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A new superconducting magnet test facility was created at the MIT Plasma Science and Fusion Center (PSFC) for the SPARC Toroidal Field Model Coil (TFMC) program. The facility was designed and constructed in parallel with the TFMC between 2019 and 2021, with capabilities and design approaches tailored to the needs of this project and its time line. The major components of the facility include a new cryostat (outer dimensions, 5.3 m × 3.7 m × 1.5 m) with open bore; a novel cooling system circulating supercritical helium in a closed loop to provide $\sim$600 W cooling power at $\sim$20 bar-a, $\sim$20 K; a 50-kA $\pm$ 10-V power supply with supporting nitrogen-cooled high temperature superconductor (HTS) binary current leads operating at record currents, as well as VIPER-cable HTS cold bus; and a new instrumentation and programmable-logic-controller-based control system handling $\sim$650 input and output signals distributed between the facility and the test article. Substantial legacy infrastructure inherited from the PSFC's Alcator C-Mod tokamak program, including liquid nitrogen facilities and 10 mW of ac power, was instrumental in the rapid deployment of these new systems. Immediately after initial commissioning, the facility was used successfully to test the SPARC TFMC, operating the magnet in a campaign achieving 20 T on the coil, as well as a second campaign performing quench testing. The facility has since undergone several upgrades and has been used in campaigns of other test articles, and it is expected that the facility will remain a resource for the community for the foreseeable future to develop fusion magnets and related technology.

In this article, the SPARC Toroidal Field Model Coil (TFMC) experimental tests are described. The tests include detailed comparisons to a hierarchy of electromagnetic and structural models of the coil. The tests confirm the ability of the no-insulation no-twist (NINT) configuration to provide highly stable dc operations with peak magnetic field in excess of 20 T at the rare earth yttrium barium copper oxide (REBCO) tape stacks. The advantages of the modular TFMC approach are validated including the ability to test and probe the REBCO and structural response of the coil in stages, a strategy that will be applied to large-scale coil production for SPARC. The electromagnetic models show high fidelity agreement to the dc and charging coil performance in terms of current distribution, voltages, and heating. The transient response of the TFMC to open-circuit events is examined. The coil exhibits the positive features of the NINT design with very low induced voltages and a predictable redistribution of current and resulting volumetric heating. However, highly localized damage occurs during a programmed open circuit at operational conditions similar to those used in the SPARC tokamak, in agreement with calibrated electromagnetic models. This reveals the cause and remedy to the thermal instability that gives rise to the damage. Therefore, the conclusion of the tests is that the NINT TFMC is confirmed as meeting the programmatic requirements for SPARC and, more generally, for high-field tokamaks.

An overview of the recent operations and the main results of cesium injection in the Source for the Production of Ions of Deuterium Extracted from Rf plasma (SPIDER) negative ion source are described in this contribution. In experiments without cesium injection, all SPIDER plants were tested to verify the basic expectations on the operational parameters (e.g., electron cooling effectiveness of magnetic filter field) and to determine its operational region. For beam properties, it was shown that the current density varies across the beam in the vertical direction. In preliminary cesium experiments, the expected increase of negative ion current and simultaneous decrease of co-extracted electrons were found, along with the influence of the control parameters (polarization of the plasma electrodes, magnetic filter field) on the SPIDER beam uniformity in the horizontal and vertical directions. It was shown that non-Gaussian tails can be identified in the angular distribution on the plane perpendicular to the beam propagation direction. Stray particles, nonhomogeneous beam and large divergence might result in unexpected heat and particle loads over ITER neutral beam injector (NBI) accelerator grids; it is the goal of SPIDER to assess and possibly to identify suitable methods for controlling these beam features. A major shutdown, planned for late 2021, to solve the issues identified during the operation and to carry out scheduled modifications, is outlined. Such improvements are expected to allow SPIDER to pursue the ITER requirements in terms of negative ion current, electron-to-ion ratio, and beam duration.

