal, atrial, and ventricular cardiomyocytes. Accordingly, the profiles ("fingerprints") of the major ion currents in canine ventricular myocytes, i.e. in cells of a species having action potential morphology and set of underlying ion currents very similar to those found in the human heart, are discussed in details. The degree of selectivity of various compounds, which is known to be a critical property of drugs used in APVC experiments, is overviewed. Thus the specificity of agents known to block sodium (tetrodotoxin, saxitoxin), potassium (chromanol 293B, HMR 1556, E-4031, dofetilide, sotalol, 4-aminopyridine, BaCl(2)), calcium (nifedipine, nisolpidine, nicardipine, diltiazem, verapamil, gallopamil), and chloride (anthracene-9-carboxylic acid, DIDS) channels, the inhibitor of the sodium-calcium exchanger (SEA0400), and the activator of sodium current (veratridine) are accordingly discussed. Based on a theory explaining how calcium current inhibitors block calcium channels, the structural comparison of the studied substances usually confirmed the results of the literature. Using these predictions, a hypothetical super-selective calcium channel inhibitor structure was designed. APVC is a valuable tool not only for studying the selectivity of the known ion channel blockers, but is also suitable for safety studies to exclude cardiac ion channel actions of any agent under development.

Dicke-model phase transition in the quantum motion of a Bose-Einstein condensate in an optical cavity.

We show that the motion of a laser-driven Bose-Einstein condensate in a high-finesse optical cavity realizes the spin-boson Dicke model. The quantum phase transition of the Dicke model from the normal to the superradiant phase corresponds to the self-organization of atoms from the homogeneous into a periodically patterned distribution above a critical driving strength. The fragility of the ground state due to photon measurement induced backaction is calculated.

Electron proportional gas counter for linear and elliptical Mössbauer polarimetry.

Design, characterization, and selected applications of a novel electron detector dedicated to conventional perpendicular- and low-angle-incidence conversion electron Mössbauer spectroscopy are presented. The setup is suitable for varying the incident angle and external magnetic fields on Mössbauer source and absorber. Test experiments were performed on alpha-(57)Fe films using a conventional single-line (57)Co(Rh) and magnetically split, (57)Co(alpha-Fe) Mössbauer sources. The integral "blackness effect" in conversion-electron Mössbauer spectra of (57)Fe isotope-enriched absorbers is demonstrated and shown to be pronounced at shallow angles of incidence. In order to determine the alignment and sign of the hyperfine field in an isotope-enriched absorber, the blackness effect is accounted for in a semiempirical way by using single-line source/absorber experimental relative intensities determined independently. This method works with high accuracy for linear polarimetry; however it is only a rough approximation in the case of nearly circular polarimetry.

Excess noise depletion of a Bose-Einstein condensate in an optical cavity.

Quantum fluctuations of a cavity field coupled into the motion of ultracold bosons can be strongly amplified by a mechanism analogous to the Petermann excess noise factor in lasers with unstable cavities. For a Bose-Einstein condensate in a stable optical resonator, the excess noise effect amounts to a significant depletion on long time scales.

Prevalence of adult-type hypolactasia as diagnosed with genetic and lactose hydrogen breath tests in Hungarians.

The prevalence of adult-type hypolactasia varies ethnically and geographically among populations. A C/T(-13910) single nucleotide polymorphism (SNP), upstream of the lactase gene, is known to be associated with lactase non-persistence. The aim of this study was to determine the prevalence of lactase-persistent and non-persistent genotypes in the Hungarian population, the age at onset and the applicability of the lactose H2 breath test in comparison with genetic screening. The prevalence of the C/C(-13910) genotype among adults was 37%. Hypolactasia starts to appear at around 5 years of age. Over the age of 12 years, almost all of those with a C/C(-13910) genotype have lactase non-persistence. The C/C(-13910) genotype was closely associated with a positive lactose H2 breath test in symptomatic children, whereas the lactase-persistent genotypes correlated better with a negative H2 test in a control group. In conclusion, supplementary non-invasive breath and genotyping tests furnish a perfect clinical diagnosis.

Toxocariasis associated with chronic cough in childhood: a longitudinal study in Hungary.

