Investigation of plasma accelerator /cyclotron resonance propulsion system/ Final report

Electron cyclotron resonance plasma accelerators for space propulsion system

Microwave Driven Magnetic Plasma Accelerator Studies (CYCLOPS)

A microwave-driven cyclotron resonance plasma acceleration device was investigated using argon, krypton, xenon, and mercury as propellants. Limited ranges of propellant flow rate, input power, and magnetic field strength were used. Over-all efficiencies (including the 65% efficiency of the input polarizer) less than 10% were obtained for specific impulse values between 500 and 1500 sec. Power transfer efficiencies, however, approached 100% of the input power available in the right-hand component of the incident circularly polarized radiation. Beam diagnostics using Langmuir probes, cold gas mapping, r-f mapping and ion energy analyses were performed in conjunction with an engine operating in a pulsed mode. Measurements of transverse electron energies at the position of cyclotron resonant absorption yielded energy values more than an order of magnitude lower than anticipated. The measured electron energies were, however, consistent with the low values of average ion energy measured by retarding potential techniques. The low values of average ion energy were also consistent with the measured thrust values. It is hypothesized that ionization and radiation limit the electron kinetic energy to low-values thus limiting the energy which is finally transferred to the ion. Thermalization by electron-electron collision was also identified as an additional loss mechanism. The use of light alkali metals, which have relatively few low lying energy levels to excite, with the input power to mass ratio selected so as to limit the electron energies to less than the second ionization potential, is suggested. It is concluded, however, that the over-all efficiency for such propellants would be less than 40 per cent

Indacaterol/glycopyrronium/mometasone fixed dose combination for uncontrolled asthma

Introduction: Asthma symptoms can be relieved through a maintenance treatment combining long-acting β2-agonist and inhaled corticosteroids (LABA/ICS). However, for patients with inadequately controlled asthma, the LABA/ICS combination might not be sufficient, and clinical guidelines recommend the administration of inhaled long-acting muscarinic antagonists (LAMA) as an add-on therapy to better control asthma and improve lung function. For nearly two decades, the only LAMA to be approved on the market has been tiotropium. Areas covered: We reviewed recent clinical studies evaluating the safety and efficacy of LABA/LAMA/ICS fixed dose combinations by searching the PubMed database. Molecular mechanisms and clinical data support the use of a once-daily, single-inhaler fixed dose combination of the LABA/LAMA/ICS indacaterol/glycopyrronium/mometasone (IND/GLY/MF), the first therapy combining three agents in a fixed dose approved in Europe for the treatment of uncontrolled asthma. Expert opinion: IND/GLY/MF was superior to both IND/MF and salmeterol/fluticasone, a well-established LABA/ICS combination improving the lung function in uncontrolled asthma. Moreover, IND/GLY/MF, delivered through the Breezhaler inhaler in a single inhalation, is the first inhaled therapy prescribed alongside a digital companion, a sensor and the Propeller app, allowing for improved treatment adherence, reduced rescue inhaler usage and hospitalizations, increased patient satisfaction and asthma control

Attenuation of induced bronchoconstriction in healthy subjects: effects of breathing depth.

The effects of breathing depth in attenuating induced bronchoconstriction were studied in 12 healthy subjects. On four separate, randomized occasions, the depth of a series of five breaths taken soon (approximately 1 min) after methacholine (MCh) inhalation was varied from spontaneous tidal volume to lung volumes terminating at approximately 80, approximately 90, and 100% of total lung capacity (TLC). Partial forced expiratory flow at 40% of control forced vital capacity (V(part)) and residual volume (RV) were measured at control and again at 2, 7, and 11 min after MCh. The decrease in V(part) and the increase in RV were significantly less when the depth of the five-breath series was progressively increased (P < 0.001), with a linear relationship. The attenuating effects of deep breaths of any amplitude were significantly greater on RV than V(part) (P < 0.01) and lasted as long as 11 min, despite a slight decrease with time when the end-inspiratory lung volume was 100% of TLC. In conclusion, in healthy subjects exposed to MCh, a series of breaths of different depth up to TLC caused a progressive and sustained attenuation of bronchoconstriction. The effects of the depth of the five-breath series were more evident on the RV than on V(part), likely due to the different mechanisms that regulate airway closure and expiratory flow limitation

Airway responsiveness to methacholine: effects of deep inhalations and airway inflammation.