Le carcinome à cellules de Merkel (CCM) est une tumeur neuroendocrine cutanée primitive maligne rare et agressive, dont la pathogenèse peut être attribuée à l’irradiation par les UV ou à une infection par le polyomavirus de Merkel (MCPyV). Malgré les améliorations de la caractérisation clinique, pathogénique et moléculaire de ces dernières années, de nombreux facteurs pronostiques cruciaux doivent encore être pleinement compris. Récemment, nous avons collecté une série consécutive de 228 CCM diagnostiqués dans trois hôpitaux de Turin. Parmi les différents paramètres pronostiques clinicomorphologiques (statut de MCPyV, taille de la tumeur, ndice de Breslow et lymphocytes infiltrant la tumeur), nous avons observé que l’expression tumorale d’ALK était fortement associée à la présence de MCPyV. De plus, une surexpression d’ALK était associée et à un intervalle sans maladie plus court, représentant ainsi potentiellement un biomarqueur pronostique négatif. Dans la littérature, il est rapporté que ALK est une cible transcriptionnelle directe de MYCN ; en fait, il a été démontré qu’une surexpression d’ALK peut être induite par une amplification de MYCN2. Ces observations nous ont conduits à chercher les causes moléculaires possibles de la surexpression immunohistochimique du ALK en étudiant les altérations moléculaires des deux gènes.

AbstractNowadays, pyrohydrolysis techniques are widely applied for regeneration of spent pickling liquors providing an excellent environmental and economical strategy to the problem of waste disposal/recovery, also thanks to the high acid recovery efficiencies (>99%) achieved. In fact, in these processes, iron chlorides are converted into iron oxides and hydrogen chloride at high temperature in spray roasting or fluidized bed reactors. Though the state-of-the-art technologies have been successfully applied only to large-scale plants, the development of small-scale units, able to perform a delocalized regeneration of spent solutions where these latter are actually produced, would be strongly needed in order to minimize the transportation of hazardous spent pickling and fresh HCl solutions to/from pickling factories from/to large centralized regeneration plants. In the present work, a steady-state simulation model for regeneration of spent pickling liquor via spray roasting has been developed, aiming at the analysis of performance of a small-scale unit. The simulation and optimization of the process has been carried out using Aspen Plus simulator. A simplified model of the spray roaster, based on the data collected from studies reported in the literature, has been implemented and exported from Aspen Custom Modeler. Solid recovery from roaster off-gases has been obtained by a cyclone and a Venturi scrubber, where the spent pickling liquor is concentrated prior to be sprayed into the reactor. Hydrogen chloride is absorbed in an adiabatic absorber, where a sub-azeotropic (18–20 wt%) hydrochloric solution is obtained. Prior to the stack, a scrubber is required to wash off the exhaust gases. Several parametric studies have been performed. Different designs of solid separators have been compared in order to investigate the particulate separation efficiency of the process, while absorption column’s packing types and rinse water flow rates have been varied in order to investigate their effects on HCl recovery and acid gas emissions.

Nowadays, pyrohydrolysis techniques are widely applied for regeneration of spent pickling liquors providing an excellent environmental and economical strategy to the problem of waste disposal/recovery, also thanks to the high acid recovery efficiencies (>99%) achieved. In fact, in these processes, iron chlorides are converted into iron oxides and hydrogen chloride at high temperature in spray roasting or fluidized bed reactors. Though the state-of-the-art technologies have been successfully applied only to large-scale plants, the development of small-scale units, able to perform a delocalized regeneration of spent solutions where these latter are actually produced, would be strongly needed in order to minimize the transportation of hazardous spent pickling and fresh HCl solutions to/from pickling factories from/to large centralized regeneration plants. In the present work, a steady-state simulation model for regeneration of spent pickling liquor via spray roasting has been developed, aiming at the analysis of performance of a small-scale unit. The simulation and optimization of the process has been carried out using Aspen Plus simulator. A simplified model of the spray roaster, based on the data collected from studies reported in the literature, has been implemented and exported from Aspen Custom Modeler. Solid recovery from roaster off-gases has been obtained by a cyclone and a Venturi scrubber, where the spent pickling liquor is concentrated prior to be sprayed into the reactor. Hydrogen chloride is absorbed in an adiabatic absorber, where a sub-azeotropic (18–20 wt%) hydrochloric solution is obtained. Prior to the stack, a scrubber is required to wash off the exhaust gases. Several parametric studies have been performed. Different designs of solid separators have been compared in order to investigate the particulate separation efficiency of the process, while absorption column’s packing types and rinse water flow rates have been varied in order to investigate their effects on HCl recovery and acid gas emissions.