Chronic cough lasting 8 weeks or more often seems to be an intractable problem in childhood. Toxocara infection is associated with an increased prevalence of airway symptoms and may be the possible aetiological agent of chronic cough. Of 425 children aged 2-17 years with chronic cough who were investigated for toxocariasis and the distribution of bronchial asthma (BA), cough variant asthma (CVA) and non-asthmatic eosinophilic bronchitis (NAEB), 136 (32%) were seropositive for Toxocara canis antigens. Ninety-three of the 136 were adequately assessed, diagnosed and followed up during 1 year. BA was diagnosed in 40%, CVA in 27% and NAEB in 33% of the children. The eosinophil cell count, serum T. canis IgG levels and symptoms are predictors of the improvement or the decline of the condition. Presuming the aetiopathogenetic role of T. canis in the inflammatory process of chronic cough, we treated the children not only with inhaled corticosteroid (ICS), but also with a 1-week course of anthelminthics. We could significantly decrease the dose of ICS in 23 (62%) of the 37 with BA. The administration of anthelminthics and the avoidance of sensitizers were sufficient for those with NAEB; none needed ICS. ICS therapy could be stopped 2-3 months later in 17 (68%) of the 25 with CVA. We found that 8 of the 25 with CVA (32%) presented asthmatic symptoms at the end of the 1-year period. In Hungary, T. canis may be a potential sensitizer for chronic cough in seropositive children. Deworming therapy will then alleviate the airway symptoms without exacerbation in patients with BA, and have a positive effect on those with NAEB and the majority of those with CVA.

Cone and cone-rod dystrophy segregating in the same pedigree due to the same novel CRX gene mutation.

AIM: To describe the detailed phenotypes of a multi-generation family affected by autosomal dominant cone-rod dystrophy (adCRD) and characterised by marked intrafamilial heterogeneity, due to a novel frameshift mutation in the CRX gene. METHODS: Six affected and two unaffected family members underwent detailed ophthalmological examination as well as psychophysical and electrophysiological testing. Mutation screening of the CRX gene and segregation analysis were performed in 14 family members from three generations. RESULTS: Clinical examination of six available mutation carriers showed marked phenotypic heterogeneity, presenting with a reduced cone electroretinogram (ERG) and normal rod ERG in one family branch and a negative ERG in the other as the most striking feature. Genetic screening identified a novel mutation in the CRX gene, c.636delC, that independently segregates with the disease in both branches of the family. CONCLUSION: The authors identified a novel disease causing mutation in the CRX gene associated with adCRD. Furthermore, we show here for the first time the coexistence of a reduced cone and a negative ERG component in different individuals of the same family, all affected by the same mutation.

Effects of magnesium supplementation on the glutathione redox system in atopic asthmatic children.

OBJECTIVE: Our aim was to investigate the effects of 12-week oral magnesium (Mg) supplementation on the RBC redox system in stable, persistent, moderately asthmatic children (N = 40, 24 boys, 16 girls) aged 4-16 years in a randomized, double-blind, placebo-controlled study. DESIGN: Oxidized (GSSG) and reduced (GSH) glutathione, oxyhaemoglobin, methaemoglobin (metHb), hemichrome and bilirubin levels before and after treatment were determined, and GSH stability tests were performed. RESULT: The GSH concentration was significantly higher in the Mg-treated than in the placebo-treated patients after the treatment period. There was a positive correlation between the decreased plasma metHb and hemichrome levels and the decreased plasma haemoglobin concentrations in the Mg-treated patients at the end of the study. CONCLUSION: Mg in the given doses exerts antioxidant activity and influences the glutathione redox system.

Speech activation SPECT and plasticity of language networks.

Neuronal activity might be measured by regional cerebral blood flow (rCBF) Single Photon Emission Computed Tomography (SPECT) as there is a close relationship between neuronal activity and rCBF changes. In order to study the hemispheric dominance for language and the plasticity of language networks by measuring the rCBF rest and language activation SPECT studies were performed in the presurgical evaluation of ten right-handed and two left handed patients with brain lesions of the dominant hemisphere. A special group of hemisphere-specific neuropsychologic tasks were used for activation, after a proper psychologic conditioning. The rCBF results were calculated by comparing the rest and activation SPECT data using a special regions of interest program and asymmetry index (AI). We compared the results of speech-activation to the results of clinical, morphological (MRI), and postoperative data. In controls, significant activation was found in Brodmann's area 44 and 45, contralateral cerebellum, superior middle and posterior temporal gyrus. In patients, additional regions of activation were seen in contralateral frontal and temporal regions, and in ipsilateral temporal region. AIs of the cerebellum demonstrated a negative correlation with hemispheric dominance for language. In conclusion, significant changes in rCBF in or adjacent to the eloquent areas with various patterns of rCBF changes of the additional regions demonstrate the close relationship between neuronal activity and cerebral blood flow, that can be measured by SPECT.

Coarsening of antiferromagnetic domains in multilayers: the key role of magnetocrystalline anisotropy.

The domain structure of an antiferromagnetic superlattice is studied. Synchrotron Mössbauer and polarized neutron reflectometric maps show micrometer-size primary domain formation as the external field decreases from saturation to remanence. A secondary domain state consisting mainly of at least 1 order of magnitude larger domains is created when a small field along the layer magnetizations induces a bulk-spin-flop transition. The domain-size distribution is reproducibly dependent on the magnetic prehistory. The condition for domain coarsening is shown to be the equilibrium of the external field energy with the anisotropy energy.