Abstract We determined the dose-response curves to inhaled methacholine (MCh) in 16 asthmatic and 8 healthy subjects with prohibition of deep inhalations (DIs) and with 5 DIs taken after each MCh dose. Flow was measured on partial expiratory flow-volume curves at an absolute lung volume (plethysmographically determined) equal to 25% of control forced vital capacity (FVC). Airway inflammation was assessed in asthmatic subjects by analysis of induced sputum. Even when DIs were prohibited, the dose of MCh causing a 50% decrease in forced partial flow at 25% of control FVC (PD(50)MCh) was lower in asthmatic than in healthy subjects (P < 0.0001). In healthy but not in asthmatic subjects, repeated DIs significantly decreased the maximum response to MCh [from 90 +/- 4 to 62 +/- 8 (SD) % of control, P < 0.001], increased PD(50)MCh (P < 0.005), without affecting the dose causing 50% of maximal response. In asthmatic subjects, neither PD(50)MCh when DIs were prohibited nor changes in PD(50)MCh induced by DIs were significantly correlated with inflammatory cell numbers or percentages in sputum. We conclude that 1) even when DIs are prohibited, the responsiveness to MCh is greater in asthmatic than in healthy subjects; 2) repeated DIs reduce airway responsiveness in healthy but not in asthmatic subjects; and 3) neither airway hyperresponsiveness nor the inability of DIs to relax constricted airways in asthmatic subjects is related to the presence of inflammatory cells in the airways

Step-down from high dose fixed combination therapy in asthma patients: a randomized controlled trial.

Asthma guidelines suggest that therapy can be reduced once asthma is controlled. Despite these recommendations, asthmatic patients are seldom stepped down in clinical practice, and questions remain about when and how to reduce asthma therapy. The purpose of the present study was to evaluate lung function and asthma control in patients who were stepped down from the highest recommended dose of inhaled corticosteroid/long acting \u3b22 agonist combination therapy. METHODS: This was a prospective, randomised, controlled, two-arm parallel group study. Asthmatic patients who were fully controlled with a high daily dose (1000/100\u2009\u3bcg) of fluticasone/salmeterol were randomly assigned to 6\u2009months of open-label treatment with either 500/100\u2009\u3bcg fluticasone/salmeterol Diskus daily or 400/24\u2009\u3bcg extrafine beclomethasone/formoterol pMDI daily. The primary outcome was the change in morning peak expiratory flow (PEF) values between baseline and the end of treatment. The secondary outcomes included asthma control and exacerbation frequency. RESULTS: Four hundred twenty-two patients were included in the analysis. The PEF values remained above 95% of the predicted values throughout the study. The end-study morning PEF rates showed equivalence between the groups (difference between means, 2.49\u2009L/min; 95% CI, -13.43 to 18.42). No changes from baseline were detected in PEF and forced expiratory volume in 1 second measured at the clinics, in the symptom scores or in the use of rescue medication. Asthma control was maintained in 95.2% of the patients at 6\u2009months. No significant differences between the groups were detected in any other parameter, including exacerbation frequency and adverse events. CONCLUSIONS: Stepping down patients whose asthma is controlled with the highest recommended dose of fluticasone/salmeterol to either 500/100\u2009\u3bcg fluticasone/salmeterol daily or 400/24\u2009\u3bcg extra-fine beclomethasone/formoterol daily provides comparable maintenance of lung function and asthma control. TRIAL REGISTRATION: clinicaltrials.gov NCT00497237

Tongue Reconstruction with Buccinator Myomucosal Island Flaps: Technical Considerations, Oncologic Safety, Functional Outcomes and QoL Assessment—A Retrospective Observational Study

The objective of this study was to investigate the effectiveness of buccinator myomucosal island flaps for tongue reconstruction following malignant tumor resections. A retrospective study was performed on 52 patients who underwent tongue reconstructions with buccinator myomucosal island flaps between 2012 and 2020. We reviewed the flap type and size, harvesting time, recipient- and donor-site complications, postoperative oncologic outcomes, functional recovery and QoL assessment. All of the flaps were transposed successfully without any total flap loss. Neither in the primary site nor in the neck were cancer relapses observed. An evaluation of the sensitivity revealed that 96.1% of patients experienced a recovery of touch, two-point and pain sensations. There were significant differences between the flap and the native mucosa in terms of the tactile (p &lt; 0.001), pain (p &lt; 0.001) and two-point (p &lt; 0.001) thresholds. The average swallowing score recorded was 6.1 out of 7, with only minor complaints. The quality of life assessments demonstrated high scores across physical (24.5 out of 28), social (25.8 out of 28), emotional (20.3 out of 24) and functional (25 out of 28) aspects. The present study showed how buccinator myomucosal island flaps represent an effective and functional tongue reconstructive option, requiring a short operative time with a low rate of donor site morbidity, and with evidence of long-term oncologic safety and high quality of life