The absorption and emission spectra of dithiophene have been computed in different environments (gas phase, apolar, and polar solvents) and at different temperatures, including Duschinsky, temperature and solvent effects at full ab initio level, and considering the anharmonicity of the double well potential associated with the inter-ring torsional mode. The computed spectra are in very good agreement with the experimental ones, allowing for a complete assignment of the main vibrational features. Five different density functionals (BLYP, B3LYP, CAM-B3LYP, BHLYP, and PBE0) have been tested, and CAM-B3LYP and PBE0 are the most accurate.

Il lichen planus orale (LPO) è considerato una manifestazione extraepatica in corso di malattie croniche del fegato. Al fine di controllare l’incidenza di esacerbazioni cliniche del LPO nelle lesioni atrofico-erosive, si è operato un monitoraggio dei markers sierologici dello stato di funzionalità epatica in pazienti affetti da LPO.

Skeletal demineralization and mineral metabolism derangement are well-recognized features of untreated celiac disease (CD). Although treatment with a gluten-free diet appears to prevent bone loss while correcting skeletal demineralization in childhood, there is evidence that bone mineral density does not return to normal in celiacs diagnosed in adulthood. Osteoprotegerin (OPG), a member of the tumor necrosis factor receptor family, and ligand of receptor activator of NFkB (RANKL) are involved in the process of bone turnover and have been implicated in the pathogenesis of osteoporosis and other metabolic bone diseases. We measured OPG, RANKL, bone mineral density (BMD), and biochemical markers of bone turnover in 32 adult female premenopausal celiac patients on a gluten-free diet, and thirty age-matched healthy women. We correlated the OPG/RANKL ratio with the severity of bone loss. Celiac patients had a mean BMD lower than controls in lumbar spine and in the femoral neck. Serum levels of bone alkaline phosphatase (BAP, marker of bone formation), and urinary excretion of telopeptides of type I collagen (a marker of bone resorption) were significantly higher than in controls. Serum OPG and RANKL levels were significantly higher in CD patients than in controls, while the OPG/RANKL ratio was significantly lower in CD patients than in controls and was positively correlated with BMD at the spine. The role of elevated OPG in CD patients is unclear, but it might represent a compensatory mechanism against other factors that promote bone damage. Further studies are required to assess a possible therapeutic potential of osteoprotegerin in optimally treated celiacs with persistent osteopenia.

We present a semiclassical study of the rovibronic Renner−Teller (RT) effect on the reaction N(²D) + %@mt;sys@%H%@sb@%2%@sbx@%%@fn;(;vis;full;auto@%X%@ex@%1%@exx@%∑%@sx@%g%@be@%+%@sxx@%%@fnx;);vis;full@%%@mx@% → NH2(X²A‘ ‘ + A²A‘) → NH(X³Σ^- + a¹Δ) + H(²S). A new approach for describing RT coupling within the framework of trajectory surface hopping is developed for this application. The calculations include the two lowest-lying electronic states of NH2 as derived from ab initio calculations together with a semiclassical description of the RT coupling. We investigated the role of the RT effect on the integral and differential reactive cross sections for formation of both NH electronic states and on the product distribution by varying the collision energy and the initial rotational state of H2. Our results show that the RT coupling does not affect the reactivity of trajectories starting on the X²A‘ ‘ potential but considerably affects those starting on A²A‘, leading to an almost exclusive formation of NH(X³Σ^-) at collision energies below 5 kcal/mol and a maximum contribution of ~10% to the overall formation of NH(X³Σ^-) for collision energies between 5 and 10 kcal/mol. The dependence of the RT effect on the collision energy and on the rovibrational state of H2 has also been analyzed, and a simple classical interpretation of most of these features based on the time spent by trajectories in the region where the RT coupling is active is proposed. Our results predict that the RT effect is not important to the thermal rate constant but has measurable consequences for certain state-resolved experiments.

