Are "EIT Waves" Fast-Mode MHD Waves?

We examine the nature of large-scale, coronal, propagating wave fronts (``EIT waves'') and find they are incongruous with solutions using fast-mode MHD plane-wave theory. Specifically, we consider the following properties: non-dispersive single pulse manifestions, observed velocities below the local Alfven speed, and different pulses which travel at any number of constant velocities, rather than at the ``predicted'' fast-mode speed. We discuss the possibility of a soliton-like explanation for these phenomena, and show how it is consistent with the above-mentioned aspects.Comment: to be published in the Astrophysical Journa

Recurrence and progression of periodontitis and methods of management in long-term care: A systematic review and meta-analysis

Aim: To systematically review the literature to evaluate the recurrence of disease of people in long-term supportive periodontal care (SPC), previously treated for periodontitis, and determine the effect of different methods of managing recurrence. The review focused on stage IV periodontitis. Materials and methods: An electronic search was conducted (until May 2020) for prospective clinical trials. Tooth loss was the primary outcome. Results: Twenty-four publications were retrieved to address recurrence of disease in long-term SPC. Eight studies were included in the meta-analyses for tooth loss, and three studies for disease progression/recurrence (clinical attachment level [CAL] loss ≥2 mm). For patients in SPC of 5–20 years, prevalence of losing more than one tooth was 9.6% (95% confidence interval [CI] 5%–14%), while experiencing more than one site of CAL loss ≥2 mm was 24.8% (95% CI 11%–38%). Six studies informed on the effect of different methods of managing recurrence, with no clear evidence of superiority between methods. No data was found specifically for stage IV periodontitis. Conclusions: A small proportion of patients with stage III/IV periodontitis will experience tooth loss in long-term SPC (tendency for greater prevalence with time). Regular SPC appears to be important for reduction of tooth loss. No superior method to manage disease recurrence was found

Automated Analysis of MUTEX Algorithms with FASE

In this paper we study the liveness of several MUTEX solutions by representing them as processes in PAFAS s, a CCS-like process algebra with a specific operator for modelling non-blocking reading behaviours. Verification is carried out using the tool FASE, exploiting a correspondence between violations of the liveness property and a special kind of cycles (called catastrophic cycles) in some transition system. We also compare our approach with others in the literature. The aim of this paper is twofold: on the one hand, we want to demonstrate the applicability of FASE to some concrete, meaningful examples; on the other hand, we want to study the impact of introducing non-blocking behaviours in modelling concurrent systems.Comment: In Proceedings GandALF 2011, arXiv:1106.081

Immediate implant placement in fresh alveolar sockets with a minimal split-thickness envelope flap. A randomised controlled clinical trial.

OBJECTIVES: Comparing PES/WES scores, modified success rate, survival, success, buccal bone thickness and patient-reported outcomes of immediate dental implants placed in fresh alveolar sockets using a flap or a minimal split-thickness envelope flap (MSTEF). MATERIALS AND METHODS: Implants following random assignment into a flap or MSTEF group were placed immediately in anterior and premolar areas. Guided bone regeneration and autogenous connective tissue graft were used in all cases. A temporary prosthesis was provided followed by the final prosthesis at 16-18 weeks. Success and survival rates together with radiographic buccal bone thickness and patient satisfaction were evaluated at 12 months post-loading. The aesthetic outcome was evaluated through the Pink (PES) and White (WES) Aesthetic Score by 8 blind clinicians of different training background and incorporated in modified success criteria. RESULTS: 28 implants were placed on 28 patients. No statistically significant differences were noted in PES (10.54 control vs. 10.80 test), WES scores (6.97 control vs. 6.95 test) or success criteria including aesthetic parameters (modified success criteria) for the different specialty groups (Range 69%-92%). In addition, no statistically significant differences were noted in survival (100%), success (100%), buccal wall thickness between control (0.72 +/-0.22) and test group (0.92+/-0.31) and patients' reported outcomes. CONCLUSIONS: Immediate dental implant treatment with flap/ MSTEF provided similar mean PES/WES scores, modified success rate, survival, mean buccal bone levels and patients' satisfaction. However, aesthetic failures were common in both groups

Immediate implant placement in fresh alveolar sockets with a minimal split-thickness envelope flap: A randomised controlled clinical trial

OBJECTIVES: Comparing PES/WES scores, modified success rate, survival, success, buccal bone thickness and patient-reported outcomes of immediate dental implants placed in fresh alveolar sockets using a flap or a minimal split-thickness envelope flap (MSTEF). MATERIALS AND METHODS: Implants following random assignment into a flap or MSTEF group were placed immediately in anterior and premolar areas. Guided bone regeneration and autogenous connective tissue graft were used in all cases. A temporary prosthesis was provided followed by the final prosthesis at 16-18 weeks. Success and survival rates together with radiographic buccal bone thickness and patient satisfaction were evaluated at 12 months post-loading. The aesthetic outcome was evaluated through the Pink (PES) and White (WES) Aesthetic Score by 8 blind clinicians of different training background and incorporated in modified success criteria. RESULTS: 28 implants were placed on 28 patients. No statistically significant differences were noted in PES (10.54 control vs. 10.80 test), WES scores (6.97 control vs. 6.95 test) or success criteria including aesthetic parameters (modified success criteria) for the different specialty groups (Range 69%-92%). In addition, no statistically significant differences were noted in survival (100%), success (100%), buccal wall thickness between control (0.72 +/-0.22) and test group (0.92+/-0.31) and patients' reported outcomes. CONCLUSIONS: Immediate dental implant treatment with flap/ MSTEF provided similar mean PES/WES scores, modified success rate, survival, mean buccal bone levels and patients' satisfaction. However, aesthetic failures were common in both groups