PLANT EXTRACTS AS GREEN POTENTIAL STRATEGIES TO CONTROL THE BIODETERIORATION OF CULTURAL HERITAGE

The biodeterioration of historic-artistic manufacts is related to several biological systems, including fungi and bacteria, whose metabolic activities and vegetative development have a direct consequence on the conservation of cultural assets. Generally, different chemical compounds are utilized as biocides in order to control biodeteriogens growth, but recently the attention has been focused on potential risks of their use towards human health (operators, visitors) and the environment. In order to develop alternative methods, various natural products have been tested, particularly to control the colonization by fungi and bacteria. In this study, antimicrobial activity of three different plant products, Tea tree essential oil, Calamintha nepeta and Allium sativum L. extracts, has been evaluated against Bacillus subtilis, Micrococcus luteus, Penicillium chrysogenum and Aspergillus spp. (previously isolated from colonized artworks) through three different in vitro antimicrobial assays (micro-dilution in microtiter plates, well plates diffusion and agar disc diffusion method). The bioassays show a different microbial susceptibility to plant extracts, establishing for each bacteria and fungi the Minimum Inhibitory Concentration (MIC) and defining the diameter of the growth inhibition area. This result supports the data reported in literature and shows an important potential suggestion for the possible use in the control of biodeterioration of cultural heritage, safe both for human health and environment

Microbiological surveillance of hospital ventilation systems in departments at high risk of nosocomial infections

The air in hospital wards with patients at high risk (Surgeries, Intensive Care Units and Bone Marrow Transplant Centers) has been surveyed less than the one in Operating Rooms. Therefore in this study we considered useful to verify the microbic contamination of the air of those wards evaluating the consistency of ventilation systems in relation also to the presence and location of HEPA absolute filters. Seven departments of Genoese San Martino Hospital at high risk of infection were taken into account. In there, environmental investigations have been performed by air samplings and by analyzing bacterial and fungal growth on plates after an incubation period. Almost 60% of all samples taken in wards yielded a positive result and the average values of bacterial and aspergillar charges measured at air flow emission openings decisively exceed the ones considered standard in operating rooms. Still, the average values of airborne bacterial charges were significantly higher in those wards equipped with central filters (p inf. 0.001), while as far as the aspergillar charge is concerned, no statistically relevant differences were noticed. In wards with ventilation system, the bacterial charge value raises from the emission grids to the middle of the room and to the aspiration grids, while the ward not equipped with a ventilation system presents in the middle of the room an average bacterial charge 2 to 10 times higher than the one in other wards. The average values regarding bacterial and aspergillar charges resulted quite high in all the departments surveyed. Nevertheless, if we take into account ventilation systems equipped with absolute filters HEPA located centrally or peripherally, it can be outlined that the air quality from the point of view of both microbic and aspergillar contamination turns out to be decisively better in systems with peripheral filters. Moreover, a compared analysis of the three Hematology wards allows us to infer that the presence of artificial ventilation systems can lower the bacterial and fungal compared with a ward with natural ventilation

Effectiveness of benralizumab in severe eosinophilic asthma: Distinct sub-phenotypes of response identified by cluster analysis.

Background: Benralizumab is effective in severe eosinophilic asthma (SEA), but suboptimal responses are observed in some patients. Although several factors have been associated with benralizumab response, no cluster analysis has yet been undertaken to identify different responsiveness sub-phenotypes. Objective: To identify SEA sub-phenotypes with differential responsiveness to benralizumab. Methods: One hundred and five patients diagnosed with SEA who had completed 6&nbsp;months of benralizumab treatment were included in a hierarchical cluster analysis based on a set of clinical variables that can be easily collected in routine practice (age, age at disease onset, disease length, allergen sensitization status, blood eosinophil count, IgE levels, FEV1% predicted, nasal polyposis, bronchiectasis). Results: Four clusters were identified: Clusters 2 and 3 included patients with high levels of both IgE and eosinophils (type-2 biomarkers high), whereas Clusters 1 and 4 included patients with only one type-2 biomarker at a high level: IgE in Cluster 1 and eosinophils in Cluster 4. Clusters 2 and 3 (both type-2 biomarkers high) showed the highest response rate to benralizumab in terms of elimination of exacerbations (79% and 80% respectively) compared to Clusters 1 and 4 (52% and 60% respectively). When super-response (the absence of exacerbation without oral corticosteroid use) was assessed, Cluster 2, including patients with more preserved lung function than the other clusters, but comparable exacerbation rate, oral corticosteroid use and symptom severity, was the most responsive cluster (87.5% of patients). Conclusions: Our cluster analysis identified benralizumab differential response sub-phenotypes in SEA, with the potential of improving disease treatment and precision management