The role of the thymus on immunity of rats againstTrypanosoma cruzi infection was investigated in vivo. The athymic (nu/nu) rats were shown to be significantly more susceptible to the acute phase of the infection than the control nu/+ rats, as measured by increased parasitemia and mortality. Specific anti-T. cruzi antibodies, complement, IgM and IgG2a serum levels were determined. The results would indicate the essential role of antibodies in immunity to acute Chagas' disease through T-dependent immune response.

Sodium dodecyl sulfate-polyacrylamide gel electrophoresis patterns of proteins and externally exposed labeled surface constituents were analyzed in promastigotes of three etiological agents of kala azar (Leishmania donovani, HS70 strain from India; L. chagasi, Imperatriz strain from Brazil; L. infantum, ITMPA K263 strain from Morocco and MO strain from France). Coomassie blue-stained gels showed similar protein patterns for L. donovani and L. chagasi and a more distinct one for L. infantum. Surface radioiodination with two different methods, lactoperoxidase and IODO-GEN, gave identical autoradiographic patterns for each parasite. Four major labeled proteins with apparent Mr values of 65,000, 60,000, 50,000, and 26,000 were detected in both L. chagasi and L. donovani. However, the radioiodinated polypeptide pattern of L. infantum only showed two major bands with an apparent Mr of 62,000 and a doublet of 26,000 to 23,000. Immunoprecipitation of detergent extracts of labeled promastigote subspecies with immune sera from rabbits immunized with either L. chagasi or L. infantum and from patients and mice infected with these two parasites, as well as with a monoclonal antibody against the surface of L. donovani promastigotes, demonstrated that the surface antigenic expression of L. infantum is different from that noticed in the two other subspecies, which are similar. Immunofluorescence experiments with some of these antibodies confirmed these results. The present findings should be considered in taxonomic and immunological studies in visceral leishmaniasis.

The effect of neonatally initiated injections of anti-mu rabbit antiserum on immunity of rats against Trypanosoma cruzi infection was investigated in vivo. Anti-mu treatment resulted in a loss of immunoglobulin M (IgM) and IgG2a synthesis and, subsequently, of antibody production. These rats so treated were shown to be significantly more susceptible to the acute phase of the infection than the control rats treated with normal rabbit serum, as measured by increased parasitemia and mortality. These results indicate the essential role of antibodies, probably in association with complement or effector cells or both, in immunity to acute Chagas' disease.

Nine monoclonal antibodies against surface antigens of sporozoites of the simian malaria parasite Plasmodium knowlesi were produced by fusion of plasmacytoma cells with spleen cells of a mouse immunized with the parasites. Immunoprecipitation of extracts of [35S]methionine-labeled sporozoites with seven of the monoclonals identified the same three polypeptides with apparent molecular weights of 52,000 (Pk52), 50,000 (Pk50) and 42,000 (Pk42). These antigens also were recognized by serum of a rhesus monkey immunized with and protected against P. knowlesi sporozoites. Pulse--chase experiments indicated that the higher molecular weight proteins are precursors of Pk42. As shown by trypsin treatment of viable sporozoites, Pk42 is a surface antigen whereas Pk52 and Pk50 appear to be intracellular. Three of the monoclonal antibodies also reacted with a membrane antigen of sporozoites of another simian malaria, P. cynomolgi, and one monoclonal antibody reacted with sporozoites of human malaria, P. falciparum. When assayed for sporozoite neutralizing activity, most of the antibodies and their Fab fragments, which recognize Pk52, Pk50, and Pk42, abolished parasite infectivity.