Validation of a new prognostic model to easily predict outcome in renal cell carcinoma: The GRANT score applied to the ASSURE trial population

Background: Prognostic scores have been developed to estimate the risk of recurrence and the probability of survival after nephrectomy for renal cell carcinoma (RCC). The use of these tools, despite being helpful to plan a customized schedule of follow-up, to the patient's tailored counselling and to select individuals who could potentially benefit from adjuvant treatment, currently is not routine, due to their relative complexity and to the lack of histological data (i.e. necrosis).Patients and methods: We developed a simple score called GRade, Age, Nodes and Tumor (GRANT) based on four easily obtained parameters: Fuhrman grade, age, pathological nodal status and pathological tumor size. Patients with 0 or 1 factor are classified as favorable risk, whereas patients with two or more risk factors as unfavorable risk. The large population of RCC patients from the ASSURE adjuvant trial was used as independent dataset for this external validation, to investigate the prognostic value of the new score in terms of disease-free survival and overall survival and to evaluate its possible application as predictive tool. Statistical analyses were carried out by the Department of Biostatistics & Computational Biology, Dana-Farber Cancer Institute (Boston, USA) for the ASSURE trial patients' population.Results: The performance of the new model is similar to that of the already validated score systems, but its strength, compared with the others already available, is the ease and clarity of its calculation, with great speed of use during the clinical practice. Limitations are the use of the Fuhrman nuclear grade, not valid for rare histologies, and the TNM classification modifications over time.Conclusion: The GRANT score demonstrated its potential usefulness for clinical practice

Return current instability and its effects on beam-plasma system

The return current induced in a plasma by a relativisitc electron beam generates a new electron-ion two-stream instability (return current instability). Although the effect of these currents on the beam-plasma e-e instability is negligible, there exists a range of wave numbers which is unstable only to return current (RC) instability and not to e-e instability. The electromagnetic waves propagating along the direction of the external magnetic field, in which the plasma is immersed, are stabilized by these currents but the e.m. waves with frequencies,ω2≪Ω e 2 ≪ω pe 2 (Ω e and ω pe being cyclotron and plasma frequency for the electrons of the plasma respectively) propagating transverse to the magnetic field get destabilized. Heuristic estimates of plasma heating, due to RC instability and due to decay of ion-acoustic turbulence generated by the return current, are made. The fastest time scale on which the return current delivers energy to the plasma due to the scattering of ion-sound waves by the electrons can be ∼ω pi -1 (ω pi being the plasma frequency for the ions)

To Splint or Not to Splint Short Dental Implants Under the Same Partial Fixed Prosthesis? One-year Post-loading Data From a Multicentre Randomised Controlled Trial

PURPOSE. To compare the clinical outcomes of two adjacent 6-mm-long dental implants splinted under the same prosthesis (control group) versus two identical implants sup-porting single crowns (test group). MATERIALS AND METHODS. Forty-seven patients with edentulous posterior (premolars and/or molars) jaws received two adjacent 6-mm-long dental implants, which were sub-merged. Four months later, at impression taking, patients were randomised to receive splinted or unsplinted definitive cemented metal-composite prostheses. Unfortunately, four patients died before randomisation and three patients lost five implants, so only 40 patients were randomised, according to a parallel-group design, to have both implants splinted under the same partial fixed prosthesis (19 patients) or with two single crowns (21 patients). Outcome measures were: prosthesis and implant failures, any complica-tions, peri-implant marginal bone level changes and patient satisfaction. Patients were followed-up to 1 year after loading. RESULTS. One patient from the splinted group dropped out. No implant failures occurred after randomisation. One complication occurred in the unsplinted group versus no complications at splinted implants, the difference not being statistically different (Fisher’s exact test P = 1.000; difference in proportions =-0.04; 95% CI-0.16 to 0.09). Both groups presented significant peri-implant marginal bone loss at 1 year after loading (P<0.05), respectively-0.36 (0.45) mm at splinted implants and-0.17 (0.31) mm at unsplinted implan-ts, but there were no statistically significant differences between the two groups (mean difference 0.19 mm; 95% CI-0.10 to 0.48; P = 0.194). All patients were fully or reasonably satisfied with the treatment, with the exception of two patients, both from the splinted group: one patient was not sure about the aesthetics, and another would not undergo the same treatment again. CONCLUSIONS. The present data seems to suggest that up to 1 year after loading the prognosis of short implants, mostly placed in mandibles characterised by dense bone quality, may not be influenced by splinting or not under the same fixed prostheses. Howe-ver, these preliminary results need to be confirmed by larger trials with follow-ups of at least 5 years