Toxoplasma gondii alone does not induce tumor necrosis factor alpha (TNF-alpha) secretion by human monocytes and macrophages. Nevertheless, sera from infected patients with high titers of specific immunoglobulin G antibodies against T. gondii induce TNF-alpha secretion, which is significantly higher than the corresponding induction by negative sera (P less than 0.05). After incubation with the positive serum, parasites also induce secretion of this cytokine, but TNF-alpha levels are lower (11.4 to 71.8%) than those obtained with positive serum alone. Therefore, this secretion seems to be elicited in part by antibody-T. gondii complexes and/or another unidentified factor(s), probably different from lipopolysaccharide, interleukin-1, TNF-alpha, and gamma interferon. In this study, monocytes secreted more TNF-alpha into the culture fluid than macrophages did (P less than 0.05), and no correlation was observed between secretion of this cytokine by the monocytes and the intracellular multiplication of the parasites, evaluated by [3H]uracil incorporation. Sera from patients with other infections diseases did not induce secretion of TNF-alpha; however, serum free of antibodies to T. gondii, obtained from patients with leishmaniosis, also stimulated secretion of the cytokine.

We investigated the luminal surface of the continuous endothelium of the microvasculature of the murine heart and diaphragm to find out whether it has differentiated microdomains. The probes were ferritin molecules, cationized to pI's 6.8, 7.15, 7.6, 8.0 and 8.4, which were introduced by retrograde or anterograde perfusion through the aorta or vena cava after the blood was removed from the vasculature. The pattern of labeling was analyzed by electron microscopy and assessed quantitatively by morphometry in arterioles, capillaries, and venules identified in bipolar microvascular fields in the diaphragm. The results showed that the plasmalemma proper was heavily but discontinuously labeled by all cationized ferritins (CF) used, the labeling being less extensive on the venular endothelium. CF had access as individual molecules to a fraction of the vesicular population opened on the luminal front of the endothelium. Plasmalemmal vesicle labeling increased from approximately 10 to approximately 25% as the pI decreased from 8.4 to 6.8. Vesicle labeling also increased with CF concentration in the perfusate. All CF binding sites were removed by pronase and papain. Heparinase and heparitinase caused only a slight reduction in CF labeling. Neuraminidase decreased the extent and density of labeling, especially on the plasmalemma proper of the venular endothelium; this decrease was particularly pronounced in old animals.

The major surface antigen from the proliferative form ofToxoplasma gondii(P-30 or SAG-1) was chosen as a target for exploration ofToxoplasma gondiireactivation in sera from immunocompromised patients. Samples were obtained from 37 HIV-infected subjects with lymphocyte levels of CD4+ <200/mm3. The prevalence of IgG antibodies toToxoplasma gondiiwas 64.9 %. Ten patients had clinical symptoms of reactivated toxoplasmosis; eight of these hadToxoplasmaencephalitis. The SAG-1 epitopes were found as circulating antigen in five cases with an immunocapture enzyme immunoassay (EIA). The EIA was improved with an IgG1 monoclonal antibody to SAG-1 and a streptavidinbiotin amplification. The sensitivity, specificity and positive predictive value were 30, 92 and 60 %, respectively. The SAG-1 levels were compared with different biological parameters such as HIV p24 antigen, β2microglobulin, CD4+ cell count and IgG antibodies toToxoplasma gondii.The levels of SAG-1 in these patients were significantly higher than those in the 75 healthy control persons with or without a chronicToxoplasma gondiiinfection. Therefore, SAG-1 may be involved as a marker of reactivated toxoplasmosis in HIV-infected patients.

Abstract: We propose modified warm blood antegrade-retrograde reperfusion (WBARR) of arrested hearts as a metabolic model with which to study substrate exchange and energy metabolism during the recovery phase after 90 min of ischaemia in man. Eleven anaesthetized patients undergoing aorto-coronary bypass were studied during WBARR. The protocol was designed as follows: period 1, a warm blood reperfusion with potassium (3 min); period 2, a warm blood reperfusion without potassium (2 min). The perfusion flow rate averaged 250�2 ml/min at the beginning of period 1 and 218�19 ml/min at the beginning and at the end of period 2; the perfusion was performed antegradely and retrogradely in the arrested hearts. Samples were simultaneously taken from the coronary venous sinus (CVS) and from the aortic root needle (AR). At the beginning of WBARR lactate release was 85�44 μmol/min and at the end it had significantly decreased to 21�99 μmol/min (P<0.03). Simultaneously, non-esterified fatty acids (NEFA) and β-hydroxy-butyrate were initially released (71�61 and 22�66 μmol/min, respectively), while at the end of the WBARR there was an uptake of both NEFA (20�22 μmol/min; P<0.01) and β-hydroxy-butyrate (12�35 μmol/min; P=0.290). Alanine, glycerol and branched chain amino acid balance across the heart did not significantly change. In summary after 90 min of ischaemia the heart energy metabolism is mainly anaerobic and based on glucose consumption, with lactate, NEFA and amino acids, which are mainly released. After 5 min of WBARR (recovery from ischaemia), lactate release is significantly reduced and NEFA becomes the energy supply of the heart. In conclusion, (1) WBARR is a valuable method with which to study myocardial metabolism in anaesthetized humans and may be combined with the use of tracers; (2) the study of myocardial metabolism in arrested hearts eliminates the imprecisions arising from the non-continuous coronary blood flow; (3) NEFA become an important source of energy utilized by human hearts in the recovery phase from ischaemia.

Virulent strains of the coccidian parasiteToxoplasma gondii become attenuated so as to survive and complete their life cycle; however, it is not known whether the attenuation process is attributable to an innate cystogenic capacity of the parasite or to host-induced mechanisms. This report presents direct evidence of RH cystogenesis in non-immunised Fischer rats and subsequent attenuation of RH pathogenicity in non-immunised mice following a single passage through rats. Taken together, these preliminary observations tend to suggest that at least one mechanism ofT. gondii involves intermediate host attenuation.

In 2 independent samples of low-birth-weight infants the proportion of females and homozygotes for a series of polymorphic systems was higher in light-for-dates than in preterm babies. The observation seems to give support to the hypothesis that homozygosity for ‘normal’ polymorphisms may decrease in general intrauterine growth rate. Since it is known that survival rate is strongly related to birth weight, a correlation between growth retardation and homozygosity may have a major role in the maintenance of such polimorphisms.

Both neural and humoral systems participate in the control of blood flow to various organs. Exercise places the greatest demands on the circulation. At rest, in humans, skeletal muscle receives somewhere between 15% and 20% of cardiac output, while during maximal exercise, this percentage reaches a value of 80% to 90%. The active human muscles have a high-flow capacity that exceeds the capacity of the heart to pump blood. Measurements in single human muscle have indicated that blood flow may be inhomogeneous, that is, probably depending on variations of the vasomotor tone of the muscle mediated by humoral and neural factors. Exercise raises cardiac output and coronary blood flow, which rise linearly with increases in heart rate. In normal young men, coronary blood flow averages 280 ml/min/100 g of the left ventricle and reaches as high as 390 ml/min during moderately severe exercise, requiring about 85% of maximal heart rate. In nonexercising organs, the blood flow decreases at about 20% to 40% of the resting values, being the net result of competing vasoconstrictor and vasodilator drives.

Some 40% of birth weight variation can be attributed to genetic factors, half of them being fetal and the other half maternal. "Normal variation" would give a 10% contribution to the small-for-dates population. The distribution of phosphoglucomutase 1 (PGM1), adenosine deaminase (ADA), erythrocyte acid phosphatase (ACP1) and adenilatekinase (AK) polymorphisms was studied in 91 low birth weight infants (LBWI). ACP1and ADA gene frequency distribution in LBWI showed a significant increase (p<0.01 and p<0.05) of the proportions of the more common alleles (Pband ADA1) and a reduction of heterozygotes as compared to adults or unselected newborn. The presence of multiple molecular forms of enzymes may protect the delicate balance of the developing zygote against the deleterious effects of environmental variations. Therefore the present data suggest that the (low) degree of heterozygosity for enzyme polymorphisms may represent a significant part of "normal variation" contribution to the low birth weight population.